Preoperative chemotherapy for Wilms tumor.

Preoperative chemotherapy was administered to 19 children with Wilms tumor judged clinically to be unresectable at M. D. Anderson Hospital between January 1, 1962, and September 1, 1980. After 2 to 4 doses of vincristine, marked reduction in tumor size occurred in 16 patients. After chemotherapy 16 tumors could be resected completely, another required irradiation to reduce the tumor, and only 2 tumors could not be excised. Pathologically the most dramatic changes occurred in the undifferentiated interstitial stroma, followed next by changes in the nodular blastema. Differentiated elements were apparently not affected. No serious complications were attributed to the preoperative drug treatment. This experience suggests that in selected instances preoperative chemotherapy can affectively facilitate the therapy of Wilms tumor.