A multi-institutional prospective study of lentinan in advanced gastric cancer patients with unresectable and recurrent diseases: effect on prolongation of survival and improvement of quality of life. Kanagawa Lentinan Research Group.

Lentinan is one of the host-mediated anti-cancer drugs which has been shown to affect host defense immune systems. Although the mechanisms involved in the antitumor effects of lentinan have been reported experimentally, the clinical outcome on prolongation of survival and improvement of quality of life in gastric cancer patients with unresectable or recurrent diseases has yet to be clarified. The aim of the present study was to investigate whether administration of lentinan prolonged survival or improved quality of life in these patients.A multi-institutional randomized prospective protocol, consisting of patients administered tegafur and cisplatin (control group), and patients administered lentinan, tegafur and cisplatin (lentinan group), was performed. Quality of life was investigated using a questionnaire survey.Median survival was significantly longer in the lentinan group than in the control group (297 days vs. 199 days, p = 0.028). One-year survival rate was greater in the lentinan group than in the control group (49.1% vs. 0%). Total QOL score, especially appetite and sleep quality, was significantly improved with the administration of lentinan.Lentinan is considered to prolong survival and improved quality of life when gastric cancer patients with unresectable or recurrent diseases are treated in combination with other chemotherapeutic agents.