Approaching the topic of orogenital transmission of human papillomavirus (HPV) with a woman presenting with a persistent cervicovaginal HPV infection is more problematic than it may seem. To not mention it, however, would be to pass over an opportunity to prevent oropharyngeal cancer. There are no clear indications from any scientific authorities as to how a doctor should broach the subject, and therefore it comes down to the individual to weigh the ethical implications of counseling. In a highly detailed article, a group of Italian clinicians describes what they know about the orogenital transmission of HPV and raises several points worth reflection.
“In wealthy countries oropharyngeal squamous-cell carcinomas (OPSCC) are now the most frequent HPV-related cancer, having overtaken cervical cancer,” wrote the authors of the article, which was published in the BMC Women’s Health journal. “Orogenital HPV transmission has now overtaken smoking and heavy alcohol consumption as the main risk factor for oropharyngeal cancers.”
Oropharyngeal HPV infection occurs mainly through contact between the mouth and anogenital region. The bidirectional transmission of HPV between the genital and the oral area acts as a promoter of OPSCCs in women and men. “The reason why the risk of persistent oral HPV infection is so much higher in men than in women remains unexplained, as the prevalence of genital HPV infection is comparable in both sexes,” the authors wrote.
The very long incubation period between oral infection and cancer development complicates strategies aimed at early diagnosis of HPV-related OPSCCs. More importantly, no specific precursor lesion has been consistently identified in the oral cavity and oropharynx, as they have been for cervical cancer. Many tumors develop in correspondence with tonsil stones and are therefore hidden from visual inspection, with a low level of reliability of cytological screening from swabbing. On the other hand, a molecular examination from oropharyngeal lavage could reveal an active infection, but not necessarily the presence of a premalignant lesion.
“Until uncertainties on screening and early diagnosis are disentangled, primary prevention remains the only means to successfully counteract the rising incidence of OPSCCs,” wrote the authors. The currently available 9-valent vaccine appears to protect against infection with viral subtypes associated with over 90% and almost 80% of HPV-related cancers of the oropharynx and larynx, respectively. The rate of vaccination is, however, unsatisfactory — especially in young people — as there is a widespread false belief that it only works to prevent cervical cancer.
“Hypothetically, preventive measures could be recommended, modifications in sexual behaviors suggested, and information for future partners considered. However, any modification of the counseling usually provided to women with a positive cervicovaginal HPV test should be based not only on evidence, but also on the actual likelihood of a beneficial effect on the incidence of HPV-associated oropharyngeal cancers, as well as on the potential harms associated with novel recommendations. The risk is, on one side to induce unjustified anxiety and provide ineffective instructions, on the other side to miss the opportunity to limit the spread of oral HPV infections.”
The authors hope, therefore, for major health authorities and international gynecologic scientific societies to issue more detailed recommendations on how women with a persistent high-risk HPV-DNA test should be counseled regarding orogenital sex and the risk of oropharyngeal cancer. “Communicating uncertainties would be also important, but communicating ‘official uncertainties’ is one thing, and communicating personal uncertainties is another thing.”
This article was translated from Univadis Italy.
