[Question #421] Hpv throat cancer connection

34 months ago
Hi doctors. I have been getting conflicting information from local doctors and was wondering if I could get the real facts from you please. 
 My doctor tells me that hpv that causes throat cancer has nothing to do w alcohol or tobacco use but when I read the cdc website it indicates there is definitely a connection. Was wondering if one of them has outdated info. 
 Was also wanting your opinion on my chances of developing throat cancer since my wife was treated for precancerous cells about 10 years ago and at the time I was regularly performing oral on her. I am a non smoker or drinker. 
 Lastly if cancer does developer due to hpv is it ever as far down as the Adam's apple or would always be visible by a dentist or family doc?
 Thank you for the help!
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
34 months ago
Welcome to the forum. Thanks for your question.

There's been a lot of media attention in the past few years to oral cancers from HPV, and it has also been discussed on this forum. Use the search function to look for "throat cancer" or perhaps "oral HPV" and other terms to see other threads and perhaps more detailed replies. But I'm going to take the opportunity now for a blog-like reply that can serve as a summary for other questions in the future. Maybe more information than you are looking for, but I hope you'll bear with me and find it interesting.

A few main points:

1) It is really only one type of HPV (type 16) that causes almost all throat cancers from HPV.

2) Although you will see reference to "oral", "oral and throat", or "head and neck" cancers, in fact the only HPV related problem -- and the only one generating all the news stories -- is cancer of the pharynx, often originating in the tonsils. Other oral cancers generally are not HPV related.

3) It is true that pharyngeal (throat) cancer due to HPV 16 is on the rise, perhaps due in part to more frequent oral sex in recent decades. However, it remains a rare disease -- far less common than cancers like breast, lung, colon, prostate, and others.

4) Oral HPV, and in particular oral infection with HPV 16, is not rare -- a lot less common than genital, but still pretty common. But probably oral HPV is not related entirely to oral sex. Some infections probably are acquired by autoinoculation (i.e. self transfer to the mouth from genital infection) or by oral exposure to partners' genital fluids without direct oral sex exposure. There is no evidence that avoiding oral sex reduces most persons' risk of future pharyngeal cancer caused by HPV.

5) Although oral HPV 16 is not rare, most oral HPV 16 infections do not lead to cancer. Same as in the cervix, where the large majority of HPV infections clear up and never cause cancer, even if never diagnosed or treated.

Now to your own questions:

a) To my knowledge, the association of HPV 16 pharyngeal cancers with alcohol and smoking still is unclear. HPV 16 clearly can cause cancer in nonsmokers with limited alcohol intake. However, the risk may be still higher in presence of those risk factors. Non-HPV associated oral, pharyngeal, and esophageal cancers definitely are associated with alchohol and tobacco use. (I stress I'm not an expert on this. But I would put a lot of faith in the CDC; their opinion probably is more valid than either mine or your own doctor's.)

b) My general comments above address your concern about risk because of oral exposure to your wife and her history of an abnormal pap smear. You don't know that her infection was HPV 16, but even if it was, your risk of pharyngeal cancer is no higher than that of any average male your age -- meaning an extremely low risk.

c) The pharynx ends at about the level that is easily visible. The most reliable examiner probably is your dentist, most of whom these days are aware of increased attention to pharyngeal cancers. You could mention it to your dentist; and also your doctor whenever you have a routine medical exam.

All in all, you should find all this reassuring. I hope it has been helpful. Best wishes--

HHH, MD
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H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
34 months ago
I should have included point no. 6 in my opening comments:  The HPV vaccines protect against HPV 16, and almost certainly will prevent pharyngeal cancer due to it. It's another reason that all young persons should be routinely immunized against HPV, preferably with Gardasil-9. We can expect a major decline in frequency of pharyngeal cancer as the years go by and more and more people are immunized against HPV.

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34 months ago
Wow. Great response! Thank you. 
 I will try not to exasperate you w too many follow ups.
 I didn't know that only type 16 was associated w throat cancer. When my wife had her treatment we had no idea it was hpv therefore she was not tested for a type. We were told they were precancerous cells and a freezing process was done. I guess there is no way we would ever determine what type she had. One treatment seems to have cleared her for good. 
 Lastly it may be impossible but I was wondering if u could put a figure on the odds of someone in my situation contracting throat cancer. I'm 40 yrs old. ( I'm a cpa. I like to put things in terms of numbers if possible. ) thank you again. 
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
34 months ago
Here's are data from CDC on the national rate of oropharyngeal cancer related to HPV:  http://www.cdc.gov/cancer/hpv/statistics/headneck.htm

As you will see, the rate is highest in men, probably because men who have sex with men have the most oral sex and highest overall risk. The rate in heterosexual men probably is similar to that in women, i.e. 1-2 cases per 100,000. I hope you'll agree that's a pretty reassuring statistic Even if you adjust that rate for guesstimates of the number of people who have known HPV 16 oral infection somewhere along the line, maybe their risk is 10 times higher. That would mean 10-20 per 100K, still very low by any standard. And I'll remind you that you only know your wife had an abnormal pap. The chance it was HPV 16 probably is under 10%. So I guess I would put your risk of pharyngeal cancer from HPV 16 at something like 1-5 per 100,000. You could go online to see how these rates compare to more common cancers, which are the ones you should worry more about.

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34 months ago
Amazing! Thank you. I am satisfied and willing to end this. 
If I think of more questions I'll write in again sometime. 
Thanks again. You are a very patient man
Terri Warren, RN, Nurse Practitioner
Terri Warren, RN, Nurse Practitioner
34 months ago
Could I just say, as one of the board experts, I learned a whole lot from your post, Hunter and am grateful to have such a thorough review as a reference.  Thank you.

Terri Warren
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H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
34 months ago
Thanks to both for your kind comments.


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