Angela L. Mazul, PhD, MPH, joined the Department of Otolaryngology-Head and Neck Surgery a year and a half ago as a dedicated cancer epidemiologist specializing in head and neck and HPV-associated cancers. She was the sole presenter for the Eye & Ear Foundation’s August 12th webinar, “The Who and Where of Head and Neck Cancer.”
What is Epidemiology?
This field became a big thing during the COVID pandemic. It is the study of diseases, or the disease state. What causes a disease? What are the risk factors? How can it be prevented? How can it be kept from worsening?
An important thing to keep in mind is that statistics are not always perfect; there is never a 100% association in epidemiology.
Head and Neck Cancer (HNC) Incidence
HNC incidence is increasing in the U.S. Dr. Mazul described it as cancer from the lips down to the throat, like the larynx and voice box. She was drawn to it due to its complexity and location.
“Here I am, giving a talk, speaking to you using my tongue and voice,” Dr. Mazul said. If you get cancer in this region, it is difficult to speak. The same with eating – if you cannot speak or eat, it can cause a lot of problems.
There are 71,000 people in the U.S. diagnosed with HNC. About 16,000 will die of it in 2024. The remaining people will have to live with a lot of the problems that result from it.
Cancer Continuum
The Cancer Control Continuum breaks cancer into six discreet blocks: etiology, prevention, detection, diagnosis, treatment, and survivorship.
Etiology is the cause of disease. With HNC, three main things can cause big things: smoking, alcohol, and HPV.
About 72% of HNC are thought to be caused by either smoking or alcohol. People who smoke have 5-25% greater risk of HNC compared to someone who does not smoke. Drinking increases risk to a smaller extent. If done together, risk is definitely increased.
HPV is causing a dramatic spike in HNC incidence. Oral pharynx cancer, cancer of the throat, really changed the face of HNC, Dr. Mazul said. People with HPV+ oral pharynx cancer do tend to survive longer, but there are more people being diagnosed. It has overcome cervical cancer as the number one type of cancer caused by HPV.
One big way to prevent HNC is HPV vaccination. Unfortunately, vaccination rates are not great. The type of HPV that causes oral pharynx cancer, however, is covered with the Gardasil vaccination.
Great detection methods for HNC do not exist. The earlier cancer is diagnosed, the easier it is to treat. While dentists do screenings of the mouth, patients have to go there to receive them. Access becomes an issue.
Because HPV+ cancer is becoming more common, screening is occurring with blood tests. Based on results, you can potentially find out if you are higher risk and be followed to see if cancer will develop. This is an area of research that is moving quickly. Hopefully there will be a screening soon and therefore early detection.
There is also ongoing research to determine why it is more common to have HNC in developed countries. HPV+ cancer is very common in Europe and the U.S., for example, and less common in Africa and South America. Nasal cancer (the nose area in the back of the throat where the nose meets the throat) is more common in Asian countries.
Diagnoses come about in different ways. Some patients might go to the doctor because there is something weird in their mouth or a lump in their throat. They go to their primary care physician, which means making an appointment, having that appointment, and then getting a referral. If you do not see a PCP annually or regularly, and do not get the issue looked at, then a diagnosis might take longer, and the stage will be higher.
Treatment is complicated. There is a clinical stage determination, then surgery, radiation, and chemo. Three doctors are involved just for treatment. Timing is important. Ideally, surgery occurs six weeks after diagnosis, with chemo and radiation within six weeks of that.
If you do not adhere to these timelines, there is evidence that your survival is highly impacted. Dr. Mazul did a study a couple of years ago where she found that with adherence, survival is much higher. It is still low, probably around 70%, but without adherence and taking a long time to complete radiation, less than 50% may survive.
HNC treatment involves radiation to the throat, which can result in trouble swallowing and speaking. Surgery can mean parts of the tongue or jaw are missing. Lots of physical, occupational, and speech-language therapy can help patients return to life as they knew it. They are more likely to have other outcomes, like stroke or heart attack. Survivorship includes working with the PCP to make sure treatment does not degrade quality of life too much.
“At Pitt, we have one of the best survivorship clinics out there, and it is what really drew me here,” Dr. Mazul said. “Dr. Nilsen and Dr. Johnson run it and do a fantastic job.”
The Who and Where of HNC
Dr. Mazul thinks about disparities when it comes to HNC – not just in who gets it, but their survival and treatment. It is all uneven and based on who you are and where you live – part of the social determinants of health. People who live in rural areas, for example, have issues with transportation. “How do we measure these almost unmeasurable things?” Dr. Mazul asked. “That’s what makes me so excited about epidemiology. We study humans, and humans are complicated. We study these things that aren’t measurable in my lab.”
One of the risk factors for HNC – smoking – has been declining in the U.S. but is still somewhat uneven. Smoking rates are not decreasing evenly across all populations. So, when it comes to smoking cessation and other interventions, specific populations have to be taken into account.
The Centers for Disease Control and Prevention has a social vulnerability index with four metrics: socioeconomic status, household characteristics, racial and ethnic minority status, and housing type and transportation.
Dr. Mazul did a study on larynx cancer with Dr. Sandra Stinnett, who is a laryngologist in the Department. Neighborhoods that are poor, with a very high social vulnerability index, have a high incidence of larynx cancer, which falls in line with the high areas of smoking. More resources need to be poured into these counties to help with diagnosis and smoking cessation. Dr. Mazul is working on getting Western Pennsylvania data and is hoping to focus on a smaller neighborhood in Western PA next year.
HPV vaccination rates for adolescents is also not great; there is lots of work to be done.
Dr. Mazul is working with the VA to see if there are ways to bolster vaccination among veterans. Everyone who seeks care at the VA has access to it and does not need to pay. States with the biggest population do not have high rates of HPV vaccinations.
Oral cavity cancer is increasing among white and low socioeconomic status people. Among Hispanic and Black populations, it is not decreasing quickly but is going down. For the high socioeconomic Black population, it has kind of plateaued, and with Asians, it is the inverse. Dr. Mazul wants to find more data. Why do high socioeconomic Asian populations have higher rates?
A study Dr. Mazul did with Dr. Evan Cordois looked at social vulnerability as well as an area index – rich neighborhood vs poor, measuring how much people are adhering to treatment. In a rich neighborhood, people are more likely to get to treatment on time. If in a poor neighborhood, they are less likely to get to radiation on time. And when you start radiation is highly dependent on where you live. Why is this happening? “We can’t change where someone lives,” Dr. Mazul said. She is submitting a grant soon to study stress. If people are more stressed, they may be less likely to push to get things done on time. If someone is poor, food insecure, with no place to live, a diagnosis will tip them over the edge.
Dr. Mazul is also doing a study with Dr. Nilsen and her postdoc Mariana, a first-year intern in the Department, looking at people who do not come to the Survivorship Clinic. People who live within the Pittsburgh area are more likely to come to the clinic than people who live further away. Forty percent of HNC patients come to the clinic. They want to change this. Dr. Nilsen and Dr. Mazul have submitted a grant to study who is coming. The plan is to talk to these patients – both people who come and those who do not – to figure out what they can do to help HNC patients come to the clinic to really improve their life. Dr. Nilsen has already shown that if they come, they are more likely to regain their speech and happiness, among other things.
Ongoing and Future Studies
- Diabetes and the risk of oral cavity cancer
- Access to ENTs in PA (looking at wait times)
- Psychologic stress in HNC outcomes
- Clinical trial enrollment at Hillman Cancer Center (testing suspicion that people who enroll tend to be wealthier and more urban; are the many rural patients in Western PA coming?)