A complicated case of bilateral cystic nephroma in a 16-month-old boy.

We describe a case of a progressive bilateral cystic nephroma (BCN) in a child undergoing a multistaged surgical procedure. After partial resection of the left sided tumor, a progress occurred on that side and the left kidney had to be removed 10 weeks later. After 35 months a tumor progression was observed on the right side together with an ureteral obstruction leading to a decreased renal function. In a third operation a complete tumor resection on the right side was achieved through longitudinal partial nephrectomy, reconstruction of the renal pelvis, and reanastomosis of the reconstructed pelvis and ureter. The patient showed no evidence of the disease at 28 months of follow-up. The presented case provides an evidence that in BCN a tumor progress may occur after multistaged surgical approaches. A single-staged complete tumor resection with renal salvage techniques seems indicated.