Chemotherapy-related toxicity in infants treated according to the Second National Wilms' Tumor Study.

Babies under 12 months of age have been included in the National Wilms' Tumor Study (NWTS) series of clinical trials. Undue chemotherapy-related toxicity was encountered early during the course of the second NWTS. The prescribed doses of actinomycin D (AMD), vincristine (VCR), and Adriamycin ([ADR] doxorubicin; Adria Laboratories, Columbus, OH) were therefore halved. The frequency of severe hematologic toxic episodes was reduced (30 of 64 or 47% for babies receiving full doses [FD], and six of 48 or 13% for those given reduced doses [RD]). Similar reductions in pulmonary and hepatic effects were noted, and treatment-related deaths were reduced from 6% to 0 for the FD and RD samples, respectively. These frequencies among RD babies were similar to those encountered in 530 older children administered FD. Reduction of dose did not compromise therapeutic effectiveness.