Nephroblastoma (Wilms tumor): tubule density and prognosis.

Relative differences in tubules density of the primary tumors have been suggested to be prognostically useful in nephroblastoma (Wilms tumor). Forty cases from our institution were retrospectively graded according to tubule density. There were significant differences in disease-free survivals between histologic grades. When compared to other clinical and pathologic staging criteria, tubule density was not more useful prognostically than the staging systems tested. However, when used in conjunction with clinical or pathologic stage, tumor grade improved prognostic sensitivity. Regardless of grade or stage, patients less than 24-months-old at diagnosis had better disease-free survival.