Post-progression survival following second-line chemotherapy in patients with advanced pancreatic cancer previously treated with gemcitabine: a meta-analysis

Background Post-progression survival (PPS) could be a confounding element in interpreting data from clinical trials of second-line chemotherapy in patients with advanced pancreatic cancer (PC) previously treated with gemcitabine (GEM) because a recent meta-analysis of oxaliplatin combination therapy showed statistical heterogeneity for overall survival (OS) but not for progression-free survival (PFS). This study aimed to improve the understanding of the impact of PPS on OS in this setting. Methods Databases were searched to identify randomized controlled trials (RCTs) in the salvage setting. We evaluated relationships between OS and PFS, PPS, and other variables. Results Totally, 17 RCTs with 3253 patients were identified. Median OS was strongly and moderately associated with median PPS and PFS, respectively (r=0.913; p<0.001 and 0.780; p<0.001, respectively). The proportion of patients with good performance status was significantly associated with both PPS and PFS (r=0.574, p<0.001 and 0.492, p<0.001, respectively). The induction rate of subsequent chemotherapy was related to the duration of PPS and OS (r=0.640, p<0.001 and 0.647, p<0.001, respectively). Median PPS and OS were significantly longer in recent trials than those in older trials (3.55 versus 2.78months, p<0.001 and 6.29 versus 5.02months, p<0.001). Conclusions Median PPS was strongly correlated with median OS. Given the recently increased opportunity for subsequent chemotherapy and supportive care, PPS may serve as an important element to clarify problems in this setting.