Binyi Xiao

Efficacy and safety of subtotal pelvic peritonectomy for colorectal cancer patients with peritoneal metastasis confined to the pelvic cavity

Cytoreductive surgery has shown survival benefits for colorectal cancer (CRC) patients with peritoneal metastasis. However, the optimal extent of peritonectomy remains controversial in cases of limited peritoneal metastases. This study modified selective pelvic peritonectomy (SPP) into subtotal pelvic peritonectomy (STPP) for metastasis confined to pelvic cavity, and aimed to evaluate its feasibility, safety, and impact on survival outcomes. CRC patients with limited peritoneal metastasis confined to the pelvic cavity who underwent CC0 (no macroscopic residual cancer remained) resection were included from a prospectively collected database. Surgical complications, disease-free survival (DFS), and overall survival (OS) were analyzed. A total of 67 patients were included (26 in the STPP group and 41 in the SPP group). Clinically, STPP was found to be feasible and without increased surgical complications or mortality rates. At a median follow-up of 33.9 months, the 3-year DFS was 65.9 % and 30.7 % in STPP and SPP groups, respectively (P= 0.002). The 3-year OS was 84.1 % and 68.5 % in STPP and SPP groups, respectively (P= 0.006). Moreover, STTP was independently associated with improved DFS (HR = 0.351, 95 % CI 0.165-0.745, P= 0.006) and OS (HR = 0.324, 95 % CI 0.116-0.902, P=0.032). Female gender was also independently associated with poor DFS (HR = 2.146, 95 % CI 1.078-4.271, P= 0.031). Among 24 female patients with remaining ovaries, 9 (37.5 %) cases developed metachronous ovarian metastasis, and of these 6 underwent a second operation. Subtotal pelvic peritonectomy is associated with promising long-term outcomes in CRC patients with peritoneal metastasis confined to the pelvic cavity. Prophylactic bilateral oophorectomy should be strongly considered during cytoreductive surgery.