Work

Surgical Impact on Postoperative Morbidity in Colorectal Cancer with Peritoneal Metastasis: A Multicenter Prospective Observational Study

Year: 2026

Type: article

Abstract: Aim: The objective of this study was to identify the factors influencing postoperative morbidity in patients with colorectal cancer (CRC) and synchronous peritoneal metastasis (PM). Methods: This multicenter prospective observational study was conducted by the Japanese Society for Cancer of the Colon and Rectum. Patients with CRC and synchronous PM were recruited from 28 institutions in Japan between October 2012 and December 2016. Postoperative morbidity was the primary endpoint of the analysis, and diverse variables were included for evaluation via logistic regression analysis. Results: A total of 137 patients, including 78 men and 59 women, were enrolled in this study. The median age was 67 years. Among patients with synchronous PM, 55 had PM alone, classified as M1c1, whereas 82 had PM with metastases to other organs, classified as M1c2. In multivariate analysis, M1c2 status and operation time >170 minutes were significantly associated with postoperative morbidity (odds ratio [OR] = 3.89, 95% confidence interval [CI] 1.31-11.51, p = 0.01; and OR = 4.56, 95% CI 1.32-11.51, p = 0.01, respectively). In the overall cohort, postoperative morbidity was not significantly associated with overall survival. Conclusion: This study demonstrated that M1c2 is an independent risk factor for postoperative morbidity. When planning surgery for peritoneal metastasis, particularly in patients with distant organ metastases, the elevated risk of postoperative morbidity should be carefully considered in surgical decision-making.

Source: Journal of the Anus Rectum and Colon

DOI: 10.23922/jarc.2026-011