Invasive Urothelial Carcinoma Presenting With Combined Obstructive Uropathy and Ischemic Small- and Large-Bowel Obstruction.

Intestinal involvement by urothelial malignancy is uncommon and can obscure the primary diagnosis. We report a woman in her 70s who presented with shock, profound anemia, acute kidney injury, and bilateral hydronephrosis caused by a necrotic pelvic mass suspected to arise from the bladder. Despite resuscitation and urinary decompression, she developed abdominal distention, rising lactate levels, and respiratory decline. Exploratory laparotomy revealed combined small- and large-bowel obstruction with ischemic bowel caused by an invasive pelvic mass. Pathology from the resected small bowel showed poorly differentiated urothelial carcinoma with basal/squamous features. This case highlights an unusual presentation of advanced urothelial malignancy.