Background: The aim of this study was to evaluate the clinical usefulness of urinary cytology in the follow-up of patients who under-went surgery for bladder cancer. Particularly, the positive predictive value of urinary cytology and time elapsed between a positive test and the diagnosis of a cystoscopically confirmed bladder tumor are analyzed.
Methods: This study was carried out at the Cytological Laboratory Department of Experimental Medicine and Pathology, University La Sapienza, Rome. Among 230 cases studied since 1996, 30 male patients over 50 were examined (25 with a previous bladder cancer and 5 with a previous prostate cancer) with long time follow-up, who underwent more than two cytological examinations on voided urine (2-12) at pre-fixed intervals.
Results: Nine (30%) of the patients suffered from recurrent disease. The cytological examinations was positive in 8 out of the 9 positive cases and negative in 17 out of the 21 negative cases. Absence of disease was confirmed in all the latter cases both by cystoscopic examination and clinical follow-up. One negative case showed clearly malignant cells in more than one specimen taken at different time intervals. This patient is actually under strict control. In 5 cases atypical metaplasia was present in the cytological specimen. In two of those cases cystoscopic examination 5 and 8 months later confirmed progressive disease. In the other three cases cystoscopy showed no evidence of disease. Two of the patients are well and alive after 2 and 14 months respectively. One is dead of prostatic cancer.
Conclusions: Considering the cases of atypical metaplasi as positive the cytological examinations showed 100% sensibility, 81% specificity, a predictive negative value of 1 and a predictive positive value of 0.66.