Peritoneal carcinomatosis in patients with digestive cancer carries a poor prognosis, with a majority of patients dying within 6 months. Mitomycin C has been reported to have some antitumor efficacy in this setting. We performed combination intraperitoneal hyperthermia and mitomycin to potentiate the effect of mitomycin C in 83 patients with peritoneal involvement due to digestive cancers. Eighty six IPCH procedures were performed using inflow temperature 46 to 49 degrees Celsius, using a closed circuit, during 90 minutes. Mitomycin C was administered as a perfusate at 10 mg/l. Primary tumors were essentially gastric (42) and colorectal (27). Mortality and morbidity rates were 3/83 and 5/83 respectively. For resectable tumors, the median survival time was 16 months in stage 1 and 2 carcinomatosis (malignant granulations less than 5 mm in diameter). For resectable gastric cancers with stage 1 and 2 carcinomatosis, one, two and three year actuarial survival rates were 80, 61 and 41% respectively. In conclusion, IPCH appears to be an interesting therapeutic option in patients with digestive cancers and small malignant peritoneal granulations (stage 1 and 2).