Combined Modality Therapy of Pediatric Wilm's Tumor in Upper Egypt: A Retrospective Study

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. 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). 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 (P<0.0001) and event-free survival (P=0.0001) rates included advanced disease stages (P<0.0001 for both) and blastimal subtype (P=0.0067 for overall survival; P=0.012 for event-free survival). Age of >24 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 eventfree 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. 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.