Dentistry LIVE speaker and hygienist Jo-Anne Jones reveals how sex and oral health are intrinsically linked
Are sexual relations closely intertwined with oral health? It would appear so with the connection between the human papillomavirus (HPV) and oral cancer emerging as a global pandemic. The same viral strain, HPV-16 that is responsible for 70-80% of all cervical cancers, is solely responsible for 85-95% of all HPV related oropharyngeal cancers (6). If recent incidence trends continue, the annual number of oropharyngeal cancers related to HPV-positive oropharyngeal cancers will surpass annual number of cervical cancers by the year 20207. Among the sites of HPV-associated cancers, the oropharynx is the second most common after the cervix at present.
Oral sex, safer sex?
Why the alarming increase? The conjecture is that this sharp increase is the ‘legacy’ of the sexual revolution. Who’s to say whether it is the sexual revolution of the Sixties or the widely publicised and subsequent redefining of sexual relations by a former US president?
Regardless of the origin, possessing increased awareness will contribute to earlier stage identification of an abnormal oral lesion resulting in improved survival rates. HPV is passed on through genital contact during vaginal and anal sex. HPV may also be passed on during oral sex and genital-to-genital contact. HPV can be passed on between straight and same-sex partners – even when the infected partner has no signs or symptoms. It has also been reported that HPV may be passed on through open-mouthed kissing if the virus is active. A study, which appeared in the New England Journal of Medicine, shows that men and women who reported having six or more oral-sex partners during their lifetime had a nearly nine-fold increased risk of developing cancer of the tonsils or at the base of the tongue.
There are more than 40 HPV types that can infect the genital areas of males and females. Many HPV infections will cause no clinical problems and resolve on their own without treatment. The age-specific prevalence of HPV infection is at its peak between the ages of 20-24. The prevalence of HPV infection tapers off as the population ages. This is largely due to lifestyle behaviours and sexual activity. The strongest behavioural risk for HPV-related oropharyngeal cancer is the lifetime number of oral sex partners.
How do we prevent HPV transmission?
There are a number of ways that people can lower risk of getting HPV. Vaccination may represent the best primary prevention method related to cervical cancer, as condoms have limited efficacy and abstinence is unacceptable to many. The two vaccines that are currently offered are Gardasil and Cervarix. Gardasil is recommended for both genders and provides protection against HPV-6, 11, 16 and 18. This vaccine is available for girls and young women and boys and young men (9) through 26 years of age.
For those who are older and sexually active, condoms may lower the risk of developing HPV-related diseases such as genital warts and cervical cancer. However, HPV can infect areas that are not covered by a condom. Limiting the number of sex partners – and choosing a partner who has had no or few prior sex partners – serve to lower the risk. It is important to note that even people with only one lifetime sex partner can get HPV. Further, it may not be possible to determine if a partner who has been sexually active in the past is currently infected.
Over time, the hope is that the vaccination will dramatically reduce the incidence of cervical cancer in females, thereby lowering the risk of transmission of the virus. This along with any new medical intervention will take years of surveillance data in order to draw conclusive observations and results.
What is the oral manifestation of HPV-related disease?
Generally speaking, the most common anatomical sites for HPV-positive oropharyngeal cancer are the posterior base of the tongue, tonsillar area and the oropharynx. It may occur on the lips and the tongue as well. In the broadest of terms, non-HPV positive tumours tend to involve the anterior tongue, floor of mouth and buccal mucosa.
An oral lesion associated with HPV often contains a number of papillary projections which mimic the surface configuration of a cutaneous wart. Condyloma acuminatum, otherwise known as a venereal wart is caused by HPV-6, 11, 16 and 18. It is sexually transmitted and appears as a papillary nodule attached with a broad base. Microscopic evaluation is always required to establish a definitive diagnosis. It is painless and persistent occurring most often in young adults. Condyloma acuminatum most commonly occurs on the lips, tongue and the soft palate (see Figure 1, below).
Anogenital lesions may also be present. Reinoculation amongst sexual partners is common. Verrucous Carcinoma related to HPV-16 and 18 is painless and incurs continual enlargement. It is also referred to as Snuff Dippers Cancer due to smokeless tobacco being a significant risk factor. It presents clinically with a diffuse, white, papillary or corrugated thickening. If related to smokeless tobacco, Verrucous Carcinoma most often occurs on the mandibular buccal vestibule at the site of the chronic tobacco exposure.
HPV versus non-HPV survival rates
Earlier discovery of an abnormal oral lesion can greatly impact survival rates of this insidious disease. The majority of oral cancer is discovered at the late stage 3 or 4 where occurrence of metatases or lymph node involvement has already taken place. Five-year survival rates are approximately 50% when discovered at the later stage and as high as 90% when discovered earlier.
The good news is that HPV-positive oropharyngeal typically has better survival rates and is more responsive to traditional treatment than non-HPV oropharyngeal cancers. If we compare HPV-positive versus non-HPV oropharyngeal squamous cell carcinoma, there is a better three year survival rate for HPV-positive tumours being 82.4% versus 57.1% among patients with HPV-negative tumours.
HPV-positive oropharyngeal cancer was more common among non-smokers and significantly associated with younger age, white race and smaller primary tumours. The cumulative incidence of second primary tumors was significantly lower among patients with HPV-positive tumours largely because of lower rates of smoking-related cancer (9)
What can we do as dental professionals?
With HPV-positive oropharyngeal cancer often occurring in areas where visual acuity is somewhat restricted, it is imperative to inspect these areas of the mouth to the best of our abilities. Full protrusion of the tongue is critical in order to examine the posterior lateral borders and the dorsum.
Both visual and tactile examination need to be performed in order to discover the earliest presence of an abnormal lesion (see Figures 2 and 3, below)
There are also some subtle warning signs that accompany this virally and sexually transmitted oral cancer. Identifying some of the more subtle symptoms may allow our professional to identify posterior oropharyngeal abnormalities at a much earlier stage.
In conclusion, with the acquired knowledge of risk behaviours and prevention strategies, our profession is strategically positioned to play an integral role in earlier discovery of an abnormal lesion thus contributing strongly to better treatment outcomes, improved survival rates and enhanced quality of life for our dental hygiene clients.
• References available on request
Jo-Anne will be speaking at Dentistry LIVE on both the hygiene & therapy and team tracks. Join her for an open, frank ‘sex talk’ guaranteed to change the way you screen for oral cancer at Dentistry LIVE on the 25-26 May at the QEII Conference Centre. To book tickets for this world-class symposium, call 0800 371 652 or email [email protected]
Jo-Anne Jones is an international speaker inspiring dental audiences to embrace the profession they have chosen with a renewed confidence and enthusiasm. She is the president of RDH CONNECTION Inc., and CEO of Dental Hygiene Studios Inc. Having a career spanning more than three decades, Jo-Anne’s experience has encompassed clinical practice, education, international lectur ing an d is published both nationally and internationally.
Jo-Anne has been appointed to serve on the advisory board for Dentistry Today and joins the 2012 CE Leaders. Jo-Anne has been nominated for a 2012 Dental Excellence Award for the Most Effective Dental Hygiene Educator by her peers.