Irradiation, bleomycin and hyperbaric oxygen in the treatment of oral carcinoma

The present report is the sixth in a series of combination therapy trials in oral carcinoma in South India conducted since 1960. In the fifth trial a combination of bleomycin (BLM) and irradiation was compared with irradiation alone. The results gained and the subsequent experience in an unselected series demonstrated in buccal mucosal squamous cell carcinomas a highly superior effect with the irradiation-BLM combination, but still revealed a failure rate around 30 per cent. The present clinical trial--irradiation + BLM was compared with irradiation + BLM + hyperbaric oxygen (HbO) and irradiation + placebo + HbO--was undertaken in an attempt to eliminate or at least reduce these failures. The results were unexpectedly disappointing in that the irradiation combined with BLM + HbO proved to be inferior to irradiation + BLM. An attempt has been made to elucidate the possible reasons for this surprising outcome.