[Late phase II study of S-1 in patients with advanced head and neck cancer].

A late phase II clinical study of S-1, a novel oral antitumor agent of fluorinated pyrimidines, in patients with advanced/recurrent head and neck cancer was conducted in 25 institutions across Japan as a multi-institutional cooperative study from August 1995 to March 1998. Out of 59 eligible patients, the objective responses were 4 complete responses (CR) and 13 partial responses (PR). The response rate was 28.8% (17/59, 95% CI: 17.8-42.1%). The response rate in previously treated patients was 28.3% (15/53), whereas that in treatment naive patients was 33.3% (2/6). The response rate in patients with prior chemotherapy was 26.7% (12/45). Major adverse reactions of grade 2 or more were anemia (25.4%, 15/59), leucopenia (22.0%, 13/59), neutropenia (25.4%, 15/59), thrombocytopenia (3.4%, 2/59), anorexia (6.8%, 4/59), nausea/vomiting (1.7%, 1/59), stomatitis (1.7%, 1/59), skin symptoms including eruptions or desquamation (5.1%, 3/59), and malaise (1.7%, 1/59). Grade 4 anemia was observed in one case; however, this returned to the normal level after the termination of drug administration and the blood transfusion. Therefore, this event was confirmed to be reversible. Based on these results, we conclude that S-1 is an active agent for the treatment of advanced/recurrent head and neck cancer.