title: The role of p16 expression as a predictive marker in HPV-positive oral SCCHN--a retrospective single-center study.
abstract: Squamous cell carcinoma of the head and neck (SCCHN) is the sixth most common type of cancer worldwide; 600,000 new cases are diagnosed every year. Infected with high-risk human papilloma virus (HPV) types are particularly linked to oropharyngeal cancer. Among over 100 different HPV types, HPV-16 and HPV-18 are detected in the majority of HPV-positive SCCHNs. The p16 gene is often mutated in SCCHN, its overexpression is caused by the viral E7 protein. Consequently, p16 is assumed to be an indirect marker of HPV-induced SCCHN. The aim of the present study was to determine the role of p16 expression as a predictive marker of HPV infection in SCCHN tumors in a retrospective single-center study.
  
  
  METHODS
  Oropharyngeal tumor samples from 45 patients (34 males, 11 females) were analyzed. Tumor samples were examined for HPV infection using a two-step PCR. p16 staining by immunohistochemistry was then performed.
  
  
  RESULTS
  Samples with strong p16 signal were typed HPV-16-positive. Out of 14 tumor samples with HPV-positive PCR results, 13 samples contained the high risk variant HPV-16. In one sample, HPV-6 DNA was detected. All HPV-16-positive tumors overexpressed p16 (p16(+++)), whereas the HPV-6 sample was p16-negative.
  
  
  CONCLUSIONS
  p16 is not a surrogate marker for replacing PCR testing, but both methods in combination, PCR and immunohistochemistry, could lead to a higher diagnostic validation.
authors.affiliation: ENT Department, University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt/Main, Germany.
authors.forename: Christin
authors.initials: C
authors.lastname: Geißler
authors.forename: Aykut
authors.initials: A
authors.lastname: Tahtali
authors.forename: Marc
authors.initials: M
authors.lastname: Diensthuber
authors.forename: Davina
authors.initials: D
authors.lastname: Gassner
authors.forename: Timo
authors.initials: T
authors.lastname: Stöver
authors.forename: Jens
authors.initials: J
authors.lastname: Wagenblast
mesh_terms: D015415:Biomarkers; D002294:Carcinoma, Squamous Cell / Q000821:virology*; D019941:Cyclin-Dependent Kinase Inhibitor p16; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D006258:Head and Neck Neoplasms / Q000821:virology*; D006801:Humans; D008297:Male; D009062:Mouth Neoplasms / Q000821:virology*; D009363:Neoplasm Proteins / Q000032:analysis* / Q000502:physiology; D027383:Papillomaviridae / Q000302:isolation & purification*; D012189:Retrospective Studies; D000077195:Squamous Cell Carcinoma of Head and Neck
chemical_list: D015415:Biomarkers; C000614131:CDKN2A protein, human; D019941:Cyclin-Dependent Kinase Inhibitor p16; D004279:DNA, Viral; D009363:Neoplasm Proteins