RRM1 expression and clinical outcome of gemcitabine-containing chemotherapy for advanced non-small-cell lung cancer: A meta-analysis

Background: The predictive value of RRM1 to therapeutic efficacy of gemicitabine-containing chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC) remains disputable. This meta-analysis is performed to systematically evaluate whether RRM1 expression is associated with the clinical outcome of gemcitabine-containing regimen in advanced NSCLC. Methods: An electronic search was conducted using the databases Pubmed, Medline, EMBASE, Cochrane library and CNKI, from inception to May, 2011. A systemic review of the studies on the association between RRM1 expression in advanced NSCLC and clinical outcome of gemcitabine-containing regimen was performed. Pooled odds ratios (OR) for the response rate, weighted median survival and time to progression were calculated using the software Revman 5.0. Results: The search strategy identified 18 eligible studies (n = 1243). Response rate to gemcitabine-containing regimen was significantly higher in patients with low/negative RRM1 (OR = 0.31, 95% CI 0.21-0.45, P<0.00001). NSCLC patients with low/negative RRM1 who were treated with gemicitabine-containing regimen survived 3.94 months longer (95% CI 2.15-5.73, P<0.0001) and had longer time to Progression for 2.64 months (95% CI 0.39-4.89, P = 0.02) than those with high/positive RRM1. Conclusions: Low/negative RRM1 expression in advanced NSCLC was associated with higher response rate to gemcitabine-containing regimen and better prognosis. Large phase III randomized trials are required to identify whether RRM1 detection is clinically valuable for predicting the prognosis and sensitivity to gemcitabine-containing regimen in advanced NSCLC. (C) 2011 Elsevier Ireland Ltd. All rights reserved.