The National Wilms Tumor Study: a 40 year perspective.

The National Wilms Tumor Study (NWTS) was the first pediatric intergroup clinical research unit in North America. It was thus able to collect data concerning children with malignant kidney tumors from each of the then-extant childhood cancer cooperative study groups. Enough patients-about 350 per year-could thus be gathered to study the nature and clinical characteristics of the various kidney malignant tumors of childhood. It also enabled randomized trials of comparative treatment regimens, patients stratified following stipulated risk criteria. The result has been a steadily increasing two-year survival rate to the 90% level while at the same time modulating the intensity of therapy according to well-defined needs. For example, routine post-operative radiation therapy, damaging to normal as well as neoplastic tissues, has been largely eliminated. The proportion of patients given doxorubicin, a cardiotoxic drug, also has been curtailed. These two therapies are now restricted to the 30% of patients who have more advanced or more aggressive disease. All this has been driven to meet the challenge inherent in the motto of pediatric oncology: "Cure is not enough"; that is, the cured child of to-day must not become the chronically ill adult of tomorrow, suffering from the delayed complications secondary to unnecessary, toxic therapies.