title: Do liquid-based preparations of pulmonary bronchial brushing specimens perform differently from classically prepared cases for the diagnosis of malignancies? Observations from the College of American Pathologists interlaboratory comparison program in nongynecologic cytology.
abstract: BACKGROUND
  Pulmonary bronchial brushing specimens can be processed by liquid-based or conventional methods. The ability to accurately diagnose a pulmonary malignancy with a liquid-based preparation (LBP) versus a conventional preparation may differ.
  
  
  OBJECTIVE
  To compare the performance of LBPs of malignant pulmonary bronchial brushing specimens with the performance of conventional preparations.
  
  
  METHODS
  Participant responses from 553 malignant pulmonary bronchial brushing samples were evaluated for concordance with the general diagnosis. The performance of LBPs was compared with that of classic preparations. A nonlinear mixed model was used to analyze the performance by reference diagnosis, preparation type, program years, participant type, and the interaction terms between these 4 factors.
  
  
  RESULTS
  Concordance with the general category of malignant disease was observed in 95.2% of conventional Papanicolaou-stained, 90.9% of modified Giemsa-stained, and 96.9% of LBP (P < .001) samples. The results were significantly different between individual reference diagnoses (P < .001). The performance of LBPs was consistently higher for most diagnoses and was significantly better for squamous cell carcinoma (P = .005), small cell carcinoma (P < .001), and metastatic carcinoma not otherwise specified (P < .001). All participant types performed significantly better with LBPs of small cell carcinoma. Pathologists and cytotechnologists performed significantly better with LBPs of squamous cell carcinoma. A significantly higher concordance was observed between the general diagnosis and program years 2007-2011 versus 2001-2006 (P = .006).
  
  
  CONCLUSIONS
  Liquid-based preparations performed better than conventional methods, with significantly higher performance in squamous cell, small cell, and metastatic carcinomas. Improved performance over time may reflect more frequent use of LBP methods and increased familiarity with interpreting the morphologic findings.
authors.affiliation: From the Department of Pathology, University of California, San Francisco (Dr Tabatabai); the Department of Pathology, McGill University Health Center, Montreal, Quebec, Canada (Dr Auger); the Department of Pathology, Wisconsin State Lab of Hygiene, Madison (Dr Kurtycz); the Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas (Dr Laucirica); the Department of Biostatistics, College of American Pathologists, Northfield (Ms Souers), and the Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago (Dr Nayar), Illinois; the Department of Pathology, University of Pittsburgh Medical Center-Shadyside, Pittsburgh, Pennsylvania (Dr Khalbuss); the Department of Pathology, AmeriPath Indiana, Indianapolis (Dr Moriarty); and the Department of Pathology and Laboratory Medicine, University of Louisville School of Medicine, Louisville, Kentucky (Dr Fraig).
authors.forename: Z Laura
authors.initials: ZL
authors.lastname: Tabatabai
authors.forename: Manon
authors.initials: M
authors.lastname: Auger
authors.forename: Daniel F I
authors.initials: DF
authors.lastname: Kurtycz
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Laucirica
authors.forename: Rhona J
authors.initials: RJ
authors.lastname: Souers
authors.forename: Ritu
authors.initials: R
authors.lastname: Nayar
authors.forename: Walid E
authors.initials: WE
authors.lastname: Khalbuss
authors.forename: Ann T
authors.initials: AT
authors.lastname: Moriarty
authors.forename: Mostafa
authors.initials: M
authors.lastname: Fraig
mesh_terms: D001706:Biopsy; D001980:Bronchi / Q000473:pathology*; D001999:Bronchoscopy; D003581:Cytodiagnosis; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000473:pathology; D017711:Nonlinear Dynamics; D010338:Pathology, Clinical / Q000379:methods*; D012955:Societies, Medical; D013048:Specimen Handling / Q000379:methods*; D014481:United States