Uroepithelial carcinoma in association with cyclophosphamide ingestion.

The association of daily oral cyclophosphamide with the development of transitional cell carcinoma or squamous cell carcinoma of the bladder had been documented. We report the first 2 cases of transitional cell carcinoma of the renal pelvis and an additional 4 cases of transitional cell carcinoma of the bladder following cyclophosphamide ingestion. Patients who have been taking daily oral cyclophosphamide for a prolonged period should have excretory urography, cystoscopy and bladder mucosal biopsies performed as part of a cancer surveillance protocol.