Background: From the results of the JCOG9912 and SPIRITS trials, S-1 plus cisplatin (CDDP) therapy (SP) has been recognized as the standard chemotherapy for advanced gastric cancer in Japan. However, in their subsets of patients with the target lesion, irinotecan (CPT-11) plus CDDP therapy (IP) resulted in longer survival than 5-fluorouracil alone while SP exhibited a survival similar to S-1 alone. The objective of this study was to clarify the safety and efficacy of these two regimens.
Methods: Forty-four patients were treated with IP and 32 with SP between September 2002 and July 2006 at Shizuoka Cancer Center. In IP, 70 mg/m(2) CPT-11 was administered on Days 1 and 15, 80 mg/m(2) CDDP on Day 1, repeated every 4 weeks. In SP, 40-60 mg S-1 depending on the patient's body surface area was given orally twice daily for 21 days and 60 mg/m(2) CDDP intravenously on Day 8, repeated every 5 weeks.
Results: The response rate, progression-free survival and median survival were 47% (17 of 36), 170 and 444 days in IP, and 80% (21 of 26), 235 and 469 days in SP. In patients with target lesions, those were 47%, 170 and 431 days in IP, and 80%, 235 and 442 days in SP. The incidence of Grade 3 or 4 toxicity was similar in both groups, but patient refusal of treatment was more frequent for IP than for SP.
Conclusions: Our results demonstrate a better efficacy and feasibility of SP than IP for advanced gastric cancer patients, with or without a target lesion.