Head and neck squamous cell carcinoma and immunotherapy

Immunotherapy is a type of cancer treatment that helps the body’s immune system identify and fight cancer cells. It has been called the “fourth pillar of oncology,” following the three long-established treatment pillars of surgery, radiation therapy, and chemotherapy.

Along with surgery, radiation therapy, and chemotherapy (and targeted therapy), immunotherapy is being used in the treatment of head and neck cancers—more specifically, immunotherapy is being used in the treatment of head and neck squamous cell carcinomas.

What are squamous cell carcinomas? The term head and neck cancer refers to numerous cancers that begin in the nose, sinuses, throat, mouth, and saliva-producing glands. Like other cancers, head and neck cancers begin with the uncontrolled growth of mutated cells.

The majority of head and neck cancers begin in cells called squamous cells—thin, flat cells that line hollow spaces in the body and are also found on the surface of the skin. Cancers that begin with these cells are called squamous cell carcinomas. Head and neck cancers of this type are called head and neck squamous cell carcinomas.

Head and neck squamous cell carcinomas account for roughly 90 percent of head and neck cancers. There are other types of head and neck cancers that are less common.

How does immunotherapy work? Immunotherapies help the body’s immune system fight cancer cells. There are different types of immunotherapies that are used to treat different types of cancers. The immunotherapies being used in the treatment of head and neck squamous cell carcinomas are called immune checkpoint inhibitors.

Immune checkpoints are proteins found on healthy cells. These proteins protect healthy cells from immune cells, which detect and destroy harmful substances like pathogens, foreign substances, and mutated cells.

Some cancer cells also have high amounts of immune checkpoints. These help the cancer cells avoid detection by the immune system, allowing them to continue to duplicate, grow, and spread. In other words, immune checkpoints act as a disguise—cancer cells appear normal to the immune system.

Immune checkpoint inhibitors are drugs that block immune checkpoints, which helps the immune system detect and attack the cancerous cells.

There are several immune checkpoint inhibitors that are FDA-approved for the treatment of head and neck cancers. These medicines block an immune checkpoint called PD-1 and are given by infusion.

To determine if a cancer might respond to this type of therapy, a healthcare team can order laboratory tests that examine a sample of cancerous tissue to look for immune checkpoint proteins. This is known as biomarker testing.

PD-1 inhibitors may be used in combination with other cancer therapies, including chemotherapy.

Should you treat with immunotherapy? Cancer is a different experience for every person—and the decision of how to treat the cancer is one that a person will need to make under the guidance of their healthcare team. Like other cancer treatments, PD-1 inhibitors can cause side effects, and in some cases can cause serious side effects. Potential side effects and what to do if you experience a side effect should always be discussed prior to beginning any treatment.

As a person living with head and neck cancer, it helps to understand the different treatment options and how they work. If you have questions about a particular treatment, your best source of information will be your healthcare team.