[Question #3163] Oral HPV 16 and throat cancer risk
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91 months ago
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Hello Dr. Handsfield/Dr. Hook-
I am a 33 y/o male and I'm asking about the risk of throat cancer from oral HPV infection.
I've read that close to 10% of males have oral HPV and 1-2% have cancer causing oral HPV 16. I've read that your HPV risk skyrockets based on other factors - being a male, performing oral sex on multiple partners, etc. I'm concerned because in my late 20s I was promiscuous -- eight oral sex partners and a few more vaginal sex partners. I've found a couple articles showing a link between oral lichen planus and oral HPV 16 infection. I had OLP for a couple months late in my promiscuous days -- my dentist and an oral surgeon both said it was likely an allergic reaction but I now feel like it very well could have been HPV in my mouth. It has gone away.
I understand that most HPV infections will clear on their own and the ones that don't are at risk of turning into throat cancer, but I am wondering....
1) What percentage of ORAL HPV infections actually clear?
2) By "clear" does this mean the virus is totally gone? Can the HPV virus "clear" and then flair up down the road?
3) Mostly importantly... if I have/had oral HPV 16, and if my body has been unable to clear it, what is my risk of developing a head and neck cancer? Does chronic oral HPV 16 lead to cancer everytime, sometime, rarely, etc? Even if I could say with certainty that I have persistent oral HPV16, does this mean I am bound to get HPV throat cancer?
I am a non smoker FYI.
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H. Hunter Handsfield, MD
91 months ago
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Welcome to the forum. Thanks for your question. I also appreciate the evidence that you have apparently reviewed other threads with quesitons like yours, e.g. your understanding that most oral HPV clears on its own and does not lead to cancer.
With all the media attention to throat cancer and HPV in the past decade, not surprisingly we've had many questions like yours. The most recent, in which I posted a blog-like reply precisely to respond to further questions like yours, was just 2 weeks ago, question 3098, username Jennifer. It directly or indirectly addresses your questions as well as substantially more information. I would also encourage you to look at the American Cancer Society's summary of the frequency of various cancers, including pharyngeal (throat) cancer:
One bottom line is that oral HPV (HPV16 in particular) and pharyngeal cancer resulting from it are less common than you seem to have come to think and fear. Last I heard, something like 40% of all people will ultimately die of cancer. However, HPV related pharyngeal cancer remains a distant also-ran in statistical frequency. Even people with the largest number of sex partners, including very frequent oral sex (hundreds of partners in a lifetime) have far higher risks of cancers of the colon, prostate, blood/lymphatic, breast, etc.
Directly to your questions:
1) Hard to know with precision, because testing doesn't necessarily pick up all infections. But probably 90-99% of infections are cleared by the immune system and do not lead to cancer.
2) Good question. Some data suggest, and some experts believe, that all HPV infections persist indefinitely, in that HPV DNA persists in infected tissues. However, the large majority of infections are believed to be cleared by the immune system to a point that they cannot be detected with present technology, do nor reactivate, and cannot be transmitted to partners. Obviously there are exceptions, as in women who develop abnormal pap smears many years after they plausibly could have acquired HPV.
3) There are no data ton answer this. I see no reason to believe your immune system would not clear an oral HPV16 infection, if you ever had one. But a simple back-of-the-envelope calculation says that the large majority of HPV16 infections don't progress to cancer. Just look at the annual numbers of throat cancer (in the ACS data cited above) and contrast those numbers (a few thousand cases per year) with the millions (?) of oral HPV infections that must occur, given the frequency of finding HPV in various epidemiologic studies.
Also take a look at thread 3098, then let me know what additional questions you may have. In the meantime, I hope these comments are helpful.
HHH, MD
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91 months ago
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Thank you for your reply.
Couple questions if you don't mind....
1) I saw articles that linked oral lichen planus and HPV 16. Is knowing I had OLP at my age enough to assume it was from oral HPV or more specifically a high risk one?
2) When news articles say 1 percent of adults have oral HPV 16, wouldn't it be safe to assume then that a ton more than that have had it at some point and cleared it?
3) in this article...
http://www.nydailynews.com/life-style/health/oral-cancers-hpv-epidemic-men-preventable-article-1.1361894
A doctor says chronic oral HPV increases your chances of getting throat cancer by 234? Can this really be true?
Sorry for being so specific but im a numbers person so wrapping my mind enough this stuff will help put my mind at ease (I hope).
Thank you for your attention and professionalism.
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H. Hunter Handsfield, MD
91 months ago
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1) To my knowledge, an association between HPV and lichen planus probably is real, but I am unaware of any data that links LP with increased risk of HPV related cancer, either oral or genital.
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2) I'm not familiar with the research studies behind such news reports, but in general you are right: whatever the proportion at any point in time, a lot more people probably have had it at one time or another.
3) I cannot discern the scientific source of that statistic and not sure exactly how to interpret it. But I suppose it is plausible. However, keep in mind the difference between proportionate increased risk and actual risk. Smoking increases the risk of lung cancer by a giant proportion (let's say 100 fold, although that's only a guess), yet most smokers don't get lung cancer. In this case, let's say that the baseline risk of pharyngeal cancer is 1 in a million. A 200-fold increase means that the risk rises to 1 in 5000. Still awfully good odds that any particular person with oral HPV will never get pharyngeal cancer! (These are wild guess numbers -- I'm making a statistical point, not citing actual risk calculations, which I don't know.)
It seems clear you are obsessed by all this, and spending a lot of time searching online about it. LIke many anxious internet users, you probably are being drawn to information that inflames your fears and missing the more reassuring bits that also are there. As the popular media statistician Nate Silver (of fivethirtyeight.com) wrote in his book The Signal and the Noise, "Give an anxious person a computer with an internet connection and soon he'll believe his cold is the bubonic plague" (approximate quote).
Bottom line: there is absolutely nothing in all you have asked that suggests you have anything other than a very small risk of ever getting pharyngeal cancer due to HPV. Do your best to go forward without worry about it.
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91 months ago
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Thank you for the reassurance. It does mean a lot.
I'm belaboring the point here, but if lifetime risk for oropharnygeal cancer is 37 per 10,000 (link below), then a 234 fold increase for chronic oral HPV would leave an 89% chance for chronic oral HPV sufferers of getting cancer. That's pretty scary. Correct? Or am I oversimplifying?
https://www.medscape.com/viewarticle/887728
I understand you have to close the thread. Thanks for your guidance.
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H. Hunter Handsfield, MD
91 months ago
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I don't see that statistic in the Medscape article. But whatever the risk in the general population, that includes people with and without HPV16, with almost all cases in the latter group. In any case, I suspect you're off ten-fold: cancer statistics usually are expressed per 100,000 population, not 10,000. But the whole point of the article is the statement in large print, from Dr. Gypsyamber Souza, is a highly respected expert in the field: "The data should be reassuring that oropharyngeal cancer remains a rare cancer." Which brings us full circle back to my opening comments and reinforces my comment immediately above about your tendency to absorb and concentrate on what seems bad news. You're missing the forest for the trees. It is exceedingly unlikely you'll ever have this sort of cancer, regardless of your past sexual history. Do your best to suck it up and stop worrying about it.
I hope the discussion has been helpful and allows you to do so!
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