The accuracy of urinary cytology in daily practice

BACKGROUND. Most studies of urinary cytology have been research analyses de signed to test the method itself, and many claim that the high diagnostic y ields in these studies cannot be achieved in daily practice, The authors ex amined the clinical and pathologic records in three hospital pathology prac tice settings-academic, community, and cancer referral settings-to determin e the diagnostic yield of urinary cytology under daily clinical conditions. METHODS. Records of consecutive urinary cytology specimens from 1672 patien ts reported from the years 1990-1994 were reviewed and correlated with hist ologic and clinical information, Initial analyses were based on the records themselves, without review of pathologic specimens. Subsequently, a subset of specimens was reviewed to determine reasons for noncorrelations. RESULTS. Results confirmed that the diagnostic sensitivity and specificity of urinary cytology for high grade transitional cell neoplasms, as reported in the daily practice of pathology, are very high (79% and >95%, respectiv ely). Disaggregated cells from low grade transitional cell neoplasms usuall y lack recognizable features of neoplasia, and attempts to classify such le sions cytologically result in low diagnostic yield, with an overall sensiti vity of 26%. Of these 1672 patients, 707 had insufficient clinical informat ion for analysis, despite diligent and persistent efforts to acquire it. CONCLUSIONS. The diagnostic yield of consultations based on urinary cytolog y in the daily practice of pathology is high, regardless of whether the pra ctice setting is referral-based or community-based. The available informati on indicates that in approximately 79% of patients with high grade transiti onal cell neoplasms, the neoplasms can he detected using urinary cytology. Conversely, a negative result is predictive of no cancer in more than 90% o f cases. Sensitivity for detecting low grade urothelial lesions is low: how ever, most of these are easily detected cystoscopically. The authors' inabi lity to acquire sufficient information to determine diagnostic yield in a l arge percentage of their cases was disturbing to them. Not only did this de ficiency render their analyses incomplete, but lack of easily accessible fo llow-up and the apparent low priority for quality assurance activities amon g pathologists in all types of practice settings is likely to significantly reduce the feedback required for pathologists to acquire and maintain expe rtise in this very difficult area. (C) 1999 American Cancer Society.