BACKGROUND: Historically, the diagnostic accuracy of urine cytology for the detection of @entity189 has been low, particularly for low-grade lesions. In 1998, the World Health Organization and International Society of Urologic Pathologists (WHO/ISUP) established a new classification system for @entity5 . It has been postulated that the accuracy of urine cytology for the detection of @entity189 should improve, because the current WHO/ISUP system classifies @entity1494 that lack any significant cytologic atypia as @entity4929 of low malignant potential (PUNLMP). Also, the accuracy of urinary cytology for the detection of high-grade lesions is expected to decrease, because the criteria for high-grade lesions is lowered, placing most of the previous WHO Grade 2 @entity5 into the current high-grade @entity189 category. METHODS: One hundred bladder biopsies that were classified according to the previous WHO classification system were examined by one pathologist and were reclassified according to the new WHO/ISUP scheme. All biopsies had corresponding urine specimens that had been diagnosed previously by a different cytopathologists. The @entity1 ' previous WHO and current WHO/ISUP surgical diagnoses were compared with the corresponding urine cytology. In addition, cytospins obtained from 40 @entity1 with a histologic diagnosis of low-grade @entity189 (n = 20 @entity1 ) and high-grade @entity189 (n = 20 @entity1 ) according to the WHO/ISUP classification system were reviewed to identify any outstanding cytologic features. RESULTS: According to the original WHO classification system, there were 26 @entity1 with @entity1606 ( @entity1606 ), 61 @entity1 with Grade 2 @entity1606 , and 13 @entity1 with Grade 3 @entity1606 . The corresponding cytology was positive in 11 of 26 Grade 1 @entity5 , 28 of 61 Grade 2 @entity5 , and 12 of 13 Grade 3 @entity5 . After the reclassification, there was 1 @entity1185 , 12 PUNLMP lesions, 50 low-grade @entity189 , and 37 high-grade @entity189 . The cytology was positive in 0 of 1 @entity1185 , 5 of 7 PUNLMP lesions, 18 of 50 @entity189 , and 28 of 37 high-grade @entity189 . In addition, morphologic uniformity and cytoplasmic homogeneity (50.0% and 45.0%, respectively) were seen more commonly in low-grade @entity150 . CONCLUSIONS: The diagnostic accuracy of urine cytology for high-grade lesions decreased, as expected; however, cytologic detection of low-grade @entity189 was remarkably lower than expected. In addition, no outstanding cytologic features could be identified to make a definitive diagnosis.

The effects of the current World Health Organization/International Society of Urologic Pathologists XXXX classification system on urine cytology results.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity4929 :: ('MESH:C565310', 'Disease') :: ['papillary urothelial neoplasms'] @entity1494 :: ('MESH:D001745', 'Disease') :: ['bladder lesions'] @entity5 :: ('MESH:D009369', 'Disease') :: ['urothelial neoplasms', 'tumors'] @entity1185 :: ('MESH:D010212', 'Disease') :: ['papillomas', 'papilloma'] @entity189 :: ('MESH:D002277', 'Disease') :: ['urothelial carcinoma', 'low-grade carcinomas', 'carcinomas', 'carcinoma', 'urothelial carcinomas'] @entity1606 :: ('MESH:D002295', 'Disease') :: ['Grade 1 transitional cell carcinoma', 'TCC'] @entity150 :: ('MESH:D001749', 'Disease') :: ['bladder tumors']
@entity150 :: (MESH:D001749,Disease) :: ['bladder neoplasm']
