title: Cell Block Preparation versus Liquid-Based Thin-Layer Cervical Cytology: A Comparative Study Evaluating Human Papillomavirus Testing by Hybrid Capture-2/Cervista, in situ Hybridization and p16 Immunohistochemistry.
abstract: OBJECTIVE
  Cell block (CB) preparations from residual liquid-based Pap samples have been shown to be of diagnostic value. In this study we evaluated human papillomavirus (HPV) in situ hybridization (ISH) and p16 immunohistochemistry (IHC) on CB preparations and compared the results with the primary diagnosis and standard HPV tests.
  
  
  METHODS
  In total, 197 HE-stained CB slides prepared from CBs from residual Pap samples (152 ASCUS, 2 ASC-H, 32 LGSIL, 4 HGSIL, 1 AGUS and 6 normal) were analyzed. Hybrid Capture-2 (HC-2)/Cervista testing and HPV ISH and p16 IHC were performed on the CB samples. The test performance characteristics were compared with HPV and p16 assay performances.
  
  
  RESULTS
  The cellular architecture was well maintained in CBs with excellent consistency. HPV ISH testing had an excellent concordance with the HC-2/Cervista methods (85%) with high sensitivity (82.6%; 95% CI 75.9, 89.4) and specificity (89.3%). Of all the p16 tests, 38% were positive (60 out of 159 samples). The overall concordance between p16 and HC-2/Cervista (64%), or between p16 and ISH (68%), was lower than the concordance between ISH and HC-2/Cervista (85%).
  
  
  CONCLUSIONS
  HPV ISH and p16 IHC testing is feasible, cost effective and practical. A combination of the two tests would ultimately improve diagnostic accuracy, leading to better therapeutic decisions.
authors.affiliation: Department of Pathology and Laboratory Medicine, Kansas University Medical Center, Kansas City, Kans., USA.
authors.forename: Ossama
authors.initials: O
authors.lastname: Tawfik
authors.forename: Marilyn
authors.initials: M
authors.lastname: Davis
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Diaz
authors.forename: Fang
authors.initials: F
authors.lastname: Fan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002584:Cervix Uteri / Q000473:pathology* / Q000821:virology*; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D017403:In Situ Hybridization / Q000379:methods*; D008875:Middle Aged; D065006:Papanicolaou Test / Q000379:methods; D027383:Papillomaviridae / Q000235:genetics*; D030361:Papillomavirus Infections / Q000175:diagnosis / Q000473:pathology / Q000821:virology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014626:Vaginal Smears / Q000379:methods; D055815:Young Adult
chemical_list: D019941:Cyclin-Dependent Kinase Inhibitor p16