Recurrence of Urothelial Bladder Carcinoma in the Colon Presenting as Hematochezia.

Patients with superficial bladder cancers remain clinically indolent after treatment with even a modicum of urologic intervention. However, with more invasive disease, the majority of patients experience recurrence. The conventional route of metastasis and recurrence in primary urothelial cell carcinoma is through lymphatic system, with regional lymph nodes, lungs, liver, brain, and bone being the most common sites. Isolated intraluminal colonic recurrence in the absence of local invasion is extremely rare. We report a unique case of urothelial cell carcinoma presenting with an isolated colonic mass, which unexpectedly, on immunohistostaining, proved to be primarily of urothelial rather than colonic origin.