Effect of mutation on the prognosis for patients with colorectal cancer undergoing cytoreductive surgery for synchronous peritoneal metastasis.

BACKGROUND

mutations (mutmut) are unfavorable prognostic factors for colorectal cancer (CRC) metastases to the liver and lungs. However, their effects on the prognosis for patients with synchronous peritoneal metastasis (S-PM) of CRC after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are controversial. In the study, we aimed to determine the effects of mutmut on the prognosis for patients with S-PM who received CRS.

METHODS

A total of 142 patients diagnosed with S-PM between July 2007 and July 2019 were included in this study. The demographics, mutmut status, overall survival (OS), and progression-free survival (PFS) of the patients were evaluated. The Kaplan-Meier method and log-rank test were used to estimate the difference in survival between groups.

RESULTS

Among 142 patients, 68 (47.9%) showed mut and 42 (29.5%) showed mut. The median OS values were 8.4 and 34.3 months for patients with mut and wild-type, respectively (<0.01). However, status was not significantly associated with median OS (=0.76). Multivariate analysis revealed carcinoembryonic antigen, CRS, HIPEC, and mut as independent predictors for OS. Based on these findings, a nomogram was constructed. The C-index was 0.789 (95% confidence interval, 0.742-0.836), indicating good predictive ability of the model. Furthermore, the 1- and 2-year survival calibration plots showed good agreement between the predicted and actual OS rates. The area under curves of the 1- and 2-year survival predictions based on the nomogram were 0.807 and 0.682, respectively. Additionally, mut was significantly associated with lower PFS (<0.001).

CONCLUSIONS

mut is an independent prognostic risk factor for S-PM. The established nomogram predicted the OS of patients with CRC having S-PM with high accuracy, indicating its usefulness as a valuable prognostic tool for the designated patient cohort.