Effects of Modified Precision Functional Sphincter-Preserving Surgery (PPS) on Ultralow Rectal Cancer

Study Overview
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Brief Summary
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RATIONALE: Colorectal cancer is one of the most common cancers. However, approaches to minimize surgical trauma, preserve anal function, avoid abdominal stoma, and improve quality of life for patients with ultralow rectal cancers were limited. Thus, new technologies are urgently needed to improve the anal preservation rate, reduce the incidence of anastomotic leakage and improve postoperative anal function in patients with ultralow rectal cancer. PURPOSE: This one-arm multicenter prospective cohort study aims to collect the data of patients with ultralow rectal cancer who undergo sphincter-preserving surgeries, including modified PPS and conventional surgeries, then compare the effects of different operations on clinical outcomes and to see the efficacy and safety of modified PPS surgery when compared with conventional procedures in the treatment of ultralow rectal cancer.

Official Title
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Effects of Modified Precision Functional Sphincter-Preserving Surgery (PPS) on Ultralow Rectal Cancer: A Multicenter Prospective Cohort Study

Conditions
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Rectum Cancer, Stoma Colostomy, Faecal Incontinence, Leakage, Anastomotic

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Histological proof of newly diagnosed primary adenocarcinoma of the rectum The lower edge of tumor < 3 cm from the dentate line Clinical T stage ≤ T3 Exclusion Criteria: The lower edge of tumor < 1 cm from the dentate line Locally advanced stage of tumor Presence of metastatic disease or recurrent rectal tumor Concomitant malignancies Concurrent uncontrolled medical conditions Impaired anal function before surgery Presence of acute bowel obstruction or bowel perforation caused by cancer Pregnancy or breast feeding

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| PPS surgery<br>Patients who undergo modified PPS surgery in order to preserve anal sphincter function under the premise of radical resection of ultralow rectal cancer. | |
| Conventional<br>Patients who undergo conventional sphincter-preserving surgeries. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of temporary defunctioning stoma | The percentage of patients who get temporary defunctioning stoma to limit the consequences of anastomotic leakage. | Within 30 days after operation | 
| The percentage of patients who develop anastomotic leakage | The percentage of patients who develop anastomotic leakage | Within 30 days after operation | 
| Postoperative anal function assessed by Wexner scale | Ranging from 0 (perfect continence) to 20 (complete incontinence) | 2 years since the start of treatment | 
| Postoperative anal function assessed by Vaizey scale | Ranging from 0 (perfect continence) to 24 (complete incontinence) | 2 years since the start of treatment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of sphincter-preservation rates | The percentage of patients who preserve the anatomical structure of the anus | Within 30 days after operation | 
| The number of short-term postoperative complications | The number of grade II and higher postoperative complications according to the Clavien-Dindo classification | Within 30 days after operation | 
| Postoperative hospital stay | The time between the operation date and the discharge date. | Within 30 days after operation | 
| Hospitalization costs | The total cost of hospitalization | Within 30 days after operation | 
| 30-Day Readmission Rate | Percentage of readmitted patients within 30 days after operation | Within 30 days after operation | 
| Disease-free survival | Disease-free survival is defined as the time from surgery to recurrence of tumor or death | Up to 5 years after the last patient recruited | 
| Overall survival | Overall survival is defined as the time from surgery until death from any cause. | Up to 5 years after the last patient recruited |