[Nephrogenic Adenoma : A Case Report].

A 62-year-old woman was diagnosed with bladder urothelial carcinoma in situ. Transurethral resection of bladder tumor (TURBT) was performed, followed by intravesical therapy with bacillus Calmette Guérin. Two months later, a papillary lesion was observed around the scar. The lesion was biopsied, and histological examination revealed papillary and tubular formation with inflammatory cell infiltration. Therefore, the lesion was diagnosed as nephrogenic adenoma. We opted for watchful waiting because the lesion had disappeared and nephrogenic adenoma is a benign tumor. At 6 months after the biopsy of the nephrogenic adenoma, the patient showed no signs of recurrence.