Late effects of treatment for Wilms' tumor.

Twenty-six out of a total of 49 patients who were treated for Wilms' tumor at the Mallinckrodt Institute of Radiology between January 1960 and December 1975 have survived at least five years. The median follow-up time is 153 months (12 years, 9 months). One girl, who received pelvic irradiation, has not reached puberty at age 14, but the other 25 patients are currently in good health and have no major complaints or functional impairments at present. Twenty-one patients have, however, developed some complication at some time since treatment. Serious side-effects requiring hospitalization included one case of pericarditis and one of esophageal varices secondary to portal hypertension. Both these patients, however, had advanced tumors requiring aggressive treatment and their complications should be seen in perspective. There has also been one case of temporary low grade renal failure and one of transient hypertension. More common complications were 14 instances of scoliosis (only three have had any symptoms, however), five of osseous hypoplasia, three of soft tissue hypoplasia, three of liver damage and three of lung damage. There was one case of osteochondroma within a radiotherapy field. The factors pertaining to these complications and the anticancer therapy which preceded them are discussed in detail. We conclude that, whereas structural changes following modern radiotherapy for Wilms' tumor are very common, severe dysfunctions are infrequent. Even more extended periods of observation will be required before the total number of abnormalities is ascertained. However, the striking observation from this study is the lack of late functional effects.