Cytomorphological Effects of Mitomycin C on Urothelial Cells: Eosinophils May Be Clue to the Drug-Induced Changes

Cytomorphological changes of mitomycin c on urothelial cells may be misinterpretedas a neoplastic process. a 60-year old male patient who was given an eight-weekcourse of intravesical mitomycin c due to non-invasive low grade transitional cellcarcinoma. during his follow-up care, the findings of a urine cytology exam were asfollows: nuclear enlargement of cells, wrinkled nuclear membranes, little hyperchromasia,pleomorphism, abnormal nuclear morphology and disordered orientation ofthe urothelium. furthermore, there were eosinophils nearby the atypical cells. thisreport aimed at reminding the cytomorphologic changes of mitomycin c may be misinterpretedas carcinoma, so the presence of eosinophils is required to predict thedrug-induced changes.