Purpose: The aim of this study was to perform a clinicopathologic evaluation of a single pediatric institution renal tumor series. Most patients were treated within the frame of 3 consecutive SIOP trials, which included preoperative chemotherapy as their main feature.
Methods: Medical records and diagnoses of 111 patients were reviewed. The association of pathologic features with outcome was investigated by means of the Kaplan-Meier method, the Cox model, and a logistic multivariate analysis. Comparison among different trial results was carried out.
Results: In 98 patients (88%), nephroblastoma was diagnosed, followed by 6 adult-type renal tumors, 3 cystic nephromas, 2 mesoblastic nephromas, and 2 clear cell sarcomas. For nephroblastoma, a statistically significant correlation between grade and both disease-free survival rate and 5-year survival rate, and between stage and overall survival rate was shown. Lymph node involvement, local relapse, nephrogenic rests, and older age at presentation appeared to be less important prognostic factors. Tumor spillage was very sensitive to chemo or radiotherapy. No significant difference in outcome was observed among different trials.
Conclusions: Wilms' tumor was the most frequent neoplasm and resulted in a 5-year cure rate of 90%. Clinical course was influenced mainly by diffuse anaplasia and, to a minor extent, by lymph node involvement. Because some tumors followed an unpredictable course, it is likely that also other biological factors played a significant role.
Copyright 2001 by W.B. Saunders Company.