HPV linked to throat and mouth cancer
Posted Monday, March 7 2016 at 02:00
Human papillomavirus (HPV) also causes several other types of cancers such as the oesophagus cancer which affects the gullet, cancer of the penis, anal cancer and vulva cancer. It also causes cervical cancer which by far is the most common in Uganda.
Commonly known for being the cause of cervical cancer, Human papillomavirus (HPV) has now emerged to cause mouth and throat cancers.
A 2012 research paper by Anil K. Chaturvedi titled ‘Epidemiology and Clinical Aspects of HPV in Head and Neck Cancers’ also shows that whereas head and neck cancers were common and were traditionally caused by tobacco smoking and alcohol use, HPV infection has, however, become a risk factor that could cause these cancers as well.
“Head and neck squamous cell carcinomas which include cancers of the oral cavity, oropharynx, and larynx, are the sixth most common cancers worldwide with an estimated annual burden of 355,000 deaths and 633,000 incident cases. Over the past 10 to 15 years, HPV infection has been increasingly recognised as a major etiologic factor for a subset of these cancers arising from the oropharynx, including the base of tongue, tonsil, and other parts of the pharynx,” the paper reads in part.
In Uganda, according to Dr Fred Okuku, an oncologist at the Uganda Cancer Institute, the virus is common along the anal and genital area and as a result the cancers that arise are found along those areas.
“HPV can cause several types of cancers such as the oesophagus cancer which affects the gullet, cancer of the penis, anal cancer and vulva cancer. It also causes cervical cancer which by far is the most common in Uganda,” Dr Okuku explained.
2014 data from the Cancer Institute shows that 1,062 oesophagus related cancers were reported, 264 were for nasopharynx and 110 were recorded for the cancer of the penis, among others.
However, these cancers are not specifically caused by the virus.
Dr Jeff Ottiti, a consultant ENT (Ear, Nose and Throat) head and neck surgeon at the cancer institute adds that whereas cancers caused by tobacco smoking and alcohol in the throat and mouth have are reducing, those caused by the virus are steadily increasing.
“HPV related throat and mouth cancers are said to have started appearing when the sexual revolution took place in the 1960’s. It was estimated that this particular cancer will increase exponentially between 2010 and 2030 if unchecked. At the moment, there are more cancers not related to smoking that are on a rise and after research, it was found out they were HPV related,” Dr Ottiti explains.
Dr Ottiti says in Uganda, exact data on how many people are affected has not yet been collected because throat cancers are not tested for HPV although studies are being carried out.
In developed countries though, Dr Ottiti says when the revolution took place, there was an increase in the cases registered till the 1990’s but an exponential rise took place in the 2000’s.
Literature reviews conducted by epidemiologist Aimée R. Kreimer in 2005 stated that HPV related DNA was detected in 35.6 per cent of oral cancers in the US.
To find out information locally, he adds, we need to find where in the revolution Uganda is.
“At the moment, the only thing I can say is that this type of cancer is common in men and women aged between 30 and 40 as opposed to other cancers which are common in those aged above 40 and above. This could probably be because most people nowadays get sexually active in their teens,” he adds.
Despite not having clear data, Dr Ottiti says there is a reason to worry because of the sexual revolution where people become more promiscuous and start exploring. When this happens, cancers are bound to increase, he adds.
Oral sex which involves use of the mouth to have sexual pleasure is one of the leading causes of head and neck related HPV cancers, Dr Okuku said. He went on to say that the practice which is largely growing in the country allows the person who practices it to carry the germs from anus or the genitalia to the mouth and throat.
“Homosexuals who mostly carry out this type of sex are at a high risk,” Dr Okuku explains.
Dr Chaturvedi writes that previous studies showed higher oral HPV prevalence among men than women for example a US National Health and Nutrition Examination Survey study said oral HPV prevalence was significantly higher among men than women; 10.1 per cent and 3.6 per cent respectively which could be alluded to their sexual orientation.
However, Dr Ottiti stresses that not everyone who has throat or mouth cancer should be called names and thought to have practiced oral sex but rather that people who practice this type of sex are at a high risk of getting infected especially if they have multiple sexual partners.
Multiple sexual partners
Since it is a sexually transmitted virus, Dr Okuku says it is not a surprise that multiple sexual partners pose a high risk of infection. He adds that if a person has it but does not have multiple sexual partners, the virus can lay dormant; this changes once more than one sexual partner is involved.
“Once there is intercourse, the virus can easily be transmitted from one person to another, this virus has to be transmitted by the male organ,” Dr Okuku explains.
Dr Ottiti adds that being faithful is very important in relationships because it reduces the chances of getting infected with any type of infections. He continues that multiple sexual partners also pose a risk of continuous exposure hence increases risk of development that is why it is a very big risk factor.
Dr Okuku said one of the risk factors is smoking which can easily bring wounds to the mouth and make it easier for the infection to take place.
“Smoking deprives the mouth of the ability to fight off these oral cancers and we are not looking at active smoking only, even passive smokers are susceptible,” Dr Okuku explained.
However, Dr Chaturvedi in his paper says current smokers face a higher risk of getting infected as opposed to former smokers or those who have never smoked before. He suggested that there is a possibility that smoking-induced immune-suppression could potentially play a role in the infection.
Dr Okuku said the virus easily replicates in the saliva and if it gets access to the blood through open wounds, then it further multiplies which makes it easier to develop cancer. For this to happen though, he said when kissing, one should be careful not to have wounds in the mouth. However, it can only be a risk factor if the person in question has the virus.
“Kissing is exchange of saliva yet the mouth has a lot of germs. When this exchange takes place, if the immunity is good, it will help you not attain the virus but if not, then you can easily develop cancer,” Dr Okuku explained.
Gypsyamber D’Souza reported that oral HPV prevalence increased with increased number of open-mouth kissing partners among college-aged men, suggesting the possibility of salivary transmission of oral HPV infection.
Dr Jeff Ottiti adds that unlike smoking and alcohol related throat and mouth cancers which take years to develop, HPV related mouth and throat cancers appear much faster and respond positively to treatment.
“If in early stages, surgery is best option. If it is for the tonsils, the tonsil is removed and if it is the lymphs, then these that are infected are removed by use of the open neck surgery,” he explains.
However, if in extensive stages and cannot be treated, he says the patients has to undergo chemo-radiation.
Dr Okuku says although this type of cancer should not worry us because it is not very common but rather the culture of homosexuality since it is them that are susceptible to getting the virus more.
Dr Ottiti calls for the sticking to the ABC (Abstinence, Being faithful and Condom use) method of prevention. He adds that individuals should desist from early sexual intercourse because it increases their chances of getting some of these illnesses.
Signs and symptoms
Dr Jeff Ottiti explains that after the virus finds its way to the throat or mouth, its gene prints itself on the normal genes of the person and ends up dominating and controlling them to multiply cells rapidly unchecked. He says unlike normal genes which control cell multiplication, these genes allow for the rapid growth of the cells which can then become cancerous.
Once this happens, he says there will be changes in the throat and mouth but identifies two symptoms that individuals should look out for.
Swelling in the throat; Dr Ottiti says the virus can attack the tonsils and cause them to swell or enlarge.