Progression-free survival and post-progression survival in patients with advanced gastric cancer treated with first-line chemotherapy

The impact of post-progression survival (PPS) on the overall survival (OS) of patients with advanced gastric cancer (AGC) has not yet been reported in detail. We analyzed prospectively collected data from AGC patients who received first-line chemotherapy including fluoropyrimidine plus platinum. We partitioned OS into progression-free survival (PFS) and PPS in each patient and analyzed correlations between OS and either PFS or PPS using the Spearman rank correlation coefficient (rho). A total of 291 AGC patients met the inclusion criteria with median PFS, PPS, and OS of 5.3, 8.1, and 14.8 months, respectively. PFS and OS for each patient showed a correlation of rho = 0.75 [95 % confidence interval (CI) 0.69-0.81]. PPS and OS showed a correlation of rho = 0.87 (95 % CI 0.84-0.91). According to multivariate analysis, performance status at progression, PFS of first-line chemotherapy, and use of second-line chemotherapy were independently associated with PPS. These results indicate that both PFS and PPS are correlated with OS in first-line chemotherapy for AGC, suggesting the importance of reporting detailed patient characteristics and treatment course after disease progression in clinical trials of first-line chemotherapy for AGC.