Reduced prevalence of oral human papillomavirus (HPV) 4 years after bivalent HPV vaccination in a randomized clinical trial in Costa Rica

Targeted Therapy in Oropharyngeal Squamous Cell Carcinoma: The Implications of HPV for Therapy

Oropharyngeal cancers caused by human papillomaviruses (HPV) have a different epidemiology, prognosis, genetic mutational landscape, response to treatment, and outcome when compared to HPV-negative cancers. In this review, a summary of our current understanding of HPV in head and neck cancer and the important advances that have shown HPV to be an etiological agent are discussed. HPV-positive and HPV-negative tumors are compared discussing clinicopathological factors, prognosis, outcome following treatment, and the molecular and genetic differences. Currently, the standard of care for oropharyngeal cancer is both surgery and post-operative radiotherapy with or without cisplatin or concurrent chemo-radiotherapy. The latter is used more often, especially in cancers of tonsil and base of tongue. However, there is increased interest in trying to de-intensify treatment and in the development of new treatments to target the underlying different molecular pathways of HPV-positive cancers. The current clinical trials involving surgery, chemotherapy, and radiation therapy are discussed. The new targeted treatments are also summarized. Although there is currently is no evidence from prospective studies to support a change in the treatment algorithm, the treatment options for patients with HPV-positive disease are likely to change in the future.

Molecular cancer prevention: Current status and future directions

The heterogeneity and complexity of advanced cancers strongly support the rationale for an enhanced focus on molecular prevention as a priority strategy to reduce the burden of cancer. Molecular prevention encompasses traditional chemopreventive agents as well as vaccinations and therapeutic approaches to cancer-predisposing conditions. Despite challenges to the field, we now have refined insights into cancer etiology and early pathogenesis; successful risk assessment and new risk models; agents with broad preventive efficacy (eg, aspirin) in common chronic diseases, including cancer; and a successful track record of more than 10 agents approved by the US Food and Drug Administration for the treatment of precancerous lesions or cancer risk reduction. The development of molecular preventive agents does not differ significantly from the development of therapies for advanced cancers, yet it has unique challenges and special considerations given that it most often involves healthy or asymptomatic individuals. Agents, biomarkers, cohorts, overall design, and endpoints are key determinants of molecular preventive trials, as with therapeutic trials, although distinctions exist for each within the preventive setting. Progress in the development and evolution of molecular preventive agents has been steadier in some organ systems, such as breast and skin, than in others. In order for molecular prevention to be fully realized as an effective strategy, several challenges to the field must be addressed. Here, the authors provide a brief overview of the context for and special considerations of molecular prevention along with a discussion of the results from major randomized controlled trials.

Oral cavity and oropharyngeal squamous cell carcinoma--an update

Oral cavity squamous cell carcinoma (OC-SCC) is the most common malignancy of the head and neck (excluding nonmelanoma skin cancer). Recent trends have shown a dramatic rise in the incidence of oropharyngeal squamous cell carcinoma (OP-SCC), with a marked increase in lesions related to human papillomavirus infection. This update presents the latest evidence regarding OC-SCC and OP-SCC. In particular, the authors compare and contrast tumors at these two sites with respect to epidemiology, etiopathogenesis, clinicopathologic presentation, clinical assessment, imaging, management, and prognosis. It is important for clinicians to be aware of differences between OC-SCC and OP-SCC so that appropriate patient education and multidisciplinary care can be provided to optimize outcomes.

A different entity: a population based study of characteristics and recurrence patterns in oropharyngeal squamous cell carcinomas

Background

Cases of squamous cell carcinoma (SCC) of the oropharynx were compared with other head and neck cancer (HNC) anatomic subsites in patients treated at the provincial referral centre for HNC, the Nova Scotia Cancer Centre (NSCC).

Methods

A retrospective chart review was performed on HNC patients assessed at the NSCC between 2010 and 2011. Patient demographics, disease characteristics, treatment details and outcomes, including recurrence rates and survival were collected. Data was collected on new and recurrent cases of HNC. This data was compared between the two types of HNC using chi-square tests for dichotomous categorical variables or Fishers exact test where appropriate. Wald test was used to compare categorical variables with 3 categories. Continuous variables were compared using the non-parametric Wilcoxon test.

Results

318 charts were included in the analysis. 122 (38 %) were oropharyngeal squamous cell carcinomas (OPSCCs). In terms of disease characteristics, OPSCCs were more likely to be poorly differentiated/undifferentiated (n = 267, 49(40 %) vs 42(21 %), p < 0.001), non-keratinizing (n = 169, 25(20 %) vs 17(9 %), p < 0.001), greater than 2 cm (n = 253, 72(59 %) vs 78(40 %), p = 0.0061), stage 4 (n = 313, 55(45 %) vs 64(33 %), p = 0.0315) and have had locoregional nodal spread (n = 315, 103(84 %) vs 55(28 %), p < 0.001). In the subset of 57 patients that had p16 testing, OPSCCs were more likely to be p16(+) (37(30 %) vs 1(1 %), p < .001). There were no significant differences in terms of Charlson probability of 10 year survival, smoking or alcohol consumption although OPSCC patients were significantly less likely to have COPD as a co-morbidity (n = 318, 19(16 %) vs 53(27 %), p = 0.0175). Finally, OPSCCs had less chance for relapse than non-OPSCCs in both univariate (2.119 times less, p=0.0034) and multivariate (1.899 times less, p=0.0505) analyses along with a 1.822 times less overall mortality in a multivariae analysis (p=0.0408). 

Conclusions

This analysis suggests that Nova Scotian OPSCCs should be considered distinct from other HNC lesions, most notably in terms of disease characteristics and prognosis. Specifically, despite a higher association with disease factors traditionally considered to be linked to poor prognosis, outcomes were actually superior in terms of relapse and overall mortality.

Emerging and changing viral diseases in the new millennium

Most viral infections encountered in resource‐rich countries are relatively trivial and transient with perhaps fever, malaise, myalgia, rash (exanthema) and sometimes mucosal manifestations (enanthema), including oral in some. However, the apparent benignity may be illusory as some viral infections have unexpected consequences – such as the oncogenicity of some herpesviruses and human papillomaviruses. Infections are transmitted from various human or animal vectors, especially by close proximity, and the increasing movements of peoples across the globe, mean that infections hitherto confined largely to the tropics now appear worldwide. Global warming also increases the range of movement of vectors such as mosquitoes. Thus recent decades have seen a most dramatic change with the emergence globally also of new viral infections – notably human immunodeficiency viruses (HIV) – and the appearance of some other dangerous and sometimes lethal infections formerly seen mainly in, and reported from, resource‐poor areas especially in parts of Asia, Latin America and Africa. This study offers a brief update of the most salient new aspects of the important viral infections, especially those with known orofacial manifestations or other implications for oral health care.

HPV prophylactic vaccines: lessons learned from 10 years experience

When HPV vaccines were registered in 2006/2007, it was unclear whether these new and type-specific prophylactic vaccines would be accepted by the community for cancer prevention. With an optimal vaccination age of early adolescence, three vaccine doses required, HPV a sexually transmitted infection, and secondary prevention already available in the form of cervical screening, considerable potential challenges were faced. At the time of licensing, vaccine efficacy in males and duration of immunity were not yet unknown. Almost a decade later, with over 230 million doses of the vaccines distributed worldwide and national HPV vaccination programs in place in many countries, it is timely to reflect on current knowledge about the vaccines and some of the lessons learned during implementation.

The "HPV Discussion": Effective Use of Data to Deliver Recommendations to Patients Impacted by HPV

OBJECTIVE

The dramatic rise in oropharyngeal squamous cell carcinoma associated with the human papilloma virus (HPV) has brought significant change to the interaction between patients and head and neck oncologists. HPV-induced cancers are generally the result of elements from the patient's sexual history, and otolaryngologists are generally less experienced than primary care physicians in addressing patient questions relating to sexual history and practices. This article addresses questions commonly posed by patients relating to HPV-induced head and neck cancers, issues related to HPV vaccination, and surveillance of HPV-related lesions. Supporting data are provided such that physicians may be better equipped to sufficiently address patient queries on this topic.

DATA SOURCES

Available peer-reviewed literature and clinical practice guidelines.

REVIEW METHODS

Assessment and discussion of specific topics by authors selected from the Head and Neck Surgery Education Committee of the American Academy of Otolaryngology-Head and Neck Surgery Foundation.

RESULTS

An educational "miniseminar" resulted in a notable increase in attendee knowledge and comfort regarding oropharyngeal squamous cell carcinoma counseling for patients in the setting of HPV-positive disease.

CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

The dramatic increase in HPV-associated head and neck cancers has resulted in a changed paradigm of the physician-patient interaction. Care providers in today's environment must be prepared to counsel patients regarding sexually transmitted diseases and high-risk sexual behaviors. Examination of the existing data provides the foundation with which to construct a framework in which physicians can effectively communicate information and recommendations as they pertain to HPV-related carcinoma.

Immunotherapy of HPV-associated cancer: DNA/plant-derived vaccines and new orthotopic mouse models

Under the optimistic assumption of high-prophylactic HPV vaccine coverage, a significant reduction of cancer incidence can only be expected after decades. Thus, immune therapeutic strategies are needed for persistently infected individuals who do not benefit from the prophylactic vaccines. However, the therapeutic strategies inducing immunity to the E6 and/or E7 oncoprotein of HPV16 are more effective for curing HPV-expressing tumours in animal models than for treating human cancers. New strategies/technologies have been developed to improve these therapeutic vaccines. Our studies focussed on preparing therapeutic vaccines with low-cost technologies by DNA preparation fused to either plant-virus or plant-toxin genes, such as saporin, and by plant-produced antigens. In particular, plant-derived antigens possess an intrinsic adjuvant activity that makes these preparations especially attractive for future development. Additionally, discrepancy in vaccine effectiveness between animals and humans may be due to non-orthotopic localization of animal models. Orthotopic transplantation leads to tumours giving a more accurate representation of the parent tumour. Since HPV can cause cancer in two main localizations, anogenital and oropharynx area, we developed two orthotopic tumour mouse models in these two sites. Both models are bioluminescent in order to follow up the tumour growth by imaging and are induced by cell injection without the need to intervene surgically. These models were utilized for immunotherapies with genetic or plant-derived therapeutic vaccines. In particular, the head/neck orthotopic model appears to be very promising for studies combining chemo-radio-immune therapy that seems to be very effective in patients.

Increase in head and neck cancer in younger patients due to human papillomavirus (HPV)

The face of head and neck cancer has changed dramatically over the past 30 years. There has been a steady decline in the number of tobacco and alcohol related squamous cell carcinomas over the past 30 years, but and increasing incidence of human papillomavirus (HPV) related cancers. Some estimates suggest that 70-90% of new oropharyngeal cancers have evidence of HPV. These patients have different demographic patterns, in that they are more likely to be younger, white adults in their 40s and 50s who are never smokers or have reduced tobacco exposure. Studies have shown that a higher number of lifetime oral sex partners (>5) and a higher number of lifetime vaginal sex partners (>25) have been associated with increased risk of HPV positive head and neck cancer. People can also reduce their risk of HPV linked head and neck cancer by receiving the HPV vaccine series prior to becoming sexually active. Recent evidence suggests HPV related head and neck cancers present with different symptoms than those caused by tobacco. The most popular test for HPV status is the p16 immunohistochemical stain because it is cheap, simple, and studies have shown it to have comparable sensitivity and specificity to the previous standards. It is widely recommended that all cancers of the oropharynx be tested for the presence of HPV, and some recommend it for all head and neck cancers. Overall 2-year and 5-year survival for HPV positive head and neck cancer is significantly greater than for HPV negative cancers, likely due to HPV positive cancers being more responsive to treatment.

From the monovalent to the nine-valent HPV vaccine

An investigational monovalent human papillomavirus (HPV) 16 virus-like particle vaccine has been shown to prevent persistent infection and cervical disease related to HPV 16 and was proof of concept (2002). Designed to prevent the bulk of invasive cervical cancer, quadrivalent (HPV 6/11/16/18) and bivalent (HPV 16/18) vaccines have been available since 2006 and 2007, respectively. They are highly effective in preventing HPV 16/18-related cervical precancer; the quadrivalent version also prevents genital warts related to HPV 6/11. It has been shown that the precursors of vulvar, vaginal and anal cancer related to the vaccine types are effectively prevented. This led to a paradigm shift from a female-only cervical cancer vaccine to a vaccine for the prevention of HPV-related disease and cancer for both sexes. Vaccination before the start of sexual activity is most effective, and consequently most programs target 9- to 12-year-olds. Additionally, recent studies have proven the noninferior immunoresponse of a two-dose schedule in these age cohorts. Gender-neutral vaccination has become more common; it improves coverage and also provides protection to all males. Recently a nine-valent HPV vaccine (HPV 6/11/16/18/31/33/45/52/58) was licensed; it provides high and consistent protection against infections and diseases related to these types, with ∼90% of cervical and other HPV-related cancers and precancers potentially being avoided. Coverage is key. Efforts must be made to provide HPV vaccination in low-resource countries that lack screening programs. In countries with cervical cancer screening, HPV vaccination will greatly affect screening algorithms.

Direct benefit of vaccinating boys along with girls against oncogenic human papillomavirus: bayesian evidence synthesis

OBJECTIVE

To assess the reduction in the vaccine preventable burden of cancer in men if boys are vaccinated along with girls against oncogenic human papillomavirus (HPV).

DESIGN

Bayesian evidence synthesis approach used to evaluate the impact of vaccination against HPV types 16 and 18 on the burden of anal, penile, and oropharyngeal carcinomas among heterosexual men and men who have sex with men. The reduced transmission of vaccine-type HPV from vaccination of girls was assumed to lower the risk of HPV associated cancer in all men but not to affect the excess risk of HPV associated cancers among men who have sex with men.

SETTING

General population in the Netherlands.

INTERVENTION

Inclusion of boys aged 12 into HPV vaccination programmes.

MAIN OUTCOME MEASURES

Quality adjusted life years (QALYs) and numbers needed to vaccinate.

RESULTS

Before HPV vaccination, 14.9 (95% credible interval 12.2 to 18.1) QALYs per thousand men were lost to vaccine preventable cancers associated with HPV in the Netherlands. This burden would be reduced by 37% (28% to 48%) if the vaccine uptake among girls remains at the current level of 60%. To prevent one additional case of cancer among men, 795 boys (660 to 987) would need to be vaccinated; with tumour specific numbers for anal, penile, and oropharyngeal cancer of 2162, 3486, and 1975, respectively. The burden of HPV related cancer in men would be reduced by 66% (53% to 805) if vaccine uptake among girls increases to 90%. In that case, 1735 boys (1240 to 2900) would need to be vaccinated to prevent an additional case; with tumour specific numbers for anal, penile, and oropharyngeal cancer of 2593, 29107, and 6484, respectively.

CONCLUSIONS

Men will benefit indirectly from vaccination of girls but remain at risk of cancers associated with HPV. The incremental benefit of vaccinating boys when vaccine uptake among girls is high is driven by the prevention of anal carcinomas, which underscores the relevance of HPV prevention efforts for men who have sex with men.

Present status of human papillomavirus vaccine development and implementation

Oncogenic human papillomavirus (HPV) infection is the cause of nearly all cervical cancers and a proportion of other anogenital and oropharyngeal cancers. A bivalent vaccine containing HPV 16 and 18 and a quadrivalent vaccine containing HPV 6, 11, 16, and 18 antigens are in use in vaccination programmes around the world. In clinical trials, three vaccine doses provided 90-100% protection against cervical infection and pre-cancer related to HPV 16 and 18 in women aged 15-26 years who were not infected at vaccination. Partial cross-protection against other HPV types has been reported but its duration is unknown. The vaccines were also efficacious at the prevention of HPV 16 and 18 infections at other anatomical sites in both sexes. Immunobridging studies allowed licensing of the vaccines for use starting at age 9 years for both sexes. Two-dose schedules elicit high antibody concentrations, leading to the recommendation of two-dose schedules for girls aged 9-14 years. Pre-licensure and post-licensure studies have provided data supporting vaccine safety. In 2014, a nonavalent vaccine containing HPV 6, 11, 16, 18, 31, 33, 45, 52, and 58 antigens was licensed by the US Food and Drug Administration. HPV vaccination was first introduced in high-income countries owing to vaccine cost, logistic challenges, and competing health priorities. Since 2011, vaccine prices have lowered, allowing the introduction of the vaccine in some middle-income countries. Funding of the vaccine by the GAVI Alliance in 2012 led to demonstration projects in some low-income countries. By 2014, more than 57 countries had included the HPV vaccine in their national health programmes. Data from several countries have shown the effect of vaccination on HPV infection and associated disease, and provided evidence of herd immunity. Expansion of programmes to countries with the highest burden of disease is beginning, but further efforts are needed to realise the potential of HPV vaccines.

US assessment of HPV types in cancers: implications for current and 9-valent HPV vaccines

BACKGROUND

This study sought to determine the prevaccine type-specific prevalence of human papillomavirus (HPV)-associated cancers in the United States to evaluate the potential impact of the HPV types in the current and newly approved 9-valent HPV vaccines.

METHODS

The Centers for Disease Control and Prevention partnered with seven US population-based cancer registries to obtain archival tissue for cancers diagnosed from 1993 to 2005. HPV testing was performed on 2670 case patients that were fairly representative of all participating cancer registry cases by age and sex. Demographic and clinical data were evaluated by anatomic site and HPV status. Current US cancer registry data and the detection of HPV types were used to estimate the number of cancers potentially preventable through vaccination.

RESULTS

HPV DNA was detected in 90.6% of cervical, 91.1% of anal, 75.0% of vaginal, 70.1% of oropharyngeal, 68.8% of vulvar, 63.3% of penile, 32.0% of oral cavity, and 20.9% of laryngeal cancers, as well as in 98.8% of cervical cancer in situ (CCIS). A vaccine targeting HPV 16/18 potentially prevents the majority of invasive cervical (66.2%), anal (79.4%), oropharyngeal (60.2%), and vaginal (55.1%) cancers, as well as many penile (47.9%), vulvar (48.6%) cancers: 24 858 cases annually. The 9-valent vaccine also targeting HPV 31/33/45/52/58 may prevent an additional 4.2% to 18.3% of cancers: 3944 cases annually. For most cancers, younger age at diagnosis was associated with higher HPV 16/18 prevalence. With the exception of oropharyngeal cancers and CCIS, HPV 16/18 prevalence was similar across racial/ethnic groups.

CONCLUSIONS

In the United States, current vaccines will reduce most HPV-associated cancers; a smaller additional reduction would be contributed by the new 9-valent vaccine.

Rationale and design of a long term follow-up study of women who did and did not receive HPV 16/18 vaccination in Guanacaste, Costa Rica

The Costa Rica Vaccine Trial (CVT) was a randomized clinical trial conducted between 2004 and 2010, which randomized 7466 women aged 18 to 25 to receive the bivalent HPV-16/18 vaccine or control Hepatitis-A vaccine. Participants were followed for 4 years with cross-over vaccination at the study end. In 2010 the long term follow-up (LTFU) study was initiated to evaluate the 10-year impact of HPV-16/18 vaccination, determinants of the immune response, and HPV natural history in a vaccinated population. Herein, the rationale, design and methods of the LTFU study are described, which actively follows CVT participants in the HPV-arm 6 additional years at biennial intervals (3 additional study visits for 10 years of total follow-up), or more often if clinically indicated. According to the initial commitment, women in the Hepatitis-A arm were offered HPV vaccination at cross-over; they were followed 2 additional years and exited from the study. 92% of eligible CVT women accepted participation in LTFU. To provide underlying rates of HPV acquisition and cervical disease among unvaccinated women to compare with the HPV-arm during LTFU, a new unvaccinated control group (UCG) of women who are beyond the age generally recommended for routine vaccination was enrolled, and will be followed by cervical cancer screening over 6 years. To form the UCG, 5000 women were selected from a local census, of whom 2836 women (61% of eligible women) agreed to participate. Over 90% of participants complied with an interview, blood and cervical specimen collection. Evaluation of comparability between the original (Hepatitis-A arm of CVT) and new (UCG) control groups showed that women's characteristics, as well as their predicted future risk for cervical HPV acquisition, were similar, thus validating use of the UCG. LTFU is poised to comprehensively address many important questions related to long-term effects of prophylactic HPV vaccines.

Advancements in the Management of HPV-Associated Head and Neck Squamous Cell Carcinoma

Head and neck carcinomas have long been linked to alcohol and tobacco abuse; however, within the last two decades, the human papillomavirus (HPV) has emerged as a third etiology and is specifically associated with head and neck squamous cell carcinomas (HNSCC). In this anatomical region, the oncogenic HPV-16 mediates transformation and immortalization of epithelium, most commonly in the oropharynx. Nevertheless, the recent identification of novel HPV mechanisms thought to be specific to oropharyngeal carcinogenesis has coincided with observations that HPV-associated HNSCC has differing clinical behavior-in terms of natural history, therapeutic response, and prognosis-than HPV-negative head and neck tumors. Taken together with the growing incidence of HPV transmission in younger populations, these discoveries have sparked a rapid expansion in both laboratory and clinical studies on the infection and disease. Herein, we review the clinical characteristics of HPV-associated HNSCC, with particular emphasis on recent advancements in our understanding of the management of this infectious malignancy.

NHANES 2009-2012 Findings: Association of Sexual Behaviors with Higher Prevalence of Oral Oncogenic Human Papillomavirus Infections in U.S. Men

The incidence of human papillomavirus (HPV)-positive oropharyngeal cancers is higher and increasing more rapidly among men than women in the United States for unknown reasons. We compared the epidemiology of oral oncogenic HPV infection between men and women ages 14 to 69 years (N = 9,480) within the U.S. National Health and Nutritional Examination Surveys (NHANES) 2009-2012. HPV presence was detected in oral DNA by PCR. Analyses were stratified by gender and used NHANES sample weights. Oral oncogenic HPV prevalence was higher among men than women (6.6% vs. 1.5%, P < 0.001), corresponding to 7.07 million men versus 1.54 million women with prevalent infection at any point in time during 2009-2012. Prevalence increased significantly with age, current smoking, and lifetime number of sexual partners for both genders (adjusted Ptrend < 0.02). However, men had more partners than women (mean = 18 vs. 7, P < 0.001). Although oncogenic HPV prevalence was similar for men and women with 0 to 1 lifetime partners, the male-female difference in prevalence significantly increased with number of lifetime partners (adjusted prevalence differences for none, 1, 2-5, 6-10, 11-20, and 20+ partners = 1.0%, 0.5%, 3.0%, 5.7%, 4.6%, and 9.3%, respectively). Importantly, the per-sexual partner increase in prevalence was significantly stronger among men than among women (adjusted synergy index = 3.3; 95% confidence interval, 1.1-9.7), and this increase plateaued at 25 lifetime partners among men versus 10 partners among women. Our data suggest that the higher burden of oral oncogenic HPV infections and HPV-positive oropharyngeal cancers among men than women arises in part from higher number of lifetime sexual partners and stronger associations with sexual behaviors among men.

A cost-effectiveness analysis of human papillomavirus vaccination of boys for the prevention of oropharyngeal cancer

BACKGROUND

Many western countries have established female human papillomavirus (HPV) vaccination programs for the prevention of cervical cancer. The quadrivalent HPV vaccine (HPV4) has proven efficacy against additional HPV-related disease in both sexes, but the cost effectiveness of male HPV vaccination remains controversial. To assess the cost effectiveness of male HPV vaccination in Canada with respect to oropharyngeal cancer (OPC), the authors performed a preliminary cost-effectiveness analysis.

METHODS

After an extensive literature review regarding HPV-related OPC in Canadian males, health care costs and clinical effectiveness estimates were obtained. A Markov model was used to compare the potential costs and effectiveness of HPV4 versus no vaccination among boys aged 12 years. A theoretical cohort based on a Canadian population of 192,940 boys aged 12 years in 2012 was assumed to apply the model. A 3-month cycle length was used with a "lifetime" time horizon. The outcome of the analysis was the incremental cost per quality-adjusted life-year (QALY). Sensitivity analyses were conducted on variables, including the vaccine uptake rate and vaccine efficacy.

RESULTS

Assuming 99% vaccine efficacy and 70% uptake, HPV4 produced 0.05 more QALYs and saved $145 Canadian dollars (CAD) per individual compared with no vaccine (QALYs and costs were discounted at 5% per year). Assuming 50% vaccine efficacy and 50% uptake, HPV4 produced 0.023 more QALYs and saved $42 CAD. The results indicated that HPV4 in males may potentially save between $8 and $28 million CAD for the theoretical cohort of 192,940 over its lifetime.

CONCLUSIONS

On the basis of this model, HPV vaccination for boys aged 12 years may be a cost-effective strategy for the prevention of OPC in Canada.

Trends in head and neck cancers in England from 1995 to 2011 and projections up to 2025

BACKGROUND

The magnitude of the growing burden of oropharyngeal cancers (OPC), a sub-set of head and neck cancers (HNC), is unknown in England.

METHODS

Data were extracted from population-based cancer registries in England. The burden of HNC overall and by anatomic site was described from 1995 to 2011. Projections of future rates up to 2025 were estimated using flexible age-period-cohort modelling.

RESULTS

HNC increased by 59% between 1995 and 2011 in England. Projections indicate that the number of HNC cases will increase by 55% from 2011, totalling 11,748 new cases in 2025, ranking HNC as the sixth most common cancer. Of the anatomic sites, OPC is projected to account for 35% of HNC with the largest rate increase (annual percentage change, +7.3% for men and +6.2% for women between 2011 and 2025), predominantly affecting males <60years. This projected burden is equivalent to a 239% increase in number of OPC cases. Incidence of the oral cavity, salivary glands and palate are projected to rise at lower rates, whereas rates of the nasopharynx, hypopharynx and larynx remain relatively stable or decreasing.

CONCLUSION

The substantial recent and predicted future significant increase in OPC highlights the need for prioritising the provision of cancer services for the considerable burden of OPC patients and survivors and cancer control strategies.

Human papillomavirus and tonsillar and base of tongue cancer

In 2007, human papillomavirus (HPV) type 16 was recognized as a risk factor by the International Agency for Research on Cancer, for oropharyngeal squamous cell carcinoma (OSCC), where tonsillar and base of tongue cancer (TSCC and BOTSCC) dominate. Furthermore, patients with HPV-positive TSCC and BOTSCC, had a much better clinical outcome than those with corresponding HPV-negative cancer and other head and neck cancer. More specifically, survival was around 80% for HPV-positive TSCC and BOTSCC vs. 40% five-year disease free survival, for the corresponding HPV-negative tumors with conventional radiotherapy and surgery, while this could not be observed for HPV-positive OSCC at other sites. In addition, the past 20-40 years in many Western Countries, the incidence of HPV-positive TSCC and BOTSCC has risen, and >70% are men. This has resulted in a relative increase of patients with HPV-positive TSCC and BOTSCC that may not need the intensified chemo-radiotherapy (with many more severe debilitating side effects) often given today to patients with head and neck cancer. However, before tapering therapy, one needs to enable selection of patients for such treatment, by identifying clinical and molecular markers that together with HPV-positive status will better predict patient prognosis and response to therapy. To conclude, there is a new increasing group of patients with HPV-positive TSCC and BOTSCC with good clinical outcome, where options for better-tailored therapy are needed. For prevention, it would be of benefit to vaccinate both girls and boys against HPV16 infection. For potential future screening the ways to do so need optimizing.

Attitudes toward Human Papilloma Virus Vaccination and Head and Neck Cancer Prevention in a Diverse, Urban Population

OBJECTIVE

(1) To understand if awareness of the human papilloma virus (HPV) vaccination's potential to prevent head and neck cancer improves acceptability of the vaccine in a large urban population and (2) to identify characteristics of those in whom such discussions would have the greatest impact.

STUDY DESIGN

In-person, anonymous survey.

SETTING

Academic public hospital between March 2014 and June 2014.

SUBJECTS

Patients aged 12 to 24 years and their parents or guardians awaiting scheduled outpatient pediatric appointments.

METHODS

Demographics and modified Carolina HPV Immunization Attitudes and Beliefs Scales data were cross-analyzed, followed by univariate binomial logistic regression to identify predictors for major outcomes of interest.

RESULTS

More than 78% of those surveyed indicated they would be more receptive to the HPV vaccine if given strong evidence that it prevented head and neck cancer. Respondents were more likely to increase receptivity to HPV vaccination if they held the belief that they did not have enough information about the vaccine or indicated they preferred to wait because the vaccine was too new.

CONCLUSION

Increasing public awareness of head and neck cancer prevention with HPV vaccination could increase HPV vaccination acceptance.

Genomic landscape of human papillomavirus-associated cancers

Recent next-generation sequencing studies have generated a comprehensive overview of the genomic landscape of human papillomavirus (HPV)-associated cancers. This review summarizes these findings to provide insight into the tumor biology of these cancers and potential therapeutic opportunities for HPV-driven malignancies. In addition to the tumorigenic properties of the HPV oncoproteins, integration of HPV DNA into the host genome is suggested to be a driver of the neoplastic process. Integration may confer a growth and survival advantage via enhanced expression of viral oncoproteins, alteration of critical cellular genes, and changes in global promoter methylation and transcription. Alteration of cellular genes may lead to loss of function of tumor suppressor genes, enhanced oncogene expression, loss of function of DNA repair genes, or other vital cellular functions. Recurrent integrations in RAD51B, NR4A2, and TP63, leading to aberrant forms of these proteins, are observed in both HPV-positive head and neck squamous cell carcinoma (HNSCC) and cervical carcinoma. Additional genomic alterations, independent of integration events, include recurrent PIK3CA mutations (and aberrations in other members of the PI3K pathway), alterations in receptor tyrosine kinases (primarily FGFR2 and FGFR3 in HPV-positive HNSCC, and ERBB2 in cervical squamous cell carcinoma), and genes in pathways related to squamous cell differentiation and immune responses. A number of the alterations identified are potentially targetable, which may lead to advances in the treatment of HPV-associated cancers.

Sexual behavior, HPV knowledge, and association with head and neck cancer among a high-risk group

OBJECTIVES

To understand knowledge of HPV, its association with head and neck cancer (HNC), and source of knowledge in a high-risk population.

MATERIALS AND METHODS

A cross-sectional survey was conducted among attendees at a Drag Racing event in East St. Louis in 2013.

RESULTS

Only 29.9% knew that HPV definitely increases the risk of developing HNC, 42.4% thought HPV was same as HIV, and only 25.1% received HPV information from a healthcare practitioner. Participants that thought number of sexual partners did not increase risk of developing HPV were more likely to have low knowledge scores (r=.74, p<.001). There were significant associations between HNC knowledge, number of sexual partners, age at initial coitus, and risk perception; and those who did not think having more sexual partner increases the chance of developing HPV infection were 33times more likely to have lower knowledge of the association between HPV and HNC (OR=33.27; 95% CI: 16.34, 67.74).

CONCLUSIONS

Knowledge of HPV and its association with head and neck cancer has significant gaps in this population, with a large number of the population accessing HPV information from sources other than a healthcare provider.

Current trends in the etiology and diagnosis of HPV-related head and neck cancers

Human papilloma virus (HPV) infection is a major risk factor for a distinct subset of head and neck squamous cell carcinoma (HNSCC). The current review summarizes the epidemiology of HNSCC and the disease burden, the infectious cycle of HPV, the roles of viral oncoproteins, E6 and E7, and the downstream cellular events that lead to malignant transformation. Current techniques for the clinical diagnosis of HPV-associated HNSCC will also be discussed, that is, the detection of HPV DNA, RNA, and the HPV surrogate marker, p16 in tumor tissues, as well as HPV-specific antibodies in serum. Such methods do not allow for the early detection of HPV-associated HNSCC and most cases are at an advanced stage upon diagnosis. Novel noninvasive approaches using oral fluid, a clinically relevant biological fluid, allow for the detection of HPV and cellular alterations in infected cells, which may aid in the early detection and HPV-typing of HNSCC tumors. Noninvasive diagnostic methods will enable early detection and intervention, leading to a significant reduction in mortality and morbidity associated with HNSCC.

A longitudinal study of human papillomavirus 16 L1, e6, and e7 seropositivity and oral human papillomavirus 16 infection

BACKGROUND

Individuals with human papillomavirus (HPV) infections can develop IgG antibodies to HPV proteins including the L1 capsid and E6 and E7 oncoproteins. Evidence on whether L1 antibodies reduce the risk of cervical HPV infection is mixed, but this has not been explored for oral HPV infections. Antibodies to HPV16's E6 oncoprotein have been detected in some oropharyngeal cancer cases years before cancer diagnosis, but it is unknown if these antibodies are associated with oral HPV16 DNA.

METHODS

Enzyme-linked immunosorbent assays tested for serum antibodies to HPV16's L1 capsid in 463 HIV-infected and 293 HIV-uninfected adults, and for antibodies to recombinantly expressed E6 and E7 oncoproteins to HPV16 in 195 HIV-infected and 69 HIV-uninfected cancer-free participants at baseline. Oral rinse samples were collected semiannually for up to 3 years and tested for HPV DNA using PGMY 09/11 primers. Adjusted Poisson, logistic, and Wei-Lin-Weissfeld regression models were used.

RESULTS

Human papillomavirus 16 L1 seroreactivity did not reduce the subsequent risk of incident oral HPV16 infection in unadjusted (hazard ratio, 1.4; 95% confidence interval, 0.59-3.3) or adjusted (adjusted hazard ratio = 1.1; 95% confidence interval, 0.41-3.0) analysis. Antibodies to HPV16 E6 and E7 oncoproteins were detected in 7.6% and 3.4% of participants, respectively, but they were not associated with baseline oral HPV16 DNA prevalence or oral HPV16 persistence (each P > 0.40).

CONCLUSIONS

Naturally acquired HPV16 L1 antibodies did not reduce the risk of subsequent oral HPV16 infection. Human papillomavirus 16 E6 and E7 seropositivity was not a marker for oral HPV16 infection in this population without HPV-related cancer.

Immunoprevention of human papillomavirus-associated malignancies

Persistent infection by one of 15 high-risk human papillomavirus (hrHPV) types is a necessary but not sufficient cause of 5% of all human cancers. This provides a remarkable opportunity for cancer prevention via immunization. Since Harald zur Hausen's pioneering identification of hrHPV types 16 and 18, found in approximately 50% and 20% of cervical cancers, respectively, two prophylactic HPV vaccines containing virus-like particles (VLP) of each genotype have been widely licensed. These vaccines are beginning to affect infection and HPV-associated neoplasia rates after immunization campaigns in adolescents. Here, we review recent progress and opportunities to better prevent HPV-associated cancers, including broadening immune protection to cover all hrHPV types, reducing the cost of HPV vaccines especially for developing countries that have the highest rates of cervical cancer, and immune-based treatment of established HPV infections. Screening based upon George Papanicolaou's cervical cytology testing, and more recently detection of hrHPV DNA/RNA, followed by ablative treatment of high-grade cervical intraepithelial neoplasia (CIN2/3) have substantially reduced cervical cancer rates, and we examine their interplay with immune-based modalities for the prevention and eventual elimination of cervical cancer and other HPV-related malignancies.

Novel treatments for head and neck squamous cell carcinoma: preclinical identification and clinical investigation

Head and neck squamous cell carcinoma (HNSCC) is a common cancer worldwide. Classically, it is a disease related to tobacco and alcohol use; an increasing number of patients are being diagnosed with HNSCC caused by infection with the human papillomavirus. New deep-sequencing techniques have confirmed the importance of p53 and EGF receptor in HNSCC development, and have identified pathways of critical importance, such as PI3K/mTOR and NOTCH. Increasing knowledge of key molecular features has lead to new therapeutic avenues for HNSCC. Novel therapies under investigation in HNSCC include antibody and small molecule inhibitors of EGF receptor and its family members, PI3K inhibitors, antiangiogenic agents, immunotherapies and agents interacting with early developmental pathways such as Hedgehog.

Long-term persistence of oral human papillomavirus type 16: the HPV Infection in Men (HIM) study

Persistent infection with oral HPV16 is believed to drive the development of most oropharyngeal cancers. However, patterns of oral HPV16 persistence remain understudied, particularly among HIV-negative individuals. Oral HPV16 persistence was evaluated among 1,626 participants of the HPV Infection in Men (HIM) Study. Twenty-three oral HPV16-positive men who provided an oral gargle sample on ≥2 study visits were included in the analysis. Archived oral samples from all follow-up visits were tested for HPV16 using Linear Array and INNO-LiPA detection methods. Persistence was evaluated using consecutive HPV16-positive visits held approximately 6 months apart and using the Kaplan-Meier method. Oral HPV16-positive men were aged 18 to 64 years [median, 36 years; interquartile range (IQR), 25-42] and were followed for a median of 44.4 months (IQR, 29.9-49.5). Of 13 incident infections, 4 (30.8%) persisted ≥12 months, 1 (10.0%) persisted ≥24 months, and none persisted ≥36 months [median infection duration, 7.3 months; 95% confidence interval (CI), 6.4-NA)]. Of 10 prevalent infections, 9 (90.0%) persisted ≥12 months, 8 (80.0%) persisted ≥24 months, 4 (57.1%) persisted ≥36 months, and 2 (40.0%) persisted ≥48 months (median infection duration, NA). Twelve-month persistence of incident infections increased significantly with age (Ptrend = 0.028). Prevalent oral HPV16 infections in men persisted longer than newly acquired infections, and persistence appeared to increase with age. These findings may explain the high prevalence of oral HPV observed at older ages. Understanding oral HPV16 persistence will aid in the identification of men at high-risk of developing HPV-related oropharyngeal cancer.

Human papilloma virus vaccination: impact and recommendations across the world

Human papilloma virus (HPV) vaccination has been implemented in several countries for about the past 7 years, mainly in the adolescent female population, with varying coverage results. Although the impact of immunization on cervical and other HPV-related cancers will be evident in the next decades, a marked decrease of prevalent HPV infections, precancerous lesions and genital warts is already dramatic in the vaccinated cohorts, and also in their sexual partners, thus providing clear evidence of the effectiveness of HPV vaccination, including a herd-protection effect. Today, recommendations and implementation of universal HPV vaccination for adolescent girls are a public-health priority in all countries of the world. Countries with limited resources are presently involved in demonstration projects and, in some cases, have launched national programmes with the help of international agencies and alliances. Extension of immunization offer to young women and to adolescent male subjects has become an important additional opportunity for several countries, with a special focus needed on homosexual men with HIV infection who are at particularly increased risk of HPV-related diseases. Public-health authorities are confronted with the need to enlarge HPV-vaccination offer to all target groups, especially pre-adolescent girls, so that they can be saved from dreadful cancers by reaching high immunization coverage.

The role of sexual behavior in head and neck cancer: implications for prevention and therapy

HPV-positive oropharyngeal squamous cell carcinoma (HPV-OSCC) is associated with oral sexual behaviors. The sharp rise in incidence of HPV-OSCC in the USA has been attributed to changes in sexual norms over the past five decades, with lower age at sexual debut and higher numbers of sexual partners per individual. In addition, variations in HPV-OSCC prevalence by race, age cohort and gender may be attributable to differences in oral sexual behaviors among these groups. Oral HPV infection is the putative precursor to HPV-OSCC. Risk factors for oral HPV incidence, prevalence, clearance and persistence are crucial to understanding how, and in whom, oral HPV infection progresses to malignancy. Future investigation should focus on elucidating the natural history of oral HPV infection persistence and malignant transformation, developing effective screening tools and exploring opportunities for prevention such as vaccination and public health education.

Comparison of expected health impacts for major cancers: integration of incidence rate and loss of quality-adjusted life expectancy

PURPOSE

The study aims to quantify the expected impacts of different cancers through multiplying the incidence rate by loss-of-QALE (quality-adjusted life expectancy), with QALY (quality-adjusted life year) as the common unit, to aid prevention policy decisions.

METHODS

464,722 patients with pathologically verified cancer registered in the Taiwan Cancer Registry during 1998-2009 were used to estimate lifetime survival through Kaplan-Meier estimation combined with a semi-parametric method. A convenience sample for measuring the utility value with EQ-5D was conducted with 11,453 cancer patients, with the results then multiplied by the survival functions to estimate QALE. The loss-of-QALE was calculated by subtracting the QALE of each cancer cohort from the life expectancy of the corresponding age- and gender-matched reference population. The cumulative incidence rates from age 20 to 79 (CIR₂₀₋₇₉) were calculated to estimate the lifetime risk of cancer for each organ-system.

RESULTS

Liver and lung cancer were found the highest expected lifetime health impacts in males and females, or expected lifetime losses of 0.97 and 0.41 QALYs that could be averted, respectively. While the priority changes for prevention based on expected health impacts were slightly different for females based on standardized mortality rates, those of males involve a broader spectrum, including oral, colorectal, esophageal and stomach cancer.

CONCLUSION

The integration of incidence rate with loss-of-QALE could be used to represent the expected losses that could be averted by prevention, which may be useful in prioritizing strategies for cancer control.

Reduced prevalence of vulvar HPV16/18 infection among women who received the HPV16/18 bivalent vaccine: a nested analysis within the Costa Rica Vaccine Trial

BACKGROUND

Vaccine efficacy (VE) against vulvar human papillomavirus (HPV) infection has not been reported and data regarding its epidemiology are sparse.

METHODS

Women (n = 5404) age 22-29 present at the 4-year study visit of the Costa Rica Vaccine Trial provided vulvar and cervical samples. A subset (n = 1044) was tested for HPV DNA (SPF10/LiPA25 version 1). VE against 1-time detection of vulvar HPV16/18 among HPV vaccinated versus unvaccinated women was calculated and compared to the cervix. Prevalence of and risk factors for HPV were evaluated in the control arm (n = 536).

RESULTS

Vulvar HPV16/18 VE (54.1%; 95% confidence interval [CI], 4.9%-79.1%) was comparable to cervix (45.8%; 95% CI, 6.4%-69.4%). Vulvar and cervical HPV16 prevalence within the control arm was 3.0% and 4.7%, respectively. Independent risk factors for vulvar HPV were similar to cervix and included: age (adjusted odds ratio [aOR] 0.5 [95% CI, .3-.9] ≥28 vs 22-23]); marital status (aOR 2.3 [95% CI, 1.5-3.5] single vs married/living-as-married); and number of sexual partners (aOR 3.6 [95% CI, 1.9-7.0] ≥6 vs 1).

CONCLUSIONS

In this intention-to-treat analysis, VE against vulvar and cervical HPV16/18 were comparable 4 years following vaccination. Risk factors for HPV were similar by anatomic site.

CLINICAL TRIALS REGISTRATION

NCT00128661.

Human papillomavirus prevalence in oropharyngeal cancer before vaccine introduction, United States

We conducted a study to determine prevalence of HPV types in oropharyngeal cancers in the United States and establish a prevaccine baseline for monitoring the impact of vaccination. HPV DNA was extracted from tumor tissue samples from patients in whom cancer was diagnosed during 1995–2005. The samples were obtained from cancer registries and Residual Tissue Repository Program sites in the United States. HPV was detected and typed by using PCR reverse line blot assays. Among 557 invasive oropharyngeal squamous cell carcinomas, 72% were positive for HPV and 62% for vaccine types HPV16 or 18. Prevalence of HPV-16/18 was lower in women (53%) than in men (66%), and lower in non-Hispanic Black patients (31%) than in other racial/ethnic groups (68%–80%). Results indicate that vaccines could prevent most oropharyngeal cancers in the United States, but their effect may vary by demographic variables.

Invited commentary: multiple human papillomavirus infections and type replacement-anticipating the future after human papillomavirus vaccination

Prophylactic human papillomavirus (HPV) vaccination with 3 doses of either of 2 commercially available vaccines is highly efficacious in preventing infections with the most carcinogenic types of HPV (HPV 16 and HPV 18) at the cervix and other anatomical sites at which HPV-related cancers develop. Concern has been raised that eradicating the most virulent HPV types, 16 and 18, could result in 1 or more of the types that are not targeted by the vaccine occupying the ecological niche created by the elimination of these types, referred to as type replacement. In this issue of the Journal, Yang et al. (Am J Epidemiol. 2014;180(11):1066-1075) report on concurrent infections with multiple HPV types in unvaccinated women who underwent cervical screening in New Mexico (December 2007-April 2009) to identify possible interactions between HPV types, which if present could suggest the possibility of type replacement. Consistent with previous reports, they show minimal type-specific interactions among women with normal cytology, which they consider an indication that type replacement of HPV 16/18 is unlikely to be an issue in the general population postvaccination. Type replacement may be of less concern with the introduction of multivalent vaccines that include most of the carcinogenic HPV types; continued surveillance postvaccination should improve our understanding of the impact of HPV vaccination on type distribution and screening performance.

Change in population prevalences of human papillomavirus after initiation of vaccination: the high-throughput HPV monitoring study

BACKGROUND

Organized human papillomavirus (HPV) vaccination was introduced in Sweden in 2012. On-demand vaccination was in effect from 2006 to 2011. We followed the HPV prevalences in Southern Sweden from 2008 to 2013.

METHODS

Consecutive, anonymized samples from the Chlamydia trachomatis screening were analyzed for HPV DNA for two low-risk types and 14 high-risk types using PCR with genotyping using mass spectrometry. We analyzed 44,146 samples in 2008, 5,224 in 2012, and 5,815 in 2013.

RESULTS

Registry-determined HPV vaccination coverages of the population in Southern Sweden increased mainly among 13- to 22-year-old women. Most analyzed samples contained genital swabs from women and the HPV6 prevalence in these samples decreased from 7.0% in 2008 to 4.2% in 2013 [-40.0%; P < 0.0005 (χ(2) test)]. HPV16 decreased from 14.9% to 8.7% (-41.6%; P < 0.0005) and HPV18 decreased from 7.9% to 4.3% (-45.6%; P < 0.0005) among 13- to 22-year-old women. There were only small changes in vaccination coverage among 23- to 40-year-old women. In this age group, HPV18 decreased marginally (-19.6%; P = 0.04) and there were no significant changes for HPV6 or HPV16. Two nonvaccine HPV types (HPV52 and HPV56) were increased among 13- to 22-year-old women, both in 2012 and 2013.

CONCLUSIONS

A major reduction of HPV6, 16, and 18 prevalences is seen in the age groups with a concomitant increase in HPV vaccination coverage. The minor changes seen for nonvaccine types will require further investigation.

IMPACT

Monitoring of type-specific HPV prevalences may detect early effects of HPV vaccination.

Oral human papillomavirus (HPV) prevalence in youth and cervical HPV prevalence in women attending a youth clinic in Sweden, a follow up-study 2013-2014 after gradual introduction of public HPV vaccination

During 2009-2011, we reported that the oral and cervical prevalence of human papillomavirus (HPV) was high by international standards at 9.3% and 74%, respectively, in youth aged 15-23 years attending a youth clinic in Stockholm. After gradual introduction of public HPV vaccination during 2007-2012, between 2013 and 2014, when 73% of the women were HPV-vaccinated, but not necessarily before their sexual debut, oral HPV prevalence had dropped to 1.4% as compared with 9.3% in 2009-2011 (p < 0.00001). Cervical HPV prevalence was high and common cervical high-risk types were HPV51, 56, 59, 73, 16, 39, 52, and 53. However, it was shown that HPV16, 31, and 70 were significantly less common among HPV-vaccinated women than among those who had not received the vaccine.

Incidence of human papillomavirus positive tonsillar and base of tongue carcinoma: a stabilisation of an epidemic of viral induced carcinoma?

AIM

To investigate whether the rise during the past decades in the incidence of tonsillar and base of tongue squamous cell carcinoma (TSCC and BOTSCC) and the proportion of human papillomavirus (HPV) positive cancer has continued in Stockholm.

PATIENTS AND METHODS

Pre-treatment biopsies (n=252) available from 280 patients diagnosed with TSCC and BOTSCC during 2008-2012 in the County of Stockholm were tested for HPV DNA by a multiplex bead-based assay. Incidence records were acquired from the Swedish Cancer Registry. The data obtained were evaluated together with previous figures from 1970 to 2007.

RESULTS

HPV DNA was present in 186/252 (74%) of TSCC and BOTSCC biopsies obtained during 2008-2012 in Stockholm. In this region the age-standardised incidence, including the prevalence of HPV-positive and HPV-negative TSCC stabilised 2007-2012 compared to 2000-2006, while for BOTSCC throughout 1998-2012 the same parameters increased moderately (p<0.05, for all). In parallel, from 2000 to 2006 through 2007-2012 in Sweden, the age-standardised incidence of both TSCC and BOTSCC continued to rise (p=0.012 and p=0.001 respectively).

CONCLUSION

During 2000-2012 the age-standardised incidence and the proportion of HPV-positive TSCC have stabilised at a high level, while the proportion of HPV-negative cancer has remained at a low level in Stockholm, whereas for BOTSCC all parameters are increasing moderately. In contrast, in Sweden the incidence of both TSCC and BOTSCC is still increasing. We hypothesise that the HPV epidemic could be stabilising, first for TSCC, but so far not for BOTSCC, in e.g. some urban areas, while previous trends for both tumours persist at other geographic locations.

Oral and oropharyngeal cancer

Oral and oropharyngeal cancer (OPC) is a complex and often relentless malignancy prone to local invasion and dissemination. Despite advances in understanding of the disease and improved therapeutic interventions, it continues to be diagnosed at an advanced stage and the survival rate remains poor. The financial cost of treating OPC may be the highest of all cancers in the United States and survivors often experience major detriments to quality of life. Major risk factors for OPC are tobacco, alcohol, areca nut, and human papillomavirus infection. This article updates medical practitioners on the causes, presentation, diagnosis, and management of OPC.

HPV DNA, E6/E7 mRNA, and p16INK4a detection in head and neck cancers: a systematic review and meta-analysis

BACKGROUND

We aimed to provide updated information about the global estimates of attributable fraction and type distribution of human papillomavirus (HPV) in head and neck squamous cell carcinomas by doing a systematic review and meta-analysis.

METHODS

We did a literature search on PubMed to identify studies that used PCR for detection of HPV DNA in head and neck squamous cell carcinomas with information about HPV genotype distribution. We included studies that tested 20 or more biopsies per cancer site and were published between July 15, 1990, and Feb 29, 2012. We collected information about sex, risk factors, HPV detection methods, and biomarkers of potentially HPV-induced carcinogenesis (E6/E7 mRNA and p16(INK4a)). If it was not possible to abstract the required information directly from the paper, we contacted the authors. We did a meta-analysis to produce pooled prevalence estimates including a meta-regression to explore sources of heterogeneity.

FINDINGS

148 studies were included, contributing data for 12 163 cases of head and neck squamous cell carcinoma from 44 countries. HPV DNA was detected in 3837 cases. HPV16 accounted for 82·2% (95% CI 77·7-86·4) of all HPV DNA positive cases. By cancer site, pooled HPV DNA prevalence estimates were 45·8% (95% CI 38·9-52·9) for oropharynx, 22·1% (16·4-28·3) for larynx (including hypopharynx), and 24·2% (18·7-30·2) for oral cavity. The percent positivity of p16(INK4a) positive cases in HPV-positive oropharyngeal cancer cases was 86·7% (95% CI 79·2-92·9) and of E6/E7 mRNA positive cases was 86·9% (73·2-96·8). The estimate of HPV attributable fraction in oropharyngeal cancer defined by expression of positive cases of E6/E7 mRNA was 39·8% and of p16(INK4a) was 39·7%. Of subsites, tonsils (53·9%, 95% CI 46·4-61·3) had the highest HPV DNA prevalence. HPV DNA prevalence varied significantly by anatomical site, geographic region, but not by sex or tobacco or alcohol consumption.

INTERPRETATION

The contribution of HPV prevalence in head and neck squamous cell carcinoma and in particular that of HPV16 in the oropharynx shows the potential benefit of prophylactic vaccines.

FUNDING

European Commission.

Human papillomavirus vaccines: key factors in planning cost-effective vaccination programs

Prophylactic HPV vaccines hold tremendous potential for reducing cervical and non-cervical HPV-related disease burden worldwide. To maximize on this potential, policy officials will need to carefully consider available evidence, existing uncertainties and the cost-effectiveness of mass HPV vaccination programs in the context of their respective nations and/or regions. Proper harmonization of primary prevention strategies with secondary prevention efforts will also be important. Decisions following such considerations may ultimately depend on programmatic objectives, infrastructure and available resources. Continued research and surveillance surrounding HPV vaccination will be essential for filling current knowledge gaps, and forcing ongoing reconsiderations of selected immunization strategies.

Detection of human papillomavirus in the oral cavities of persons with Fanconi anemia

OBJECTIVE

We conducted a cross-sectional study to describe the prevalence and correlates of type-specific human papillomavirus (HPV) DNA in the oral cavities of persons with Fanconi anemia.

MATERIALS AND METHODS

Oral swabs were collected from 67 participants with Fanconi anemia and tested for 27 HPV genotypes using polymerase chain reaction-based methods.

RESULTS

Participants were a mean of 18.6 (standard deviation, 10.0) years of age (range 4-47 years). The prevalence of oral HPV infection was 7.5%, and the prevalence of high-risk HPV infection was 6.0%. HPV type 16 was not detected in any samples. Prevalence was higher in adults than in children (13.3% vs 2.7% in those ≥18 vs <18 years of age). Among adults, prevalence was higher in males than in females (25.0% vs 9.1%, respectively).

CONCLUSIONS

Prevalence of oral HPV infection in persons with Fanconi anemia was comparable to estimates from other studies in the general population. However, in contrast to previous studies, we did not identify HPV type 16 (the type found in most HPV-related head and neck cancers) in any participants.

Adolescent sexual activity and cancer risk: physicians' duty to inform?

Yearly, 33,000 cancer diagnoses in the US are attributed to human papillomavirus (HPV), with cervical cancer the most common. HPV is transmitted through sexual contact; HPV types 16 and 18 cause the majority of ano-genital cancers in men and women. HPV causes ∼100% of cervical cancers, ∼90% of anal cancers, and ∼50% of vaginal, vulvar, and penile cancers. HPV is also involved in ∼70% of oropharyngeal cancers (OPCs) in the US. The CDC recommends routine administration to all female (bivalent or quadrivalent vaccine) and male (quadrivalent vaccine) patients at 11-12 years of age; the series may be started as early as 9 years of age. Recent evidence suggests physicians do not universally recommend the vaccine to all adolescents. Additionally, parents may refuse the vaccine due to safety concerns as well as religious and moral beliefs related to onset of sexual debut. It has been suggested physicians should consider discussing HPV vaccine as a cancer prevention tool only, with less focus on the fact that transmission is caused by sexual activity. In this commentary we suggest physicians have a duty to warn parents and adolescents that OPCs may be transmitted through oral sex, which is often perceived as not constituting sexual activity.

Prevalence of tonsillar human papillomavirus infections in Denmark

The incidence of tonsillar carcinomas associated with Human Papillomavirus (HPV) infection has increased dramatically over the last three decades. In fact, currently in Scandinavia, HPV-associated cases account for over 80 % of tonsillar carcinoma cases. Yet, the epidemiology and natural history of tonsillar HPV infections remains poorly characterized. Our aim was to characterize such infections in the Danish population in tumor-free tonsillar tissue. Unlike previous studies, we considered both palatine tonsils. We examined both tonsils from 80 patients with peritonsillar abscess (n = 25) or chronic tonsillar disease (n = 55). HPV was detected by nested PCR with PGMY 09/11 and GP5+/GP6+L1 consensus primers, and typed by sequencing. Samples were also analyzed using a higher-throughput method, the CLART HPV 2 Clinical Array Assay. The overall prevalence of HPV tonsillar infection was 1.25 % (1/80, 95 % CI 0.03-6.77 %) by nested PCR, and 0 % by CLART HPV2 Clinical Array. The HPV-positive patient was a 16-year-old female with recurrent tonsillitis and tonsillar hypertrophy. The type detected was HPV6. HPV was not detected in the contralateral tonsil of this patient. Compared to cervical HPV infections in Denmark, tonsillar HPV infections are 10- to 15-fold less frequent. In the HPV-positive patient in this study, HPV was detected in only one of the tonsils. This raises the possibility that prior studies may underestimate the prevalence of HPV infections, as they do not consider both palatine tonsils.

Human Papillomavirus and Oropharyngeal Squamous Cell Carcinoma of the Head and Neck: A Growing Epidemic

Human papillomavirus (HPV) is now considered a major causative agent in oropharyngeal squamous cell carcinoma (OP-SCC). The incidence of HPV+ OP-SCC is increasing dramatically, is higher in men, and is now more common than cervical cancer in the United States. HPV+ OPSCCs usually present as locally advanced, stage IV cancers, requiring intensive treatment with surgery, chemotherapy, and/or radiation that can cause tremendous morbidity. HPV vaccination is predicted to prevent HPV+ OP-SCC because over 90% are caused by vaccine-type HPV. However, current vaccination rates are not yet high enough to be effective at preventing HPV-associated malignancies at a population level.