| Summary points: | A 25-year-old with nephrogenic adenoma of the bladder that was repeatedly found to be benign on pathological analysis returns for a last resection that shows the former benign adenoma has transformed into a moderately differentiated adenocarcinoma of the bladder. This case report describes the patient's history, various cytological findings, and treatment outcome, and includes several images. The authors review the literature on the malignant entity of nephrogenic adenoma. |