Therapy-associated Urothelial Atypia : Cyclophosphamide

This 58 y/o female patient received cyclophosphamide therapy for Wegener's granulomatosis and developed gross hematuria. Cystoscopy showed hemorrhagic and congested urothelium. Biopsy shows nuclear irregularity, hyperchromasia, and multinucleation. Cases of secondary urothelial carcinoma-in-situ have been reported following cyclophosphamide therapy making the distinction between reactive and neoplastic changes challenging.