Irinotecan monotherapy offers advantage over combination therapy with irinotecan plus cisplatin in second-line setting for treatment of advanced gastric cancer following failure of fluoropyrimidine-based regimens.

The optimal regimen of chemotherapy for gastric cancer in a second-line setting remains to be clarified. The aim of this retrospective study was to evaluate the efficacy and safety of second-line irinotecan treatment. A total of 134 patients with gastric cancer who had received prior chemotherapy with fluoropyrimidine-based regimens were treated with irinotecan (150 mg/m(2) on days 1 and 15) alone every 4 weeks (Arm I) or irinotecan (70 mg/m(2) on days 1 and 15) plus cisplatin (80 mg/m(2) on day 1) every 4 weeks (Arm IP) between April, 2004 and March, 2009. Patient characteristics, response rate, progression-free survival, overall survival and safety were investigated. Of 134 patients with recurrent or unresectable gastric cancer, 92 were treated in Arm I and 42 patients in Arm IP. Overall response rate in Arm I was 8.1%, compared with 20.0% in Arm IP (P=0.65). Median progression-free survival (Arm I vs. IP; 2.6 vs. 2.7 months, P=0.73) and median overall survival (Arm I vs. IP; 9.8 vs. 8.0 months, P=0.67) did not differ between the two treatment groups. Neutropenia, leukopenia and anorexia were the most common grade 3/4 adverse events, occurring significantly more frequently in Arm IP than in Arm I (P<0.05). Irinotecan may be a key agent, and serial irinotecan monotherapy is more beneficial as compared to irinotecan plus cisplatin in the treatment of advanced gastric cancer in second-line settings. Irinotecan monotherapy is beneficial compared to irinotecan plus cisplatin in second-line settings for the treatment of advanced gastric cancer refractory to fluoropyrimidine-based regimens.