The absence of benefit of perioperative chemotherapy in initially resectable peritoneal metastases of colorectal cancer origin treated with complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: A retrospective analysis.

INTRODUCTION

The aim of this study was to compare the outcome of patients with peritoneal metastasis (PM) of colorectal origin treated with complete cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) with or without perioperative systemic chemotherapy (PCT+/PCT-).

PATIENTS AND

METHODS

Retrospective analysis of 125 patients treated with complete CRS (R0/R1) and HIPEC for PM from colorectal origin in two Belgian academic centers between 2008 and 2017. Disease-free survival (DFS) and overall survival (OS) were assessed with regard to PCT. Statistical analyses were adjusted for non-balanced survival risk factors.

RESULTS

The PCT+ group (n = 67) received at least 5 cycles of PCT and the PCT-group (n = 56) did not receive PCT. The groups were well balanced for all prognostic factors except presentation of synchronous disease (more in PCT+). Survival analysis was adjusted to peritoneal cancer index and presentation of synchronous disease. After a median follow-up of 54±5-months, the 1, 3, 5-years OS in the PCT+ group were 98%, 59% and 35% compared to 97%, 77% and 56% in the PCT-group (HR = 1.46; 95% CI:0.87-2.47; p = 0.155). The 1,3 and 5 years DFS in the PCT+ group were 47%, 13% and 6% compared to 58%, 29% and 26% respectively in the PCT- (HR = 1.22; 95% CI:0.78-1.92; p = 0.376).

CONCLUSION

This study does not show any clear benefit of PCT in carefully selected patients undergoing R0/R1 CRS and HIPEC for colorectal PM. The ongoing CAIRO6 trial randomizing CRS/HIPEC versus CRS/HIPEC and PCT will probably clarify the role of PCT in patients with resectable PM.