Classification and Prognosis in Wilms's Tumor

The prognosis in Wilms's tumor has changed impressively for the better in the last decade and a half. Series reported in recent years have served to dispel the gloomy attitude that used to be coupled with this neoplasm, and progress has been made in the recognition of characteristics of the disease likely to be associated with a successful result. This favorable trend is the fruit of the intense interest evoked by the lesion and has taken place in the face of the serious handicap presented by its rarity. According to Glenn and Rhame (4) the tumor has an incidence of about 2 new cases per year per million population, which leads to a paucity of material available for study even in large institutions. This naturally creates inconsistencies in the interpretation of the prognostic significance of features of the disease and in the evaluation of treatment. In the hope of assisting in the clarification of such issues, this brief report undertakes an analysis of our cases. At the Charity Hospital of Louisiana in New Orleans 48 cases of Wilms's tumor were treated during the years 1939 to 1958. Of these, 41 had been previously untreated, 3 were referred for radiation therapy immediately following nephrectomy elsewhere, and 4 were seen with reactivation of the disease after full treatment at another institution. These are consecutive unselected cases with histologic confirmation at either operation or autopsy; no cases have been excluded. At the end of two years of observation 15 patients were alive, thereby yielding an absolute survival rate of only 31 per cent which nevertheless does not differ significantly from the fine results reported by Gross and Neuhauser (5)—47 per cent in 38 cases. The 4 recurrent cases had a mean survival time of only six weeks after admission; since they represent a special problem in treatment, quite different from the rest, they will not be included further in the analysis. The other 44 patients had a median survival time of one year. One is untraced after seventeen months and 1 died of diphtheria fourty-four months after treatment for Wilms's tumor. In both instances the patient appeared free of recurrent disease at the time of the last visit to our clinic. The use of two-year rates in evaluating the results in this disease is justified by the survival trend. One-half of all the deaths that have been observed occurred before the end of six months; by the end of the first year 76 per cent of all the failures had taken place and by the end of the second year 97 per cent had been recorded. No deaths from cancer have been observed thus far beyond the third year of follow-up, though 11 patients have been well five or more years, 7 ten or more years, and 2 have been under observation for over twenty years. There is ample documentation in the literature confirming this pattern. For example, in 42 cases studied by Lattimer, Melicow, and Uson (10) 85 per cent of the deaths took place within two years, and in the larger group of 575 cases with survival data compiled by Klapproth (8) from the literature, 95 per cent of the deaths took place in the same interval of time.