Role of dactinomycin in the improved survival of children with Wilms' tumor.

Thirty consecutive cases of histologically proved Wilms' tumor followed for a minimum of two years have been reviewed. The overall survival rate was 70%, with 47% beyond the period of risk (Collins'). Of 14 children treated by nephrectomy and postoperative radiotherapy, 43% (6 of 14) are living and apparently free of tumor. Of 13 children treated with dactinomycin in addition to nephrectomy and postoperative radiotherapy, 92% (12 of 13) are living and apparently free of tumor. It was concluded that the survival of children with Wilms' tumor is markedly prolonged by the administration of dactinomycin at the time of diagnosis. The beneficial effect of dactinomycin was attributed to the "cidal" action of this drug on small or poorly established metastases.