[Clinical study of using basement membrane biological products in pelvic floor reconstruction during pelvic...

Objective: To investigate the value of reconstruction of pelvic floor with biological products to prevent and treat empty pelvic syndrome after pelvic exenteration (PE) for locally advanced or recurrent rectal cancer. Methods: This was a descriptive study of data of 56 patients with locally advanced or locally recurrent rectal cancer without or with limited extra-pelvic metastases who had undergone PE and pelvic floor reconstruction using basement membrane biologic products to separate the abdominal and pelvic cavities in the Department of Anorectal Surgery of the Second Affiliated Hospital of Naval Military Medical University from November 2021 to May 2022. The extent of surgery was divided into two categories: mainly inside the pelvis (41 patients) and including pelvic wall resection (15 patients). In all procedures, basement membrane biologic products were used to reconstruct the pelvic floor and separate the abdominal and pelvic cavities. The procedures included a transperitoneal approach, in which biologic products were used to cover the retroperitoneal defect and the pelvic entrance from the Treitz ligament to the sacral promontory and sutured to the lateral peritoneum, the peritoneal margin of the retained organs in the anterior pelvis, or the pubic arch and pubic symphysis; and a sacrococcygeal approach in which biologic products were used to reconstruct the defect in the pelvic muscle-sacral plane. Variables assessed included patients' baseline information (including sex, age, history of preoperative radiotherapy, recurrence or primary, and extra-pelvic metastases), surgery-related variables (including extent of organ resection, operative time, intraoperative bleeding, and tissue restoration), post-operative recovery (time to recovery of bowel function and time to recovery from empty pelvic syndrome), complications, and findings on follow-up. Postoperative complications were graded using the Clavien-Dindo classification. Results: The median age of the 41 patients whose surgery was mainly inside the pelvis was 57 (31-82) years. The patients comprised 25 men and 16 women. Of these 41 patients, 23 had locally advanced disease and 18 had locally recurrent disease; 32 had a history of chemotherapy/immunotherapy/targeted therapy and 24 of radiation therapy. Among these patients, the median operative time, median intraoperative bleeding, median time to recovery of bowel function, and median time to resolution of empty pelvic syndrome were 440 (240-1020) minutes, 650 (200-4000) ml, 3 (1-9) days, and 14 (5-105) days, respectively. As for postoperative complications, 37 patients had Clavien-Dindo < grade III and four had ≥ grade III complications. One patient died of multiple organ failure 7 days after surgery, two underwent second surgeries because of massive bleeding from their pelvic floor wounds, and one was successfully resuscitated from respiratory failure. In contrast, the median age of the 15 patients whose procedure included combined pelvic and pelvic wall resection was 61 (43-76) years, they comprised eight men and seven women, four had locally advanced disease and 11 had locally recurrent disease. All had a history of chemotherapy/ immunotherapy and 13 had a history of radiation therapy. The median operative time, median intraoperative bleeding, median time to recovery of bowel function, and median time to relief of empty pelvic syndrome were 600 (360-960) minutes, 1600 (400-4000) ml, 3 (2-7) days, and 68 (7-120) days, respectively, in this subgroup of patients. Twelve of these patients had Clavien-Dindo < grade III and three had ≥ grade III postoperative complications. Follow-up was until 31 October 2022 or death; the median follow-up time was 9 (5-12) months. One patient in this group died 3 months after surgery because of rapid tumor progression. The remaining 54 patients have survived to date and no local recurrences have been detected at the surgical site. Conclusion: The use of basement membrane biologic products for pelvic floor reconstruction and separation of the abdominal and pelvic cavities during PE for locally advanced or recurrent rectal cancer is safe, effective, and feasible. It improves the perioperative safety of PE and warrants more implementation.