Resection of the Inferior Vena Cava Due to Tumor Involvement
Condition: Neoplasms; Surgery--Complications; Vascular Diseases; Vein Disease
MeSH terms: Neoplasms; Vascular Diseases
Study type: Observational

Summary: 
      The involvement of the inferior vena cava (IVC) in advanced abdominal tumors is a surgical
      challenge, given the high postoperative morbidity and poor long-term prognosis. The goal was
      to analyze the experience, perioperative management, and results.

      Investigators have evaluated short and long-term results of surgical resections of tumors
      with associated inferior vena cava resection performed between 2012 and 2018.
    

Detailed description: 
      Data Collection:

      Investigators retrospectively looked at patients who, from January 2012 to December 2018,
      underwent surgical procedures in the unit for IVC-specific tumors or for IVC resections due
      to secondary infiltrative tumors. In some cases, the IVC involvement was an intraoperative
      finding.

      Patients with primary or secondary IVC involvement who underwent surgery were included in the
      study. Patients with metastasis found during intraoperative exploration were excluded from
      the study.

      Diagnostic management included establishment of a medical history, performance of clinical
      examination and imaging tests, including an abdominal ultrasound and computerized tomography
      (CT) scan, to confirm the tumor origin and growth, as well as infiltration, if any, of
      adjacent structures. These also allowed to rule out distant metastases, and to assess
      resectability and the option for vascular reconstruction. In some cases, the decision to
      resect the IVC was made during surgery, because IVC involvement was an intraoperative finding
      which remained unknown up to that point.

      The variables taken into account were age, sex, BMI, the American Society of
      Anesthesiologists (ASA) classification, tumor type, preoperative chemotherapy and/or
      radiation therapy. In addition, another variable considered was whether the finding was
      intraoperative or preoperative. Perioperative clinical results, surgical approach, type of
      IVC resection and reconstruction, and intraoperative complications were recorded. Details of
      the postoperative course were collected. Some of the key short-term data recorded included
      length of hospital stay, complications' ranking (according to the Clavien-Dindo score;
      'severe complication' is defined as greater or equal to IIIa), re-operation, re-admission and
      operative mortality (< 90 days after operation). Some of the key long-term data recorded were
      patency of IVC or prosthesis (as determined by a CT scan), neoadjuvant and adjuvant
      chemotherapy, specific disease-free survival and overall survival (OS).

      Surgical Approach Management of IVC involvement was categorized in three groups, according to
      the surgical repair necessary: resection with primary repair, resection with autologous or
      prosthetic patch repair, and circumferential resection with graft replacement. Primary repair
      was defined as resection of a portion of the IVC with primary closure when <50% narrowing of
      the lumen would result. Patch closure was planned when a larger defect created by the
      resection required patch repair to avoid narrowing of the IVC. Circumferential resection of
      the IVC was managed with replacement using a prosthetic graft.

      For surgical planning, investigators used the classification according to Kulayat, which
      subdivides the IVC into three segments: upper portion (level 1)-extending from the opening of
      the hepatic veins up to the right atrium-, middle portion (level 2)-extending from the renal
      veins to the hepatic veins-, and lower portion (level 3)-extending from the junction of the
      iliac veins to the opening of the renal veins.

      Intravenous heparin was not used during the clamping time of the IVC. Heparinized saline
      (2units/ml of heparin sodium) was used, however, to flush out the prosthesis if being used
      for reconstruction. A therapeutic heparin dose is used for 30 days after surgery, and
      patients with prosthesis receive oral blood thinners for at least six months.

      Follow-up Patient follow-up included measuring tumor markers and performing a chest-abdominal
      CT scan every three months for the first two years; then, twice a year; and then, annually,
      after five years. Local recurrence was defined as a return of a tumor within the surgical
      field, whereas systemic recurrence was defined as recurrent disease outside said field.
    

Intervention name(s): Resection of inferior vena cava and reconstruction
Intervention type(s): Procedure
Intervention description(s): Resection of inferior vena cava and reconstruction with primary repair, resection with autologous or prosthetic patch repair, and circumferential resection with graft replacement
Observational model: Case-Only
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        Patients who, from January 2012 to December 2018, underwent surgical procedures in our unit
        for IVC-specific tumors or for IVC resections due to secondary infiltrative tumors.
      
Keywords: Inferior vena cava; radical resection; Vascular reconstruction