Repeat Cytoreductive Surgery for Colorectal Cancer Metastatic to the Peritoneal Cavity

Colorectal cancer (CRC) is a leading cause of cancer-related death worldwide. 5-15% of CRC patients develop peritoneal metastases (PM), and those with PM have poor prognosis. For patients with new CRC-related PM, surgical treatment, including cytoreductive surgery (CRS) with/without hyperthermic intraperitoneal chemotherapy (HIPEC) has been shown to improve survival compared with systemic therapy alone; however, little is known about the benefits of re-do CRS for recurrent PM.

All CRC patients who underwent CRS with/without HIPEC (2008-2023) were retrospectively identified at one major referral center. Clinicodemographic variables were extracted by chart review. Recurrence-free survival (RFS), peritoneal disease-free survival (PDFS), and overall survival (OS) were evaluated using the Kaplan-Meier method.

Overall, 139 patients underwent one or more CRS procedures and were included in this study, with 56 patients undergoing two CRS procedures and 15 undergoing three or more CRS procedures. Median age was 50 years. 113 (81%) patients experienced recurrence after their first CRS (CRS1) compared with 45 (80%) after the second CRS (CRS2) and 13 (87%) after the third CRS (CRS3), with most patients experiencing peritoneal recurrence (73% after CRS1, 75% after CRS2, 67% after CRS3). RFS and PDFS were similar after CRS1 and CRS2 (p = 0.17 and p = 0.34, respectively). Patients who underwent a 'targeted' rather than 'complete' index CRS experienced shortened PDFS (p < 0.01) but equivalent OS (p = 0.84).

RFS/PDFS following CRS1 is largely predictive of RFS/PDFS after CRS2, with a small number of patients experiencing long-term RFS/PDFS after CRS2. Re-do CRS should be considered for appropriately selected patients with CRC-related PM.