Tissue polypeptide antigen (TPA) in urinary bladder cancer cytology: a follow-up study

Tissue polypeptide antigen (TPA) has been detected by immunocytochemical assay on urine cytological samples from 28 asymptomatic patients, who previously had a histological diagnosis of papillary transitional cell carcinoma (PTCT) of the urinary bladder (UB), in order to evaluate its role in follow-up controls. TPA staining intensity (SI) in urothelial cells was evaluated to improve the diagnostic accuracy of cytology. Differentiated tumor cells were strongly stained for TPA, heavier than normal urothelial cells. Undifferentiated neoplastic cells were less stained for TPA with a wide range of SI. TPA detection revealed positive cytology in 21 (75%) of the considered cases. The accuracy of our cytological findings compared with both routine examinations and subsequent histopathological diagnosis was of 95.2%. Follow-up urinary cytology limits could be reduced by TPA searching in differentiated tumor cells, deriving from low-grade neoplasms.