70% of oral cancers are associated with HPV, says Okoye
•Malignant growths treatable if caught early, avoidable with vaccination
•Vaccine won’t reverse HPV-associated tumour trends until 2060
Prof. Ifeoma Okoye is a medical doctor. She is a Fellow of the West African College of Surgeons), Fellow of the Nigerian Medical College of Radiology, Professor of Radiology at the College of Medicine, University of Nigeria, Nsukka/University of Nigeria Teaching Hospital Enugu (UNTH).
She was appointed Director of the University of Nigeria, Centre for Clinical Trials -UNNCECT, which she is running in collaboration with the Centre For Clinical Research, University of Cape Town (CRC-UCT). She is also the Editor of The West African Journal of Radiology, and she was awarded an Ashoka Fellowship, in recognition of being a Change-Maker, through her renowned Social Entrepreneurship Work.
Okoye has put in over 15 years in Clinical Research, playing several roles, as Founder and President of Breast Without Spot Cancer, a Non Governmental Organisation (NGO), and she has been involved in several other academic, social and intellectual projects across Africa.
Okoye, in this interview with The Guardian, alerted to rise in cases of oral and throat cancers in Nigeria and that 70 per cent of oral cancers are associated with Human Papilloma Virus (HPV), which causes cervical cancers. She, however, said cancers are treatable if caught early and avoidable with vaccination but vaccines won’t reverse HPV-associated cancer trends until 2060.
CHUKWUMA MUANYA writes.
Why the recent rise in oral and throat cancers?
The rising incidence of throat cancers (which medically are termed; ‘oropharyngeal cancers’ or ‘oral and throat’ cancers) is truly unfortunate and of grave concern, especially as there is evidence that improving the knowledge, attitudes and practices toward our sexual health can considerably stem the current upward trend!
Sustained, chronic infection with Human Papilloma Virus (HPV), which is already famous for causing almost 100 per cent cervical cancers, also is the underlying culprit in throat, anal and penile cancers! The rising incidence of these cancers, among men, is indexed on the uptick of the HPV infection in men and their sexual partners! Current literature shows that 70 per cent of oropharyngeal cancers are associated with HPV.
Oropharyngeal cancer, which refers to cancers that affect the back third of the tongue, soft palate, tonsils, and sides of the throat, is most commonly caused by the human papillomavirus (HPV), the most prevalent sexually transmitted infection in the United States (and I am sure globally). The HPV is thus an exceedingly common virus—which most sexually active individuals have already been exposed to! Fortunately, It’s also preventable with a vaccine.
Though amenable to primary prevention with the already available & accessible HPV Vaccines, the United States Centers for Disease Control and Prevention (CDC), of the US, further raised the alarm that; 90 per cent of men and 80 per cent of women will be infected with the virus at some point in their lives. The CDC emphasised that half of these infections will be with the high-risk types of HPV. The window of opportunity which makes this high infectivity prevalence, not in and of itself alarming, is that; most of the time, our immune systems can clear ‘an HPV infection’ within a year or two on their own, without further issues. However, if a high-risk HPV infection lingers, cellular changes can occur that may cause cancer to develop over time (usually many years—or even decades-10-20years ‘infectivity window’ —after acquiring the infection).
Classically, heavy drinking and smoking were considered, up until recently to be the primary risk factors for oropharyngeal cancer, but current literature, reveals that: over the last several decades, the number of alcohol- and tobacco-associated cancers has declined, while there has been a marked increase in oropharyngeal cancers associated with oral HPV infection.
This throat cancer, has been found to disproportionately affect middle-aged men who were never heavy drinkers or smokers, and there are an estimated 14,800 new cases of HPV-positive oropharyngeal cancers diagnosed in men, compared to 3,400 in women each year in the US.
Is oral sex implicated in throat cancers?
There is definitely confusion about HPV, oral sex, and oropharyngeal cancer, however, scientific studies, have been able to bury the opinion that the association is a myth and have obtained incontrovertible evidence that there is a relationship between sexual practices and the rates of oropharyngeal cancer
According to one study, even if you’ve engaged in oral sex with just one sex partner, there is 14.3 per cent risk of acquiring HPV.
You can acquire HPV from sexual contact through vaginal, anal, or oral sex or through intimate touching with someone who has an HPV infection. The virus spreads from the original point of transmission, genitally or orally. For example, when acquired genitally, it can be spread orally through oral-genital contact.
Eighty-five percent of sexually active adults (between 18 and 44) have had oral sex, according to the CDC. The rise in head and neck cancers of the oropharynx in nonsmoking young men is linked to oral sex—but not completely. While the total number of oral sexual partners over a lifetime increases the risk of oral HPV, just because someone is diagnosed with this cancer doesn’t mean he/she had a lot of sexual relationships.
There are 100 different kinds of HPV, with some HPV strains riskier than others! There are 40 types of HPV that can be spread through sexual contact (genital, oral, anal, deep kissing, sexual touching, and skin-to-skin sexual contact, which includes spreading an existing infection from one body location to another), as well as from mother to child during childbirth. It is easy to envisage, transmission through exchange of microphones among musicians! Condoms, even if worn in a trouser form, cannot prevent transmission.
Most concerning is a small group of 15 high-risk types, which can cause oropharyngeal, cervical, vaginal, vulvar, anal, and penile cancers. Of those, HPV Type 16 is far more likely to stay in the body and eventually develop into cancer than any of the other high-risk HPVs. It causes 95 per cent of all oropharyngeal cancers caused by HPV.
Of the 100 kinds of HPV, some strains cause common warts (or papilloma) that school-aged kids often get on their hands and feet. HPV infections are acquired through skin-to-skin contact, by touching objects, others have touched, and from the floors of public pools and locker/Rest rooms/toilets via small cuts or breaks in the skin. These warts can be embarrassing, and extremely painful, but are harmless—meaning they don’t lead to cancer.
What have been the challenges in prevention and treatment of oral cancers?
Awareness on maintaining; better sexual lifestyle habits, inter-personal hygiene, and general healthy lifestyle modifications, should reduce risk of the infection running a chronic course, that would then lead to cancer!
There are not too many of us, who hasn’t been challenged with a sore throat, a hoarse voice or a lump in the neck! Usually these are minor problems that go away on their own or after a course of antibiotics—but if they don’t, advice is to have a medical check, with your doctor.
A sore throat, hoarse voice, lump in the throat, difficulty swallowing, or a lump or patch in the mouth (including on the tongue) might be symptoms of oropharyngeal cancer.
Signs of oropharyngeal cancer can be swollen lymph nodes, pain when swallowing, and unexplained weight loss. But sometimes, there are no signs at all, if the lump is in, on, or near the mouth, oral cavity. (All of these fall into the category of head and neck cancers.)
These forms of cancer are both hard to detect and are on the rise. The good news is they are treatable if caught early and, even better, entirely avoidable for people who follow the recommended schedule for HPV vaccination.
While HPV vaccine is available, it may only help those who haven’t already come in contact with the high-risk strains of HPV that can cause cancer! A focused, intentional HPV vaccination programme, can be infused into any country’s cancer control programme, for both boys and girls, targeting the population of pre-sexual exposure ages (which for Nigeria has been set at nine-13 years)! However, concerted community awareness and engagement is also needed to negotiate ‘Vaccine Hesitancy’! A ‘rude shock’ I had of ‘massive/out right’ vaccine rejection’ during a free HPV vaccination roll out in young girls in a rural community, without adequate community engagement to ensure acceptability!
Most HPV-related head and neck cancers are preventable, and high-risk strains of HPV are almost entirely prevented by vaccination. Getting vaccinated against HPV (preferably before an individual becomes sexually active) can dramatically decrease the risk of that individual.
It is important to know, also, that even if one does get the vaccine as an adult, it only protects against HPV strains that the individual hasn’t been exposed to in the past.
According to the CDC, the HPV vaccine was developed to prevent cancers in the reproductive tract. Because the vaccine protects against the types of HPV that can cause oropharyngeal cancers, it may also prevent oropharyngeal cancers. But not enough studies have been done to verify this.
Unfortunately, it is not possible to know if you or someone you are in a relationship with has, or had, an oral HPV infection, since there are no visible signs in or around the mouth. Unlike other sexually transmitted infections, there isn’t a routine clinical test to check for oral HPV. It is possible to have an oral and genital HPV infection at the same time. However, there is no test to detect an active ‘oral HPV infection’, or treatment for it.
Low-risk sexually transmitted HPV, such as types six and 11, cause 90 per cent of genital wart cases (strains of HPV that do not cause cancer)! Genital warts are cauliflower-shaped bumps (like large bumps of a frog-skin) that can appear in the genital or anal area. Though painful, undesirable and unsightly, genital warts can be treated with prescription medication.
Usually referral happens after patients with symptoms go to a doctor who sees a mass, at which point, the doctor will need to order a series of imaging scans: A Cytoplasmic Tomography (CT) scan is often the first test to assess the mass and determine whether it has spread; if positive, a PET scan may then be done to determine the stage of oropharyngeal cancer; and an Magnetic Resonance Imaging (MRI) may be used to assess the involvement of surrounding areas and to determine what treatment is best for that particular patient.
Going forward, what are your recommendations on how to prevent, control and treat oral cancers?
Once detected, HPV-positive cancers can be treated through surgery, radiation, or a combination of chemotherapy and radiation. The choice of therapy is often guided by tumor location, size, and extent of lymph node involvement. Because the tissues in the mouth and back of the throat are delicate, oropharyngeal cancer requires highly specialized care to minimise long-term speech and swallowing difficulties.
While patients can present with very bulky disease (masses that are visible on exam or imaging studies), patients with HPV-associated cancers can have very high cure rates! However, even with early-stage cancer, patients are at risk for subsequent speech and swallowing difficulties, due to side effects of curative treatment.
Rates of HPV-related cancer are expected to continue to rise for a good while, because the cancer takes years or decades to develop (10-20yrs). That is why awareness is important, as this type of cancer is treatable.
It is important to note that, even if the vaccine doesn’t help those of us who are over 40, we can prevent this cancer from affecting the next generation,
To date, where populations in High Income Countries (HICs) have virtually eliminated cervical cancer, Low and Middle Income Countries (LMICs), such as Nigeria, are still to do anything significant in this space! The vaccine won’t reverse the HPV-associated cancer trends we’re seeing, epidemiologists estimate, until 2060.