Clinical effects of chemoimmunotherapy for patients with peritoneal carcinomatosis

The present study was undertaken to determine whether chemoimmunotherapy using activated killer cells is better than chemotherapy alone for cancer patients with peritoneal carcinomatosis. Thirty-one cancer patients received adoptive immunotherapy by activated killer cells and chemotherapy by anticancer drugs selected by a chemosensitivity test (chemoimmunotherapy group), and another 31 cancer patients received chemotherapy (chemotherapy group). The regimen of chemotherapy was determined by the results of a chemosensitivity test in both groups. The clinical effects including response rate and survival were assessed. Five patients (16.1%) achieved complete response (CR), and 17 patients (54.8%) partial response (PR) in the chemoimmunotherapy group (response rate: 22/31 patients = 71.0%), whereas 4 patients (12.9%) achieved CR, and 5 patients (16.1%) PR in the chemotherapy group (response rate: 9/31 patients = 29.0%). The response rate was higher in chemoimmunotherapy group than in chemotherapy group (p<0.05). However, no difference was observed in survival between the two groups. Therefore, it is necessary to develop methods to induce more potent killer cells for adoptive immunotherapy.