title: Use of combined molecular biomarkers for prediction of clinical outcomes in locally advanced tonsillar cancers treated with chemoradiotherapy alone.
abstract: BACKGROUND
  Environmental exposures to tobacco, alcohol, human papillomavirus (HPV) and/or Epstein-Barr virus (EBV), all of which can perturb multiple cell cycle proteins or tumor suppressors, have been implicated in the pathogenesis of different subsets of head and neck cancers. The aim of this study was to investigate to which extent the virus infection by itself, and/or the altered cell cycle proteins, contributes to prognosis in locally advanced tonsillar squamous cell carcinomas (TSCCs) treated with concurrent chemoradiotherapy (CCRT) alone.
  
  
  METHODS
  Serial tumor tissue arrays from archival samples were tested for the presence of HPV genome integration or EBV episome by means of DNA sequencing, real-time polymerase chain reaction (PCR), and in situ hybridization. Alterations of cell cycle proteins (p53, pRb, and p21) were evaluated by immunohistochemical staining. The association of viral presence with altered cell cycle proteins was correlated to clinical outcomes.
  
  
  RESULTS
  Of the 46 patients with the same T2N2bM0 stage IVA among consecutive patients with TSCC, 23 (50%) had integrated HPV DNA and only 1 (2%) had EBV episome. The HPV types detected were almost all HPV-16. A reduced expression pattern of p53, pRb, and p21 was noted in HPV-positive tumors, and the incremental number of alterations in the 3 proteins was significantly associated with HPV-negative tumors. The presence or absence of HPV together with the number of altered expression of the 3 cell cycle markers resulted in further identification of 4 biologically and clinically distinct subgroups with different outcomes after CCRT.
  
  
  CONCLUSIONS
  Use of combined biomarkers of oncogenic HPV and tumor suppressors of p53, pRb, and p21 in advanced TSCC provides prognostic molecular classification superior to the TNM stage system and identifies low-risk patients for organ preservation by CCRT alone and high-risk patients who might benefit from planned tonsillectomy and neck dissection before or after CCRT.
authors.affiliation: Department of Radiation Oncology, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan. ylchung@mail.kfcc.org.tw
authors.forename: Yih-Lin
authors.initials: YL
authors.lastname: Chung
authors.forename: Ming-Yuan
authors.initials: MY
authors.lastname: Lee
authors.forename: Cheng-Fang
authors.initials: CF
authors.lastname: Horng
authors.forename: James Jer-Ming
authors.initials: JJ
authors.lastname: Jian
authors.forename: Skye Hongiun
authors.initials: SH
authors.lastname: Cheng
authors.forename: Stella Y
authors.initials: SY
authors.lastname: Tsai
authors.forename: Cheng-I
authors.initials: CI
authors.lastname: Hsieh
authors.forename: Lawrence K
authors.initials: LK
authors.lastname: Yen
authors.forename: Ching-Yuan
authors.initials: CY
authors.lastname: Lin