Human papilloma virus (HPV) just became a bit more disconcerting, especially if you happen to be in a particular *cough* industry. A group at Johns Hopkins just reported in the New England Journal of Medicine that risk of a rare throat cancer (oropharyngeal squamous-cell carcinoma)was 9 times higher for people who reported oral sex with more than six partners.
HPV is becoming well known as the virus which causes the majority of cervical cancer cases, and is also the center of a controversial vaccine which conveys immunity to several of the most dangerous HPV strains. The strain of HPV responsible for throat cancer seems to be HPV16, which is one of the strains covered by the vaccine.
The Johns Hopkins study took blood and saliva from 100 men and women newly diagnosed with oropharyngeal cancer which affects the throat, tonsils and back of the tongue.They also asked questions about sex practices and other risk factors for the disease, such as family history.
Those who had evidence of prior oral HPV infection had a 32-fold increased risk of throat cancer.
HPV16 - one of the most common cancer-causing strains of the virus - was present in the tumors of 72% of cancer patients in the study
This figure shows representative cases of oropharyngeal squamous-cell carcinoma. (A) and (C) are cancerous and are stained with hematoxylin (stains nuclei) and eosin (stains cytoplasm). (B) and (D) show HPV-16 through in situ hybridization of viral signals within the tumor cells (indicated by brown dots.)
Furthermore, drinking and smoking did not exacerbate the risk of throat cancer in these patients---it was really *just* the virus. Despite this increased risk, the overall risk even for people who carried HPV, was very low. Its also important to note that the number of patients in the study was low (100 cancer patients, 200 normal controls) so the results should be replicated before you make...er....adjustments in your lifestyle.
It would extremely interesting to determine if the HPV vaccine can also protect against oropharyngeal cancer as well as cervical cancer. Hopefully, this lab or another is working on detmining that.
Interesting side note: the authors also pointed out that, "Poor dentition, infrequent toothbrushing,and infrequent dental visits have been associated with an increased risk of squamous-cell carcinomas of the head and neck." Wow! Not brushing your teeth increases your risk of cancer?! I'm going to brush them right now!
Source:
D'Souza et al. 2007. Case-Control Study of Human Papillomavirus and Oropharyngeal Cancer. New England Journal of Medicine. 356: 1944-56.
Comments
The oral hygiene issue with head and neck cancers is an interesting one; there have been several studies that suggest that some oral bacteria metabolize, for example, alcohol or other carbon sources, and produce assorted carcinogens. And HPV is already known to cause head and neck cancers (and yes, researchers are looking at the vaccine for those as well), so throat cancer is another logical step, I guess.
Posted by: Tara C. Smith | May 10, 2007 7:10 PM
Shelley, this report is old news to oncologists - we've known for some time about the association between putting HPV-infected body parts in one's mouth and the risk of developing squamous-cell carcinoma of the posterior pharynx. Here is an excerpt from a 1998 article from the Hutch that concludes the following:
"Among males only, oral SCC risk increased with self-reported decreasing age at first intercourse, increasing number of sex partners, and a history of genital warts."
[Reference: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=abstractplus&db=pubmed&cmd=Retrieve&dopt=abstractplus&list_uids=9811312]
In fact, smokers who get SQCCA of the posterior pharynx have a better prognosis than non-smokers, presumably because of the effect of HPV on treatment outcomes.
Good oral hygiene truly is important - Mom was right after all!
Posted by: The Cheerful Oncologist | May 10, 2007 8:42 PM
Gardasil, the HPV vaccine, does cover HPV-16 - in theory, the vaccine should protect against the strain no matter where the body contacts it.
I know that this was just a small preliminary study, but I'd love to see more information - I wonder if the rate of infection varies by the gender of the HPV-infected partner. A further question would be whether this info has any health implications for the gay/lesbian community. Inquiring minds... ;)
Posted by: Sara | May 10, 2007 8:56 PM
The explanation on the H&E stain was a nice touch...you're the coolest nerd ever.
Posted by: Biomed Tim | May 10, 2007 10:28 PM
So, is teeth brushing helpful for everyone, or just those people who engage in viral-friendly oral activities?
Posted by: Lab Lemming | May 11, 2007 7:36 AM
I think a more in-depth study is needed, and I volunteer to be a receiver as part of the control group. Anything for Science! A Nobel and a BJ... it does NOT get any better than that!
Posted by: J-Dog | May 11, 2007 1:54 PM
What kind of sex is recommended then?
Posted by: Vanessa Somerville | May 11, 2007 2:35 PM
Vanessa said: "What kind of sex is recommended then? "
Yeah... Vanessa and I would like to know!
Posted by: J-Dog | May 11, 2007 2:40 PM
So, is teeth brushing helpful for everyone, or just those people who engage in viral-friendly oral activities?
I'm sort of puzzling over the question of what oral activities *wouldn't* be virus-friendly.
Posted by: Charlie (Colorado) | May 11, 2007 3:55 PM
Wait, what if I take a shower right after...?
Posted by: Nick Anthis | May 11, 2007 5:37 PM
What kind of sex is recommended then?
The authors failed to mention this in the discussion. How that glaring omission made it past the editors, well I just don't know.
Wait, what if I take a shower right after...?
I think that only works if you're a high-level African health official, speaking in reference to your HIV positive girlfriend.
A Nobel and a BJ... it does NOT get any better than that!
How about a Nobel, a BJ, and a Nature paper?
Posted by: Shelley | May 11, 2007 6:29 PM
"How about a Nobel, a BJ, and a Nature paper?"
Of course, to be rigorous, we would have to also test the effects of cunnilingus. Women are already underrepresented in science as it is!
Posted by: Tyler DiPietro | May 11, 2007 10:52 PM
Wait, I thought oral "sex" wasn't sex!
Posted by: 1inguist | May 12, 2007 12:52 PM
What do they use as a placebo BJ?
Posted by: Lab Lemming | May 13, 2007 7:48 AM
We should all form a prayer chain for Monica Lewinsky.
Posted by: Bob Abu | May 13, 2007 7:27 PM
Isn't it safe if none of the guys have a diseased dick?
Posted by: Bob Abu | May 13, 2007 7:29 PM
I had tonsil cancer.
My treatment finished three years ago. The legacy of radiotherapy on my neck, mouth, throat and jaw is that all are full of scar tissue. The idea of radiotherapy for my type of cancer is to create so much scar tissue that the blood vessels feeding the cancer cannot penetrate the said scar tissue, and so the tumor starves.
So the scar tissue now prevents my mouth from opening more than and inch or so, swallowing food is difficult because the 'swallowing' muscles are scarrified ( is that a real word? ) and my production of saliva is now about 10% of normal, tho for the first two years after treatment I had zilch in the way of saliva.
Anyways, one of the inventors of the vaccine for cervical cancer has said that a spin-off of the vaccine may be to also prevent squamous cell cancers in the head and neck.
Interestingly, John Wilkins of http://scienceblogs.com/evolvingthoughts/ had a finger amputated after it was infected with HPV.
It would be very kind of people not to enquire of me about my oral sex life, nor to speculate about how John's finger became infected.
Cheers.
Posted by: grasshopper | May 20, 2007 9:38 AM
Grasshopper, sorry to hear about your cancer, sounds just awful. I hadn't ever heard of that type of treatment, aka "starving the tumor." Makes good sense but sounds like it has less than desireable after-effects. Thanks for sharing your story.
Posted by: Shelley | May 21, 2007 2:06 AM
At first, I misread that as "porn stars take head", which was probably your intention...
...of course, it's a serious issue, with a catchy headline. Who these days isn't going to read a blog story that mentions porn? But, it's not just those in the "industry" who need to worry is it? Sexual promiscuity and accompanying disease is on the rise, by all accounts. This work simple adds another layer to the issue (another layer that obviously isn't being added by those who indulge, of course)
db
Posted by: David Bradley | May 25, 2007 2:47 PM