Flat Dose vs. Weight-based IP Chemotherapy for CRS/HIPEC

Peritoneal carcinomatosis from advanced gastro-intestinal malignancy has historically been associated with poor overall survival (≤ 12 months) with few treatment options. Cytoreductive surgery (CRS), which involves removal of all macroscopic tumor nodules, combined with direct administration of heated intra-peritoneal (IP) chemotherapy (HIPEC) to the affected peritoneal surfaces, has been shown to be an effective treatment option that extends overall survival among certain cases of peritoneal carcinomatosis. IP chemotherapy allows delivery of a high dose of cytostatic drug directly onto the peritoneal surfaces at risk for microscopic residual disease while systemic exposure remains limited. Additionally, hyperthermia is known to enhance the cytotoxicity of several agents (including Mitomycin C) and improves the depth of peritoneal penetration. This trial will be a randomized phase 2 comparison of flat dose versus weight-based dose Mitomycin C. The hypothesis of this study is that HIPEC weight-based dosing may result in similarly effective peritoneal Mitomycin C concentrations with less systemic absorption and potential systemic toxicity, compared with the HIPEC flat dosing approach in patients undergoing CRS/HIPEC.