Sigmoid-Urachal-Vesical Fistula Associated with Urothelial Carcinoma in an Adult Male: Case Report

often subject to infection, spontaneous rupture, fistula formation or a malignant change. Sigmoid-urachal fistulas have been reported in cases of colonic diverticulitis or an infected urachal cyst (1-3); however, for these cases, there is no communication with the urinary bladder or any association with urothelial carcinoma. Although the normal urachus is most commonly lined by the transitional epithelium, an urachal carcinoma predominantly manifests as an adenocarcinoma. Urothelial carcinoma is extremely rare (4-6). We report an unusual case of a sigmoid-urachal-vesical fistula associated with urothelial carcinoma in an adult male. For accurate diagnosis and treatment planning, radiologists should consider the presence of a coexistent malignant lesion in a complicated urachal remnant.