Oral Human Papillomavirus (HPV) Infection among Unvaccinated High-Risk Young Adults

Natural History of Oral HPV Infection among Indigenous South Australians

This study aims to describe the natural history of and identify the risk factors associated with oral human papillomavirus (HPV) infections in an Australian Indigenous cohort. A longitudinal cohort study design, with baseline (2018), 12-month, and 24-month data obtained from Indigenous Australians aged 18+ years in South Australia, was performed. Face-to-face interviews were conducted, and saliva samples for HPV testing were collected at each time point. Basic descriptive analyses were conducted to calculate prevalence, incidence, persistence, clearance, and incidence proportions of any HPV infection. Multivariable logistic regression analyses with adjusted prevalence ratios (PRs) were conducted to identify risk factors associated with oral HPV infection. Among 993 participants with valid saliva samples, 44 HPV types were identified. The prevalence of infection with any oral HPV infection was 51.3%, high-risk HPV was 11%, and types implicated in Heck's disease (HPV 13 or 32) was 37.4%. The incidence, persistence, and clearance of any and high-risk HPV infections were 30.7%, 11.8% and 33.3% vs. 9.3%, 2.8%, and 9%, respectively. Our findings indicate that the prevalence, incidence, and persistence of oral HPV infection in a large sample of Indigenous Australians were high, and clearance was low. Oral sex behaviours and recreational drug use were risk factors associated with incident high-risk HPV infection.

Relationship Between Sexual Orientation and Human Papillomavirus-Related Oral Cancer Knowledge and Awareness

Purpose: Human papillomavirus (HPV)-related oral cancers are increasing, and lesbian, gay, bisexual, and other people with a minority sexual orientation may be disproportionately impacted. This study examined the relationship between sexual orientation and HPV-related oral cancer knowledge. Methods: Data from 10,859 adult participants in the 2017-2019 Health Information National Trends Survey 5, cycles 1-3, were obtained. The three data sets were merged, and weighted multiple imputation (n = 15) was applied to address missingness. Weighted logistic regression analyses examined differences in HPV-related oral cancer knowledge between sexual minority versus heterosexual participants by sex, after adjustment for race, ethnicity, age, education, income, insurance, regular medical provider, and smoking status. Results: In this weighted sample, age ranged from 18 to 101 years (mean = 56.3 years); 42% were males, 5.2% were sexual minority men/women, and 94.8% were heterosexual/straight. Overall, only 19% of respondents were aware that HPV can cause oral cancer. After controlling for sociodemographic factors, there were no significant differences in HPV-related oral cancer knowledge for sexual minority men (adjusted odds ratio [AOR]: 1.10; 95% confidence interval [95% CI]: 0.86-1.42) or women (AOR: 0.98; 95% CI: 0.76-1.26) compared with those who were heterosexual/straight. Conclusion: Overall, knowledge of HPV-related oral cancer was low, regardless of sexual orientation. There were no differences in HPV-related oral cancer knowledge between sexual minority men and women compared with their heterosexual counterparts. Educational programs are needed to increase awareness of the HPV/oral cancer link. Further research on differences in HPV-related oral cancer knowledge and attitudes by sexual orientation and the intersection of other demographic factors is warranted.

Oral human papillomavirus prevalence, persistence, and risk-factors in HIV-positive and HIV-negative adults

Background

HIV has been shown to increase the likelihood of oral HPV infection. In this study, we evaluated the risk of oral HPV in HIV infected patients compared with HIV-negative controls.

Methods

101 healthy adult volunteers (HIV-) and 245 adults living with HIV infection (HIV+) were recruited from 5 academic medical centers. Questionnaires and saliva samples were obtained every 3–8 months over a period of 2 years (2015–2017). DNA was isolated from the saliva samples and tested for 18 high- and low-risk genotypes.

Results

Oral HPV was detected in 23% of HIV + vs. 10% of HIV- participants (p < 0.0001). Men had a higher oral HPV prevalence than women (27% vs. 15% HIV+, p = 0.03, 16% vs. 5% HIV-, p = 0.01). Risk factors among HIV + participants included more lifetime deep kissing and oral sex partners, and history of AIDS. Persistent oral HPV was detected in 23% of HIV + vs. 5% of HIV- participants (p < 0.001). Among 8 HIV + participants with CD4 counts <200 cell/μL none had cleared their HPV infection during the study.

Conclusions

Risk of oral HPV infection and persistence was significantly higher in HIV + adults with a history of poorly controlled HIV, which may put them at increased risk of HPV-associated cancer.

The Effect of Prophylactic HPV Vaccines on Oral and Oropharyngeal HPV Infection-A Systematic Review

Human papillomavirus (HPV) imposes an increased risk of developing cervical, anal and oropharyngeal cancer. In the Western world, HPV infection is currently the major cause of oropharyngeal cancer. The effectiveness of HPV vaccines for oral or oropharyngeal HPV infection is yet to be determined. This study conducted a systematic literature search in Pubmed and Embase. Studies investigating the impact of HPV vaccines on oral or oropharyngeal HPV infection were enrolled. This review reports the relative prevention percentage (RPP), including a risk of bias assessment as well as a quality assessment study. Nine studies were included (48,777 participants): five cross-sectional studies; one randomized community trial study (RCT); one longitudinal cohort study; and two case-control studies. A significant mean RPP of 83.9% (66.6–97.8%) was calculated from the cross-sectional studies, 82.4% in the included RCT and 83% in the longitudinal cohort study. Further, two case-control studies that measured antibody response in participants immunized with HPV vaccines were included. Respectively, 100% and 93.2% of participants developed HPV-16 Immunoglobulin G (IgG) antibodies in oral fluids post-vaccination. Analysis of the studies identified a significant decrease in vaccine-type oral or oropharyngeal HPV infections in study participants immunized with HPV vaccines across study designs and heterogenous populations. Further, a significant percentage of participants developed IgG antibodies in oral fluid post-vaccination.

Oral Human Papillomavirus Infection in Children during the First 6 Years of Life, Finland

Human papillomavirus (HPV) infections are found in children, but transmission modes and outcomes are incompletely understood. We evaluated oral samples from 331 children in Finland who participated in the Finnish Family HPV Study from birth during 9 follow-up visits (mean time 51.9 months). We tested samples for 24 HPV genotypes. Oral HPV prevalence for children varied from 8.7% (at a 36-month visit) to 22.8% (at birth), and 18 HPV genotypes were identified. HPV16 was the most prevalent type to persist, followed by HPV18, HPV33, and HPV6. Persistent, oral, high-risk HPV infection for children was associated with oral HPV carriage of the mother at birth and seroconversion of the mother to high-risk HPV during follow-up (odds ratio 1.60–1.92, 95% CI 1.02–2.74). Children acquire their first oral HPV infection at an early age. The HPV status of the mother has a major impact on the outcome of oral HPV persistence for her offspring.

Prevalence of oral human papillomavirus infection among university students in Valencia, Spain

Human papillomavirus (HPV) infection contributes to the pathogenesis of oropharyngeal squamous cell carcinomas. We estimated prevalence and six-month persistence of oral HPV infections among university students ages 18-25 years living in Valencia, Spain, during the 2012-2013 academic year. Participants provided oral rinse samples; HPV-positive subjects provided a follow-up sample. The study included 543 students; 70 (12.9%) women had received HPV vaccination. Prevalence among vaccinees and non-vaccinees were 10.0% (95% CI: 4.1-19.5%) and 6.8% (95% CI: 4.7-9.4%), respectively. All HPV infections among vaccinees were non-typeable genotypes; 59.4% of non-vaccinees had high-risk genotype infections. Follow-up samples were obtained from 36 participants; one vaccinee (whose specimen was non-typeable) and seven non-vaccinees were found to be HPV positive. Among non-vaccinees, six-month persistence was 10.3% (95% CI: 2.2-27.4%); all persistent infections were with high-risk genotypes. Our results, although subject to study limitations, may support the need to implement new public health strategies.

Risk of Oral Human Papillomavirus Infection Among Sexually Active Female Adolescents Receiving the Quadrivalent Vaccine

Importance

Human papillomavirus (HPV) is the most common sexually transmitted infection in the United States, and oral HPV infection is associated with increased risk of oropharyngeal cancer.

Objective

To describe the risk factors for oral HPV in sexually active female adolescents receiving the quadrivalent vaccine.

Design, Setting, and Participants

Longitudinal cohort study involving repeated collection of oral rinse specimens from sexually active female adolescents conducted between October 19, 2007, and March 9, 2017, at a large adolescent health center in New York, New York, that provides free health care, including HPV vaccination.

Exposures

Human papillomavirus vaccination and self-reported history of sexual behavior.

Main Outcomes and Measures

Prevalence of HPV in the oral cavity.

Results

Among the 1259 participants who were included in this study, median age at entry into the study was 18 (range, 13-21) years; 638 (50.7%) were of African American descent, 569 (45.2%) were of Hispanic descent, 43 (3.4%) reported another race/ethnicity, and race/ethnicity was unspecified for 9 (0.7%). The median (mode) age at first sexual activity was 14.8 (14) years, and 1161 (92.2%) reported having had oral sex. Human papillomavirus DNA was detected in baseline oral rinse samples of 78 of the 1259 participants (6.2%; 95% CI, 4.9%-7.6%). There was a significant decrease in oral HPV detection with time (in years) since first engaging in sexual activities, independent of age and concurrent detection of cervical HPV; comparing 4 or more years with 1 year or less, the odds ratio was 0.45 (95% CI, 0.21-0.96). Detection of vaccine types (HPV-6, HPV-11, HPV-16, and HPV-18) was significantly lower among participants who had received at least 1 dose of the quadrivalent HPV vaccine at the time of enrollment compared with those who were unvaccinated (odds ratio, 0.20; 95% CI, 0.04-0.998).

Conclusions and Relevance

This study's findings suggest that detection of HPV in the oral cavity is not uncommon in sexually active female adolescents. In addition, HPV vaccination is associated with a significant decrease in detection of HPV vaccine types in the oral cavity.

Low concordance of oral and genital HPV infection among male patients with sexually transmitted infections in Vietnam

Background

Human papillomavirus (HPV) causes cancers in men, including penile, anal, and oropharyngeal cancers. This cross-sectional study aimed to investigate the prevalence, the genotypes, and the risk factors of HPV infections in the oral cavity, compared to those in the genitals, among males diagnosed with sexually transmitted infections (STIs) in Vietnam.

Methods

Oral, urinary, penile, and urethral samples were collected from 198 male Vietnamese patients with STIs (median age 31.0 years, range 17–68). HPV DNA was isolated and amplified with PCR, with modified and/or original GP5⁺/GP6⁺ primers. Samples were genotyped with a gene array assay and/or population sequencing.

Results

HPV DNA was detected in 69 (34.8%) of 198 patients. Of these, 16 patients (8.1%) had infections in the oral cavity and 58 (29.3%) had infections in the genitals (4.5% in the urine, 25.8% in the penis, and 8.1% in the urethra). The concordance of HPV infections between the oral cavity and the genitals was poor (kappa = 0.01). Of the 16 patients with oral HPV DNA, 11 (68.8%) had no HPV DNA in the genitals. In the remaining five patients, HPV DNA was found at both sites, but only one showed similar strains at both sites. In the other four patients, the HPV genotypes were completely discordant between these sites. HPV18 was the most common high-risk HPV genotype in both oral (9/16, 56.3%) and genital (10/58, 17.2%) sites. Multivariable analyses showed that older age (OR 1.05), higher education (OR 2.17), and no knowledge of STIs (OR 4.21) were independent risk factors for genital HPV infections; in contrast, only older age (OR 1.05) was an independent risk factor for oral HPV infections.

Conclusions

The low concordance of HPV genotypes between oral and genital infection sites suggested that the acquisition, persistence, and/or clearance of HPV infections were different between these sites. Although HPV DNA was detected significantly less frequently in oral samples than in genital samples, oral samples should also be used for HPV screening in men.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4175-0) contains supplementary material, which is available to authorized users.

HPV-16 in a distinct subset of oral epithelial dysplasia

Human papillomavirus (HPV) 16 is the most common high-risk HPV type identified in oropharyngeal and cervical neoplasia. Recently, HPV-associated oral epithelial dysplasia with specific histopathologic features and demographics similar to HPV-oropharyngeal carcinoma has been identified. The objective of this study was to evaluate histopathologically all cases of HPV-oral epithelial dysplasia seen in one center and identify HPV types in a subset of cases. Cases with specific histopathology for HPV-oral epithelial dysplasia that were positive both by immunohistochemical studies for p16 and by in situ hybridization for high-risk types of HPV were further analyzed using QIAamp DNA Tissue Kits (Qiagen, Hilden, Germany). DNA was extracted, amplified, and digested with restriction enzymes and run on a polyacrylamide gel. Digestion patterns were visually compared with a database of known HPV digestion patterns for identification. There were 53 specimens included in the analysis. There were 47 males and six females (7.8:1), with a median age of 55 years (range 41-81). The most common site of involvement was the tongue/floor of mouth (77% of cases). Of the 53 cases, 94% exhibited parakeratosis and/or hyperkeratosis. All the cases featured karyorrhexis, apoptosis, and characteristics of conventional carcinoma in situ. The quantity of DNA extracted was sufficient for analysis in 22 cases. HPV-16 was identified in 20/22 (91%) cases. One case was associated with HPV-33 and one with HPV-58 (5% each). Eight of the 53 cases (15%) were associated with invasive squamous cell carcinomas.

HPV vaccine acceptability in high-risk Greek men

HPV is associated with malignancy in men, yet there is a lack of data on HPV knowledge, vaccine acceptability, and factors affecting vaccine acceptability in Greek men. This study aims to identify determinants of knowledge and willingness to vaccinate against HPV among high-risk Greek men. Men (n = 298) between the ages of 18 and 55 were enrolled from the STI and HIV clinics at "Andreas Syggros" Hospital in Athens, Greece from July-October 2015. Participants completed a survey on demographics, economic factors, sexual history, HPV knowledge, and vaccine acceptability. The majority of participants were younger than 40 (76.6%) and unmarried (84.6%). Our sample was 31.2% MSM (men who have sex with men), and 20.1% were HIV-positive. Most participants (>90%) were aware that HPV is highly prevalent in both men and women; however, fewer identified that HPV causes cancers in both sexes (68%) and that vaccination protects men and women (67%). Amongst participants, 76.7% were willing to vaccinate themselves against HPV, 71.4% an adolescent son, and 69.3% an adolescent daughter. HIV-positive men were more likely to be willing to vaccinate themselves (OR 2.83, p = .015), a son (OR 3.3, p = .015) or a daughter (3.01, p = .020). Higher income levels were associated with increased willingness to vaccinate oneself (OR 1.32, p = .027), a son (1.33, p = .032) or daughter (1.34, p = .027). Although there is a HPV knowledge gap, HPV vaccine acceptability is high despite lack of vaccine promotion to Greek men. Future studies should include lower-risk men to adequately inform public health efforts.

Oral sex and human papilloma virus-related head and neck squamous cell cancer: a review of the literature

Head neck squamous cell carcinomas (HNSCCs) are a significant cause of morbidity and mortality all around the world. Just like tobacco and alcohol, Human papilloma virus (HPV) infection is now recognized to play a role in the pathogenesis of a subset of HNSCCs. Unprotected sexual behaviours with the HPV carrier plays an important role in transmission of this virus. The global incidence of head and neck cancers is declining, but the incidence of HPV related head and neck cancers is rapidly increasing over the last few decades. However, most institutions do not mandate documentation of sexual history or counselling of patients regarding sexual practices like they do for tobacco and alcohol addictions in HNSCC patients. The aim of this review of literature is to analyse if there is a strong evidence to correlate oral sex with HPV related HNSCC and counsel the patient's regarding sexual behaviours.

Oral human papillomavirus infection, sexual behaviors and risk of oral squamous cell carcinoma in southeast of China: A case-control study

BACKGROUND

The causal association between human papillomavirus (HPV) and oral squamous cell carcinoma (OSCC) remains controversial. Most of previous studies did not consider the potential modification effect of sexual behaviors when evaluating the role of HPV infection in OSCC risk.

OBJECTIVES

To explore the independent and joint effects of oral HPV infection and sexual behaviors on OSCC in Chinese population.

STUDY DESIGN

A case-control study was conducted from September 2012 to September 2015 in Fujian, China. HPV DNA genotypes were detected in tumor tissues of 178 OSCC patients and oral exfoliated cells of 189 frequency-matched controls using flow-through hybridization and gene chip. Epidemiologic data were collected with a structured questionnaire by face-to-face interviews. Odds ratios (ORs) and 95% confidence interval (CI) were estimated with unconditional logistic regression models.

RESULTS

The overall HPV prevalence was 14.04% in OSCC patients and 3.17% in controls. HPV-18 was the most prevalent type in cases and controls (10.67% vs. 2.12%). Oral HPV infection was strongly associated with an increased risk of OSCC: the ORs were 7.21 (95% CI: 2.61-19.88) for HPV16/18 and 7.59 (95% CI: 2.34-24.64) for HPV-18. Moreover, the significant associations were only observed in females, young adults, married population, merchants, non-smokers, non-alcohol drinkers and non-tea drinkers. Additionally, the first intercourse below 22years of age and oral sex practice did not show an association with OSCC. But there was a significantly multiplicative interaction between HPV 16/18 and age at first intercourse for OSCC (P_interaction<0.001).

CONCLUSIONS

Oral HPV infection (specifically type 18) is an independent risk factor for OSCC in Fujian area. Furthermore, there might be a combined effect of HPV 16/18 and age at first intercourse on OSCC.

Beta-HPV types in patients with head and neck pathology and in healthy subjects

BACKGROUND

Human papillomaviruses (HPV) are a heterogeneous group of viruses classified into five genera. The beta-HPV type (beta-PV) infection is very common but mostly asymptomatic in immunocompetent individuals. However, beta-PVs play a role in Epidermodysplasia verruciformis and possibly in non-melanoma skin cancer. Head and neck cancer (HNC) is a common cancer type worldwide and high-risk alpha-PV involvement in HNC has been extensively studied but beta-PV types have rarely been the focus of such studies.

OBJECTIVES

To evaluate the prevalence of beta-PV types in HNC, subjects with non-malignant or potentially pre-malignant oral lesions, and healthy controls.

STUDY DESIGN

The frequency of different beta-PVs in samples from oral (n=35) and oropharyngeal (n=35) cancer patients, gender- and age-matched healthy controls (n=70), and subjects with various non-malignant or potentially pre-malignant oral lesions (n=102) was assessed by a highly sensitive, bead-based, multiplex genotyping assay.

RESULTS

Overall, 54.8% of all tested samples contained at least one beta-PV type. Even though the correlation between types found in lavage and tissue specimens from cancer patients was low, there was a large statistically significant difference between oropharyngeal cancer patients and matched controls for HPV5 (P=0.003; OR=15.58) and between both oral (P=0.026; OR=5.7) and oropharyngeal cancer patients (P=0.002; OR=25.5) and controls for HPV122. In addition, there was no correlation between the prevalence of alpha and beta-PVs in the study patients.

CONCLUSION

The study provides new data on the prevalence of beta-PVs in HNC. HPV5 was found significantly associated with HNC as already observed by other studies. Additionally, the significant association of HPV122 with HNC might warrant further study as this type has not been extensively studied so far.

Oral Human Papillomavirus Infection in Men Who Have Sex with Men: A Systematic Review and Meta-Analysis

BACKGROUND

The epidemiology of oral human papillomavirus (HPV) infection in men who have sex with men (MSM) differs from anogenital HPV infection. The impact of HPV vaccination has, to date, largely focussed on anogenital outcomes. Vaccination of MSM in the UK has been recommended and, if implemented, baseline estimates of oral HPV prevalence will be useful.

METHODS

We searched Medline, Embase and psycINFO databases for studies reporting prevalence, incidence, and clearance of oral HPV infection in MSM. We performed a random-effects meta-analysis and meta-regression on prevalence estimates and summarised within-study risk factors for oral HPV DNA detection and incidence/clearance rates. We also performed a meta-analysis of the effect of MSM on oral HPV prevalence compared to heterosexual men.

RESULTS

26 publications were identified. The pooled prevalence of oral HPV16 from twelve estimates was 3.0% (95%CI 0.5-5.5) in HIV-negative and 4.7% (95%CI 2.1-7.3) in HIV-positive MSM. Median age of study participants explained 38% of heterogeneity (p<0.01) in HPV prevalence estimates (pooled = 17% and 29% in HIV-negative and HIV-positive, respectively; 22 estimates). Nine studies compared MSM to heterosexual men and found no difference in oral HPV prevalence (pooled OR 1.07 (95%CI 0.65-1.74)). The clearance rate was higher than incidence within studies. Type-specific concordance between oral and anogenital sites was rare.

CONCLUSION

There was substantial heterogeneity between estimates of oral HPV prevalence in MSM populations that was partly explained by HIV status and median age.

Sex Differences in Risk Factors and Natural History of Oral Human Papillomavirus Infection

Oral human papillomavirus genotype 16 (HPV16) infection causes oropharyngeal squamous cell carcinoma (SCC), and the prevalence of oropharyngeal SCC is higher among men than women in the United States. In a cohort study of oral HPV infection among 409 individuals aged 18-25 years, the risk among men but not among women significantly increased as the number of recent (ie, within the prior 3 months) oral sex partners increased (Pinteraction = .05). In contrast, the risk among women but not among men significantly decreased as the lifetime number of vaginal sex partners increased (Pinteraction = .037). Men were also significantly less likely than women to clear oral HPV infection. Our data contribute to understanding sex differences in risk for HPV-positive oropharyngeal SCC.

CLINICAL TRIALS REGISTRATION

NCT00994019.

Prevalence of and Risk Factors for Oral Human Papillomavirus Infection among HIV-Positive and HIV-Negative People Who Inject Drugs

Background

Human papillomavirus (HPV) causes most oropharyngeal cancers in the United States. Oral HPV prevalence is associated with immunosuppression, and drug use can be immunosuppressive, but the epidemiology of oral HPV among people who use drugs is not well described.

Methods

We enrolled men and women with a current or prior history of injection drug use in this cross-sectional sub-study within the AIDS Linked to the Intravenous Experience (ALIVE) cohort. We tested oral rinse samples for 37 types of HPV DNA and collected self-reported risk factor information. We compared oral HPV prevalence across categories using chi-squared statistics and multivariable logistic regression.

Results

Among 199 subjects, 32% were HIV-positive (median CD4 count 384 cells/μL), 90% were Black, 56% had less than a high school education, 17% had recently used injection drugs, and the median age was 54 years. Most had performed oral sex (82%) but had fewer than 5 lifetime partners (58%). The prevalence of any oral HPV was 29%, and of any oncogenic oral HPV was 13%. Oral HPV prevalence was high among both heterosexual men (30%) and women (20%). After adjustment, odds of oral HPV were increased among HIV-positive individuals with a low CD4 count (<350 cells/μl, aOR = 2.7, 95%CI = 1.2–6.4, vs. HIV-negative individuals), but not among HIV-positive individuals with a higher CD4 cell count. Odds were also elevated for those who had recently performed oral sex on a woman (aOR = 2.2, 95%CI = 1.01–4.6) and, even after this adjustment, among bisexual/lesbian females (aOR = 5.6, 95%CI = 1.4–23, vs. heterosexual females). Oral HPV prevalence was not associated with vaginal sex, performing oral sex on a man, or recent drug use.

Conclusions

Recent drug use was not associated with oral HPV prevalence in our study. However, despite modest numbers of sexual partners, the prevalence of oral HPV among this largely Black population with lower socioeconomic status was high.

The impact of sexual behavior on oral HPV infections in young unvaccinated adults

OBJECTIVE

Different authors hypothesized an important impact of sexual behavior on the prevalence of oral human papillomavirus (HPV) infections. In order to investigate this relationship more in detail and in contrast to most other studies, the present work focused on the population group with the highest risk for sexually transmitted infections: young and sexual active adults.

MATERIALS AND METHODS

Three hundred and ten men and women aged 18-30 years could be recruited. After the completion of a risk-factor survey, brush smear samples for oral HPV detection were taken in every participant.

RESULTS

In 18.1 %, oral HPV could be detected. Overall, smoking (p = 0.0074) and a high number of different sexual partners (vaginal: p = 0.0001; oral: p < 0.0001) were significantly correlated with a positive HPV testing. In case of high risk HPV infections, besides tobacco and sexual behavior, alcohol consumption showed a significant association with a positive testing (p = 0.0212).

CONCLUSIONS

Overall, the prevalence of oral HPV seems to be higher in young, sexual active adults compared to other population groups. Tobacco and alcohol may facilitate an oral HPV infection. Sexual behavior, especially oral sex practices, seems to play a crucial role in the transmission of oral HPV.

CLINICAL RELEVANCE

The presented data, especially the association of oral high risk HPV positivity and promiscuity, may lead to improvements in the existing oral HPV prevention strategies like a HPV vaccination for both genders.

Epidemiology of Human Papillomavirus-Positive Head and Neck Squamous Cell Carcinoma

Human papillomavirus (HPV) is now established as the principal cause of an increase in incidence of a subset of head and neck squamous cell cancers (HNCs) in numerous geographic regions around the world. Further study of the epidemiology of HPV-positive HNC will be critical to the development and implementation of public health interventions to reverse these global incidence trends. Here, recent data are reviewed to provide insight into several topics, including incidence trends and projections for HPV-positive HNC; the worldwide HPV-attributable fraction; sex disparities in cancer risk; the epidemiology of oral HPV infection; the latency period between infection and cancer; the potential impact of prophylactic HPV vaccination; and prospects for secondary prevention through screening for oral HPV infection or seroreactivity to viral antigens. The identification of a single necessary cause for any cancer provides a rare and perhaps extraordinary opportunity for cancer prevention.

Epidemiology of head and neck cancer

This article discusses risk factors, incidence trends, and prognostic considerations for head and neck cancer (HNC). The primary causes of HNC are tobacco and alcohol use, and human papillomavirus (HPV). Tobacco-related HNC incidence rates are decreasing in countries where tobacco use has declined. HPV-HNC, which occurs primarily in the oropharynx and is associated with sexual behaviors, has been increasing over the past several decades, among white men in particular. The prognosis for HNC overall has improved slightly since the 1990s, and is influenced by site, stage, and HPV status. Prognosis for HPV-HNC is significantly better than for HPV-negative disease.