BackgroundThis multi-center analysis of data from China reviews the management and long-term outcomes of patients with bilateral Wilms tumors (BWT), and explores prognostic risk factors.MethodsWe retrospectively analyzed a cohort of pediatric patients with synchronous BWT treated at 18 pediatric oncology centers in China between 2006 and 2023. The overall survival (OS) and event-free survival (EFS) rates were calculated using Kaplan-Meier methodology. Prognostic risk factors were determined using univariable and multivariable analysis.ResultsA total of 167 patients with BWT and a median age at diagnosis of 13 months (range 0-78 months) were included in the study. Neoadjuvant chemotherapy was administered to 149 index cases; tumor biopsy was performed before initiating chemotherapy in 70 patients. One hundred and three children underwent bilateral nephron-sparing surgery (NSS) and two hundred fifty-two of the three hundred one kidneys underwent NSS. The four-year OS and EFS rates in the study cohort were 86.5% and 77.8%. After a median follow-up of 50 months, four patients developed renal failure requiring dialysis and a single patient received a kidney transplant 26 months postoperatively.ConclusionsRegarding prognostic factors, the results of the multifactor analysis indicate that distant metastasis and positive surgical margins have negative impacts on OS and distant metastasis had a negative effect on EFS. Distant metastasis and positive surgical margins affect the long-term prognosis of BWT.1QNvutR1ca4Y5v-Jz6WysKVideo Abstract (MP4 19393 KB)ConclusionsRegarding prognostic factors, the results of the multifactor analysis indicate that distant metastasis and positive surgical margins have negative impacts on OS and distant metastasis had a negative effect on EFS. Distant metastasis and positive surgical margins affect the long-term prognosis of BWT.1QNvutR1ca4Y5v-Jz6WysKVideo Abstract (MP4 19393 KB)