title: Human papillomavirus prevalence and cell cycle related protein expression in tonsillar squamous cell carcinomas of korean patients with clinicopathologic analysis.
abstract: BACKGROUND
  Human papillomavirus (HPV)-related tonsillar squamous cell carcinoma (TSCC) has recently been characterized as a distinct subset with a favorable prognosis. The prevalence and clinicopathologic significance of HPV-related TSCC in Koreans are not well known.
  
  
  METHODS
  HPV in situ hybridization (ISH) accompanied by p53, p16, pRb, and cyclin D1 immunohistochemical staining were performed on 89 resection cases of TSCC from 2000 through 2010.
  
  
  RESULTS
  HPV was detected by ISH in 59 of 89 cases (66.3%). HPV-positive TSCCs were more common in younger ages (p=0.005), and tumor sizes were smaller in the HPV-positive compared to the HPV-negative group (p=0.040). Positive HPV staining was significantly correlated with p16 expression (p<0.001), pRb inactivation (p=0.003), and cyclin D1 down-regulation (p<0.001) but not with p53 expression (p=0.334). Seventeen cases that showed p16-immunopositivity with HPV-negativity by ISH were retested by HPV typing; HPV DNA was not detected in all cases. There was no significant difference between HPV-positive and HPV-negative patients either in the disease-specific survival (DSS, p=0.857) or overall survival (p=0.910). Furthermore, pRb-inactivated cases showed better DSS (p=0.023), and p53-positive cases showed worse DSS (p=0.001).
  
  
  CONCLUSIONS
  Although high HPV prevalence was noted, it was not correlated with histopathologic findings or survival benefit. In addition to p53 expression, pRb inactivation along with p16 overexpression and down-regulation of cyclin D1 are thought to be important pathogenetic steps for developing TSCCs.
authors.affiliation: Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Miji
authors.initials: M
authors.lastname: Lee
authors.forename: Sung Bae
authors.initials: SB
authors.lastname: Kim
authors.forename: Sang-Wook
authors.initials: SW
authors.lastname: Lee
authors.forename: Jong-Lyel
authors.initials: JL
authors.lastname: Roh
authors.forename: Seung-Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Soon Yuhl
authors.initials: SY
authors.lastname: Nam
authors.forename: Sang Yoon
authors.initials: SY
authors.lastname: Kim
authors.forename: Kyung-Ja
authors.initials: KJ
authors.lastname: Cho
keywords: Carcinoma, squamous cell; Cyclin-dependent kinase inhibitor p16; Human papillomavirus; Tonsillar neoplasm; Tumor suppressor protein p53