Kathryn A. Gold, MD
Head and neck squamous cell carcinoma (HNSCC) consists of 2 biologically and clinically different diseases, according to Kathryn A. Gold, MD. The first of which is carcinogen induced, caused by tobacco or alcohol use, and the second being virally associated through the contraction of the human papilloma virus (HPV).
The recent rise in HPV has directly affected the increase in HNSCC cases, namely oropharyngeal cancer in men. Patients with HPV-positive present with a different set of prognostic factors and symptoms, says Gold, and should be treated with therapies that differ from those used in carcinogen-induced HNSCC.
During her talk at the 2017 OncLive®
State of the Science Summit™ on Advanced HNSCC and Thyroid Cancer, Gold, a medical oncologist and associate professor of medicine at University of California, San Diego Heath, discussed HPV status and prognosis of these patients, as well recognizing risk factors of virally-associated HNSCC. In an interview during the meeting, Gold emphasized the need for differentiated treatment, as well as the realistic opportunity to prevent cancer through vaccination.
OncLive: Can you provide an overview of your presentation on virally mediated head and neck cancer?
In the clinic, we are increasingly recognizing that more of our patients are coming in without the traditional risk factors that we think of for head and neck cancer. Traditionally, we think of head and neck cancer as being a disease of older men and those with tobacco or alcohol exposure. Some of our younger patients do not have any of those exposures. It is becoming increasingly recognized that HPV is the cause of their head and neck cancer.
This seems to be very clinically important. These patients are younger and healthier than our HPV-negative patients and the treatment outcomes do tend to be different, as well.
How should we approach HPV-positive patients differently?
We know that HPV-positive patients tend to have a better prognosis. If a patient who is HPV positive comes in with locally advanced disease, there is a good chance that I can cure their cancer. Right now, we are not using that as a factor to select treatment options, but we will in the future. As we learn more about this cancer, we may be able to dial back a little bit on the treatment for these patients and possibly spare them some of the long-term toxicities that we see with head and neck cancer therapy.
We now know that HPV is prognostic. For patients who come in with locally advanced disease, we typically treat them with chemoradiation—which are the vast majority of patients that I see in my clinic. Chemoradiation of HPV-negative cancer does not have great overall survival; it is only about 40% at 5 years. For HPV-positive cancer—especially nonsmokers—we cure about 85% of those patients so the prognosis is very different. Even for HPV-positive patients, smoking affects this rate. If a patient is HPV positive and they are a smoker, their outcome in a more intermediate category than those who have never smoked.
What are the clinical characteristics that are seen with this population?
The clinical characteristics that we see in someone coming in with an HPV-positive head and neck cancer, firstly, is that the primary site tends to be in the base of the tongue or tonsils, while HPV-negative disease is more likely to be found in the oral cavity, larynx, or hypopharynx. HPV-positive patients also tend to be younger than those who present with HPV-negative. They are usually male; it’s about a 3:1 ratio of men to women with HPV-positive head and neck cancer. Pathologically, these tumors are more likely to be differentiated, non-keratinizing carcinoma.
Can you provide some insight into the treatment of HPV-related oropharyngeal cancer?
Oropharyngeal cancer typically presents locally advanced, meaning with a large primary tumor—or more often, with lymph node metastases. The textbook treatment for these is to combine chemotherapy with radiation, specifically, intensity-modulated radiotherapy with high-dose cisplatin at 100 mg/m2
every 3 weeks. That is our typical treatment, and it leads to good outcomes; however, we also know that it is very hard to tolerate. It can leave people with lifelong swallowing difficulties, dry mouth, and neuropathy. Obviously, if that is the only way to cure the cancer, than most people would say that it is worth it. However, our goal is to cure them with less intensive therapy.