Catching up with history: treatment of Wilms' tumor in a developing country.

Despite the tremendous progress that pediatric oncology has achieved in the treatment of Wilms' tumor over the last several decades, survival rates in our institution before 1970 did not exceed 8%. In order to correct the problem standardized therapy was instituted in 1970 through a multimodal oncological team. Results using the new approach were reviewed in 1979 (50 patients) and showed an overall 34% 2-year survival rate. Although encouraging, these results were still far below the ones reported in the literature. This prompted us to use a vigorous professional and lay educational program in the city. Treatment methods were replaced by those advocated by the Second National Wilms' Tumor Study. A second evaluation period initiated in 1979 and extended through 1984 (35 patients) yielded an overall 83% survival rate. A retrospective study of the two periods by univariate and multivariate survival analysis revealed that, although much of the improvement in survival could be attributed to a shift in stage distribution towards earlier disease, the admission period itself had an important additional explanatory effect with respect to survival. This was probably due to the improvement in treatment protocols used in the latter period. Age was a prognostic variable only for patients admitted during the 1979-1984 period.