The research project, recently published in the European Journal of Cancer, examined occurrences of HPV in oropharyngeal cancer patients from Zealand, Bornholm, Greenland and the Faeroe Islands over a period of 18 years.
One of the main results of the study showed that there has been a three-fold increase in oropharyngeal cancer cases caused by HPV from 2000 to 2017.
– We can see that the number of patients with oropharyngeal cancer caused by HPV has increased significantly. We gathered a very large sam-ple that covered half the Danish population, and as we know that there is no difference between the occurrence of head and neck cancer between the two different parts of the country, the results can be interpreted such that the number of oropharyngeal cancer cases caused by HPV have in-creased significantly across Denmark as a whole, said Christian von Buchwald, professor, consultant and head of the research project. He called the increase disturbing:
– Denmark, together with the US, Canada and the other Nordic countries, are high-risk countries for HPV-related tonsil cancer and cancer in the base of the tongue.
The fact that HPV, and not tobacco, is the reason for the large increase is consistent with the fact that the research project also shows that an in-creasing number of non-smokers are being diagnosed with this type of cancer.”
New patient group: New patients are younger and non-smokers
Historically, cancer of the mouth, throat and tonsils has been associated with alcohol and cigarette consumption.
– Previously, it was typically smokers who were diagnosed with oropharyn-geal cancer. This is not the case anymore. We’re seeing an increasing number of non-smoking men become diagnosed with this type of cancer. Patients are also younger and the disease often presents itself as a large swelling on the throat, as the metastasis appears earlier, said Christian Grønhøj, MD and PhD, who recently received the Danish Cancer Society’s Junior Researcher Award 2020 and who is one of the researchers behind the study.
HPV is a sexually transmitted virus contracted during sexual contact of the mucous membranes. If you become infected with carcinogenic HPV, it takes many years, even decades, before the virus becomes cancerous:
– HPV-related cancer of the head and neck has other risk factors than smoking and alcohol related cancer. It is therefore important that we pay greater attention to other lifestyle factors when discussing diagnostics and symptom awareness, said Martin Zamani, MD and first author of the article. He continued:
– We must also become better at answering the questions that cancer pa-tients and their relatives have once they are informed that their illness is due to a sexually transmitted virus, because this can be very taboo.
Patients were infected by a type of HPV covered by a vaccine
The research project also shows that 86% of patients who were diagnosed with HPV-related oropharyngeal cancer were infected by HPV-type 16, and a further 9% were types of HPV covered by the vaccination programme:
– We know that it takes many years for HPV to become cancerous, and re-sults indicate that increasing and broadening vaccination against this spe-cific type of HPV is crucial to reducing the number of oropharyngeal can-cer cases, said Martin Zamani.
Within the next few years, cases of HPV-related oropharyngeal cancer will surpass the number of HPV-related cases of cervical cancer, which have declined after the introduction of the HPV vaccination of girls. Boys be-tween the ages of 12 and 18 can now be vaccinated against HPV:
– The vaccination programme shows promise, even though we’ll only see its effect in a few decades, explained Martin Zamani. He also said that future research will also focus on diagnostic evaluation methods in order to catch cases at an earlier stage.
FACTS FROM THE RESEARCH PROJECT
HPV+ patients with oropharyngeal cancer:
• Threefold increase in HPV-related cases of oropharyngeal cancer from 0.9 per 100,000 inhabitants in 2000 to 3.2 per 100,000 inhabit-ants in 2017.
• Typically men, non-smokers, and younger compared to HPV nega-tive patients with cancer caused by tobacco and alcohol.
• 95% of patients were infected with a type of HPV covered by the HPV vaccination
• HPV+ patients often presented with a swelling/lump on the throat and a small tumour on one tonsil or on the base of the tongue.