Nephrogenic adenoma of the ureter.

Nephrogenic adenoma (NA) is an uncommon benign lesion of the urothelial tract. The diagnostic features that are useful in the recognition of this benign entity are: the characteristic mixture of various architectural patterns, associated stromal edema and inflammation, hyaline sheath around tubules, and lack of mitotic activity. Although NA appears with hematuria or obstruction, frequently found incidentally in endoscopy or imaging modalities.