Survival analysis of treatment with S-1, alone or in combination with CDDP (SP), in elderly patients with advanced gastric cancer: A 10-year retrospective cohort study.

e15170 Background: In Japan, the elderly population is increasing, and steadily increase the number of deaths in the elderly gastric cancer patients. However, the standard treatment of elderly gastric cancer has not been established, either treatment of S-1 or SP is carried out in the clinical practice, while SP is considered as standard therapy in the young people. Now, we investigated the impact of S-1 and SP on survival time in clinical practice. Methods: Between 2003 and 2012, advanced gastric cancer patients over 70 years of age received S-1 or SP as first line therapy were retrospectively reviewed to investigate clinical outcomes. Patient characteristics analyzed included age, gender, performance status (PS), tumor histology, renal function and metastatic site. In addition, we have analyzed prognostic factors in multivariate analysis. Results: Among 93 patients (pts), 67 pts (72%) received S-1 and 26 pts (28%) received SP. Patient characteristics between the two groups showed no significant differences in gender, histology, metastatic site, or creatinine clearance level, but did show an imbalance in PS (tended with better at SP group) and age (tended with younger at SP group), significantly. Even though the background factors were favorable results in SP group, there were no significant differences in median progression-free survival (median 139 vs. 102 days; p = 0.96) and overall survival (median 330 vs. 263 days; p = 0.55) between S-1 and SP group, respectively. Grade 3-4 neutropenia (10 vs. 27%, p < 0.05) , fatigue (3 vs. 15%, p < 0.05) and Grade 1-2 creatinine increased (9 vs. 31%, p < 0.01) were more frequent in the SP group than in the S-1 group, respectively. According to the multivariate analysis, exposure to CDDP was not independently associated with a better prognosis. Conclusions: Despite the obvious limitations of this analysis, there does not appear to be a benefit for the addition of CDDP in the elderly gastric cancer patients due to the increase of toxicity. A randomized controlled trial in this age group is warranted. We will also report the results of clinically meaningful prognostic factors associated with the primary treatment at annual meeting.