Clinical experience of EET therapy for 75 advanced cancer patients.

Background: Exogenous/endogenous TNF (EET) therapy has a strong effect which causes inflammation in the body. Together with the antitumor effect of a single administration, the complementary effect of immunotherapy based on specific immunostimulation of tumor cells is also expected. We studied the characteristics of EET therapy in cases of advanced cancer. Patients and methods: The patients were 75 cases with advanced cancer including 48 cases of colon cancer, 10 cases of urological cancer, and 9 cases of gynecological cancer. One course of therapy was composed of the intravenous administration of either IFN-γ or TNF-S AM2 followed 3 hours later by OK-432. At least 2 courses were repeated during a 2 weeks period. Results: As response cases, partial response (PR) was observed in 7 of the 42 cases of colon cancer (17%) which had an evaluable lesion. Objective responses of lung metastases were found in the patients with multiple organ metastases of cervical cancer, ovarian cancer and uterine rhabdomyosarcoma. The group of colorectal cancer patients with liver metastases which underwent more than 5 courses of the therapy showed a longer survival period compared to the control group. One of the side effects, transitory hypotension, was observed in 46 % of the cases. Conclusion: In spite of restricted objective responses to date with EET therapy alone, anticancer effects observed in various kinds of tumors and activation of a cytokine network by which Th1 cells might be specifically activated suggest that a new biotherapy based on EET therapy may have potential.