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 ۹۱ cases of newly diagnosed Wilms' tumor from January ۲۰۰۱ until February ۲۰۱۲. Patients were categorized into two groups according to treatment approach: i) preoperative chemotherapy with delayed surgery (group A; n=۶۶) and ii) immediate surgery (group B; n=۲۵).Results: Preoperative chemotherapy showed a ۵۴.۵% partial response rate in group A patients. A final stage distribution indicated that the majority of patients (۶۴%) from both groups were considered to be in the early disease stages (I and II). The median follow up was ۴۹ months (range ۳-۱۲۴). The five-year overall survival rate was ۶۶.۵%, whereas the event-free survival rate was ۶۲.۵%. In univariate analysis, factors associated with statistically significant reduction in overall (P۲۴ months was associated with a significant reduction in the overall survival rate (P=۰.۰۳۸, HR: ۰.۴۳۸, ۹۵% CI: ۰.۱۹۲-۰.۹۵۳), but was not significant in terms of event- free survival (P=۰.۱۰۴, HR: ۰.۵۳۹, ۹۵% CI: ۰.۲۵۶-۱.۱۳۶). Age >۲۴ months (P=۰.۰۰۹۵), disease stage (P=۰.۰۰۱۴), and blastimal subtype (P=۰.۰۰۶) 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.