Accuracy of urinary cytology in the diagnosis of primary and recurrent bladder cancer.

Two thousand two hundred thirteen smears of urinary specimens from 263 patients with bladder disorders were reviewed and the results correlated with the clinical status at the time of urine collection and with the histologic diagnosis during follow-up. In all cases a cytologic diagnosis of malignancy was histologically confirmed at follow-up, reflecting the high predictive value of a positive result in cytology. Cytologic diagnoses were also analyzed for the interval between the cytologic and histologic diagnosis of malignancy. In cases of cytologic diagnosis of malignancy, at times without a clinical suspicion of severe abnormality, an interval of up to 691 days was registered before a malignant process was confirmed histologically. Furthermore, the influence of tumor grade and mode of therapy on the diagnostic accuracy of urinary cytology was evaluated. The accuracy of urinary cytology differed clearly between untreated and treated patients with both high and low grade tumors. Patients who received surgical therapy, radiotherapy and chemotherapy were grouped into three groups. Accuracy of cytologic diagnosis was calculated in relation to variations in therapy and in tumor grade. Minor differences in accuracy were found between specimens from patients after surgical therapy, chemotherapy and radiotherapy. The data from this study suggest that the diagnostic accuracy of urinary cytology is very much related to the histologic grade of bladder tumors, to pretreatment and posttreatment status, and only minimally to the mode of therapy itself (e.g., radiotherapy, chemotherapy or surgical therapy). The high percentage of cytologic diagnoses of atypia in specimens from patients undergoing chemotherapy and radiotherapy reflects the diagnostic problems.