[Clinical significance of immunotherapy for lung cancer--present and future]

To evaluate the clinical efficacy of OK-432 immunotherapy as an surgical adjuvant for lung cancer patients, three kinds of randomized controlled trials were done. In the first trial, patients were randomized into two groups: an immunochemotherapy (IM-C) group and a chemotherapy (control) group. For IM-C group, OK-432 (2KE/w) was injected intramuscularly for three years. Significant improvement of the survival rates in the IM-C group was noted in the following items: all resected cases, stages I+II cases, stage III cases, completely resected cases, incompletely resected cases and cases with epidermoid carcinoma. However, in comparison to adenocarcinoma there was no significant difference between the two groups. In the second trial, patients were randomized into an intramuscular injection group and an intradermal injection group. In comparisons to the survival rates, there were no significant differences between the two groups. In the third trial, stage I patients were randomized into a group treated with intradermal injection (5KE/w) and no adjuvant group. To date, there was no significant difference between the two groups. It is concluded that OK-432 immunotherapy, with concomitant use of chemotherapy, have favourable effect on the patient with squamous cell carcinoma. No definitive difference of clinical effects between intramuscular injection and intradermal injection.