HPV Above the Waist
Dear Middle School Mom Acquaintance,
When you told me you weren't going to vaccinate your son for HPV, I should have said something. I have excuses - I was distracted at parent pick-up and parenting conversations are already so contentious, what with politics, opinions about kids on social media, and the most fractious topic of all - school lunches. I've been thinking a lot about what I could have said and here's what I'd like to tell you: I'm a pathologist and I know about all the things that can go wrong. You should vaccinate your son because he's at risk for catching an HPV-related cancer.
Human Papilloma Virus (HPV) is not only the cause of cervical cancer, it is also the cause of a relatively new epidemic of oral cancers in young, white men spread by oral sex.
Oropharyngeal cancer is the medical term for cancer of the back of the throat. Rates of these cancers are rapidly rising, with 16,000 new cases every year. Patients are predominately young white men and they share a common risk factor - they are infected with HPV.
There are more than 150 strains of HPV and they behave differently. Most infections go away on their own. Some cause health problems like genital warts. But there is a family of HPV that we call High Risk Types and these are the carcinogenic kind.
Here's what a infected cells looks like:
The virus causes specific, predictable changes in how the nucleus of the cell looks - it’s enlarged and wrinkled (we say “raisinoid” meaning like a raisin).
The virus gets into the nucleus and physically interferes with the cell’s regulatory system. Imagine eliminating the starting monitor at a race – now each car can start whenever it wants to. That’s what happens after HPV barges into the nucleus and knocks out the main cell division regulator, called rather prosaically Rb. Without Rb, the cell starts dividing. The nucleus looks bigger and irregular ('raisinoid'), which reflects the increased activity inside. This is the start of the race that leads towards cancer.
(Photos taken through the eyepiece of a microscope have this appearance, rather like a planet in a telescope).
As the cells divide, they grow and replace the surface lining of the tongue or tonsil, called dysplasia, as shown above.
Without surgical removal these altered cancerous cells will invade down into the muscle of the tongue or other soft tissues of the mouth and neck. Because the symptoms can be subtle, (a rough patch in the mouth or sensation while swallowing), often these cancers are found after they have invaded and spread to a lymph node in the neck (metastasis).
This shows the smear of metastatic cells from a lymph node. This sample was taken by a surgeon or pathologist, and a pathologist evaluated the material during the procedure while the patient was there.
Oral cancer treatment is painful and potentially disfiguring. This is the photo of a typical cancer specimen from the head and neck surgeon.
(Buccal means the inside of the cheek.)
Pathologists carefully label, scrutinize and sample the tissue to make sure we know how big and deep the tumor is. We evaluate the tissue from the O.R. and also under the microscope.
Pathologists know what the tumor looks like and we understand why it behaves the way it does. For example, why is HPV associated specifically with cancers of the cervix, anus and back of your throat? It's because places where the inside of your body meets the outside have increased cell division and are fertile ground for tumors and infections to grow.
Here's where the questions might get awkward at parent pick up*-- just how is HPV infecting the back of the throat? It is a sexually transmitted disease, and sex involves more than genitals. An infected cervix is a rich source of virus and engaging in oral sex can transmit the virus. We all know that more people today engage in oral and anal sex, for whatever reason you favor (it feels good, more access to porn, social media or abstinence-only sex education are all possible reasons). And any doctor can tell you - all orifices are fair game for the curious.
Some parents think that if you vaccinate your child against HPV you are giving them permission to engage in sexual activity. Your values and the experiences you've provided for your child matter far more than any vaccination. And it may be that not talking about sex and not vaccinating your child can backfire - if we teach children that only vaginal intercourse virginity matters, oral sex becomes no big deal and not talked about. Kids have lots of influence from friends that we are not entirely aware of. Frankly, we can't assume that every sexual interaction will be well-thought out; some unfortunately are not even consensual.
Out of all the choices we make on our kids behalf, as a mom and a pathologist, this one was easy for our family. We love our kids, warts and all - but maybe we can spare them some of the warts, and cancers too.
*For an example of how awkward it can get, see Michael Douglas: http://www.businessinsider.com/michael-douglas-says-his-cancer-was-caused-by-oral-sex-2013-6
More information about HPV:
Excellent information for those looking to better understand the risks and disease. www.oralcancerfoundation.org/hpv-oral-cancer-facts/
"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."
HPV-positive oral cancers (oropharyngeal cancers) have shown a significant increase in incidence during the past several decades, in contrast to the decreasing incidence of smoking and alcohol-related head and neck squamous cancers. The absolute number of Head and Neck cancers has fallen, attributed to a drop off in tobacco smoking rates. But within the category of head and neck cancers, the proportion of these tumors attributable to HPV-related cancers has been increasing at about a 2% rate every year between 1973 and 2004. Every year the CDC estimates that there are more than 16,000 cases of HPV- positive head and neck cancer. Vaccination can prevent new infections but there is no cure for an established infection.
There are unanswered questions about HPV in the head and neck: How common is oral HPV infection in the general population? What is the natural history of oral HPV? (most HPV infections clear on their own). Do precancers exist and could we develop a test like the Pap smear to monitor? Why is the incidence of oral HPV associated cancers found in younger men, and not as frequently in women? (Studies involving lesbians are few in number).