S-1 in the treatment of advanced and recurrent gastric cancer: current state and future prospects.
BACKGROUND
S-1 (TS-1) is a novel oral anticancer drug. Because of the excellent results of phase II studies, we continued to prescribe S-1 for advanced or recurrent gastric cancer after we participated in the phase I and II studies.


METHODS
Twenty-nine patients with advanced or recurrent gastric cancer were treated with S-1. Clinicopathological features, survival, and adverse reactions were analyzed.


RESULTS
One course of treatment consisted of 40, 50, or 60 mg/body twice a day for 28 days followed by withdrawal for 2 weeks. The mean number of treatments was 3.6 courses (range, 1-12 courses). The response rate was 37.9% (11 partial responses [PRs] in 29 patients). Although the response rate of patients who did not receive prior chemotherapy was 47.6% (10 PRs in 21 patients), that of patients with prior chemotherapy was 12.5% (1 PR in 8 patients). The median survival time was 14.1 months, and that of patients who responded to treatment was 22.1 months, which was significantly longer than that of nonresponder patients. One-year and 2-year survivals in the 29 patients were 50.2% and 24.3%, respectively. Adverse reactions were noted in 17 of 29 patients, and the most frequent one was leukocytopenia. Only 2 patients experienced grade 3 leukocytopenia and neutrocytopenia.


CONCLUSIONS
Because of the high response rate and low incidence of severe adverse reactions, S-1 is a first-line chemotherapy that can be used for outpatients, especially for patients without prior chemotherapy. As the response rate for patients with prior chemotherapy was low, combined therapy with S-1 is worth evaluating for these patients.
Takahashi
Ikuo
I
Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
Kakeji
Yoshihiro
Y
Emi
Yasunori
Y
Sakurai
Masato
M
Yonemura
Yusuke
Y
Kimura
Yasue
Y
Maehara
Yoshihiko
Y
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000964:Antimetabolites, Antineoplastic / Q000009:adverse effects / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D004338:Drug Combinations; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use; D005544:Forecasting; D006801:Humans; D007564:Japan; D008113:Liver Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000556:secondary; D008207:Lymphatic Metastasis; D008297:Male; D008727:Methotrexate / Q000627:therapeutic use; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy* / Q000401:mortality; D010094:Oxonic Acid / Q000009:adverse effects / Q000627:therapeutic use*; D011725:Pyridines / Q000009:adverse effects / Q000627:therapeutic use*; D012720:Severity of Illness Index; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000401:mortality; D016019:Survival Analysis; D005641:Tegafur / Q000009:adverse effects / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome
D000964:Antimetabolites, Antineoplastic; D004338:Drug Combinations; D011725:Pyridines; C079198:S 1 (combination); D005641:Tegafur; D010094:Oxonic Acid; D005472:Fluorouracil; D008727:Methotrexate