Histoclinical study of nephroblastoma in relation to current and previous SIOP Classification of Renal Tumors of Childhood.

Histological classifications are essential for prognosis in children malignancies. Currently, the histological type of tumor is one of the main prognostic factors in this group. We investigated histoclinical features of nephroblastoma in relation to SIOP 93-01 and SIOP 2001 Classifications of Renal Tumors of Childhood. We examined all the routinely available histological features and histological nephroblastoma types and investigated their influence on patients' survival with the use of log-rank test and Kaplan-Meier method. The results of statistical analysis indicated that SIOP 93-01 more precisely separated nephroblastoma types according to their biology and malignant potential. We also observed that epithelial type of nephroblastoma showed a mixture of results typical for both intermediate and high risk tumors. What is more, we noticed statistically important correlations between developmental defects found in patients with nephroblastoma and tumor volume and the course of disease.