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Wednesday, December 13, 2017

OROPHARYNGEAL CANCER AND HPV 16

HPV is the most common sexually transmitted virus and infection in the US.

There are nearly 200 different strains of HPV, most of which are harmless and do not cause cancer. Out of all these, 9 are known to cause cancers, and another 6 are suspected of causing cancers as they are commonly found along with one of the nine we know to be oncogenic. In oral cancers, we are primarily concerned with HPV number 16 which is also associated with cervical, anal, and penile cancers besides those of the oropharynx.

You can have HPV without ever knowing it because the virus often produces no signs or symptoms that you will notice, and the immune response to clear it is not a process that you will be aware of.

Every day in the US, about 12,000 people ages 15 to 24 are infected with HPV. According to data from the ongoing NHANES study, approximately 26 million Americans on any given day have an oral HPV infection. Of those approximately 2600 are HPV16. The vast majority of individuals will clear the virus naturally through their own immune response, and never know that they were exposed or had it.

If you test positive for HPV, there is no sure way to know when you were infected with HPV, or who gave it to you. A person can have HPV for many years, even decades, before it is detected or it develops into something serious like a cancer. In the vast majority of infected people, even with a high-risk version of HPV known to cause cancers, they will not develop cancer.

Testing positive for an HPV infection does not mean that you or your partner is having sex outside of your relationship. It is believed to have long periods of inactivity or dormancy that may even cover decades; these are periods of time that you will test negative for it.

Sexual partners who have been together for a while tend to share all types of sexual infections. Typically if one partner has a fungal infection like Candida, the other partner has it as well, even though they may appear to be asymptomatic. The same is true of other common sexual infections like Chlamydia, a bacterial infection. HPV viral infections also are commonly shared. This means that the partner of someone who tests positive for HPV likely has HPV already, even though they may have no signs or symptoms. Like most Americans, their immune system will customarily clear it in under 2 years.

Condoms may lower your chances of contracting or passing the virus to your sexual partners if used all the time and the right way. However, HPV can infect areas that are not covered by a condom- so condoms may not fully protect against HPV.

Because of its ubiquitous nature, the CDC says that more than 80% of Americans will have an HPV infection in their lifetimes. For most of us, this occurs late in our teens and twenties when our sexual activity is the highest and the number of partners is likely the greatest. 

The human papilloma virus (HPV) is a double-stranded DNA virus that infects the epithelial cells of skin and mucosa. The moist epithelial surfaces (squamous cells) include all areas covered by skin and/or mucosa such as the mouth interior, throat, tongue, tonsils, vagina, cervix, vulva, penis (the urethra – the opening), and anus. Transmission of the virus occurs when these areas come into contact with a virus, allowing it to transfer between epithelial cells. While it is established now that sexual contacts, both conventional and oral, are means of transferring the HPV virus through direct skin to skin contact, it is still poorly understood what other transfer pathways may exist. It is highly unlikely that the virus can live for long on inanimate objects outside of a cell.

The leading cause of oropharyngeal cancer is from HPV, a very small number of oral cavity cancers also occur from HPV. The HPV family contains almost 200 strains, and it is one of the most common viruses in the United States. It is important to understand that of all these, only nine are associated with cancers. Of the nine that are high risk, only one is strongly associated with oropharyngeal cancer, HPV16. A handful or more are associated with benign growths (warts) and the vast majority we have no evidence, other than they exist, that they harm us in any way.

The CDC says that up to 80% of Americans will have HPV infections in their lifetime and 99% will clear these infections without consequence, or even knowing that they had the infection, as it produces no symptoms they will notice. The body’s immune system is usually able to get rid of an HPV infection and many infections come and go without causing any problems, or an individual even knowing they were infected. 

The information provided is not meant to scare you. Oropharyngeal cancers while increasing rapidly in incidence, are still a very small risk in our world. It is meant to educate you about the risk factors and signs and symptoms of oral and oropharyngeal cancer. An informed individual will be able to self-discover something which is going wrong and bring it to the attention of a medical or dental professional for the earliest possible diagnosis of a problem.

Early discovery has many positive impacts when you consider cancer; potentially longer life spans, and reduction of treatment related morbidity, which significantly improves post cancer treatment quality of life.

There is no cure for the virus. Most of the time, HPV goes away by itself within two years and does not cause health problems. It is only when HPV stays in the body for many years, usually decades, that it might cause these oral cancers. Even then, it is a very small number of people that will have an HPV infection cascade all the way into an oral malignancy, though that number is increasing every year by about 10%. 

It is not known why HPV goes away in most, but not all cases. For unknown reasons there is a small percentage of the population whose immune system does not recognize this as a threat and it is allowed to prosper. Although HPV can increase the risk of developing some types of cancer, most people who have HPV do NOT develop cancer.


I'm in the 1% of the population that was not able to clear the HPV infection.  My immune system was not able to get rid of the HPV infection that laid dormant in my body for over 20 years.

There are therapeutic vaccines under study which may be able to suppress viral loads and prevent recurrences in patients with HPV positive tumors. The results from these has yet to be published, and we are far from knowing definitively that this is possible.


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