Increase in the Rate of HPV Positive Oropharyngeal Cancers During 1996-2011 in a Case Study in Turkey

Abstract

<b>Background:</b> Primary aim of this study is to assess whether or not there is an increase at rate of HPV positiveoropharyngeal cancers during 1996-2011 in Turkey, for comparison with prior reports from Western countries.Materials and <br/><b>Methods</b>: A total of 138 newly diagnosed patients with oropharyngeal cancer were identified, 39 ofwhich had no primary tumor specimen available and 18 patients with invalid HPV status, therefore HPV statusfor remaining 81 patients was evaluated. The presence and type of HPV DNA were determined with formalinfixedparaffin embedded specimens, using an HPV DNA-based multiplex PCR assay. Associations between HPVstatus and clinicopathological characteristics were evaluated using a two-sample t-test for the continuous variablesand the categorical variables were compared by chi-square test. Overall survival (OS) periods were calculatedwith Kaplan-Meier method. <br/><b>Results</b>: The proportion of HPV-positive cancer has continued to increase during2004-2011 as compared with 1996-2003. Notably, 33% (6/18) of the cases were HPV-positive in 1996-1999, 43%(9/21) in 2000-2003, 55% (11/20) in 2004-2007 and 70% (16/23) in 2008-2011. Thus, when we compared the resultsobtained during the 2004-2011with results of 1996-2003 period, we found that increase at HPV-positivity ratiowas statistically significant (38% vs 64% p=0.012). <br/><b>Conclusions</b>: This study demonstrated that HPV positiveoropharyngeal cancers are increasing in Turkish patients as in the Western world.