Colorectal Cancer with Peritoneal Metastases: The Impact of the Results of PROPHYLOCHIP, COLOPEC, and PRODIGE 7 Trials on Peritoneal Disease Management

SIMPLE SUMMARY: Colorectal peritoneal metastases could potentially benefit from locoregional treatments such as cytoreduction combined with hyperthermic intraperitoneal chemotherapy (HIPEC). Three recently published RCTs that have investigated HIPEC in the setting of radical or prophylactic/II^ look surgery have improved the current knowledge of the treatment of CRC PM. The current review summarizes the results of these trials, emphasizing the highlights and criticisms and focusing on the potential impact and future directions in the clinical practice of HIPEC. Oxaliplatin-based HIPEC seems ineffective in improving surgery results in patients with CRC PM. Moreover, the same oxaliplatin-based regimen is ineffective in preventing CRC PM occurrence and should be abandoned. Several ongoing trials are investigating mitomycin-based HIPEC after radical surgery or as a prevention strategy. Meanwhile, HIPEC should still be considered a therapeutic option for selected patients and offered by dedicated, experienced centers and surgical teams. ABSTRACT: HIPEC is a potentially useful locoregional treatment combined with cytoreduction in patients with peritoneal colorectal metastases. Despite being widely used in several cancer centers around the world, its role had never been investigated before the results of three important RCTs appeared on this topic. The PRODIGE 7 trial clarified the role of oxaliplatin-based HIPEC in patients treated with radical surgery. Conversely, the PROPHYLOCHIP and the COLOPEC were designed to chair the role of HIPEC in patients at high risk of developing peritoneal metastases. Although all three trials demonstrated the relative ineffectiveness of HIPEC for treating or preventing peritoneal metastases, these results are not sufficient to abandon this technique. In addition to some criticisms relating to the design of the trials and their statistical value, the oxaliplatin-based HIPEC was found to be ineffective in preventing or treating peritoneal colorectal metastases, especially in patients already treated with systemic platinum-based chemotherapy. Several studies are ongoing investigating further HIPEC drugs and regimens. The review deeply discussed all the aspects and relapses of this new evidence.