>> P-571: Human papillomavirus 16/18 prevalence in oropharyngeal and oral cavity cancers from 5 US cancer registries
19:00 PM - 19:00 PM
1Centers for Disease Control and Prevention, Atlanta, GA, USA; 2Battelle, Charlotte, NC, USA; 3Louisiana State University Health Science Center School of Public Health, New Orleans LA, USA; 4Michigan Department of Community Health, Lansing, MI, USA; 5University of Hawaii, Honolulu, FL, USA; 6University of Kentucky, Lexington, KY, USA; 7University of Miami School of Medicine, Miami, FL, USA.
Background: The incidence of oropharyngeal and oral cavity (OP/OC) cancers has been increasing among blacks and among men. HPV may play an important role in the current disparities seen in oropharyngeal and oral cavity cancers (OP/OC). As HPV vaccines become widely available, rates of certain OP/OC cancers may decrease.
Objective: To determine baseline HPV distribution of OP/OC cancers (tongue, tonsil, and oropharynx) by racial/ethnic groups (White, Black, Hispanic, Asian) and gender.
Methods: We used 5 state central cancer registries (Michigan, Louisiana, Hawaii, Florida, and Kentucky) to identify all cases of invasive OC/OP cancers diagnosed in 2000-2005. Archived tumor tissue was retrieved from a representative sample of eligible cases, and one diagnostic block per case was serially sectioned for DNA extraction with H&E confirmation of histology in sections immediately preceding and following. All samples were tested using the Linear Array HPV Genotyping Test (Roche Diagnostics), and those negative for HPV or failing to amplify endogenous control were re-tested with INNO-LiPA HPV Genotyping Assay (Innogenetics). Samples failing to amplify control sequences in both assays were considered inadequate and excluded from analysis.
Results: HPV was detected in 77.4 % (HPV 16/18: 64.7%) of the 190 OP/OC cancers that were available for genotyping. HPV positivity was 80.9% among whites (n=152, [HPV 16/18:69.1%]); 87.5% among Hispanics [n=8, HPV 16/18: 87.5%]); and 50% among blacks (n=18 [HPV 16/18:16.7%]), and 60% among Asians (n=10, HPV16/18: 60%). Of the 142 cancers that were diagnosed among males, HPV positivity rate was 80.3% (HPV 16/18: 69.7%). HPV positivity was 68.8% among females (n=48; HPV 16/18: 50%).
Conclusion: Overall HPV positivity and HPV 16/18 prevalence varied by race/ethnicity and gender. Establishing this baseline distribution will be helpful in monitoring the impact of the HPV16/18 vaccine, especially if vaccine coverage differs by race or gender.