Immunotherapy of gastrointestinal cancer patients with levamisole

Levamisole was administered to 177 patients with gastrointestinal cancer (88 curative resection, 58 noncurative resection and 31 without resection). It was administered at a daily dose of 150 mg for three consecutive days every other week. The administration was started, as a rule, 3 days before operation. This medication was repeated as frequently as possible at least for one month. The cellular immunity and 18-month survival rate of treated and control groups were compared. Levamisole effectively improved peripheral lymphocyte blastformation against phytohemagglutinin and increased the numbers of peripheral blood lymphocytes. Levamisole caused extremely high blastformation rates, in general, enhanced PPD reactions in non-curative resection cases 7 months after operation and showed no influence upon the number of peripheral blood lymphocyte. The effect of levamisole on the 6-month survival rate was most marked in patients without resection. Increased 12-month survival rate was marked in non-curative resection cases and, to a lesser extent, curative resection cases. Patients without resection had a slightly improved 12-month survival rate. Levamisole improved the 18-month survival rate in resectable cases; however, there were no significant differences in 18-month survival between levamisole and control groups of patients not undergoing resection. The results suggest that levamisole is effective in the patients whose tumor cells have been decreased by any method.