[Ecological study of the pharyngeal bacterial flora in patients with lung cancer]

We investigated the relationship between changes in pharyngeal bacterial flora and the immunological condition of 10 lung cancer patients before and after anti-cancer chemotherapy. There were significant differences in bacterial flora between normal subjects and patients. However, there were little differences in pharyngeal flora in patients before and after chemotherapy. In 4 out of the 10 lung cancer patients, the ratio of anaerobic bacteria/total bacteria of pharyngeal flora decreased. These 4 cases were in the non-responsive (NC, PD) group of anti-cancer chemotherapy. After administration of anti-cancer drugs, the ratio of anaerobic bacteria increased. No aerobic gram negative rods were isolated at any time during the observation period, because immunological suppression was mild. The results indicate the importance of surveillance for the immunological state of the hosts and changes in pharyngeal bacterial flora.