Immunotherapy to treat cancer

Immunotherapy is an option when your current cancer treatment isn’t working or if your cancer has returned. Understanding how immunotherapy works – and how it applies to your type of cancer – can help you be better prepared for this stage of your cancer care journey.

What is immunotherapy?

Immunotherapy works by helping your own immune system better target cancerous cells in your body. Immunotherapy seeks to improve your immune response to help the body locate and destroy cancer cells even as they change and alter healthy cells around them.

How does immunotherapy work?

The body’s immune system naturally works to detect and destroy abnormal cells. But the unpredictability of cancer cells can make it complicated for the immune system to kill all cancer cells. Immunotherapy works by helping the immune system better detect these changes that might make cancer cells harder to detect and destroy.

Sometimes cancer immunotherapy is used on its own. Other times it's used in conjunction with other cancer treatments such as chemotherapy, hormone therapy or surgery.

How effective is immunotherapy for treating cancer?

How effective immunotherapy will be may depend on the type of cancer, its stage, genetic factors and tumor biomarkers.

Chemotherapy vs. immunotherapy

You and your cancer care team will decide whether immunotherapy, chemotherapy or a combination of the two will be most effective for your circumstances. Immunotherapy is often used when your existing cancer treatment stops being as effective as it was or when cancer cells return and spread.

Types of immunotherapy cancer treatment

There are several types of immunotherapy cancer treatments. Most immunotherapy drugs are given orally through medications taken at home or as an injection or infusion through an IV line into a vein that’s administered in an outpatient setting.

Here’s a look at some of the current immunotherapy treatments being used.

Immune checkpoint inhibitors

While immune checkpoint inhibitors don’t directly kill cancer cells, they do help your immune response target cancer cells in the body. These medications target different “checkpoint” proteins in cells, which helps the body identify which cells are cancerous.

Monoclonal antibodies

Monoclonal antibodies are created proteins that mimic actual antibodies. These antibodies attack cancer cells and kill them.

Adoptive cell therapy

Also known as cellular immunotherapy, adoptive cell therapy takes the T cells that already destroyed cancerous tumors. The cells are activated and expanded before being reinfused. These new white blood cells seek out and destroy tumors.

Cancer vaccines

Vaccines, such as a flu shot or shingles vaccine, are typically administered to help prevent illness by using weakened viruses that prepare the body to fight off an infection. Instead of preventing a disease, cancer vaccines train the body to attack cancer cells already in the body.

Immune system modulators

Immune system modulators are a group of immunotherapy drugs used to treat cancer. They range in form and the way they work. For example, one type of immunotherapy is a liquid put into the bladder using a catheter and used to attack cancer cells.

Immunotherapy side effects

Side effects depend on the type of immunotherapy cancer treatment received. Unlike chemotherapy, where side effects happen during treatment, most side effects for immunotherapy begin months after treatment begins.

Common side effects for cancer immunotherapy may include:

• Fatigue
• Fever
• Chills
• Muscle, joint or back pain
• Nausea or vomiting
• Headache
• Diarrhea or constipation

How often are immunotherapy treatments given?

There are many factors that determine how frequently people receive immunotherapy. Treatments may be given daily, weekly or monthly. Others are given in cycles so the body has time to rest between treatments.

What cancers does immunotherapy treat?

Immunotherapy cancer treatment has proven effective in treating many types of cancers. And research is on-going to see if it’s an effective treatment for other types of cancers. Here are some of the cancers where providers often use immunotherapy as a treatment option.