Bilateral Wilms' tumor: Mansoura multi-centers 15 years experience

Bilateral Wilms' tumor (WT) is a challenge. Aggressive surgical resection is needed to prevent recurrence. We revised the clinico-epidemiological criteria of bilateral WT patients in our locality and relation to outcome.

462 WT patients were registered in three medical centers at Mansoura, Egypt. Twenty five patients had bilateral WT whose medical records were revised for all clinico-epidemiologic data plus treatment details, toxicity, and outcome.

The mean age was 34.5 months; 64% of cases were female. Abdominal mass was the commonest presentation (72%). Congenital anomalies were reported in two cases (one case showed hemihypertrophy and the other showed aniridia). About 60% had favorable pathology. Nineteen cases had synchronous bilateral WT (76%) and the remaining (six cases) had metachronous tumors. For the synchronous cases, the response rate to preoperative chemotherapy was 79% and nephron sparing surgery for the least involved kidney was possible in all. Survival rate was 74%. Metachronous tumor management included nephrectomy followed by chemotherapy for the initially diagnosed tumors. However, nephron sparing surgery of the contralateral tumors following preoperative chemotherapy was possible in two cases and the survival rate was 33%. No renal failure or any therapy-related complications were reported.

Bilateral WT is predominantly synchronous with favorable histology, with female predilection and possibly congenital anomalies. Preoperative chemotherapy followed by nephron sparing surgery has a favorable outcome with preserved renal function especially in patients with synchronous WT. Response to preoperative chemotherapy had a statistically significant prognostic impact.