Cytology of bladder papilloma.

Eighty-four urinary cytology specimens from 51 patients known to have bladder papilloma were reviewed and compared with 30 specimens from patients without neoplastic urologic disease, 12 specimens from patients later found to have papillomas that were unsuspected at the time of examination and 6 specimens from patients with a history of papilloma but no present evidence of the disease. No specific findings were identified that could be used to make a cytologic diagnosis of papilloma. However, the specimens from patients with papilloma were likely to contain an increased number of exfoliated epithelial cells, including atypically shaped cells that were small and round or, less frequently, elongated; they were also likely to contain a small number of red blood cells. This combination of cytologic findings yielded a pattern that can be described as consistent with or suggestive of papilloma in the appropriate clinical setting. It is not diagnostic since the absence of this cytologic pattern does not rule out papilloma, and the same cytologic features can be found (less frequently) in patients with other urologic diseases.