combined modality therapy of pediatric wilms' tumor in upper egypt: a retrospective study

background : we conducted a retrospective analysis to investigate the clinical outcome of combined modality therapy using multiagent chemotherapy, nephrectomy, and radiotherapy in treatment of children with wilms' tumor. methods : this study was conducted on 91 cases of newly diagnosed wilms' tumor from january 2001 until february 2012. patients were categorized into two groups according to treatment approach: i) preoperative chemotherapy with delayed surgery (group a; n=66) and ii) immediate surgery (group b; n=25). results : preoperative chemotherapy showed a 54.5% partial response rate in group a patients. a final stage distribution indicated that the majority of patients (64%) from both groups were considered to be in the early disease stages (i and ii). the median follow up was 49 months (range 3-124). the five-year overall survival rate was 66.5%, whereas the event-free survival rate was 62.5%. in univariate analysis, factors associated with statistically significant reduction in overall (p24 months was associated with a significant reduction in the overall survival rate (p=0.038, hr: 0.438, 95% ci: 0.192-0.953), but was not significant in terms of event- free survival (p=0.104, hr: 0.539, 95% ci: 0.256-1.136). age >24 months (p=0.0095), disease stage (p=0.0014), and blastimal subtype (p=0.006) were associated with significant increases in relapse rate. conclusion : preoperative chemotherapy resulted in a final stage redistribution that placed the majority of patients in the early stages of the disease. age at diagnosis, disease stage, and histological subtype significantly affected survival and relapse rates.