title: Improved survival of Japanese patients with human papillomavirus-positive oropharyngeal squamous cell carcinoma.
abstract: BACKGROUND
  The prevalence of oropharyngeal carcinoma is rising in western Europe and the United States, where there appears to be a strong association between human papillomavirus (HPV) and oropharyngeal squamous cell carcinoma (OPSCC). However, such a correlation has not yet been fully evaluated in Japan.
  
  
  METHODS
  We performed a retrospective analysis of the association between tumour HPV status and the demographic and clinicopathological parameters of 71 patients with OPSCC at Hokkaido University Hospital, Japan, between 1998 and 2009. The parameters included age, gender, survival, tumour subsite, tumour-node-metastasis (TNM) stage, smoking history, second primary tumour status, recurrence/residual disease at the primary site, and overall survival. HPV status was established by multiplex polymerase chain reaction (PCR) analysis.
  
  
  RESULTS
  Of the 71 oropharyngeal cancers, 20 were positive for HPV-16, two for HPV-18, and one for HPV-58. Kaplan-Meier survival analysis showed improved overall survival rates in patients with HPV-positive tumours (p = 0.0038) compared with HPV-negative tumours. Of the 45 patients who received chemoradiotherapy, HPV-positive patients experienced better overall survival than HPV-negative patients (p = 0.0032). In a multivariate analysis, the survival benefit of HPV-positive patients was independent of age and T and N classification.
  
  
  CONCLUSIONS
  HPV status is a significantly favourable prognostic factor in oropharyngeal cancer and could be used as a marker to optimize the treatment of patients with this type of cancer in Japan.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, 060-8638, Japan, mizumati@med.hokudai.ac.jp.
authors.forename: Takatsugu
authors.initials: T
authors.lastname: Mizumachi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kano
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Sakashita
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Hatakeyama
authors.forename: Seigo
authors.initials: S
authors.lastname: Suzuki
authors.forename: Akihiro
authors.initials: A
authors.lastname: Homma
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Oridate
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fukuda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000473:pathology* / Q000628:therapy / Q000821:virology; D005260:Female; D052162:Human papillomavirus 16 / Q000472:pathogenicity; D052161:Human papillomavirus 18 / Q000472:pathogenicity; D006801:Humans; D007564:Japan; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology* / Q000628:therapy / Q000821:virology; D009959:Oropharyngeal Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy / Q000821:virology; D030361:Papillomavirus Infections / Q000401:mortality / Q000473:pathology* / Q000628:therapy / Q000821:virology; D011379:Prognosis; D012189:Retrospective Studies