[Adult Wilms' tumor]

Wilms' tumor is a malignant embryonic renal neoplasm that is exceptional in adults. There are not clinical data or radiographic investigations that can distinguish it from renal cell carcinoma. So the diagnostic is based in the pathological evaluation. It may be cystic and must be consider in the differential diagnosis of cystic lesions of the kidney. The prognosis of Wilms' tumor in adults is worse than in children because of the high recurrence, the lower response rate to chemotherapy regimens and the advanced stage at the time of clinical presentation, like an asymptomatic abdominal mass in 75% of the cases. We report a new case of nephroblastoma in a 29 years old woman presenting like a renal colic, with a cystic configuration by abdominal ultrasound initially, that changed into a solid renal mass later. There is not a definitive treatment protocol currently but some authors suggest a combination chemotherapy with carboplatin and etoposide because it is very effective in recurrent or refractory adult Wilms' tumor. Our patient remains asymptomatic and without evidence of recurrence 18 months after the surgery.