EFFECTS OF INTRAOPERATIVE CHEMOHYPERTHERMIA IN PATIENTS WITH GASTRIC-CANCER WITH PERITONEAL DISSEMINATION

Background. The most common cause of noncurative resection and recurre nce in gastric cancer is peritoneal seeding. However, the results of t reatment of peritoneal dissemination with chemotherapy have been. poor with 5-year survival rates of 0%. Methods. A new in vitro thermochemo sensitivity test was performed on gastric cancer cells obtained from 1 9 surgically resected specimens by using tetrazolium-based colorimetri c assay (MTT assay). A novel treatment of the intraoperative chemohype rthermia was undertaken in. 83 patients with gastric cancer with perit oneal dissemination. After aggressive resection of primary tumor, lymp h nodes, and peritoneal metastases, warned saline solution containing mitomycin. C 30 mg, etoposide 150 mg, and cisplatin 300 mg was introdu ced into the peritoneal cavity via a closed circuit continuous hyperth ermic peritoneal perfusion (CHPP) for 60 minutes to keep the abdominal temperature at 42 degrees to 43 degrees C by means of a heat exchange mechanism. Results. The in vitro thermochemosensitivity test showed t hat 43 degrees C enhanced the cytotoxic effects on. gastric cancer cel ls under clinically achievable drug concentrations. During CHPP, drug concentrations of cisplatin, mitomycin C, and etoposide in the perfusa te remained statistically higher than in the peripheral venous circula tion. Among 43 evaluable patients with residual peritoneal seeding, ei ght (19%) and nine (21%) exhibited complete response and partial respo nse, respectively. The overall 1-and 5-year survival rates were 43% an d 11%, respectively. Patients who underwent complete resection survive d significantly longer than those with residual disease, and those wit h complete response had a significantly better prognosis than did thos e with partial response or nonresponders. One-year survival rates of p atients with complete response, partial response, and nonresponders we re 88%, 27%, and 22%, respectively. Five patients survived longer than 5 years. Conclusions. Our triple treatment combining surgery and CHPP is an effective therapy for selected patients with gastric cancer wit h peritoneal dissemination.