[Studies on usefulness of postoperative adjuvant chemotherapy with lentinan in patients with gastrointestinal cancer].

The usefulness of Lentinan, as an agent for postoperative adjuvant therapy, was investigated in patients with gastrointestinal cancer. Sixty-one patients were classified into three stages by a degree of advance for cancer (Stage II, III, IV). Furthermore, each group was put into the control group (C group) and the Lentinan group (L group), received 600 mg/day of Tegafur p. o. only or 600 mg/day of Tegafur p. o. and 2 mg/week of Lentinan i. v., respectively. Then total lymphocyte counts and NK cell activities were measured and analysis of lymphocyte subsets by two color flow cytometry was carried out every two months. The results were as follows: 1) Some parameters were preserved in higher levels in the L group especially in the stage IV. 2) In the stage IV, total lymphocyte counts of the L group were preserved higher levels compared to those of the C group. The same tendency was observed in OKT3, OKT4 and OKT8 positive cell counts. 3) In the stage IV, both OKT8+ x Leu15+ cell (suppressor T cell) and OKT8+ x Leu15- cell (killer T cell) counts tended to decrease in the C group. 4) In the stage IV, the NK cell activities of the L group were preserved in higher level compared to those of the C group. Leu7+ x Leu11-, Leu7+ x Leu11+ and Leu11- x Leu11+ cells counts tended to preserve in the L group. From these results, it was suggested that Lentinan had a marked immunopotentiating efficacy in the stage IV among gastrointestinal cancer patients.