Effect and safety of intraoperative intraperitoneal chemotherapy on patients suffering from colorectal cancer

Colorectal cancer (CRC), the third most commonly diagnosed malignant carcinoma and the third most common cause of carcinoma-related mortality, continues to be a major international health problem. And approximately 33% of patients suffer from recurrence after radical surgery. Free malignant cell implanting in the peritoneum is generally accepted as one of the main reasons of such outcome. We did this present clinical study with the aim of evaluating the effects and safety of intraoperative intraperitoneal chemotherapy (IOC) on patients suffering from colorectal cancer, with hoping to find a novel, effective, and available approach to deal with malignant cell implanting during surgeries.

In total, 391 patients who went through colorectal radical surgery were considered eligible between June 1, 2017, and December 31, 2018. 220 patients were treated with surgery without IOC, while other 171 patients received surgery plus IOC. Clinical characteristics, operative findings, postoperative short-term outcomes, disease-free survival (DFS), and overall survival (OS) were compared between these above 2 groups in the selected population.

The present research included 391 patients (251 men and 140 women) who underwent surgery without IOC (n = 171) or surgery plus IOC (n = 220), with a mean (SD) age of 60.4 (9.7) years in the surgery without IOC group and 60.6 (8.7) in the surgery plus IOC group (P=.85). No significant differences were witnessed between the two groups in surgery-related information and postoperative complications. It is worth noting that IOC independent of other factors was associated with a favor prognosis in CRC patients with stage II/III (HR 0.50, 95%CI 0.30-0.82, P=.006). Moreover, for patients with stage II colorectal carcinoma, DFS did not differ between two groups (P=.553, Kaplan-Meier log-rank), and OS was no exception. In stage III CRC patients, the estimated DFS rate for patients receiving IOC was 82.2% and patients without IOC was 66.4% after 3 years, which demonstrated that IOC was associated with a favorable prognosis in stage III patients (P=.012, Kaplan-Meier log-rank). Furthermore, the differences were still remained between the two groups when considering the influence about postoperative chemotherapy (P=.014, Kaplan-Meier log-rank). IOC can also significantly improve patients' overall survival whether they get treatment with POC (P=.006, Kaplan-Meier log-rank; P=.025, Kaplan-Meier log-rank).

In the present study, we have found that surgery plus IOC generated a favorable prognosis for stage III CRC patients but not stage II without any side-effects when the dosage of lobaplatin was 0.1g/L. As a new, safe, and simple procedure, IOC therapy is easily performed-and does not require any special devices or techniques. Thus, IOC is a promising and exciting therapeutic strategy for patients with CRC.