Repeat Cytoreductive Surgery for Colorectal Cancer Metastatic to the Peritoneal Cavity

Area of Science:

• Surgical Oncology
• Gastroenterology
• Cancer Research

Background:

• Colorectal cancer (CRC) is a significant global health concern, with peritoneal metastases (PM) indicating a poor prognosis.
• While cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival for initial CRC-PM, the efficacy of repeat CRS for recurrent PM is less understood.

Purpose of the Study:

• To evaluate the outcomes of repeat cytoreductive surgery (CRS) in patients with recurrent colorectal cancer peritoneal metastases (PM).
• To determine the predictive value of initial CRS outcomes on subsequent recurrence-free survival (RFS) and peritoneal disease-free survival (PDFS) after repeat CRS.

Main Methods:

• Retrospective analysis of 139 colorectal cancer patients who underwent one or more CRS procedures between 2008 and 2023.
• Evaluation of recurrence-free survival (RFS), peritoneal disease-free survival (PDFS), and overall survival (OS) using Kaplan-Meier analysis.
• Comparison of outcomes between single and multiple CRS procedures, and between 'complete' versus 'targeted' index CRS.

Main Results:

• 81% of patients experienced recurrence after the first CRS (CRS1), with most having peritoneal recurrence.
• Recurrence-free survival (RFS) and peritoneal disease-free survival (PDFS) were similar after CRS1 and CRS2 (p=0.17 and p=0.34).
• Patients undergoing 'targeted' index CRS had shortened PDFS (p<0.01) but similar overall survival (OS) compared to 'complete' CRS.

Conclusions:

• Outcomes after the first CRS (CRS1) largely predict outcomes after the second CRS (CRS2).
• A subset of patients can achieve long-term RFS/PDFS after repeat CRS.
• Re-do CRS should be considered for carefully selected patients with recurrent colorectal cancer peritoneal metastases.