The benefit of intraperitoneal chemotherapy for the treatment of colorectal carcinomatosis

The clinical practice of hyperthermic intraperitoneal chemoperfusion (HIPEC) for carcinomatosis has lacked preclinical justification. A standardized mouse model was created to evaluate the independent effects of intraperitoneal chemotherapy. Diffuse colorectal carcinomatosis was generated in mice prior to intraperitoneal lavage with mitomycin C (MMC) at clinically comparable dosing for variable lengths of time. Tumor volumes, MMC tissue concentrations and survival were measured in comparison to saline lavage and intravenous MMC. Magnetic resonance imaging revealed a direct correlation between tumor volume, MMC dose and exposure time and survival. Intravenous MMC demonstrated a rapid clearance from the blood, lower peritoneal tissue concentrations, less tumor growth inhibition and decreased survival compared to intraperitoneal administration. Intraperitoneal chemotherapy inhibited tumor growth independent of cytoreduction or hyperthermia, demonstrated improved peritoneal tissue concentration and was associated with increased survival. These data support the clinical utility of the intraperitoneal chemotherapy component of HIPEC.