A systematic review and meta-analysis of the randomized controlled trials on adjuvant intraperitoneal chemotherapy for resectable gastric cancer

Background: The purpose of this systematic review and meta-analysis was to determine the effectiveness and safety of adjuvant intraperitoneal chemotherapy for patients with locally advanced resectable gastric cancer. Methods: Studies eligible for this systematic review included those in which patients with gastric cancer were randomly assigned to receive surgery combined with intraperitoneal chemotherapy versus surgery without intraperitoneal chemotherapy. There were no language restrictions. After independent quality assessment and data extraction, data were pooled for meta-analysis. Results: Thirteen reports of randomized controlled trials (RCTs) were included for quality appraisal and data extraction. Ten reports were judged to be of fair quality and subjected to meta-analysis. A significant improvement in survival was associated with hyperthermic intraoperative intraperitoneal chemotherapy (HIIC) alone (hazard ratio [HR] = 0.60; 95% CI = 0.43 to 0.83; p = 0.002) or HIIC combined with early postoperative intraperitoneal chemotherapy (EPIC) (HR = 0.45; 95% CI = 0.29 to 0.68; p = 0.0002). There was a trend towards survival improvement with normothermic intraoperative intraperitoneal chemotherapy (p = 0.06), but this was not significant with either EPIC alone or delayed postoperative intraperitoneal chemotherapy. Intraperitoneal chemotherapy was also found to be associated with higher risks of intra-abdominal abscess (RR = 2.37; 95% CI = 1.32 to 4.26; p = 0.003) and neutropenia (RR = 4.33; 95% CI = 1.49 to 12.61; p = 0.007). Conclusions: The present meta-analysis indicates that HIIC with or without EPIC after resection of advanced gastric primary cancer is associated with improved overall survival. However, increased risk of intra-abdominal abscess and neutropenia are also demonstrated.