Role of gemcitabine-based combination therapy in the management of advanced pancreatic cancer: A meta-analysis of randomised trials

Background: Pancreatic cancer is the fourth leading cause of cancer-related death worldwide. Gemcitabine is the mainstay treatment for advanced disease. However, almost all up-to-date trials, that evaluated the benefit of gemcitabine-combination schedules, failed to demonstrate an improvement in overall survival (OS). In this study, we performed a systematic review and a meta-analysis of randomised clinical trials (RCTs) to investigate the efficacy and safety of gemcitabine-based combination regimens as compared to gemcitabine alone in the management of pancreatic cancer. Methods: Clinical trials were collected by searching different databases (PubMed, Embase and the Central Registry of Controlled Trials of the Cochrane Library) and abstracts from major cancer meetings. We considered period ranging from January 1997 to January 2012. Primary end-point was OS, secondary end-points were response rate (RR), disease control rate (DCR) and safety. Hazard ratios (HRs) of OS, odds-ratios (ORs) of RR, DCR and risk ratios of grade 3-4 toxicity rates (TRs), were extracted as presented in retrieved studies and used for statistical analysis. Meta-analytic estimates were derived using random-effects model. Findings: Thirty-four trials for a total of 10,660 patients were selected and included in the final analysis. The analysis showed that combination chemotherapy confers benefit in terms of OS (HR: 0.93; 95% confidence interval (CI): 0.89-0.97; p = 0.001). ORs for both RR and DCR demonstrated a significant advantage for combination therapy (OR for RR: 0.60, 95% CI: 0.47-0.76, p < 0.001; OR for DCR: 0.79; 95% CI: 0.66-0.93; p = 0.006). Toxicities were more frequent with the combination treatment and significance in terms of risk ratio was reached for diarrhoea (0.53, 95% CI: 0.36-0.79), nausea (0.74, 95% CI: 0.56-0.96), neutropenia (0.71, 95% CI: 0.59-0.85) and thrombocytopenia (0.57, 95% CI: 0.43-0.75). Interpretation: The combination chemotherapy as compared to gemcitabine alone significantly improves OS in advanced pancreatic cancer (APC). However, this advantage is marginal whereas the treatment-related toxicity is increased, suggesting the use of gemcitabine-based combination regimens only in selected patient populations. New prospective trials, based on translational approaches and innovative validated biomarkers, are eagerly awaited on this topic. (C) 2012 Elsevier Ltd. All rights reserved.