Differences in history of sexual behavior between patients with oropharyngeal squamous cell carcinoma and patients with squamous cell carcinoma at other head and neck sites

Low risk of second primary malignancies among never smokers with human papillomavirus-associated index oropharyngeal cancers

BACKGROUND

Among patients with index oropharyngeal cancer, second primary malignancies (SPMs) may be less common in cases of human papillomavirus (HPV)-associated tumors than HPV-negative tumors. Further modification of these SPM risks by smoking has not been reported.

METHODS

SPM outcomes of 356 patients with incident oropharyngeal cancer were analyzed using Cox proportional hazards and Kaplan-Meier models. SPM risk and SPM-free survival were compared in HPV-seronegative patients, HPV-seropositive never smokers, and HPV-seropositive ever smokers.

RESULTS

HPV-seropositive patients had a lower 5-year SPM rate than HPV-seronegative patients (5.6% vs 14.6%; p = .051). Compared to HPV-seronegative patients, HPV-seropositive never smokers had a 73% reduced SPM risk, and HPV-seropositive ever smokers had a 27% reduced SPM risk (trend p = .028). Although HPV-seronegative patients had SPMs in traditional locations, 70% of SPMs among HPV-seropositive patients were outside typical tobacco-related sites.

CONCLUSION

HPV serologic status and smoking may stratify patients with index oropharyngeal cancers in terms of risk and location of SPMs.

Genetic variants of NOXA and MCL1 modify the risk of HPV16-associated squamous cell carcinoma of the head and neck

Abstracts

The connection between human papillomavirus and oropharyngeal squamous cell carcinomas in the United States: implications for dentistry

BACKGROUND

Results from studies conducted in the past several years suggest that some oropharyngeal cancers, those of the base of the tongue and the tonsils, are associated with high-risk types of human papillomavirus (HPV). In this article, the authors summarize the available evidence regarding the epidemiology of HPV-associated oropharyngeal cancers in the United States, the available HPV vaccines and the implications of these for dentistry. They also examine the differences in HPV prevalence between cancers of the oral cavity and those of the oropharynx.

TYPES OF STUDIES REVIEWED

The authors searched PubMed, Web of Science, The Cochrane Library and the National Guideline Clearinghouse to identify English-language systematic reviews and meta-analyses focused on HPV-associated oropharyngeal squamous cell cancers published from January 2005 through May 2011.

RESULTS

Molecular and epidemiologic evidence suggest a strong etiologic association of HPV with oropharyngeal cancers. The incidence of oropharyngeal cancers in the United States has increased between 1973 and 2007, whereas that of cancers at other head and neck sites has decreased steadily. Compared with HPV-negative cancers, HPV-positive oropharyngeal cancers are associated with certain sexual behaviors, occur more often among white men and people who do not use tobacco or alcohol, and may occur in a population younger by about four years (median ages, 52-56 years). Despite often having a later stage of diagnosis, people with HPV-positive oropharyngeal cancers have a lower risk of dying or recurrence than do those with HPV-negative cancers. The effectiveness of the HPV vaccine in preventing oropharyngeal cancers is unknown.

CLINICAL IMPLICATIONS

Dental health care personnel (DHCP) should be knowledgeable about the role of HPV in carcinogenesis, the association of HPV with oropharyngeal cancers and HPV vaccines, and they should be prompt in referring patients with suggestive symptoms for evaluation. DHCP can play an important role in increasing patients' knowledge about HPV and oropharyngeal cancers.

Genetic variants of a BH3-only pro-apoptotic gene, PUMA, and risk of HPV16-associated squamous cell carcinoma of the head and neck

P53 up-regulated modulator of apoptosis (PUMA) is a critical factor in the intrinsic apoptotic pathway. Through PUMA-dependent mechanisms, human papillomavirus 16 (HPV16) oncoprotein may affect apoptosis by E6-mediated p53 degradation. To examine whether the PUMA variants modify the association between HPV16 serology and risk of squamous cell carcinoma of the head and neck (SCCHN), we genotyped two polymorphisms in the PUMA promoter (rs3810294 and rs2032809) in 380 cases and 335 cancer-free controls of non-Hispanic Whites, who were frequency-matched by age (±5 yr), sex, smoking, and drinking status. We found that each individual polymorphism had only a modest impact on risk of SCCHN, particularly in oropharyngeal cancer for rs3810294 and non-oropharyngeal cancer for rs2032809. After we stratified the individuals by HPV16 serology, and used those with the corresponding common homozygous genotype and HPV16 seronegativity as the reference group, for each polymorphism we found that the risk of SCCHN associated with HPV16 seropositivity was higher among those with variant genotypes than those with the corresponding common homozygous genotype. Notably, this effect modification was particularly pronounced in several subgroups including never smokers, never drinkers, younger patients, and patients with oropharyngeal cancer. Furthermore, we also characterized the functional relevance of the two polymorphisms to explore the genotype-phenotype correlation. Our results suggested that the PUMA promoter polymorphisms may be a biomarker for risk of HPV16-associated SCCHN, particularly in never smokers, never drinkers, younger patients, and patients with oropharyngeal cancer. Larger studies are needed to validate our findings.

[Evolution of sexual behaviour in France and emergence of new head and neck cancers]

Despite the decreasing incidence of head and neck cancers, the incidence of oropharyngeal cancers related to HPV is increasing. New risk factors, other than tobacco or alcohol consumption, were described, such as sexual behaviours. The objective of this synthesis was to compare sexual behaviours described in three French studies conducted in 1970, 1992 and 2006 to other studies published in the international literature in order to assess if sexual behaviours could explain the emergence of these new oropharyngeal cancers. We globally found that the diversification of sexual behaviours (e.g., increase of the mean number of sexual partners and of oral sex practices) and the increase of specific head and neck HPV-positive cancers evolved in the same way. Even if the causality between head and neck cancers, HPV and sexual behaviours has not been clearly established, this hypothesis has to be discussed.

Ancillary studies in determining human papillomavirus status of squamous cell carcinoma of the oropharynx: a review

Squamous cell carcinoma (SCC) of the oral cavity and pharynx represents the sixth most common form of malignancy worldwide. A significant proportion of these cases are related to human papillomavirus (HPV) infection. In general, HPV-associated SCC is more commonly nonkeratinizing and poorly differentiated, whereas non-HPV-associated SCC is typically keratinizing and moderately differentiated. Nevertheless, significant overlap in morphology is seen between these two forms of SCC. The purpose of this paper is to highlight the utility of ancillary studies in the establishment of HPV status of oropharyngeal SCC, including p16 immunohistochemistry, high-risk HPV in situ hybridization, polymerase chain reaction, and newer HPV detection modalities.