Urothelial changes induced by therapeutic procedures for bladder cancer. A review.

Topical and systemic therapeutic agents and treatment modalities, such as thiotepa and mitomycin C, cyclophosphamide, bacillus Calmette-Guerin, radiation therapy, photodynamic and laser therapy, and gene therapy, produce a host of changes in the bladder, some of them mimicking cancer. Pathologists must be aware that following these types of treatment, the clinical utility of urinary cytology is reduced.