Usefulness of TS-1 and lentinan combination immunochemotherapy in advanced or recurrent gastric cancer--pilot study aiming at a randomized trial

The quality of life (QOL) of patients with advanced or recurrent gastric cancer is poor and their immunocompetence is low, making it important to conduct chemotherapy while at the same time improving their QOL and maintaining their immunocompetence. To improve QOL and increase compliance by reducing the side effects but not the antitumor effect of TS-1, a 2-week regime with 2-week administration of TS-1, and a 1-week drug-free interval in combination with the immunotherapeutic agent lentinan (LNT) was started in 5 patients with advanced or recurrent gastric cancer. Toxicity, efficacy, QOL, and immunological parameters were investigated preliminarily to examine whether or not usefulness of lentinan could be evaluated. QOL scores for appetite, nausea/vomiting, and abdominal pain/diarrhea showed improvement, although not in statistically significant values. The Th2 (CD4-positive, IL4-positive T cells) response in peripheral blood decreased significantly. TS-1 and lentinan combination immunotherapy was carried out safely with advanced recurrent gastric cancer. In order to examine the usefulness of LNT combined use, it was thought that a randomised trial using toxicity with not only efficacy but QOL and immunological parameters as indicators would be beneficial.