# Total parietal peritonectomy for 61 patients: a retrospective study

R. Saadeh, A. Berthet, S. Marchant, Francois Kraus, Othman Aissaoui, Fabrice Narducci, Eric Leblanc, Delphine Hudry

► To cite this version:

R. Saadeh, A. Berthet, S. Marchant, Francois Kraus, Othman Aissaoui, et al. Total parietal peritonectomy for 61 patients: a retrospective study. European Journal of Gynaecological Oncology, 2022, European Journal of Gynaecological Oncology, 43, 10.31083/j.ejgo4301009. hal-04415258

HAL Id: hal-04415258

https://hal.univ-lille.fr/hal-04415258

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Distributed under a Creative Commons Attribution 4.0 International License
# Total parietal peritonectomy for 61 patients: a retrospective study

R. Saadeh, A. Berthet, S. Marchant, Francois Kraus, Othman Aissaoui, Fabrice Narducci, Eric Leblanc, Delphine Hudry

► To cite this version:

R. Saadeh, A. Berthet, S. Marchant, Francois Kraus, Othman Aissaoui, et al. Total parietal peritonectomy for 61 patients: a retrospective study. European Journal of Gynaecological Oncology, 2022, European Journal of Gynaecological Oncology, 43, 10.31083/j.ejgo4301009. hal-04415258

HAL Id: hal-04415258

https://lilloa.hal.science/hal-04415258v1

Submitted on 24 Jan 2024

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons Attribution 4.0 International License
*Original Research*

# Total parietal peritonectomy for 61 patients: a retrospective study

Ralph Saadeh<fnref n="1" />,*, Angélique Berthet<fnref n="1" />, Séverine Marchant<fnref n="1" />, François Kraus<fnref n="1" />, Othman Aissaoui<fnref n="1" />, Fabrice Narducci<fnref n="1" />,<fnref n="2" />, Eric Leblanc<fnref n="1" />,<fnref n="2" />, Délphine Hudry<fnref n="1" />,<fnref n="2" />

## Abstract

**Objective:** To evaluate the morbidity of total parietal peritonectomy (TPP) during cytoreduction surgery, and its impact on the site of recurrence of different peritoneal surface malignancies (PSM). **Methods:** We led a retrospective study in a French tertiary cancer institution (Centre Oscar Lambret - Lille) experienced in treating PSM over a 6-year period from 2012 to 2018. All patients underwent a total parietal peritonectomy during a debulking surgery for PSM including ovarian cancer, appendiceal pseudomyxoma peritonei or peritoneal mesothelioma. **Results:** Among the 61 patients included in this study, 49 patients (80.3%) had an ovarian cancer. The rate of complete tumor resection reached 86.9% with almost 69% of surgeries being highly complex. 73.8% were transfused during the surgical procedure. The median length of hospital stay was 10 days including 7 days in Intensive Care Unit. Overall, 19 patients (31.1%) had an early postoperative complication, including 3 with a grade IIIB complication of Clavien Dindo classification. With a median follow-up of 30 months, the estimated disease-free survival in the ovarian cancer subgroup who had an initial peritonectomy (n = 42) was 84.7% at 1 year and 12.0% at 3 year. The main site of first and second recurrence was peritoneal (42% and 14%). **Conclusion:** TPP is a safe surgical procedure to treat peritoneal surface malignancies and their recurrences with a low rate of grade IIIB morbidity and no treatment-related death and allow optimal surgery. In this study there is no atypical recurrence site, such as abdominal muscle involvement.

**Keywords:** Ovarian cancer; Peritonectomy; Primary surgery debulking; Interval debulking surgery; Neo-adjuvant chemotherapy

## 1. Introduction

Peritonectomy has been used for the treatment of peritoneal surface malignancies (PSM) including colorectal cancer [1,2], appendiceal pseudomyxoma peritonei [3], and peritoneal mesothelioma [4]. Baratti et al. [5] was the first to evaluate the concept of total parietal peritonectomy (TPP) in peritoneal mesothelioma. Pelvic peritonectomy has been applied in advanced ovarian cancer with peritoneal carcinomatosis and has increased the rate of complete cytoreduction up to 60% [6].

As a technique, peritonectomy has been described and standardized first by Sugarbaker in 1995 [7] for colon cancer then modified by other groups depending on histopathology [8]. According to Sugarbaker [9], only abnormal peritoneum should be excised. But the extensive resection of tumors showed contradictory outcomes. Kyriazanos et al. [10], described the “cocoon technique” a standardized approach to achieve total extraperitoneal peritonectomy. Usually coupled with Hyperthermic Intraperitoneal Chemoperfusion (HIPEC), extensive cytoreduction surgery (CRS) has been criticized for its morbidity and mortality rates along with its benefits for all patients [11]. On the other hand, other studies have shown significant improvements in rates of survival and acceptable rates of morbidity [12,13].

In order to obtain an optimal cytoreduction, surgeons perform a TTP to resect all visible disease, since any residual disease represents a potential risk for recurrence, especially in chemo-resistant tumors.

However, removing only visible residual disease following neoadjuvant chemotherapy (NACT) and not “normally appearing peritoneum” that was previously affected before chemotherapy, showed a high rate of recurrence of 70% with the commonest site being the peritoneum, at previous disease sites [14]. Therefore, it may be hypothesized that complete removal of the peritoneum affected prior to NACT may prevent or delay the recurrence in these patients.

Another hypothesis of the TPP benefits is the removal of a potential site of disease recurrence.

We performed this observational study to evaluate primarily the morbidity and mortality related to TPP performed during CRS. We also evaluated the impact of this surgery on the site of recurrence of different PSM, essentially the ovarian cancer.

## 2. Methods

### 2.1 Study design

We conducted a retrospective and descriptive cohort study in a French tertiary cancer institution (Centre Oscar

<figure><img src="image_2.png" /></figure>

<footnote n="1">¹Department of gynecologic oncology, Centre Oscar Lambret, 59000 Lille, France</footnote>

<footnote n="2">²Université Lille, Inserm, U-1192, Laboratoire Protéomique, Réponse Inflammatoire et Spectrométrie de Masse-PRISM, 59650 Villeneuve d'Ascq, France</footnote>

<footnote>*Correspondence: ralphsaadeh@gmail.com (Ralph Saadeh)</footnote>

<footnote>Academic Editor: Enrique Hernandez</footnote>

<footnote>Submitted: 3 November 2021</footnote>

<footnote>Revised: 11 December 2021</footnote>

<footnote>Accepted: 15 December 2021</footnote>

<footnote>Published: 15 February 2022</footnote>
*Original Research*

# Total parietal peritonectomy for 61 patients: a retrospective study

Ralph Saadeh<fnref n="1" />,*, Angélique Berthet<fnref n="1" />, Séverine Marchant<fnref n="1" />, François Kraus<fnref n="1" />, Othman Aissaoui<fnref n="1" />, Fabrice Narducci<fnref n="1" />,<fnref n="2" />, Eric Leblanc<fnref n="1" />,<fnref n="2" />, Délphine Hudry<fnref n="1" />,<fnref n="2" />

## Abstract

**Objective:** To evaluate the morbidity of total parietal peritonectomy (TPP) during cytoreduction surgery, and its impact on the site of recurrence of different peritoneal surface malignancies (PSM). **Methods:** We led a retrospective study in a French tertiary cancer institution (Centre Oscar Lambret - Lille) experienced in treating PSM over a 6-year period from 2012 to 2018. All patients underwent a total parietal peritonectomy during a debulking surgery for PSM including ovarian cancer, appendiceal pseudomyxoma peritonei or peritoneal mesothelioma. **Results:** Among the 61 patients included in this study, 49 patients (80.3%) had an ovarian cancer. The rate of complete tumor resection reached 86.9% with almost 69% of surgeries being highly complex. 73.8% were transfused during the surgical procedure. The median length of hospital stay was 10 days including 7 days in Intensive Care Unit. Overall, 19 patients (31.1%) had an early postoperative complication, including 3 with a grade IIIB complication of Clavien Dindo classification. With a median follow-up of 30 months, the estimated disease-free survival in the ovarian cancer subgroup who had an initial peritonectomy (n = 42) was 84.7% at 1 year and 12.0% at 3 year. The main site of first and second recurrence was peritoneal (42% and 14%). **Conclusion:** TPP is a safe surgical procedure to treat peritoneal surface malignancies and their recurrences with a low rate of grade IIIB morbidity and no treatment-related death and allow optimal surgery. In this study there is no atypical recurrence site, such as abdominal muscle involvement.

**Keywords:** Ovarian cancer; Peritonectomy; Primary surgery debulking; Interval debulking surgery; Neo-adjuvant chemotherapy

## 1. Introduction

Peritonectomy has been used for the treatment of peritoneal surface malignancies (PSM) including colorectal cancer [1,2], appendiceal pseudomyxoma peritonei [3], and peritoneal mesothelioma [4]. Baratti et al. [5] was the first to evaluate the concept of total parietal peritonectomy (TPP) in peritoneal mesothelioma. Pelvic peritonectomy has been applied in advanced ovarian cancer with peritoneal carcinomatosis and has increased the rate of complete cytoreduction up to 60% [6].

As a technique, peritonectomy has been described and standardized first by Sugarbaker in 1995 [7] for colon cancer then modified by other groups depending on histopathology [8]. According to Sugarbaker [9], only abnormal peritoneum should be excised. But the extensive resection of tumors showed contradictory outcomes. Kyriazanos et al. [10], described the “cocoon technique” a standardized approach to achieve total extraperitoneal peritonectomy. Usually coupled with Hyperthermic Intraperitoneal Chemoperfusion (HIPEC), extensive cytoreduction surgery (CRS) has been criticized for its morbidity and mortality rates along with its benefits for all patients [11]. On the other hand, other studies have shown significant improvements in rates of survival and acceptable rates of morbidity [12,13].

In order to obtain an optimal cytoreduction, surgeons perform a TTP to resect all visible disease, since any residual disease represents a potential risk for recurrence, especially in chemo-resistant tumors.

However, removing only visible residual disease following neoadjuvant chemotherapy (NACT) and not “normally appearing peritoneum” that was previously affected before chemotherapy, showed a high rate of recurrence of 70% with the commonest site being the peritoneum, at previous disease sites [14]. Therefore, it may be hypothesized that complete removal of the peritoneum affected prior to NACT may prevent or delay the recurrence in these patients.

Another hypothesis of the TPP benefits is the removal of a potential site of disease recurrence.

We performed this observational study to evaluate primarily the morbidity and mortality related to TPP performed during CRS. We also evaluated the impact of this surgery on the site of recurrence of different PSM, essentially the ovarian cancer.

## 2. Methods

### 2.1 Study design

We conducted a retrospective and descriptive cohort study in a French tertiary cancer institution (Centre Oscar

<figure><img src="image_2.png" /></figure>

<footnote n="1">¹Department of gynecologic oncology, Centre Oscar Lambret, 59000 Lille, France</footnote>

<footnote n="2">²Université Lille, Inserm, U-1192, Laboratoire Protéomique, Réponse Inflammatoire et Spectrométrie de Masse-PRISM, 59650 Villeneuve d'Ascq, France</footnote>

<footnote>*Correspondence: ralphsaadeh@gmail.com (Ralph Saadeh)</footnote>

<footnote>Academic Editor: Enrique Hernandez</footnote>

<footnote>Submitted: 3 November 2021</footnote>

<footnote>Revised: 11 December 2021</footnote>

<footnote>Accepted: 15 December 2021</footnote>

<footnote>Published: 15 February 2022</footnote>
<table><caption>Table 1. Patient characteristics.</caption><thead><tr><th></th><th>n (%) or median (range)</th></tr></thead><tbody><tr><td>Total population, n = 61</td><td></td></tr><tr><td>Age at diagnosis:</td><td>61.9 (28.9–80.0)</td></tr><tr><td>Body Mass Index:</td><td>24.2 (17.4–44.5)</td></tr><tr><td>WHO performance status:</td><td></td></tr><tr><td>0</td><td>50 (82)</td></tr><tr><td>1</td><td>10 (16.4)</td></tr><tr><td>2</td><td>1 (1.6)</td></tr><tr><td>Peritoneal histology:</td><td></td></tr><tr><td>Ovarian cancer</td><td>49 (80.3)</td></tr><tr><td>High-Grade serous</td><td>40</td></tr><tr><td>Low-Grade serous</td><td>1</td></tr><tr><td>Clear cell carcinoma</td><td>1</td></tr><tr><td>Endometroid</td><td>3</td></tr><tr><td>Mucinous</td><td>2</td></tr><tr><td>Carcinosarcoma</td><td>2</td></tr><tr><td>Pseudomyxoma Peritonei</td><td>8 (13.1)</td></tr><tr><td>Mesothelioma</td><td>1 (1.6)</td></tr><tr><td>Other</td><td>3 (4.9)</td></tr><tr><td>Lobular breast carcinoma</td><td>1</td></tr><tr><td>Sarcoma and High-Grade serous</td><td>2</td></tr><tr><td>Peritonectomy timing:</td><td></td></tr><tr><td>At Primary or Interval Debulking Surgery</td><td>53 (86.9)</td></tr><tr><td>At recurrence</td><td>8 (13.1)</td></tr><tr><td>Residual disease after surgery:</td><td></td></tr><tr><td>CC0</td><td>53 (86.9)</td></tr><tr><td>CC1</td><td>7 (11.5)</td></tr><tr><td>CC2</td><td>1 (1.6)</td></tr><tr><td>Time between diagnosis and peritonectomy, days:</td><td>161 (0–1714)</td></tr><tr><td>Surgeon visual diagnosis versus histology report:</td><td></td></tr><tr><td>Macroscopic and microscopic lesions</td><td>51 (83.6)</td></tr><tr><td>No macroscopic or microscopic lesions (“preventive peritonectomy”)</td><td>2 (3.2)</td></tr><tr><td>Macroscopic lesions and histology results without lesions</td><td>8 (13.1)</td></tr></tbody></table>

CC, Completeness of cytoreduction; WHO, World Health Organization.

Lambret - Lille) over a 6-year period from 2012 to 2018.

All patients included in the present study underwent a TTP during a debulking surgery for PSM and treatments were validated by the tumor-board committee. Data were collected from hospital patient files without direct interaction with the patients for the research purpose. The study protocol was approved by the institutional review board and conformed to the French ethical standards and 2008 Helsinki declaration.

## 2.2 Surgical procedures

The goal of CRS was to obtain a complete cytoreduction (no macroscopic residual disease). The disease extent was quantified using Sugarbaker's Peritoneal Cancer Index (PCI) [7]. Completeness of cytoreduction score (CC-score)

was used to describe the residual disease status.

Completeness of cytoreduction (CCR) was classified as follows: macroscopically complete (CCR-0); nearly complete: residual disease ≤2.5 mm in any region (CCR-1); or suboptimal: residual disease >2.5 mm (CCR-2). All resected specimens were submitted to pathologic examination. Tumors were histologically categorized following the World Health Organization (WHO) classification [15].

TPP was defined as removal of the complete peritoneum (pelvic, bilateral anteroparietal peritoneum, bilateral upper quadrant peritoneum) using electric cautery or blunt dissection, as described in details by Yokosu et al. [16]. A TPP was performed in three different cases. First, to resect all sites of peritoneal disease in primary debulking surgery (PDS) prior to administration of a chemother-

<figure><img src="image_3.png" /></figure>
<table><caption>Table 1. Patient characteristics.</caption><thead><tr><th></th><th>n (%) or median (range)</th></tr></thead><tbody><tr><td>Total population, n = 61</td><td></td></tr><tr><td>Age at diagnosis:</td><td>61.9 (28.9–80.0)</td></tr><tr><td>Body Mass Index:</td><td>24.2 (17.4–44.5)</td></tr><tr><td>WHO performance status:</td><td></td></tr><tr><td>0</td><td>50 (82)</td></tr><tr><td>1</td><td>10 (16.4)</td></tr><tr><td>2</td><td>1 (1.6)</td></tr><tr><td>Peritoneal histology:</td><td></td></tr><tr><td>Ovarian cancer</td><td>49 (80.3)</td></tr><tr><td>High-Grade serous</td><td>40</td></tr><tr><td>Low-Grade serous</td><td>1</td></tr><tr><td>Clear cell carcinoma</td><td>1</td></tr><tr><td>Endometroid</td><td>3</td></tr><tr><td>Mucinous</td><td>2</td></tr><tr><td>Carcinosarcoma</td><td>2</td></tr><tr><td>Pseudomyxoma Peritonei</td><td>8 (13.1)</td></tr><tr><td>Mesothelioma</td><td>1 (1.6)</td></tr><tr><td>Other</td><td>3 (4.9)</td></tr><tr><td>Lobular breast carcinoma</td><td>1</td></tr><tr><td>Sarcoma and High-Grade serous</td><td>2</td></tr><tr><td>Peritonectomy timing:</td><td></td></tr><tr><td>At Primary or Interval Debulking Surgery</td><td>53 (86.9)</td></tr><tr><td>At recurrence</td><td>8 (13.1)</td></tr><tr><td>Residual disease after surgery:</td><td></td></tr><tr><td>CC0</td><td>53 (86.9)</td></tr><tr><td>CC1</td><td>7 (11.5)</td></tr><tr><td>CC2</td><td>1 (1.6)</td></tr><tr><td>Time between diagnosis and peritonectomy, days:</td><td>161 (0–1714)</td></tr><tr><td>Surgeon visual diagnosis versus histology report:</td><td></td></tr><tr><td>Macroscopic and microscopic lesions</td><td>51 (83.6)</td></tr><tr><td>No macroscopic or microscopic lesions (“preventive peritonectomy”)</td><td>2 (3.2)</td></tr><tr><td>Macroscopic lesions and histology results without lesions</td><td>8 (13.1)</td></tr></tbody></table>

CC, Completeness of cytoreduction; WHO, World Health Organization.

Lambret - Lille) over a 6-year period from 2012 to 2018.

All patients included in the present study underwent a TTP during a debulking surgery for PSM and treatments were validated by the tumor-board committee. Data were collected from hospital patient files without direct interaction with the patients for the research purpose. The study protocol was approved by the institutional review board and conformed to the French ethical standards and 2008 Helsinki declaration.

## 2.2 Surgical procedures

The goal of CRS was to obtain a complete cytoreduction (no macroscopic residual disease). The disease extent was quantified using Sugarbaker's Peritoneal Cancer Index (PCI) [7]. Completeness of cytoreduction score (CC-score)

was used to describe the residual disease status.

Completeness of cytoreduction (CCR) was classified as follows: macroscopically complete (CCR-0); nearly complete: residual disease ≤2.5 mm in any region (CCR-1); or suboptimal: residual disease >2.5 mm (CCR-2). All resected specimens were submitted to pathologic examination. Tumors were histologically categorized following the World Health Organization (WHO) classification [15].

TPP was defined as removal of the complete peritoneum (pelvic, bilateral anteroparietal peritoneum, bilateral upper quadrant peritoneum) using electric cautery or blunt dissection, as described in details by Yokosu et al. [16]. A TPP was performed in three different cases. First, to resect all sites of peritoneal disease in primary debulking surgery (PDS) prior to administration of a chemother-

<figure><img src="image_3.png" /></figure>
apy. Second, to resect all sites of residual disease in interval
debulking surgery (IDS). And finally, to remove potential
sites of disease recurrence.

Small and scattered localizations on the visceral sur-
face were resected by local excision and/or electrocoagula-
tion. In case of massive and/or deeply infiltrating disease,
visceral resections were performed, including cholecystec-
tomy, splenectomy, sigmoid, right or total colectomy. Clin-
ically suspicious lymph nodes (para-aortic and pelvic) were
sampled and submitted to pathologic examination.

2.3 Systemic chemotherapy

All patients with ovarian cancer received at least 6 cy-
cles of a platinum compound (Carboplatin or Cisplatin) and
Taxane (Paclitaxel or Docetaxel) before and/or after surgery
depending on the resectability of the tumor.

## 2.4 Follow up and definition of recurrence

The occurrence of a recurrence was assessed by a
clinical examination completed by biological (increase
in the tumor marker CA-125), radiological examinations
(thoraco-abdominopelvic CT scan, PET-scan) and/or histo-
logical evidence if possible.

The date of diagnosis of the first recurrence was col-
lected, as well as the site of recurrence (Liver, Pleural, peri-
toneal carcinomatosis...) and the date of the latest news or
death if any.

2.5 Data collection

Consecutive patients with PSM including carcino-
matosis of gastrointestinal (colon cancer) or gynecologic
origin, mostly advanced ovarian cancer, fallopian tube and
primary peritoneal tumors such as mesothelioma (DMPM)
or pseudomyxoma peritonei, undergoing PDS or IDS with
or without intraperitoneal chemotherapy (IPC) were in-
cluded. In the ovarian subgroup, we included patients with
FIGO stage I–IV-B. Patients with stage IV-A (pleural ef-
fusion and/or lung metastasis) were operated only if they
showed complete response to systemic chemotherapy and
the cytology became negative. Patients with stage IV-B
who had resectable liver metastasis, inguinal lymph node
metastasis and spleen metastasis lesions were also included.
We only collected data for patients whose records included
complete information.

The following clinical and paraclinical items were col-
lected: age at diagnosis, body mass index (BMI), WHO per-
formance status [17], preoperative CA 125 level. The tumor
characteristics were also detailed: International Federation
of Gynaecology and Obstetrics (FIGO) [18] stage for ovar-
ian cancer, histological type [15] (serous, mucinous, en-
dometrioid, clear-cell, papillary, mixed, non-epithelial ade-
nocarcinoma, pseudomyxoma, mesothelioma and serous
borderline tumors), peritoneal disease spread according to
the PCI [7] at time of diagnosis, CRS results according to
the CCR score [7], presence or absence of micro- or macro-

scopic peritoneal lesions as long as the presence or absence
of identified genetic mutations.

Surgical characteristics at time of peritonectomy in-
cluded the Aletti Score [19] to classify the difficulty of the
procedure in High, Moderate and Low risk. The sever-
ity of postoperative complications were described using the
Clavien-Dindo classification [20] based on the therapy used
to correct them.

2.6 Statistical analysis

Analysis of all the included patients was performed.
Results were presented using descriptive statistics: num-
bers and proportions for categorical variables, and median
and ranges, for continuous variables.

Time-to-event analyses were calculated from the date
of diagnostic in patients with peritonectomy performed as
part of initial surgery and not for a recurrence. Overall sur-
vival (OS) was defined as the time interval from the date
of initial diagnosis to the date of death from any case. Pa-
tient alive were censored at the date of last news. Disease-
free survival (DFS) was defined as the time interval from
the date of initial diagnosis to the date of the first tumor
recurrence or death due to any cause. Patient alive with-
out recurrence were censored at the date of the last news.
Data for survival curves were calculated using the Kaplan
Meier method. OS and DFS were assessed according to the
histopathology but also to the context of the TPP (when un-
dergoing a debulking surgery at initial diagnosis or to treat
a recurrence). Data were analyzed using the STATA v15.0
software (Timberlake Consultants Limited, Richmond upon
Thames, UK).

3. Results

From 2004 to 2018, 61 patients underwent a TPP at
our center. Patient characteristics are summarized in Ta-
ble 1. The median age was 62 years (29–80) and 82% had a
good performance status. Eighty percent of the patients had
ovarian cancer, mainly High Grade Serous Ovarian Cancer
(HGSOC), 13% pseudomyxoma, and 2% mesothelioma.
Fifty three patients (87%) had the peritonectomy at initial
diagnosis and 8 patients (13%) had a recurrent disease with
CCR-0 resection obtained in 87% of all patients.

Forty eight patients (84.2%) had a peritonectomy for macroscopic lesions and histology confirmed the disease. Only two patients had a preventive peritonectomy, where no macroscopic lesions were visualized and pathology report did not show any lesions. On the contrary, 8 patients had a complete peritonectomy for “supposedly” macroscopic lesions and histology report came back negative.

The characteristics of the surgery are available in Ta-
ble 2. The complexity of the surgical procedures was as-
sessed using the Aletti score: 42 patients (68.9%) were clas-
sified as “high” in terms of surgical difficulties, often asso-
ciated with a more efficient debulking. The median oper-
ating time was 310 min with 82% percent having an ex-

<figure><img src="image_4.png" /></figure>
apy. Second, to resect all sites of residual disease in interval
debulking surgery (IDS). And finally, to remove potential
sites of disease recurrence.

Small and scattered localizations on the visceral sur-
face were resected by local excision and/or electrocoagula-
tion. In case of massive and/or deeply infiltrating disease,
visceral resections were performed, including cholecystec-
tomy, splenectomy, sigmoid, right or total colectomy. Clin-
ically suspicious lymph nodes (para-aortic and pelvic) were
sampled and submitted to pathologic examination.

## 2.3 Systemic chemotherapy

All patients with ovarian cancer received at least 6 cy-
cles of a platinum compound (Carboplatin or Cisplatin) and
Taxane (Paclitaxel or Docetaxel) before and/or after surgery
depending on the resectability of the tumor.

## 2.4 Follow up and definition of recurrence

The occurrence of a recurrence was assessed by a
clinical examination completed by biological (increase
in the tumor marker CA-125), radiological examinations
(thoraco-abdominopelvic CT scan, PET-scan) and/or histo-
logical evidence if possible.

The date of diagnosis of the first recurrence was col-
lected, as well as the site of recurrence (Liver, Pleural, peri-
toneal carcinomatosis...) and the date of the latest news or
death if any.

## 2.5 Data collection

Consecutive patients with PSM including carcino-
matosis of gastrointestinal (colon cancer) or gynecologic
origin, mostly advanced ovarian cancer, fallopian tube and
primary peritoneal tumors such as mesothelioma (DMPM)
or pseudomyxoma peritonei, undergoing PDS or IDS with
or without intraperitoneal chemotherapy (IPC) were in-
cluded. In the ovarian subgroup, we included patients with
FIGO stage I-IV-B. Patients with stage IV-A (pleural ef-
fusion and/or lung metastasis) were operated only if they
showed complete response to systemic chemotherapy and
the cytology became negative. Patients with stage IV-B
who had resectable liver metastasis, inguinal lymph node
metastasis and spleen metastasis lesions were also included.
We only collected data for patients whose records included
complete information.

The following clinical and paraclinical items were col-
lected: age at diagnosis, body mass index (BMI), WHO per-
formance status [17], preoperative CA 125 level. The tumor
characteristics were also detailed: International Federation
of Gynaecology and Obstetrics (FIGO) [18] stage for ovar-
ian cancer, histological type [15] (serous, mucinous, en-
dometrioid, clear-cell, papillary, mixed, non-epithelial ade-
nocarcinoma, pseudomyxoma, mesothelioma and serous
borderline tumors), peritoneal disease spread according to
the PCI [7] at time of diagnosis, CRS results according to
the CCR score [7], presence or absence of micro- or macro-

scopic peritoneal lesions as long as the presence or absence
of identified genetic mutations.

Surgical characteristics at time of peritonectomy in-
cluded the Aletti Score [19] to classify the difficulty of the
procedure in High, Moderate and Low risk. The sever-
ity of postoperative complications were described using the
Clavien-Dindo classification [20] based on the therapy used
to correct them.

## 2.6 Statistical analysis

Analysis of all the included patients was performed.
Results were presented using descriptive statistics: num-
bers and proportions for categorical variables, and median
and ranges, for continuous variables.

Time-to-event analyses were calculated from the date
of diagnostic in patients with peritonectomy performed as
part of initial surgery and not for a recurrence. Overall sur-
vival (OS) was defined as the time interval from the date
of initial diagnosis to the date of death from any case. Pa-
tient alive were censored at the date of last news. Disease-
free survival (DFS) was defined as the time interval from
the date of initial diagnosis to the date of the first tumor
recurrence or death due to any cause. Patient alive with-
out recurrence were censored at the date of the last news.
Data for survival curves were calculated using the Kaplan
Meier method. OS and DFS were assessed according to the
histopathology but also to the context of the TPP (when un-
dergoing a debulking surgery at initial diagnosis or to treat
a recurrence). Data were analyzed using the STATA v15.0
software (Timberlake Consultants Limited, Richmond upon
Thames, UK).

## 3. Results

From 2004 to 2018, 61 patients underwent a TPP at
our center. Patient characteristics are summarized in Ta-
ble 1. The median age was 62 years (29-80) and 82% had a
good performance status. Eighty percent of the patients had
ovarian cancer, mainly High Grade Serous Ovarian Cancer
(HGSOC), 13% pseudomyxoma, and 2% mesothelioma.
Fifty three patients (87%) had the peritonectomy at initial
diagnosis and 8 patients (13%) had a recurrent disease with
CCR-0 resection obtained in 87% of all patients.

Forty eight patients (84.2%) had a peritonectomy for
macroscopic lesions and histology confirmed the disease.
Only two patients had a preventive peritonectomy, where
no macroscopic lesions were visualized and pathology re-
port did not show any lesions. On the contrary, 8 patients
had a complete peritonectomy for "supposedly" macro-
scopic lesions and histology report came back negative.

The characteristics of the surgery are available in Ta-
ble 2. The complexity of the surgical procedures was as-
sessed using the Aletti score: 42 patients (68.9%) were clas-
sified as “high” in terms of surgical difficulties, often asso-
ciated with a more efficient debulking. The median oper-
ating time was 310 min with 82% percent having an ex-

<figure><img src="image_4.png" /></figure>
traperitoneal peritonectomy and 66.7% lymphadenectomy. Eighteen patients (32.7%) had at least one complication during their surgery with the most common being bleeding (55.6%). Other complications were pleural (22.2%), ureter or bladder (16.7%) and digestive injuries (5.6%). The median blood loss was around 1200 mL with forty-five patients (73.8%) being transfused during the operating time.

<table><caption>**Table 2.** Surgical characteristics at time of peritonectomy (n = 61).</caption><thead><tr><th></th><th>n (%)</th></tr></thead><tbody><tr><td>Surgery characteristics</td><td></td></tr><tr><td>Extraperitoneal peritonectomy:</td><td>50 (82)</td></tr><tr><td>Lymphadenectomy:</td><td>38 (66.7)</td></tr><tr><td>Aletti Score:</td><td></td></tr><tr><td>High</td><td>42 (68.9)</td></tr><tr><td>Intermediate</td><td>19 (31.1)</td></tr><tr><td>Low</td><td>0 (0)</td></tr><tr><td>Estimated Blood Loss (mL): median (range)</td><td>1200 (50–4000)</td></tr><tr><td>Transfusion:</td><td></td></tr><tr><td>No</td><td>16 (26.2)</td></tr><tr><td>Yes</td><td>45 (73.8)</td></tr><tr><td>Packed red blood cells transfused</td><td></td></tr><tr><td>0</td><td>16 (26.2)</td></tr><tr><td>≤3</td><td>32 (52.5)</td></tr><tr><td>≤6</td><td>12 (19.7)</td></tr><tr><td>8</td><td>1 (1.6)</td></tr><tr><td>Fresh Frozen Plasma transfused</td><td></td></tr><tr><td>0</td><td>56 (91.8)</td></tr><tr><td>2–3</td><td>5 (8.2)</td></tr><tr><td>Per-operative complications:</td><td></td></tr><tr><td>No</td><td>37 (67.3)</td></tr><tr><td>Yes</td><td>18 (32.7)</td></tr><tr><td>Vascular or spleen injury</td><td>10 (18.2)</td></tr><tr><td>Pleural injury</td><td>4 (7.3)</td></tr><tr><td>Bladder injury</td><td>3 (5.3)</td></tr><tr><td>Sigmoid injury</td><td>1 (1.8)</td></tr><tr><td>Operative time (min): median (range)</td><td>310 (120–570)</td></tr></tbody></table>

The median hospitalization stay after the surgery was 10 days (6–50), including 7 days (2–17) in Intensive Care Unit (ICU) with a median parenteral nutrition of 6 days (2–21). The early post-operative complications affected 19 patients (31.1%) and are detailed in Table 3. The main complications were medical complications like infections, renal failure, etc (11.5%), wound dehiscence and evisceration (6.6%) and lymphoceles (6.6%). Three patients were re-operated: one for a leakage from a bowel anastomosis complicated by peritonitis, one for a subphrenic abscess and one for internal bleeding. Other complications were in terms of frequency: parietal wall infection (3.3%), thromboembolism (1.6%) and bleeding (1.6%).

In the ovarian cancer subgroup who had an initial peritonectomy (n = 42), Table 4, almost 73.8% of patients had a FIGO stage IIIC, 7.1% stage IVA and 16.7% stage IVB. At time of diagnosis, the median of CA125 was 1236 UI/L (8–30780) and 69% had ascites whereas only 16.7% had it at time of peritonectomy. With a median PCI of 20 (6–39) at the time of diagnosis, 54.8% of patients received a NACT before undergoing an IDS in order to optimize the cytoreduction of the cancer.

Among all patients, 32 (54.1%) had a recurrence (Table 5) of their cancer, 29 in the ovarian subgroup and 3 in the Pseudomyxoma Peritonei subgroup. Out of 49 patients in the ovarian subgroup, 21 had a peritoneal recurrence (42%), 10 had distant metastasis (20%) and 3 lymph nodes recurrence (6%). Of them, 9 patients had a second recurrence after treating the first one. Again, the predilection of recurrence was peritoneal (14%), distant metastasis (6%) and lymph node (4%). Only 2 patients (4%) had a third recurrence with peritoneal lesions in all of them. The only patient who had a preventive peritonectomy during IDS did not have any per- or post-operative complications but had a liver recurrence without peritoneal lesions after almost 1 year.

In Table 6, HIPEC regimens and site of recurrences were detailed. Different HIPEC protocols were used depending on the histology studies: irinotecan and oxaliplatin heated to 42–43 °C for 30–40 min for pseudomyxoma, endometrioid carcinoma and mucinous carcinoma, cisplatin and doxorubicin heated to 41–43 °C for 60–90 min for mesothelioma and cisplatin heated to 40–42 °C for 90 min for high-grade serous adenocarcinoma. Two patients with pseudomyxoma were given mitomycin C because of a higher risk of bleeding and allergy. Patients who received the irinotecan and oxaliplatin protocol were also given an infusion of 5-fluorouracil (5-FU) along with folinic acid 1 hour prior to HIPEC. Patients who received the Cisplatin protocol were given an IV perfusion of sodium thiosulfate for renal protection.

In the ovarian subgroup who had an initial peritonectomy, 8 patients had an IPC during surgery: 5 HGSOC, 2 mucinous and 1 endometrioid ovarian cancer. All patients had a FIGO stage IIIC. Only 2 patients had a Grade 3 complication in the postoperative period: one patient with an infected lymphocele drained under CT-Scan guidance and one patient re-operated for post-operative bleeding. Five patients had a recurrence out of 8:1 peritoneal and 3 at the level of lymph nodes and 1 patient died 2 months after surgery from general status alteration with liver and lung metastasis.

At a median follow-up of 30 months (95% Confidential Interval (CI): 23–38 months), 12 deaths occurred in the whole cohort (n = 61). In the ovarian subgroup, 23 recurrences occurred leading to death in 6 patients. In this group, the median DFS was 19.1 months (15.5–26.6 months) with

<figure><img src="image_5.png" /></figure>
traperitoneal peritonectomy and 66.7% lymphadenectomy. Eighteen patients (32.7%) had at least one complication during their surgery with the most common being bleeding (55.6%). Other complications were pleural (22.2%), ureter or bladder (16.7%) and digestive injuries (5.6%). The median blood loss was around 1200 mL with forty-five patients (73.8%) being transfused during the operating time.

<table><caption>Table 2. Surgical characteristics at time of peritonectomy (n = 61).</caption><thead><tr><th></th><th>n (%)</th></tr></thead><tbody><tr><td>Surgery characteristics</td><td></td></tr><tr><td>Extraperitoneal peritonectomy:</td><td>50 (82)</td></tr><tr><td>Lymphadenectomy:</td><td>38 (66.7)</td></tr><tr><td>Aletti Score:</td><td></td></tr><tr><td>High</td><td>42 (68.9)</td></tr><tr><td>Intermediate</td><td>19 (31.1)</td></tr><tr><td>Low</td><td>0 (0)</td></tr><tr><td>Estimated Blood Loss (mL): median (range)</td><td>1200 (50–4000)</td></tr><tr><td>Transfusion:</td><td></td></tr><tr><td>No</td><td>16 (26.2)</td></tr><tr><td>Yes</td><td>45 (73.8)</td></tr><tr><td>Packed red blood cells transfused</td><td></td></tr><tr><td>0</td><td>16 (26.2)</td></tr><tr><td>≤3</td><td>32 (52.5)</td></tr><tr><td>≤6</td><td>12 (19.7)</td></tr><tr><td>8</td><td>1 (1.6)</td></tr><tr><td>Fresh Frozen Plasma transfused</td><td></td></tr><tr><td>0</td><td>56 (91.8)</td></tr><tr><td>2–3</td><td>5 (8.2)</td></tr><tr><td>Per-operative complications:</td><td></td></tr><tr><td>No</td><td>37 (67.3)</td></tr><tr><td>Yes</td><td>18 (32.7)</td></tr><tr><td>Vascular or spleen injury</td><td>10 (18.2)</td></tr><tr><td>Pleural injury</td><td>4 (7.3)</td></tr><tr><td>Bladder injury</td><td>3 (5.3)</td></tr><tr><td>Sigmoid injury</td><td>1 (1.8)</td></tr><tr><td>Operative time (min): median (range)</td><td>310 (120–570)</td></tr></tbody></table>

The median hospitalization stay after the surgery was 10 days (6–50), including 7 days (2–17) in Intensive Care Unit (ICU) with a median parenteral nutrition of 6 days (2–21). The early post-operative complications affected 19 patients (31.1%) and are detailed in Table 3. The main complications were medical complications like infections, renal failure, etc (11.5%), wound dehiscence and evisceration (6.6%) and lymphoceles (6.6%). Three patients were re-operated: one for a leakage from a bowel anastomosis complicated by peritonitis, one for a subphrenic abscess and one for internal bleeding. Other complications were in terms of frequency: parietal wall infection (3.3%), thromboembolism (1.6%) and bleeding (1.6%).

In the ovarian cancer subgroup who had an initial peritonectomy (n = 42), Table 4, almost 73.8% of patients had a FIGO stage IIIC, 7.1% stage IVA and 16.7% stage IVB. At time of diagnosis, the median of CA125 was 1236 UI/L (8–30780) and 69% had ascites whereas only 16.7% had it at time of peritonectomy. With a median PCI of 20 (6–39) at the time of diagnosis, 54.8% of patients received a NACT before undergoing an IDS in order to optimize the cytoreduction of the cancer.

Among all patients, 32 (54.1%) had a recurrence (Table 5) of their cancer, 29 in the ovarian subgroup and 3 in the Pseudomyxoma Peritonei subgroup. Out of 49 patients in the ovarian subgroup, 21 had a peritoneal recurrence (42%), 10 had distant metastasis (20%) and 3 lymph nodes recurrence (6%). Of them, 9 patients had a second recurrence after treating the first one. Again, the predilection of recurrence was peritoneal (14%), distant metastasis (6%) and lymph node (4%). Only 2 patients (4%) had a third recurrence with peritoneal lesions in all of them. The only patient who had a preventive peritonectomy during IDS did not have any per- or post-operative complications but had a liver recurrence without peritoneal lesions after almost 1 year.

In Table 6, HIPEC regimens and site of recurrences were detailed. Different HIPEC protocols were used depending on the histology studies: irinotecan and oxaliplatin heated to 42–43 °C for 30–40 min for pseudomyxoma, endometrioid carcinoma and mucinous carcinoma, cisplatin and doxorubicin heated to 41–43 °C for 60–90 min for mesothelioma and cisplatin heated to 40–42 °C for 90 min for high-grade serous adenocarcinoma. Two patients with pseudomyxoma were given mitomycin C because of a higher risk of bleeding and allergy. Patients who received the irinotecan and oxaliplatin protocol were also given an infusion of 5-fluorouracil (5-FU) along with folinic acid 1 hour prior to HIPEC. Patients who received the Cisplatin protocol were given an IV perfusion of sodium thiosulfate for renal protection.

In the ovarian subgroup who had an initial peritonectomy, 8 patients had an IPC during surgery: 5 HGSOC, 2 mucinous and 1 endometrioid ovarian cancer. All patients had a FIGO stage IIIC. Only 2 patients had a Grade 3 complication in the postoperative period: one patient with an infected lymphocele drained under CT-Scan guidance and one patient re-operated for post-operative bleeding. Five patients had a recurrence out of 8:1 peritoneal and 3 at the level of lymph nodes and 1 patient died 2 months after surgery from general status alteration with liver and lung metastasis.

At a median follow-up of 30 months (95% Confidential Interval (CI): 23–38 months), 12 deaths occurred in the whole cohort (n = 61). In the ovarian subgroup, 23 recurrences occurred leading to death in 6 patients. In this group, the median DFS was 19.1 months (15.5–26.6 months) with

<figure><img src="image_5.png" /></figure>
<table><caption>Table 3. Post-operative complications (n = 61).</caption><thead><tr><th>Postoperative characteristics</th><th>n (%) or median (range)</th></tr></thead><tbody><tr><td>Intensive Care Unit stay, days:</td><td>7 (2–17)</td></tr><tr><td>Parenteral feedings, days:</td><td>6 (2–21)</td></tr><tr><td>Hospital stay, days:</td><td>10 (6–50)</td></tr><tr><td>Postoperative complications (&le;30 days):</td><td></td></tr><tr><td>No</td><td>42 (68.9)</td></tr><tr><td>Yes</td><td>19 (31.1)</td></tr><tr><td>Type of complications</td><td></td></tr><tr><td>Wound dehiscence and evisceration</td><td>4 (6.6)</td></tr><tr><td>Hemoperitoneum</td><td>1 (1.6)</td></tr><tr><td>Medical complications</td><td>7 (11.5)</td></tr><tr><td>Lymphocele</td><td>4 (6.6)</td></tr><tr><td>Thromboembolism</td><td>1 (1.6)</td></tr><tr><td>Parietal wall infection</td><td>2 (3.3)</td></tr><tr><td>Treatment of complications (Clavien-Dindo Classification)</td><td></td></tr><tr><td>I</td><td>2 (10.5)</td></tr><tr><td>II</td><td>9 (47.3)</td></tr><tr><td>IIIA</td><td>5 (26.3)</td></tr><tr><td>IIIB</td><td>3 (15.8)</td></tr><tr><td>IV</td><td>0 (0)</td></tr></tbody></table>

<table><caption>Table 4. Clinical characteristics for “Initial peritonectomy” group for Ovarian cancer (n = 42).</caption><thead><tr><th>Characteristics</th><th>N (%) or median (range)</th></tr></thead><tbody><tr><td>FIGO stage</td><td></td></tr><tr><td>IIB</td><td>1 (2.4)</td></tr><tr><td>IIIC</td><td>31 (73.8)</td></tr><tr><td>IVA</td><td>3 (7.1)</td></tr><tr><td>IVB</td><td>7 (16.7)</td></tr><tr><td>CA-125 at time of diagnosis (UI/mL)</td><td>1236 (8–30780)</td></tr><tr><td>Ascites at diagnosis:</td><td>29 (69)</td></tr><tr><td>Ascites at time of peritonectomy:</td><td>7 (16.7)</td></tr><tr><td>Number of NACT cycles before peritonectomy:</td><td>6 (0–12)</td></tr><tr><td>PCI at diagnosis:</td><td>20 (6–39)</td></tr><tr><td>PCI at time of peritonectomy:</td><td>15 (0–26)</td></tr><tr><td>Timing for surgery:</td><td></td></tr><tr><td>Primary debulking surgery</td><td>14 (33.3)</td></tr><tr><td>Interval debulking surgery</td><td>28 (66.7)</td></tr><tr><td>Number of adjuvant chemotherapy cycles after peritonectomy</td><td>2 (0–8)</td></tr><tr><td>Type of chemotherapy</td><td></td></tr><tr><td>Carboplatin + Paclitaxel</td><td>32</td></tr><tr><td>Carboplatin + Paclitaxel then Avastin</td><td>3</td></tr><tr><td>Carboplatin + Docetaxel</td><td>1</td></tr><tr><td>Carboplatin + Caelyx then Carboplatin + Docetaxel</td><td>1</td></tr><tr><td>Cisplatin + Paclitaxel then Carboplatin + Paclitaxel</td><td>1</td></tr><tr><td>Carboplatin + Paclitaxel + Folfox then Folfiri</td><td>1</td></tr></tbody></table>

NACT, Neoadjuvant chemotherapy; PCI, Peritoneal Cancer Index.
<table><caption>Table 3. Post-operative complications (n = 61).</caption><thead><tr><th>Postoperative characteristics</th><th>n (%) or median (range)</th></tr></thead><tbody><tr><td>Intensive Care Unit stay, days:</td><td>7 (2–17)</td></tr><tr><td>Parenteral feedings, days:</td><td>6 (2–21)</td></tr><tr><td>Hospital stay, days:</td><td>10 (6–50)</td></tr><tr><td>Postoperative complications (&le;30 days):</td><td></td></tr><tr><td>No</td><td>42 (68.9)</td></tr><tr><td>Yes</td><td>19 (31.1)</td></tr><tr><td>Type of complications</td><td></td></tr><tr><td>Wound dehiscence and evisceration</td><td>4 (6.6)</td></tr><tr><td>Hemoperitoneum</td><td>1 (1.6)</td></tr><tr><td>Medical complications</td><td>7 (11.5)</td></tr><tr><td>Lymphocele</td><td>4 (6.6)</td></tr><tr><td>Thromboembolism</td><td>1 (1.6)</td></tr><tr><td>Parietal wall infection</td><td>2 (3.3)</td></tr><tr><td>Treatment of complications (Clavien-Dindo Classification)</td><td></td></tr><tr><td>I</td><td>2 (10.5)</td></tr><tr><td>II</td><td>9 (47.3)</td></tr><tr><td>IIIA</td><td>5 (26.3)</td></tr><tr><td>IIIB</td><td>3 (15.8)</td></tr><tr><td>IV</td><td>0 (0)</td></tr></tbody></table>

<table><caption>Table 4. Clinical characteristics for “Initial peritonectomy” group for Ovarian cancer (n = 42).</caption><thead><tr><th>Characteristics</th><th>N (%) or median (range)</th></tr></thead><tbody><tr><td>FIGO stage</td><td></td></tr><tr><td>IIB</td><td>1 (2.4)</td></tr><tr><td>IIIC</td><td>31 (73.8)</td></tr><tr><td>IVA</td><td>3 (7.1)</td></tr><tr><td>IVB</td><td>7 (16.7)</td></tr><tr><td>CA-125 at time of diagnosis (UI/mL)</td><td>1236 (8–30780)</td></tr><tr><td>Ascites at diagnosis:</td><td>29 (69)</td></tr><tr><td>Ascites at time of peritonectomy:</td><td>7 (16.7)</td></tr><tr><td>Number of NACT cycles before peritonectomy:</td><td>6 (0–12)</td></tr><tr><td>PCI at diagnosis:</td><td>20 (6–39)</td></tr><tr><td>PCI at time of peritonectomy:</td><td>15 (0–26)</td></tr><tr><td>Timing for surgery:</td><td></td></tr><tr><td>Primary debulking surgery</td><td>14 (33.3)</td></tr><tr><td>Interval debulking surgery</td><td>28 (66.7)</td></tr><tr><td>Number of adjuvant chemotherapy cycles after peritonectomy</td><td>2 (0–8)</td></tr><tr><td>Type of chemotherapy</td><td></td></tr><tr><td>Carboplatin + Paclitaxel</td><td>32</td></tr><tr><td>Carboplatin + Paclitaxel then Avastin</td><td>3</td></tr><tr><td>Carboplatin + Docetaxel</td><td>1</td></tr><tr><td>Carboplatin + Caelyx then Carboplatin + Docetaxel</td><td>1</td></tr><tr><td>Cisplatin + Paclitaxel then Carboplatin + Paclitaxel</td><td>1</td></tr><tr><td>Carboplatin + Paclitaxel + Folfox then Folfiri</td><td>1</td></tr></tbody></table>

NACT, Neoadjuvant chemotherapy; PCI, Peritoneal Cancer Index.
<table><caption>Table 5. Localization of recurrences in the ovarian cancer and pseudomyxoma peritonei subgroups (N = 57).</caption><thead><tr><th>Characteristics of recurrences in the Ovarian subgroup</th><th>N (%)</th></tr></thead><tbody><tr><td>Localization of 1st recurrence (N = 28)</td><td></td></tr><tr><td>Abdominal</td><td>21 (42)</td></tr><tr><td>Retroperitoneal (Lymph nodes)</td><td>3 (6)</td></tr><tr><td>Distant Metastasis (Bones, Lungs, Pleura, Liver)</td><td>10 (20)</td></tr><tr><td>Other (CA125 elevation)</td><td>1 (2)</td></tr><tr><td>Localization of 2nd recurrence (N = 9)</td><td></td></tr><tr><td>Abdominal</td><td>7 (14)</td></tr><tr><td>Retroperitoneal (Lymph nodes)</td><td>2 (4)</td></tr><tr><td>Distant Metastasis (Lungs, Pleura, Liver)</td><td>3 (6)</td></tr><tr><td>Digestive</td><td>1 (2)</td></tr><tr><td>Localization of 3rd recurrence (N = 2)</td><td></td></tr><tr><td>Abdominal</td><td>2 (4)</td></tr><tr><td>Characteristics of recurrences in the Pseudomyxoma Peritonei subgroup</td><td></td></tr><tr><td>Localization of 1st recurrence (N = 3)</td><td></td></tr><tr><td>Abdominal</td><td>2 (25)</td></tr><tr><td>Distant Metastasis (Bones, Lungs, Pleura, Liver)</td><td>1 (12.5)</td></tr><tr><td>Localization of 2nd recurrence (N = 2)</td><td></td></tr><tr><td>Abdominal</td><td>2 (25)</td></tr><tr><td>Distant Metastasis (Lungs, Pleura, Liver)</td><td>1 (12.5)</td></tr><tr><td>Localization of 3rd recurrence (N = 1)</td><td></td></tr><tr><td>Abdominal</td><td>1 (12.5)</td></tr></tbody></table>

a 3-year overall survival of 77% (54%–90%).

## 4. Discussion

Over the last decades, concepts about the treatment of PSM and specifically advanced-stage ovarian cancer have evolved. The optimal surgical treatment has changed over time from residual tumour of less than 1 cm [21] to the complete removal of all macroscopic disease with no residual tumour [22,23], even in selected recurrence cases [24,25]. This change was independently associated with better overall survival and disease-free survival. Even though systematic complete peritonectomy is not usually recommended unless there is a widespread peritoneal involvement, it can be a necessary step for optimal surgery except in colorectal and gastric cancer carcinomatosis, where high-volume disease is a common contraindication for treatment.

Since a visual examination concurred in only 8% with the final pathologic findings, a macroscopically normal peritoneum (no obvious residual tumor) may hide a tumor beneath it with up to 50% in the region surrounding the tumor nodule and 35% in uninvolved regions [26]. According to Baratti et al. [5], selective peritonectomy of macroscopically involved peritoneum resulted in 50% of patients with residual tumour remaining on parietal surfaces. Sinukumar et al. [27] in the INDESPO study found residual disease in 23.3% of the patients with normal-looking areas of the peritoneum in the IDS. In our study, we could not study this no-

tion, since we did a complete peritonectomy regardless of visual assessment. But on the contrary, 12% of supposedly affected lesions, were histologically normal.

Complete peritonectomy was associated with high morbidity (about 40%) and significant mortality (around 4%), especially when combined with visceral resection, and even in experienced hands. In a German study, the rate of postoperative complications for the same surgical technique was 54.5%, higher than the rate in our study [28]. In our study, around 28% of patients had per-operative complications like haemorrhage, bladder injury, diaphragmatic resection and bowel injury and 74% of patients being blood transfused. After 30 days, 30% had postoperative complications with grade 3–4 morbidity observed in 11%. Our rate of complication is slightly higher than other studies like the INDEPSO study [27]. This can be explained partly by the complexity of the surgery represented by the high Aletti Score in 69% of patients. The same reason can also explain the long median ICU stay (7 days) and median parenteral feeding duration (8 days).

In the ovarian cancer group, the overall survival was 77% at 3 years and the median disease-free survival was 19.1 months (15.5–26.6). Compared to other studies, like Vergote et al. [29] and Bakrin et al. [30], our patients did not have a worse overall survival. Bakrin et al. had a median OS of 35.4 months and Vergote et al. of 29–30 months in PDS and IDS groups respectively. In the LION trial [31]

<figure><img src="image_6.png" /></figure>
<table><caption>Table 5. Localization of recurrences in the ovarian cancer and pseudomyxoma peritonei subgroups (N = 57).</caption><thead><tr><th>Characteristics of recurrences in the Ovarian subgroup</th><th>N (%)</th></tr></thead><tbody><tr><td>Localization of 1st recurrence (N = 28)</td><td></td></tr><tr><td>Abdominal</td><td>21 (42)</td></tr><tr><td>Retroperitoneal (Lymph nodes)</td><td>3 (6)</td></tr><tr><td>Distant Metastasis (Bones, Lungs, Pleura, Liver)</td><td>10 (20)</td></tr><tr><td>Other (CA125 elevation)</td><td>1 (2)</td></tr><tr><td>Localization of 2nd recurrence (N = 9)</td><td></td></tr><tr><td>Abdominal</td><td>7 (14)</td></tr><tr><td>Retroperitoneal (Lymph nodes)</td><td>2 (4)</td></tr><tr><td>Distant Metastasis (Lungs, Pleura, Liver)</td><td>3 (6)</td></tr><tr><td>Digestive</td><td>1 (2)</td></tr><tr><td>Localization of 3rd recurrence (N = 2)</td><td></td></tr><tr><td>Abdominal</td><td>2 (4)</td></tr><tr><td>Characteristics of recurrences in the Pseudomyxoma Peritonei subgroup</td><td></td></tr><tr><td>Localization of 1st recurrence (N = 3)</td><td></td></tr><tr><td>Abdominal</td><td>2 (25)</td></tr><tr><td>Distant Metastasis (Bones, Lungs, Pleura, Liver)</td><td>1 (12.5)</td></tr><tr><td>Localization of 2nd recurrence (N = 2)</td><td></td></tr><tr><td>Abdominal</td><td>2 (25)</td></tr><tr><td>Distant Metastasis (Lungs, Pleura, Liver)</td><td>1 (12.5)</td></tr><tr><td>Localization of 3rd recurrence (N = 1)</td><td></td></tr><tr><td>Abdominal</td><td>1 (12.5)</td></tr></tbody></table>

a 3-year overall survival of 77% (54%–90%).

## 4. Discussion

Over the last decades, concepts about the treatment of PSM and specifically advanced-stage ovarian cancer have evolved. The optimal surgical treatment has changed over time from residual tumour of less than 1 cm [21] to the complete removal of all macroscopic disease with no residual tumour [22,23], even in selected recurrence cases [24,25]. This change was independently associated with better overall survival and disease-free survival. Even though systematic complete peritonectomy is not usually recommended unless there is a widespread peritoneal involvement, it can be a necessary step for optimal surgery except in colorectal and gastric cancer carcinomatosis, where high-volume disease is a common contraindication for treatment.

Since a visual examination concurred in only 8% with the final pathologic findings, a macroscopically normal peritoneum (no obvious residual tumor) may hide a tumor beneath it with up to 50% in the region surrounding the tumor nodule and 35% in uninvolved regions [26]. According to Baratti et al. [5], selective peritonectomy of macroscopically involved peritoneum resulted in 50% of patients with residual tumour remaining on parietal surfaces. Sinukumar et al. [27] in the INDESPO study found residual disease in 23.3% of the patients with normal-looking areas of the peritoneum in the IDS. In our study, we could not study this no-

tion, since we did a complete peritonectomy regardless of visual assessment. But on the contrary, 12% of supposedly affected lesions, were histologically normal.

Complete peritonectomy was associated with high morbidity (about 40%) and significant mortality (around 4%), especially when combined with visceral resection, and even in experienced hands. In a German study, the rate of postoperative complications for the same surgical technique was 54.5%, higher than the rate in our study [28]. In our study, around 28% of patients had per-operative complications like haemorrhage, bladder injury, diaphragmatic resection and bowel injury and 74% of patients being blood transfused. After 30 days, 30% had postoperative complications with grade 3–4 morbidity observed in 11%. Our rate of complication is slightly higher than other studies like the INDEPSO study [27]. This can be explained partly by the complexity of the surgery represented by the high Aletti Score in 69% of patients. The same reason can also explain the long median ICU stay (7 days) and median parenteral feeding duration (8 days).

In the ovarian cancer group, the overall survival was 77% at 3 years and the median disease-free survival was 19.1 months (15.5–26.6). Compared to other studies, like Vergote et al. [29] and Bakrin et al. [30], our patients did not have a worse overall survival. Bakrin et al. had a median OS of 35.4 months and Vergote et al. of 29–30 months in PDS and IDS groups respectively. In the LION trial [31]

<figure><img src="image_6.png" /></figure>
<table><caption>Table 6. Detailed HIPEC regimens and associated complications and recurrences.</caption><thead><tr><th></th><th>Histology</th><th>IPC</th><th>T °C</th><th>Duration</th><th>FIGO</th><th>Per-operative complications</th><th>Post-operative complications</th><th>Clavien-Dindo Classification</th><th>Recurrence</th></tr></thead><tbody><tr><td>1</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>42–43 °C</td><td>35 min</td><td>IIIC</td><td>Non</td><td>Renal</td><td>2</td><td>Non</td></tr><tr><td>2</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>43 °C</td><td>30 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Abdominal + Pleural</td></tr><tr><td>3</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>42 °C</td><td>30 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Non</td></tr><tr><td>4</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>42–43 °C</td><td>30 min</td><td>IIIC</td><td>Bleeding</td><td>Non</td><td></td><td>Non</td></tr><tr><td>5</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>42–43 °C</td><td>40 min</td><td>IIIC</td><td>Non</td><td>Infection</td><td>3A</td><td>Non</td></tr><tr><td>6</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>43 °C</td><td>30 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Non</td></tr><tr><td>7</td><td>Pseudomyxoma Mitomycin1 peritonei</td><td></td><td>41 °C</td><td>90 min</td><td>IIIC</td><td>Non</td><td>Digestive</td><td>2</td><td>Non</td></tr><tr><td>8</td><td>Pseudomyxoma Mitomycin2 peritonei</td><td></td><td>42 °C</td><td>90 min</td><td>IVA</td><td>Non</td><td>Non</td><td></td><td>Non</td></tr><tr><td>9</td><td>Mesothelioma Cisplatin-Doxorubicin</td><td></td><td>41–42 °C</td><td>90 min</td><td>IIIC</td><td>Non</td><td>Pulmonary</td><td>2</td><td>Non</td></tr><tr><td>10</td><td>Mucinous ovarian cancer Irinotecan/Oxaliplatin</td><td></td><td>42–43 °C</td><td>30 min</td><td>IIIC</td><td>Bleeding</td><td>Non</td><td></td><td>Lymph nodes</td></tr><tr><td>11</td><td>Mucinous ovarian cancer Irinotecan/Oxaliplatin</td><td></td><td>43 °C</td><td>30 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Non</td></tr><tr><td>12</td><td>HGSOC Cisplatin 80 mg/m²</td><td></td><td>42 °C</td><td>60 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Abdominal</td></tr><tr><td>13</td><td>HGSOC Cisplatin 100 mg/m²</td><td></td><td>40 °C</td><td>90 min</td><td>IIIC</td><td>Urinary</td><td>Non</td><td></td><td>Lymph nodes</td></tr><tr><td>14</td><td>HGSOC Cisplatin 100 mg/m²</td><td></td><td>40 °C</td><td>90 min</td><td>IIIC</td><td>Non</td><td>Infection</td><td>3A</td><td>Non</td></tr><tr><td>15</td><td>HGSOC Cisplatin 100 mg/m²</td><td></td><td>40 °C</td><td>90 min</td><td>IIIC</td><td>Bleeding</td><td>Non</td><td></td><td>Lymph nodes</td></tr><tr><td>16</td><td>HGSOC Cisplatin 100 mg/m²</td><td></td><td>40 °C</td><td>90 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Non</td></tr><tr><td>17</td><td>Endometrioid ovarian cáncer Irinotecan/Oxaliplatin</td><td></td><td>43 °C</td><td>45 min</td><td>IIIC</td><td>Bleeding</td><td>Bleeding</td><td>3B</td><td>Liver + Lung</td></tr></tbody></table>

IPC, Intrapertoneal chemotherapy; T °C, Temperature; FIGO, International Federation of Gynaecology and Obstetrics stage; HGSOC, High-grade Serous Ovarian Cancer.

1, Hemorrhagic risk; 2, Allergy.

and Yokosu *et al.* [16] who had the same conditions as our study, the 3-year OS was 62% and 87.5% respectively.

But when comparing the DFS in our study to other studies, we notice conflicting conclusions. For example, in the INDEPSO study [27] the median DFS was 37 months, almost 18 months longer than the one we got with a CC0 rate lower than ours (60% versus 86.9%). On the contrary, Vergote *et al.* [29,32] showed shorter DFS in both studies (11.1–12 months).

We also noticed that even with a complete peritonectomy there is a predilection for abdominal recurrence as we can see in Table 5. In both ovarian and pseudomyxoma subgroups, abdominal localization was present in 42% and 25% of first recurrences respectively, 14% and 25% of second recurrences and 100% of third recurrence. Those findings are in accordance with other studies like Sinuku-

mar *et al.* (Peritoneal recurrences = 100%) [24] and Akaishi *et al.* [33] (62.5%). On the contrary, lymph node localization only formed 6% of first recurrences and 4% of second recurrences in the ovarian subgroup.

An innovative treatment for PSM - HIPEC - was developed in 1980 by Spratt [34], who reported the first case successfully treated with HIPEC. Later on, different conflicting results came from retrospective studies until a randomized controlled trial was published recently by Van Driel *et al.* [35]. This study was important because it is the best evidence to date that HIPEC can achieve significant benefits in terms of survival without excess of morbidity or loss of quality of life in advanced ovarian cancer. On the other hand, HIPEC is the recommended treatment of pseudomyxoma peritonei along with optimal surgery. Several studies confirmed the benefice of such a combination on
<table><caption>Table 6. Detailed HIPEC regimens and associated complications and recurrences.</caption><thead><tr><th></th><th>Histology</th><th>IPC</th><th>T °C</th><th>Duration</th><th>FIGO</th><th>Per-operative complications</th><th>Post-operative complications</th><th>Clavien-Dindo Classification</th><th>Recurrence</th></tr></thead><tbody><tr><td>1</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>42–43 °C</td><td>35 min</td><td>IIIC</td><td>Non</td><td>Renal</td><td>2</td><td>Non</td></tr><tr><td>2</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>43 °C</td><td>30 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Abdominal + Pleural</td></tr><tr><td>3</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>42 °C</td><td>30 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Non</td></tr><tr><td>4</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>42–43 °C</td><td>30 min</td><td>IIIC</td><td>Bleeding</td><td>Non</td><td></td><td>Non</td></tr><tr><td>5</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>42–43 °C</td><td>40 min</td><td>IIIC</td><td>Non</td><td>Infection</td><td>3A</td><td>Non</td></tr><tr><td>6</td><td>Pseudomyxoma Irinotecan/Oxaliplatin peritonei</td><td></td><td>43 °C</td><td>30 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Non</td></tr><tr><td>7</td><td>Pseudomyxoma Mitomycin1 peritonei</td><td></td><td>41 °C</td><td>90 min</td><td>IIIC</td><td>Non</td><td>Digestive</td><td>2</td><td>Non</td></tr><tr><td>8</td><td>Pseudomyxoma Mitomycin2 peritonei</td><td></td><td>42 °C</td><td>90 min</td><td>IVA</td><td>Non</td><td>Non</td><td></td><td>Non</td></tr><tr><td>9</td><td>Mesothelioma Cisplatin-Doxorubicin</td><td></td><td>41–42 °C</td><td>90 min</td><td>IIIC</td><td>Non</td><td>Pulmonary</td><td>2</td><td>Non</td></tr><tr><td>10</td><td>Mucinous ovarian cancer Irinotecan/Oxaliplatin</td><td></td><td>42–43 °C</td><td>30 min</td><td>IIIC</td><td>Bleeding</td><td>Non</td><td></td><td>Lymph nodes</td></tr><tr><td>11</td><td>Mucinous ovarian cancer Irinotecan/Oxaliplatin</td><td></td><td>43 °C</td><td>30 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Non</td></tr><tr><td>12</td><td>HGSOC Cisplatin 80 mg/m²</td><td></td><td>42 °C</td><td>60 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Abdominal</td></tr><tr><td>13</td><td>HGSOC Cisplatin 100 mg/m²</td><td></td><td>40 °C</td><td>90 min</td><td>IIIC</td><td>Urinary</td><td>Non</td><td></td><td>Lymph nodes</td></tr><tr><td>14</td><td>HGSOC Cisplatin 100 mg/m²</td><td></td><td>40 °C</td><td>90 min</td><td>IIIC</td><td>Non</td><td>Infection</td><td>3A</td><td>Non</td></tr><tr><td>15</td><td>HGSOC Cisplatin 100 mg/m²</td><td></td><td>40 °C</td><td>90 min</td><td>IIIC</td><td>Bleeding</td><td>Non</td><td></td><td>Lymph nodes</td></tr><tr><td>16</td><td>HGSOC Cisplatin 100 mg/m²</td><td></td><td>40 °C</td><td>90 min</td><td>IIIC</td><td>Non</td><td>Non</td><td></td><td>Non</td></tr><tr><td>17</td><td>Endometrioid ovarian cáncer Irinotecan/Oxaliplatin</td><td></td><td>43 °C</td><td>45 min</td><td>IIIC</td><td>Bleeding</td><td>Bleeding</td><td>3B</td><td>Liver + Lung</td></tr></tbody></table>

IPC, Intrapertoneal chemotherapy; T °C, Temperature; FIGO, International Federation of Gynaecology and Obstetrics stage; HGSOC, High-grade Serous Ovarian Cancer.

1, Hemorrhagic risk; 2, Allergy.

and Yokosu *et al.* [16] who had the same conditions as our study, the 3-year OS was 62% and 87.5% respectively.

But when comparing the DFS in our study to other studies, we notice conflicting conclusions. For example, in the INDEPSO study [27] the median DFS was 37 months, almost 18 months longer than the one we got with a CC0 rate lower than ours (60% versus 86.9%). On the contrary, Vergote *et al.* [29,32] showed shorter DFS in both studies (11.1–12 months).

We also noticed that even with a complete peritonectomy there is a predilection for abdominal recurrence as we can see in Table 5. In both ovarian and pseudomyxoma subgroups, abdominal localization was present in 42% and 25% of first recurrences respectively, 14% and 25% of second recurrences and 100% of third recurrence. Those findings are in accordance with other studies like Sinuku-

mar *et al.* (Peritoneal recurrences = 100%) [24] and Akaishi *et al.* [33] (62.5%). On the contrary, lymph node localization only formed 6% of first recurrences and 4% of second recurrences in the ovarian subgroup.

An innovative treatment for PSM - HIPEC - was developed in 1980 by Spratt [34], who reported the first case successfully treated with HIPEC. Later on, different conflicting results came from retrospective studies until a randomized controlled trial was published recently by Van Driel *et al.* [35]. This study was important because it is the best evidence to date that HIPEC can achieve significant benefits in terms of survival without excess of morbidity or loss of quality of life in advanced ovarian cancer. On the other hand, HIPEC is the recommended treatment of pseudomyxoma peritonei along with optimal surgery. Several studies confirmed the benefice of such a combination on
the survival rates [36,37]. In our study, HIPEC was used
in nineteen patients, with eight of them having an advanced
ovarian cancer and eight having pseudomyxoma peritonei.
As expected, the rate of grade 3–4 postoperative morbid-
ity in the HIPEC group (16.6%) was slightly higher than
the rest of the patients (11%). Another significant thing is
the high rate of recurrence in the ovarian subgroup which
reached 50% with a preferential site of recurrence being the
lymph nodes.

The limitations of our study are firstly linked to its ret-
rospective character. There is a potential selection-bias of
diseases associated with confounding risk factors. Another
limitation is the heterogeneity of the studied group: it in-
cluded patients with different peritoneal histology and dif-
ferent timing of surgery (initial or recurrence).

However, the strength of this study consists in the lim-
ited number of studies discussing this topic. Another strong
point is the detailed description of the morbidity and sites
of recurrence after TTP.

**5. Conclusions**

Complete peritonectomy is a feasible surgical proce-
dure to treat PSM and their recurrences with a low rate
of grade 3–4 morbidity and an acceptable operating time.
Even though it does not prevent peritoneal recurrence, this
technique did not show to be a risk factor for distant re-
currences, especially parietal wall metastasis. It should be
known and mastered by surgeons to increase the rate of op-
timal surgery which can affect the survival rates.

Author contributions

RS, AB, SM, FN, EL, DH designed the research
study. RS, AB, FK and DH performed the Data Collection.
SM and OA analyzed the data. All authors contributed to
editorial changes in the manuscript. All authors read and
approved the final manuscript.

Ethics approval and consent to participate

All subjects gave their informed consent for inclusion
before they participated in the study. The study was con-
ducted in accordance with the Declaration of Helsinki, and
the protocol was approved by the Ethics Committee of Cen-
tre Oscar Lambret (approval code: CEC-2022-001).

Acknowledgment

We would like to express our gratitude to all those who
helped us during the writing of this manuscript. Thanks to
all the peer reviewers for their opinions and suggestions.

Funding

This research received no external funding.

Conflict of interest

The authors declare no conflict of interest.

**References**

[1] Cashin PH, Mahteme H, Spång N, Syk I, Frödin JE, Torkzad M, et al. Cytoreductive surgery and intraperitoneal chemotherapy versus systemic chemotherapy for colorectal peritoneal metastases: a randomised trial. European Journal of Cancer. 2016; 53: 155–162.

[2] Verwaal VJ, Bruin S, Boot H, van Slooten G, van Tinteren H. 8-Year Follow-up of Randomized Trial: Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy Versus Systemic Chemotherapy in Patients with Peritoneal Carcinomatosis of Colorectal Cancer. Annals of Surgical Oncology. 2008; 15: 2426–2432.

[3] Ansari N, Chandrakumaran K, Dayal S, Mohamed F, Cecil TD, Moran BJ. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in 1000 patients with perforated appendiceal epithelial tumours. European Journal of Surgical Oncology. 2016; 42: 1035–1041.

[4] Baratti D, Kusamura S, Cabras AD, Bertulli R, Hutanu I, Deraco M. Diffuse malignant peritoneal mesothelioma: Long-term survival with complete cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy (HIPEC). European Journal of Cancer. 2013; 49: 3140–3148.

[5] Baratti D, Kusamura S, Cabras AD, Deraco M. Cytoreductive Surgery with Selective Versus Complete Parietal Peritonectomy Followed by Hyperthermic Intraperitoneal Chemotherapy in Patients with Diffuse Malignant Peritoneal Mesothelioma: a Controlled Study. Annals of Surgical Oncology. 2012; 19: 1416–1424.

[6] Chang SJ, Bristow RE, Chi DS, Cliby WA. Role of aggressive surgical cytoreduction in advanced ovarian cancer. Journal of Gynecologic Oncology. 2015; 26: 336–342.

[7] Jacquet P, Sugarbaker PH. Clinical research methodologies in diagnosis and staging of patients with peritoneal carcinomatosis. Cancer Treatment and Research. 1996; 82: 359–374.

[8] Deraco M, Baratti D, Kusamura S, Laterza B, Balestra MR. Surgical technique of parietal and visceral peritonectomy for peritoneal surface malignancies. Journal of Surgical Oncology. 2009; 100: 321–328.

[9] Sugarbaker PH. Management of peritoneal metastases - Basic concepts. Journal of B.U.ON. 2015; 20 Suppl 1: S2–11.

[10] Kyriazanos I, Papageorgiou D, Zoulamoglou M, Marougas M, Stamos N, Ivros N, et al. Total extraperitoneal access for parietal peritonectomy for peritoneal surface malignancy: The ‘cocoon’ technique. European Journal of Obstetrics, Gynecology, and Reproductive Biology. 2020; 251: 258–262.

[11] Mohamed F, Cecil T, Moran B, Sugarbaker P. A new standard of care for the management of peritoneal surface malignancy. Current Oncology. 2011; 18: e84–96.

[12] Harter P, Muallem ZM, Buhrmann C, Lorenz D, Kaub C, Hils R, et al. Impact of a structured quality management program on surgical outcome in primary advanced ovarian cancer. Gynecologic Oncology. 2011; 121: 615–619.

[13] Chi DS, Eisenhauer EL, Zivanovic O, Sonoda Y, Abu-Rustum NR, Levine DA, et al. Improved progression-free and overall survival in advanced ovarian cancer as a result of a change in surgical paradigm. Gynecologic Oncology. 2009; 114: 26–31.

[14] Ferrandina G, Legge F, Salutari V, Paglia A, Testa A, Scambia G. Impact of pattern of recurrence on clinical outcome of ovarian cancer patients: Clinical considerations. European Journal of Cancer. 2006; 42: 2296–302.

[15] Meinhold-Heerlein I, Fotopoulou C, Harter P, Kurzeder C, Mustea A, Wimberger P, et al. Statement by the Kommission Ovar of the AGO: The New FIGO and WHO Classifications of Ovarian, Fallopian Tube and Primary Peritoneal Cancer. Geburtshilfe und Frauenheilkunde. 2015; 75: 1021–1027.

<figure><img src="image_7.png" /></figure>
the survival rates [36,37]. In our study, HIPEC was used
in nineteen patients, with eight of them having an advanced
ovarian cancer and eight having pseudomyxoma peritonei.
As expected, the rate of grade 3–4 postoperative morbid-
ity in the HIPEC group (16.6%) was slightly higher than
the rest of the patients (11%). Another significant thing is
the high rate of recurrence in the ovarian subgroup which
reached 50% with a preferential site of recurrence being the
lymph nodes.

The limitations of our study are firstly linked to its ret-
rospective character. There is a potential selection-bias of
diseases associated with confounding risk factors. Another
limitation is the heterogeneity of the studied group: it in-
cluded patients with different peritoneal histology and dif-
ferent timing of surgery (initial or recurrence).

However, the strength of this study consists in the lim-
ited number of studies discussing this topic. Another strong
point is the detailed description of the morbidity and sites
of recurrence after TTP.

5. Conclusions

Complete peritonectomy is a feasible surgical proce-
dure to treat PSM and their recurrences with a low rate
of grade 3–4 morbidity and an acceptable operating time.
Even though it does not prevent peritoneal recurrence, this
technique did not show to be a risk factor for distant re-
currences, especially parietal wall metastasis. It should be
known and mastered by surgeons to increase the rate of op-
timal surgery which can affect the survival rates.

Author contributions

RS, AB, SM, FN, EL, DH designed the research
study. RS, AB, FK and DH performed the Data Collection.
SM and OA analyzed the data. All authors contributed to
editorial changes in the manuscript. All authors read and
approved the final manuscript.

Ethics approval and consent to participate

All subjects gave their informed consent for inclusion
before they participated in the study. The study was con-
ducted in accordance with the Declaration of Helsinki, and
the protocol was approved by the Ethics Committee of Cen-
tre Oscar Lambret (approval code: CEC-2022-001).

Acknowledgment

We would like to express our gratitude to all those who
helped us during the writing of this manuscript. Thanks to
all the peer reviewers for their opinions and suggestions.

Funding

This research received no external funding.

Conflict of interest

The authors declare no conflict of interest.

**References**

[1] Cashin PH, Mahteme H, Spång N, Syk I, Frödin JE, Torkzad M, et al. Cytoreductive surgery and intraperitoneal chemotherapy versus systemic chemotherapy for colorectal peritoneal metastases: a randomised trial. European Journal of Cancer. 2016; 53: 155–162.

[2] Verwaal VJ, Bruin S, Boot H, van Slooten G, van Tinteren H. 8-Year Follow-up of Randomized Trial: Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy Versus Systemic Chemotherapy in Patients with Peritoneal Carcinomatosis of Colorectal Cancer. Annals of Surgical Oncology. 2008; 15: 2426–2432.

[3] Ansari N, Chandrakumaran K, Dayal S, Mohamed F, Cecil TD, Moran BJ. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in 1000 patients with perforated appendiceal epithelial tumours. European Journal of Surgical Oncology. 2016; 42: 1035–1041.

[4] Baratti D, Kusamura S, Cabras AD, Bertulli R, Hutanu I, Deraco M. Diffuse malignant peritoneal mesothelioma: Long-term survival with complete cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy (HIPEC). European Journal of Cancer. 2013; 49: 3140–3148.

[5] Baratti D, Kusamura S, Cabras AD, Deraco M. Cytoreductive Surgery with Selective Versus Complete Parietal Peritonectomy Followed by Hyperthermic Intraperitoneal Chemotherapy in Patients with Diffuse Malignant Peritoneal Mesothelioma: a Controlled Study. Annals of Surgical Oncology. 2012; 19: 1416–1424.

[6] Chang SJ, Bristow RE, Chi DS, Cliby WA. Role of aggressive surgical cytoreduction in advanced ovarian cancer. Journal of Gynecologic Oncology. 2015; 26: 336–342.

[7] Jacquet P, Sugarbaker PH. Clinical research methodologies in diagnosis and staging of patients with peritoneal carcinomatosis. Cancer Treatment and Research. 1996; 82: 359–374.

[8] Deraco M, Baratti D, Kusamura S, Laterza B, Balestra MR. Surgical technique of parietal and visceral peritonectomy for peritoneal surface malignancies. Journal of Surgical Oncology. 2009; 100: 321–328.

[9] Sugarbaker PH. Management of peritoneal metastases - Basic concepts. Journal of B.U.ON. 2015; 20 Suppl 1: S2–11.

[10] Kyriazanos I, Papageorgiou D, Zoulamoglou M, Marougas M, Stamos N, Ivros N, et al. Total extraperitoneal access for parietal peritonectomy for peritoneal surface malignancy: The ‘cocoon’ technique. European Journal of Obstetrics, Gynecology, and Reproductive Biology. 2020; 251: 258–262.

[11] Mohamed F, Cecil T, Moran B, Sugarbaker P. A new standard of care for the management of peritoneal surface malignancy. Current Oncology. 2011; 18: e84–96.

[12] Harter P, Muallem ZM, Buhrmann C, Lorenz D, Kaub C, Hils R, et al. Impact of a structured quality management program on surgical outcome in primary advanced ovarian cancer. Gynecologic Oncology. 2011; 121: 615–619.

[13] Chi DS, Eisenhauer EL, Zivanovic O, Sonoda Y, Abu-Rustum NR, Levine DA, et al. Improved progression-free and overall survival in advanced ovarian cancer as a result of a change in surgical paradigm. Gynecologic Oncology. 2009; 114: 26–31.

[14] Ferrandina G, Legge F, Salutari V, Paglia A, Testa A, Scambia G. Impact of pattern of recurrence on clinical outcome of ovarian cancer patients: Clinical considerations. European Journal of Cancer. 2006; 42: 2296–302.

[15] Meinhold-Heerlein I, Fotopoulou C, Harter P, Kurzeder C, Mustea A, Wimberger P, et al. Statement by the Kommission Ovar of the AGO: The New FIGO and WHO Classifications of Ovarian, Fallopian Tube and Primary Peritoneal Cancer. Geburtshilfe und Frauenheilkunde. 2015; 75: 1021–1027.

<figure><img src="image_7.png" /></figure>
[16] Yokosu K, Tanabe H, Nomura S, Ozone H, Saito M, Takano H, et al. Total parietal peritonectomy in primary debulking surgery for advanced ovarian cancer. Gynecologic Oncology Reports. 2021; 37: 100805.

[17] Oken MM, Creech RH, Tormey DC, Horton J, Davis TE, McFadden ET, et al. Toxicity and response criteria of the Eastern Cooperative Oncology Group. American Journal of Clinical Oncology. 1982; 5: 649–655.

[18] Mutch DG, Prat J. 2014 FIGO staging for ovarian, fallopian tube and peritoneal cancer. Gynecologic Oncology. 2014; 133: 401–404.

[19] Aletti G, Santillan A, Eisenhauer E, Hu J, Aletti G, Podratz K, et al. A new frontier for quality of care in gynecologic oncology surgery: Multi-institutional assessment of short-term outcomes for ovarian cancer using a risk-adjusted model. Gynecologic Oncology. 2007; 107: 99–106.

[20] Dindo D, Demartines N, Clavien P. Classification of Surgical Complications. Annals of Surgery. 2004; 240: 205–213.

[21] Hoskins WJ, Bundy BN, Thigpen JT, Omura GA. The influence of cytoreductive surgery on recurrence-free interval and survival in small-volume Stage III epithelial ovarian cancer: a gynecologic oncology group study. Gynecologic Oncology. 1992; 47: 159–166.

[22] Elattar A, Bryant A, Winter-Roach BA, Hatem M, Naik R. Optimal primary surgical treatment for advanced epithelial ovarian cancer. The Cochrane Database of Systematic Reviews. 2011; 2011: CD007565.

[23] Chang S, Hodeib M, Chang J, Bristow RE. Survival impact of complete cytoreduction to no gross residual disease for advanced-stage ovarian cancer: a meta-analysis. Gynecologic Oncology. 2013; 130: 493–498.

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[25] Du Bois A, Vergote I, Ferron G, Reuss A, Meier W, Greggi S, et al. Randomized controlled phase III study evaluating the impact of secondary cytoreductive surgery in recurrent ovarian cancer: AGO DESKTOP III/ENGOT ov20. Journal of Clinical Oncology. 2017; 35: 5501–5501.

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[29] Vergote I, Tropé CG, Amant F, Kristensen GB, Ehlen T, Johnson N, et al. Neoadjuvant Chemotherapy or Primary Surgery in Stage IIIC or IV Ovarian Cancer. New England Journal of Medicine. 2010; 363: 943–953.

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[32] Vergote I, Coens C, Nankivell M, Kristensen GB, Parmar MKB, Ehlen T, et al. Neoadjuvant Chemotherapy Versus Debulking Surgery in Advanced Tubo-Ovarian Cancers: Pooled Analysis of Individual Patient Data from the EORTC 55971 and CHO-RUS Trials. The Lancet. Oncology. 2018; 19: 1680–1687.

[33] Akaishi E, Teixeira F, Katayama M, Mizumoto N, Costa FP, Buzaid AC, et al. Peritonectomy for Peritoneal Carcinomatosis: Long-Term Outcomes from a Single Brazilian Institution. World Journal of Surgery. 2009; 33: 835–839.

[34] Spratt JS, Adcock RA, Muskovin M, Sherrill W, McKeown J. Clinical delivery system for intraperitoneal hyperthermic chemotherapy. Cancer Research. 1980; 40: 256–260.

[35] van Driel WJ, Koole SN, Sikorska K, Schagen van Leeuwen JH, Schreuder HWR, Hermans RHM, et al. Hyperthermic Intraperitoneal Chemotherapy in Ovarian Cancer. New England Journal of Medicine. 2018; 378: 230–240.

[36] Youssef H, Newman C, Chandrakumaran K, Mohamed F, Cecil TD, Moran BJ. Operative Findings, Early Complications, and Long-Term Survival in 456 Patients with Pseudomyxoma Peritonei Syndrome of Appendiceal Origin. Diseases of the Colon & Rectum. 2011; 54: 293–299.

[37] Moran B, Baratti D, Yan TD, Kusamura S, Deraco M. Consensus statement on the loco-regional treatment of appendiceal mucinous neoplasms with peritoneal dissemination (pseudomyxoma peritonei). Journal of Surgical Oncology. 2008; 98: 277–282.