title: Predicting absolute risk of CIN3 during post-colposcopic follow-up: results from the ASCUS-LSIL Triage Study (ALTS).
abstract: OBJECTIVE
  At present, clinical management of women referred to colposcopy but found to have <CIN2 remains unclear. Using data from the ASCUS-LSIL Triage Study (ALTS) to inform clinical management, we calculated the absolute risk for developing CIN3 within 2 years of referral to an enrollment colposcopy.
  
  
  METHODS
  Women included in the analyses: (1) were initially referred to ALTS with a community cytologic interpretation of atypical squamous cell of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesions (LSIL); (2) had a colposcopic evaluation and biopsy, if indicated, resulting in a diagnosis <CIN2; and, therefore (3) were followed without treatment. Results from subsequent human papillomavirus (HPV) testing, liquid-based cytology interpretations, and a second colposcopic evaluation at least 6 months after and within 2 years of the first colposcopic evaluation were used to calculate absolute risks for CIN3.
  
  
  RESULTS
  Women with HPV-negative test results were at low risk for CIN3 regardless of other test results. Among HPV-positive women, increasing absolute risks of CIN3 were observed with increasing cytology severity: 7% (normal), 11% (ASCUS and LSIL), and 45% (HSIL). The highest absolute risk for CIN3 (67%) was observed for HPV-positive women with HSIL and a colposcopic impression of high-grade/cancer on the second colposcopy.
  
  
  CONCLUSIONS
  In the ALTS population, after the first colposcopic diagnosis of <CIN2, clear risk stratification for CIN3 outcomes was obtained among women with a subsequent HPV-positive test. Because absolute risk for histologic CIN3 outcomes was high for women with HPV positive tests, HSIL cytology, and a high-grade impression at second colposcopy, it is worth considering whether this combination of findings might warrant immediate excisional therapy in some circumstances.
authors.affiliation: Department of Obstetrics and Gynecology, University of Oklahoma, Oklahoma City, OK, USA. Joan-walker@ouhsc.edu
authors.forename: Joan L
authors.initials: JL
authors.lastname: Walker
authors.forename: Sophia S
authors.initials: SS
authors.lastname: Wang
authors.forename: Mark
authors.initials: M
authors.lastname: Schiffman
authors.forename: Diane
authors.initials: D
authors.lastname: Solomon
mesh_terms: D000328:Adult; D002278:Carcinoma in Situ / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology / Q000821:virology; D003127:Colposcopy; D004279:DNA, Viral / Q000032:analysis; D004598:Electrosurgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015337:Multicenter Studies as Topic; D027383:Papillomaviridae / Q000302:isolation & purification; D030361:Papillomavirus Infections / Q000453:epidemiology; D017410:Practice Guidelines as Topic; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D014218:Triage; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology / Q000821:virology; D014626:Vaginal Smears
chemical_list: D004279:DNA, Viral