title: Performance Characteristics of Urinary Tract Cytology: Observations From the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytopathology.
abstract: BACKGROUND
  Urine cytology is used in the evaluation of hematuria or to follow patients with known urothelial neoplasia.
  
  
  OBJECTIVE
  To investigate the performance characteristics of urinary cytology challenges in the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytopathology.
  
  
  METHODS
  Participant responses from 2000 to 2010 were evaluated for the reference diagnoses of high-grade urothelial carcinoma (HGUC), squamous cell carcinoma, adenocarcinoma, and benign diagnoses (including polyomavirus infection and ileal loop urine). Responses were compared for differences in sample preparation (conventional, liquid based, and cytospin) and participant type (laboratory, pathologist, cytotechnologist).
  
  
  RESULTS
  There were 96 093 responses (46 637 pathologists [48.5%], 29 976 cytotechnologists [31.2%], and 19 480 laboratories [20.3%]); 69 814 of 74 821 responses (93.3%) for the general category positive for malignancy and 18 698 of 21 272 responses (87.9%) for positive for malignancy were concordant. Of the malignant reference diagnoses, 83.3% (59 985 of 71 581), 43.9% (732 of 1667), and 49.1% (370 of 756) were correctly identified as HGUC, adenocarcinoma, and squamous cell carcinoma, respectively. However, 802 of 1669 adenocarcinoma challenges (48.1%) and 275 of 755 squamous cell carcinoma challenges (36.4%) were misdiagnosed as HGUC. For the benign cases, the most common diagnostic pitfall was overinterpretation of ileal loop urines (330 of 5291; 6.2%) and Polyomavirus challenges (220 of 3535; 6.2%) as HGUC. For the general diagnosis of positive for malignancy, cytotechnologists performed slightly better that pathologists (94.5% [23 553 of 24 924] versus 92.3% [36 210 of 39 230]), whereas the reverse occurred for the negative category (85.6% [6423 of 7503] versus 88.8% [10 427 of 11 742]).
  
  
  CONCLUSIONS
  Although the participants performed well in accurately classifying cases as benign and malignant, there were difficulties with the correct identification of adenocarcinoma and squamous cell carcinoma cases and with overinterpretation of ileal loop and Polyomavirus challenges as HGUC.
authors.forename: Güliz A
authors.initials: GA
authors.lastname: Barkan
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Laucirica
authors.forename: Manon
authors.initials: M
authors.lastname: Auger
authors.forename: Walid
authors.initials: W
authors.lastname: Khalbuss
authors.forename: Vijyalakshmi
authors.initials: V
authors.lastname: Padmanabhan
authors.forename: Rhona
authors.initials: R
authors.lastname: Souers
authors.affiliation: From the Department of Pathology, Loyola University Medical Center, Maywood, Illinois (Dr Barkan); the Department of Pathology and Laboratory Medicine, University of Texas Medical School, Houston (Dr Laucirica); the Department of Pathology & Immunology, Baylor College of Medicine, Houston (Dr Laucirica); the Department of Pathology, McGill University, Montreal, Quebec, Canada (Dr Auger); the Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania (Dr Khalbuss); the Department of Pathology, Geisel School of Medicine, Hanover, New Hampshire (Dr Padmanabhan); the Department of Pathology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (Dr Padmanabhan); the Biostatistics Department, College of American Pathologists, Northfield, Illinois (Ms Souers); the Department of Anatomic and Clinical Pathology, AmeriPath, Indiana, Indianapolis (Dr Moriarty); and GE Clarient Diagnostic Services, Riyadh, Riyadh Province, Saudi Arabia (Dr Khalbuss).
authors.forename: Ann T
authors.initials: AT
authors.lastname: Moriarty
mesh_terms: D003581:Cytodiagnosis / Q000592:standards*; D006801:Humans; D015588:Observer Variation; D010338:Pathology, Clinical / Q000592:standards*; D016482:Urinalysis / Q000592:standards*; D014570:Urologic Diseases / Q000175:diagnosis*