Nephrogenic adenoma of the urinary bladder--a case report and review of the literature.

Nephrogenic adenoma is a rare benign lesion of the urinary tract involving mainly the urinary bladder. The clinical manifestations, endoscopic signs and histopathological pattern of NA should be differentiated from a cancer, which may be a source of misinterpretation. Here we report a case of a 70-year-old man previously treated for papillary urothelial carcinoma. Six months later he developed a tumour, giving rise to a suspicion of recurrence. Histopathologically the tumour was diagnosed as nephrogenic adenoma. It is the first case of nephrogenic adenoma in Polish literature.