title: The utility of p16 INK4a and Ki-67 to identify high-grade squamous intraepithelial lesion in adolescents and young women.
abstract: BACKGROUND
  The repair of the immature squamous epithelium following HPV infection may mimic HSIL in adolescent women.
  
  
  OBJECTIVE
  to study the utility of p16 INK4a and Ki-67 in diagnosis of cervical squamous lesions in adolescents and young adults.
  
  
  METHODS
  In a cross-sectional study, the evaluation of p16 INK4a and Ki-67 immunohistochemistry was performed on 72 cervical biopsies of adolescents and young adults women diagnosed as negative for malignancy and intraepithelial lesion (NML) (n = 18) or positive for low grade (LSIL) (n = 31) and high grade (HSIL) (n = 23) squamous intraepithelial lesions in two references services in Fortaleza-Brazil. Data was evaluated using Fisher's test and Kappa index.
  
  
  RESULTS
  p16 INK4a was positive in 81% of HSIL, 19% of LSIL and in no NML (P < 0.0001). Ki-67 was positive in 74%, 32% and 5.5% of HSIL, LSIL and NML, respectively. p16 INK4a and Ki-67 in the diagnosis of HSIL showed high sensitivity and negative predictive value. Kappa index was very good for p16 INK4a (k = 0.72).
  
  
  CONCLUSIONS
  In adolescents and young adults p16 INK4a alone or with Ki-67 represents important tool to reduce mistaken diagnosis of HSIL and to avoid overtreatment.
authors.affiliation: Department of Pathology, Federal University of Ceará, Fortaleza, Brazil.
authors.forename: Diane M
authors.initials: DM
authors.lastname: Cavalcante
authors.forename: Iara M
authors.initials: IM
authors.lastname: Linhares
authors.forename: Margarida M L
authors.initials: MM
authors.lastname: Pompeu
authors.forename: Paulo C
authors.initials: PC
authors.lastname: Giraldo
authors.forename: José
authors.initials: J
authors.lastname: Eleutério
mesh_terms: D000293:Adolescent; D001706:Biopsy; D001938:Brazil; D002584:Cervix Uteri / Q000473:pathology; D003430:Cross-Sectional Studies; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000032:analysis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis*; D018307:Neoplasms, Squamous Cell / Q000175:diagnosis* / Q000473:pathology*; D055815:Young Adult; D002578:Uterine Cervical Dysplasia / Q000175:diagnosis* / Q000473:pathology*
chemical_list: D019941:Cyclin-Dependent Kinase Inhibitor p16; D019394:Ki-67 Antigen