Gemcitabine-based combination therapy compared with gemcitabine alone for advanced pancreatic cancer： a meta-analysis of nine randomized controlled trials

BACKGROUND： Pancreatic cancer is one of the most aggressive malignancies and chemotherapy is an effective strategy for advanced pancreatic cancer. Gemcitabine （GEM） is one of first-line agents. However, GEM-based combination therapy has shown promising efficacy in patients with advanced pancreatic cancer. This meta-analysis aimed to compare the efficacy and safety of GEM-based combination therapy versus GEM alone in the treatment of advanced pancreatic cancer.DATA SOURCES： A comprehensive search of literature was performed using PubMed, EMBASE, Web of Science and Cochrane Central Register of Controlled Trials. A quantitative meta-analysis was performed based on the inclusion criteria from all eligible randomized controlled trials. The outcome indicators included overall survival （OS）, 6-month survival, 1-year survival, progression-free survival/time-to-progression （PFS/TTP）, and toxicities. RESULTS： A total of nine randomized controlled trials involving 1661 patients were included in this meta-analysis. There was significant improvement in the GEM-based combination therapy with regard to the OS （HR=0.85, 95% CI： 0.76-0.95, P=0.003）, PFS （HR=0.76, 95% CI： 0.65-0.90, P-0.002）, 6-month survival （RR=1.09, 95% CI： 1.01-1.17, P=0.03）, and the overall toxicity （RR=l.68, 95% CI： 1.52-1.86, P〈0.01）. However, there was no significant difference in the 1-year survival.CONCLUSIONS： GEM-based combination chemotherapy might improve the OS, 6-month survival, and PFS in advanced pancreatic cancer. However, combined therapy also added toxicity.