The eligibility criteria included (1) histologically confirmed metastatic or recurrent gastric cancer; (2) at least one measurable lesion; (3) an age of ≥18; (4) adequate oral intake; (5) no previous antitumor therapy within 5 years (adjuvant chemotherapy without S-1 was allowed if finished ≥6 months before enrollment); (6) an Eastern Cooperative Oncology Group performance status <2; and (7) adequate bone marrow, hepatic, and renal function.