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

BackgroundThe 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.MethodsAn 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.ResultsThe 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.ConclusionsLow/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.