Vesical nephrogenic adenoma: an unusual presentation of a bladder tumour.

Vesical nephrogenic adenoma is a rare, benign entity that appears most commonly in middle-aged males. Its etiology is unknown, but it has been linked to chronic irritating factors, such as infection, trauma, urological surgery, kidney stones, foreign bodies and chemical agents, such as Bacille Calmette-Guerin. We report 2 new cases with a history of transurethral resection of the bladder and the prostate and a history of prolonged voiding symptoms. In both cases, the findings of encysted tubular structures lined with flattened cuboidal cells without atypia were consistent with the diagnosis of vesical nephrogenic adenoma.