efficacy of preoperative chemotherapy in treatment of children with wilms’ tumor: a meta-analysis

Context: to assess the efficacy of preoperative chemotherapy in wilms’ tumor patients and explore its true value for specific subgroups. objectives: in the presence of these controversies, a meta-analysis that examines the efficacy of preoperative chemotherapy in wilms’ tumor patients and specific subgroups is needed to clarify these issues. the objective of this meta-analysis is to assess the efficacy of preoperative chemotherapy in wilms’ tumor patients and explore its true value for specific subgroups. data sources: computer-based systematic search with “preoperative chemotherapy”, “neoadjuvant therapy” and “wilms’ tumor” as search terms till january 2013 was performed. study selection: no language restrictions were applied. searches were limited to randomized clinical trials (rcts) or retrospective studies in human participants under 18 years. a manual examination of references in selected articles was also performed. data extraction: relative risk (rr) and their 95% confidence interval (ci) for tumor shrinkage (ts), total tumor resection (tr), event-free survival (efs) and details of subgroup analysis were extracted. meta-analysis was carried out with the help of the software stata 11.0. finally, four original randomized clinical trials (rcts) and 28 retrospective studies with 2375 patients were included. results: for preoperative chemotherapy vs. up-front surgery (pc vs. su) group, the pooled rr was 9.109 for ts (95% ci: 5.109 - 16.241; p < 0.001), 1.291 for tr (95% ci: 1.124 - 1.483; p < 0.001) and 1.101 for efs (95% ci: 0.980 - 1.238; p = 0.106). for subgroup short course vs. long course (sc vs. lc), the pooled rr was 1.097 for ts (95% ci: 0.784 - 1.563; p = 0.587), 1.197 for tr (95% ci: 0.960 - 1.493; p = 0.110) and 1.006 for efs (95% ci: 0.910 - 1.250; p = 0.430). conclusions: short course preoperative chemotherapy is as effective as long course and preoperative chemotherapy only benefits wilms’ tumor patients in tumor shrinkage and resection but not event-free survival.