HPV, that’s the virus that causes cervical cancer, right? Yes, but did you know that the virus also increases the risk of head-neck cancer? And that vaccinating not only protects women but also men against cancer? We discuss fact and fiction about the Human Papilloma Virus, along with head-neck oncological surgeons Remco de Bree and Johannes Rijken.
Boys need a vaccination to protect girls against HPV
Fiction
“This really is a persistent misconception among adolescent boys,” says Johannes. “Yes, women can get cervical cancer from HPV, as well as cancer of the vagina and labia. But the virus can also cause cancer in men, such as cancer of the anus and penis. And, in addition, both men and women can get oropharyngeal cancer from HPV.”
The oral pharynx, or oropharynx, is located in the back of the throat. HPV does not play a role in the oral cavity and the rest of the pharynx.
HPV spreads through sex
Fact
The same is true for HPV as for other STIs: the diseases are spread through sexual intercourse. The virus can also be transmitted through oral sex, though, which may lead to cancer in the oral pharynx. “Oral sex and the number of sexual partners are obvious risk factors for oropharyngeal cancer,” Remco explains. “The virus can travel from the cervix to the oral cavity.”
“But there is also strong evidence that the virus can spread indirectly, through the hands, fingers, skin or mouth,” Johannes adds. This danger exists especially if the genitals have just been touched.
Vaccination is especially useful before you become sexually active
Fact
The vaccine protects against HPV, but does not remove it when it is already present in your body. Remco: “You have to prevent getting HPV, and you do that through safe sex and vaccination. Once the virus has entered your body, there is little point in getting a shot. People usually get infected at a young age. Then, the virus can keep quiet for years, and around age 40, it might have culminated into head and neck cancer. That’s why it’s so important to get vaccinated as an adolescent, and preferably even earlier.”
“It’s important to get vaccinated before you become sexually active.”
There is only one kind of HPV
Fiction
“There are different subtypes of the virus, and not all of them lead to cancer,” Remco explains. “People are only at risk from the so-called ‘high-risk variants’. The vaccination in the Netherlands protects against HPV subtypes 16 and 18, which are by far the most common pathogens.”
If women have been vaccinated against HPV, they will no longer need a smear test
Fiction
Because there are HPV variants that the vaccine does not protect against, such as subtype 33, it is still important for women to participate in the national Cervical Cancer Screening Program and have a smear test. “And it’s also important to see your GP if you are having throat symptoms for more than three weeks,” Remco adds.
A throat swab is of no use with HPV
Fact
With COVID, for example, you make a throat swab to detect the virus. Why is that not possible with HPV? “HPV is much less sensitive to saliva testing than COVID,” Remco says. “HPV nests much deeper in the throat, in the tonsil tissue, in the little area we call Waldeyer’s ring. That consists of lymph node-like tissue, which catches all kinds of bacteria and other germs from the air going to your lungs.”
The ultimate goal, however, is to someday find an easy test to search for HPV in the oral cavity. Remco: “Ultimately, of course, we aim for a test that does not require a visit to the specialist in the hospital, because we would like people to catch the virus earlier, before they develop symptoms. Something their GP might perform, like a cervical smear test, would be ideal, for example. A lot of research is still needed for such an easy test, but I believe something will eventually come.”
Once you have HPV, you will never get rid of it
Fiction
8 out of 10 people will get infected with HPV at some point in their lives. You won’t notice it once you’ve catched it, and in most cases your body will clear the virus within 2 years. With about 20 percent of people, the infection won’t disappear. The virus may then start infiltrating and damaging cells. Those abnormal cells might grow into cancer.
“HPV may remain less active for a while, but can then still be present,” Remco says. “We see this, for example, after we have treated people for an oropharyngeal tumor. After radiation (radiotherapy) and chemotherapy, the virus has usually been ‘destroyed’ along with the tumor. It has then dropped below a certain critical threshold. We have strong suspicions that the chance of the cancer coming back becomes higher once HPV starts to become active again.”
To investigate these suspicions further, Remco and his team received a large grant (nearly 1.3 million euros) from KWF Dutch Cancer Society in 2023.
“After people have been treated for oropharyngeal cancer, they will enter an intense follow-up scheme,” Remco says. “For five years, we will see them every few months; a total of at least 10 visits. During a check-up, we will now also test their blood for HPV. We want to follow how the virus will develop.”
Remco and his team collaborate with 13 other head-neck centers in the Netherlands for this research project. “What is the critical limit of HPV: when does the cancer return? How should we interpret the results? What is the best moment to test for HPV? Which blood test works best? We still have to learn all that.”
Recently, the researchers have received another grant (2.1 million euros) from KWF Dutch Cancer Society. With this, they will simultaneously nationwide investigate a potentially even more sensitive HPV test in a similar way. This blood test was developed at Amsterdam UMC and is being studied in close collaboration with UMC Utrecht.
No HPV found in your cervical cancer smear test? Then, your entire body is HPV-free
Fiction
Good news: you don’t have be afraid for cervical cancer; the virus has not affected any cells in that area. “But HPV may still have hidden itself in your tonsil tissue, over time triggering the development of cancer in the oral pharynx,” Remco clarifies.
People with oropharyngeal cancer are older
Fiction
“The classic oral pharyngeal cancer patient is indeed somewhat older, 63 years old on average. These are often smokers and drinkers, and more men than women,” says Johannes. “But HPV-related head-neck cancer patients are actually much younger when they get the disease. They often live healthy lives, don’t smoke or drink and exercise plenty.”
“We don’t see them until they have obvious symptoms, usually a swelling in the neck,” Remco adds. “They typically have a large lymph node metastasis and a small primary tumor. In contrast, the classic patient with oral pharyngeal cancer often has a large primary tumor.”
The prognosis of the HPV-related patients is better, though. “Their tumors respond more strongly to radiation, and the physical condition of this group of patients is better. The classic patient with oropharyngeal cancer receives the same treatment but often has a moderate prognosis.”
“You can be young and in top shape and still get head and neck cancer.”
“So, it’s important to realize that you can also get this disease when you’re in young and in top shape,” Johannes warns. “We see the oropharyngeal cancer rates going up and are treating younger patients more often. This is all caused by HPV. That’s exactly why this vaccination is so important. If more young people get vaccinated, hopefully in time, we will have to treat fewer HPV-related head-neck cancer patients. We are already noticing that fewer women are getting cervical cancer in the first countries that started vaccinating against HPV.”
Oropharyngeal cancer requires drastic surgery
Fiction
Surgeons used to routinely remove tumors from the oral pharynx but this is usually no longer done. “With surgery, you’ll have to create an access route to the tumor, and in doing so, certain structures may be left damaged,” Remco clarifies. “Speaking and swallowing, for example, can be affected. By using radiotherapy, with or without chemotherapy, these functions will be better preserved. With this standard treatment, it is also possible to make the cancer disappear completely.”
For now, HPV-related tumors are treated in the same way as ‘smoking and drinking tumors’. However, worldwide studies are now underway to determine whether it is possible to make the treatment of HPV-related oropharyngeal cancer less intense because these tumors respond better to treatment.
“On the other hand: perhaps the HPV group also responds better to treatment because they are healthier in general? And perhaps a weakening of the treatment will actually cancel out the positive effect? That really needs to be researched properly first,” Remco says.
With the help of multiple innovations, radiation and chemotherapy are also becoming less and less stressful for patients. With the MR-Linac, for example, head and neck tumors can be irradiated more precisely. As a result, fewer sessions are needed: 10 instead of the 30 to 35 radiations with a conventional radiation device, for example.
“In addition, we are also doing extensive research on predicting the outcome of radiotherapy so that we will be able to, among other things, adjust the intensity of treatment early on,” Remco explains. “During radiotherapy treatment, we would therefore also like to regularly determine the HPV level in the blood of HPV-related oropharyngeal cancer patients.”
If women have cervical cancer, their partners do not have to run to their GP immediately to get checked for HPV and cancer
Fact
You are indeed more likely to get cancer of the oral pharynx, if your partner has HPV and/or cervical cancer. “But statistically that chance is incredibly small, because cancer in the head and neck region is still rare. Screening in advance will therefore create unnecessary stress for people, and a lot of healthcare expenses,” says Johannes.
Every year, about 900 women in the Netherlands are diagnosed with cervical cancer. The chances that they or their partners also have oropharyngeal cancer is very limited. Only 3 percent of all cancers are located in the head and neck area. And that number includes not only cancers in the oral pharynx, but also head and neck tumors not caused by HPV, such as vocal cord, tongue or salivary gland cancers. And it also includes the patients with oropharyngeal cancer caused by smoking or drinking. So, the percentage for specifically HPV-related oral pharyngeal cancer is much more lower than that 3 percent.
And an MRI scan, just to be sure, to check for cancer in the oral pharynx when you or your partner has cervical cancer? “That too is of little use, because in the rare case that there is already a tumor present in your tonsil tissue, it is often still very small. Then, you will only have false certainty,” says Johannes.
“But if you get symptoms in the head and neck area and they persist longer than 3 weeks, you do need to go to your GP, because there is of course a slightly increased risk of oropharyngeal cancer if your (ex-)partner has cervical cancer,” Remco adds.
(Sources statistics: IKNL and RIVM)
Get (your child) vaccinated!
In the year that children turn 10 years old, they automatically receive an invitation for the HPV vaccination in the Netherlands. This involves a total of 2 shots, with six months between the first and second shot.
Are you over 18, not yet sexually active and still want to be vaccinated against HPV? This is, of course, possible, but you will have to pay for the vaccinations yourself (about 175 euros per shot).
Starting at age 30, Dutch women receive an invitation to participate in the national Cervical Cancer Screening Program for free. Every 5 years, they are invited to have a smear taken by their GP or do a self-test.
In the lab, the smear is checked for HPV. If the virus is detected, the sample is also checked for suspicious cells and possible cancer.
