title: Atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion: cytohistologic correlation study with diagnostic pitfalls.
abstract: OBJECTIVE
  In the current study, we explore the diagnostic parameters and pitfalls in the follow-up of 123 cases of Pap smears diagnosed as high-grade atypical squamous cells (ASC-H) at our institution.
  
  
  METHODS
  A computer database search was performed from the archives of the Ottawa Hospital Cytopathology Service for cases diagnosed with ASC-H between January 2003 and July 2005.
  
  
  RESULTS
  Follow-up of the 123 cases of ASC-H showed high grade squamous intraepithelial lesion (HSIL) in 73 patients (59.4%), low grade squamous intraepithelial lesion (LSIL) in 11 (8.9%), immature squamous metaplasia in 23 (18.7%), reactive squamous cell changes in 12 (9.8%), benign glandular lesions (endocervical atypia, degenerated glandular cells) in 2 (1.6%) and atrophy in 2 (1.6%). In our study, 83 patients were younger than 40 years (67.4%), with biopsy-proven HSIL found in 54 patients (65.1%). The remaining 40 patients (32.6%) were older than 40 years of age, and follow-up biopsies showed HSIL in 19 patients (47.5%).
  
  
  CONCLUSIONS
  In our study, 59.4% of the cases that were diagnosed cytologically as ASC-H were found to have HSIL on subsequent biopsies. This correlation was stronger in patients below the age of 40 years (65.1% vs. 47.5%). The cytopathologic feature most strongly associated with HSIL was the presence of coarse nuclear chromatin (84%).
authors.affiliation: Cytopathology Department, Division of Anatomic Pathology, The Ottawa Hospital, Faculty of Medicine, The University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Ghadeer A
authors.initials: GA
authors.lastname: Mokhtar
authors.forename: Nicolas L D Roustan
authors.initials: NL
authors.lastname: Delatour
authors.forename: Ali H
authors.initials: AH
authors.lastname: Assiri
authors.forename: M Angela
authors.initials: MA
authors.lastname: Gilliatt
authors.forename: Mary
authors.initials: M
authors.lastname: Senterman
authors.forename: Shahidul
authors.initials: S
authors.lastname: Islam
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D002466:Cell Nucleolus / Q000473:pathology; D002584:Cervix Uteri / Q000473:pathology*; D002843:Chromatin / Q000473:pathology; D003127:Colposcopy; D003593:Cytoplasm / Q000473:pathology; D003951:Diagnostic Errors / Q000517:prevention & control*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008679:Metaplasia; D008875:Middle Aged; D018307:Neoplasms, Squamous Cell / Q000145:classification / Q000235:genetics / Q000473:pathology*; D009864:Ontario; D065006:Papanicolaou Test; D009626:Terminology as Topic; D002583:Uterine Cervical Neoplasms / Q000145:classification / Q000235:genetics / Q000473:pathology*; D014626:Vaginal Smears; D002578:Uterine Cervical Dysplasia / Q000145:classification / Q000235:genetics / Q000473:pathology*
chemical_list: D002843:Chromatin