The effectiveness of cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) have been addressed for the treatment of peritoneal carcinomatosis in selected patients. However, prophylactic HIPEC in colorectal cancer patients at high risk of metachronous peritoneal metastases remained controversial. In this study, patients with colorectal cancer cT4N0-2M0(AJCC/UICC staging system 8th edition) and planed to undergo intentionally colectomy (laparotomy, laparoscopyor robotic ) are randomized into HIPEC group and control group. In HIPEC group, closed HIPEC is performed with Mitomycin C(30mg/m2) at 43 C for 90 minutes, simultaneously or within 2 days after colectomy and followed by systemic chemotherapy. For the patients in the control group, systemic chemotherapy were administered after colectomy. The primary endpoint is peritoneal recurrence-free survival (pRFS) rate. Secondary end points include overall survival (OS) rate, disease free survival (DFS) rate, liver metastatic rate, toxic effects, quality of life scores. All efficacy analyses are conducted in the intention-to-treat population, per-protocol population and pT4 subgroups due to pathologic tumor invasion can not be acquired before HIPEC. Safety analysis include only patients who receive their randomly assigned treatment.

