title: Factors influencing histologic confirmation of high-grade squamous intraepithelial lesion cytology.
abstract: OBJECTIVE
  To examine the predictors of histologic confirmation of high-grade squamous intraepithelial lesion (HSIL) cytology occurring in follow-up of young women originally referred into a trial because of less severe cytology.
  
  
  METHODS
  We used enrollment HSIL cytology (N=411) as read by clinical center pathologists for women participating in the ASCUS-LSIL Triage Study (ALTS). The primary outcome was histologic cervical intraepithelial neoplasia (CIN) grade 3 and early cancer (n=195; 191 CIN 3 and four cancers) as diagnosed by the Pathology Quality Control Group during the 2-year duration of ALTS.
  
  
  RESULTS
  The 2-year absolute risk of CIN 3 or worse after an HSIL cytology was 47.4% (95% confidence interval 42.5-52.4%). The 2-year absolute risk of CIN 3 or worse was lowest (14.3%) for women who were human papillomavirus (HPV)-16-negative, had colposcopic impression of less than low-grade, and whose HSIL cytology as called by the clinical center was not also called HSIL or equivocal HSIL cytology by the Pathology Quality Control Group. The 2-year absolute risk of CIN 3 or worse was highest (82.4%) for women who were HPV16-positive, had colposcopic impression of low-grade or worse, and whose HSIL cytology also was called HSIL or equivocal HSIL cytology by the Pathology Quality Control Group.
  
  
  CONCLUSIONS
  Histologic confirmation of precancer among young women with HSIL cytology was more likely when other risk factors (eg, HPV16) for cervical precancer were present.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland, USA. castlep@mail.nih.gov
authors.forename: Philip E
authors.initials: PE
authors.lastname: Castle
authors.forename: J Thomas
authors.initials: JT
authors.lastname: Cox
authors.forename: Mark
authors.initials: M
authors.lastname: Schiffman
authors.forename: Cosette M
authors.initials: CM
authors.lastname: Wheeler
authors.forename: Diane
authors.initials: D
authors.lastname: Solomon