[Rationality of performing hyperthermic intraperitoneal chemotherapy 5-8 weeks after primary tumor resection for patients with locally advanced colorectal cancer-based on COLOPEC].

Hyperthermic intraperitoneal chemotherapy (HIPEC) has a unique effect on the prevention and treatment of peritoneal metastasis from malignancies. Recently, the first prospective, multicenter, randomized controlled clinical trial of HIPEC to prevent the development of peritoneal metastasis after curative surgery for patients with locally advanced colon cancer was published in the " Lancet Gastroenterol Hepatol " (COLOPEC). Regrettably, no significant difference was observed in 18-month peritoneal metastasis-free survival between postoperative adjuvant HIPEC and standard systemic chemotherapy for patients with T4 stage or perforated colon cancer. However, we wonder whether we might achieve better outcomes by further optimizing the following issues: (1) We propose that the inclusion criteria for that trial may not be entirely reasonable, which included pT4N0-2M0 and perforation. Additionally, we found that 91% of patients underwent HIPEC 5-8 weeks after primary tumor resection. (2) The imbalance in starting time of postoperative systemic chemotherapy between the two groups may have a negative impact.(3) Nine patients with peritoneal metastasis preceding HIPEC might weaken the potential efficacy of HIPEC. (4) We wonder whether HIPEC using high-dese oxaliplatin (460 mg/m(2)) perfusing 30 minutes for one cycle is the optimal regimen. Therefore, we are planning to conduct a randomized controlled trial (HIPEC-06) in accordcance with the characteristics of Chinese patients, to explore the clinical efficacy of curative surgery combined with HIPEC in the treatment of cT4 colorectal cancer.