Reduction in tumor burden allowing partial nephrectomy following preoperative chemotherapy in biopsy proved Wilms tumor.

During the last 6 years a treatment protocol of radiographic staging along with percutaneous biopsy to establish a histological diagnosis has been used in 37 patients with Wilms tumor. Combination chemotherapy was given for 4 to 6 weeks before definitive surgical resection. In 9 patients tumor shrinkage was sufficient to permit preservation of a portion of the affected kidney(s). In stage V disease partial nephrectomy was accomplished in 5 patients. In 4 additional patients with unilateral disease downstaging also allowed partial nephrectomy. The radiological and histological changes that allowed this limited surgery are analyzed and compared.