The median age at which human papilloma virus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) is diagnosed is increasing, according to a study published in Cancer.
Contrary to previously held wisdom that HPV-OPSCC is a disease typically associated with younger age groups, a recent study has shown that the incidence of OPSCC — possibly driven by HPV — is increasing among older patients.
For this retrospective study, researchers analyzed the cases of 239 patients with OPSCC diagnosed between 1995 and 2013, and performed p16 immunohistochemistry and in situ hybridization (ISH) for HPV-16, high-risk DNA, and/or E6/E7 RNA; p16 expression is strongly associated with HPV infection. Investigators then examined the association between tumor status and age at diagnosis.
Of 239 patients, 60% (144) were p16-positive. Analysis revealed that the median age among patients who were p16 positive increased from 53 years to 58 years between 1998 and 2013, but not among patients who were p16-negative.
The proportion of OPSCC that were p16-positive increased among patients who were older than 65 years from 41% to 75% during 1995-2000 and 2007-2013, respectively.
Further analysis showed that p16-positive tumor status improved overall survival outcomes compared with p16-negative tumor status, confirming a previously established prognostic marker for survival.
Results of the study demonstrate that the recent increased incidence of OPSCC among older patients is associated with the increased rate of HPV, the median age of HPV-OPSCC diagnosis has increased, and HPV-positive tumor status confers a survival benefit.
Windon MJ, D’Souza G, Rettig EM, et al. Increasing prevalence of human papillomavirus-positive oropharyngeal cancers among older adults [published online April 30, 2018]. Cancer. doi: 10.1002/cncr.31385