Treatment strategy for nodular renal blastema and nephroblastomatosis associated with Wilms' tumor.

Nodular renal blastema and nephroblastomatosis were present in 8 of 118 patients (6.8%) with Wilms' tumor. Five of these 8 patients (63%) had bilateral Wilms' tumors. Two had hemihypertrophy. Preoperative renal angiograms were accurate in detecting these metanephric anomalies. The surgical approach consisted of removal of the most diseased kidney and biopsy for diffuse tumors and wedge resections for localized tumors for the remaining kidney. Postoperatively, radiation was administered when tumor extended outside the kidney. Chemotherapy consisted of vincristine and dactinomycin for 18 mo and adriamycin for 6 mo. This method of management resulted in tumor-free survival of these 8 patients for 1--44 mo (median 24 mo). Nodular renal blastema and nephroblastomatosis may possibly develop into Wilms' tumor. All of these three conditions respond to surgery, chemotherapy, and radiation. When a Wilms' tumor is encountered, it is better to explore and possibly biopsy the opposite kidney. There is a place for second-look laparotomy in this spectrum of congenital anomalies.