Primary ureteral mucinous adenocarcinoma with xanthogranulomatous pyelonephritis masquerading as a giant renal mass

Primary ureteral carcinoma is rare among all urogenital malignancies, with transitional cell carcinoma being the most common histology followed by squamous cell carcinoma. Adenocarcinoma is extremely rare. Herein, we report a case of primary mucin secreting adenocarcinoma of the right lower ureter in a 67-year-old male. Contrast-enhanced computed tomography (CECT) scan showed a large cystic mass occupying the whole abdomen along with a mass in the lower third of the right ureter mimicking as a giant renal mass. Ureteroscopy followed by laparotomy including right nephroureterectomy with bladder cuff excision was performed. On histopathological examination, the CECT scan-based suspected giant renal mass revealed to be xanthogranulomatous pyelonephritis of the kidney along with primary mucin secreting adenocarcinoma of the ureter.