Histochemical evidence for tubule segmentation in a case of Wilms' tumor

A lectin histochemical and immunohistochemical approach was used to compare the different histologic elements of an unusual case of Wilms' tumor with normal kidneys. This case was stained with ten lectin-horseradish peroxidase conjugates; immuno-stained for Tamm-Horsfall glycoprotein, epidermal keratin, and vimentin; and compared with 19 control kidneys. The morphologic and cytochemical properties of various tumor elements in this specimen served to identify them as tumor analogs of all segments of the normal kidney tubules except distal tubules. Evidence for Wilms' tumor differentiation is provided by this case, whose epithelium histochemically resembles normal human epithelial cells.