[Change of blood lentinan level in patients with advanced cancers]

A conventional limulus test can detect not only endotoxin but also beta(1----3) glucan. Therefore, with a quantitative limulus test, the limulus colorimetric test, we studied the pharmacokinetics of lentinan, an antitumor beta(1----3) glucan preparation, in the blood of 10 healthy volunteers and 20 patients with advanced cancers. The calibration curve of lentinan in the human plasma was linear in the range of 0 to 100 ng/ml. Two mg of lentinan was administered once a week and blood samplings for the measurement were done immediately before the next lentinan administration to document trough-levels serially at a week interval. Trough-levels tended to rise gradually and showed a rapid elevation between 4 and 8 weeks after beginning of administration. This phenomenon may correlate closely with the antitumor effect of lentinan and, therefore, deserves further investigations.