Immunotherapy is a type of cancer treatment that helps your immune system fight cancer. The immune system helps your body fight infections and other diseases. It is made up of white blood cells and organs and tissues of the lymph system.

Immunotherapy is a type of biological therapy. Biological therapy is a type of treatment that uses substances made from living organisms to treat cancer.

Types of Immunotherapy

Many different types of immunotherapy are used to treat cancer. They include:

• Monoclonal antibodies, which are drugs that are designed to bind to specific targets in the body. They can cause an immune response that destroys cancer cells.

  Other types of monoclonal antibodies can "mark" cancer cells so it is easier for the immune system to find and destroy them. These types of monoclonal antibodies may also be referred to as targeted therapy. See Precision Medicine and Targeted Therapy for more information.

• Adoptive cell transfer, which is a treatment that attempts to boost the natural ability of your T cells to fight cancer. T cells are a type of white blood cell and part of the immune system. Researchers take T cells from the tumor. They then isolate the T cells that are most active against your cancer or modify the genes in them to make them better able to find and destroy your cancer cells. Researchers then grow large batches of these T cells in the lab.

  You may have treatments to reduce your immune cells. After these treatments, the T cells that were grown in the lab will be given back to you via a needle in your vein. The process of growing your T cells in the lab can take 2 to 8 weeks, depending on how fast they grow.

• Cytokines, which are proteins that are made by your body's cells. They play important roles in the body's normal immune responses and also in the immune system's ability to respond to cancer. The two main types of cytokines used to treat cancer are called interferons and interleukins.
• Treatment Vaccines, which work against cancer by boosting your immune system's response to cancer cells. Treatment vaccines are different from the ones that help prevent disease.
• BCG, which stands for Bacillus Calmette-Guerin, is an immunotherapy that is used to treat bladder cancer. It is a weakened form of the bacteria that causes tuberculosis. When inserted directly into the bladder with a catheter, BCG causes an immune response against cancer cells. It is also being studied in other types of cancer.

Who Receives Immunotherapy

Immunotherapy is not yet as widely used as surgery, chemotherapy, and radiation therapy. However, immunotherapies have been approved to treat people with many types of cancer.

Many other immunotherapies are being studied in clinical trials, which are research studies involving people. To find a study that may be an option for you, visit Find a Clinical Trial.

How Immunotherapy Works against Cancer

One reason that cancer cells thrive is because they are able to hide from your immune system. Certain immunotherapies can mark cancer cells so it is easier for the immune system to find and destroy them. Other immunotherapies boost your immune system to work better against cancer.

Immunotherapy Can Cause Side Effects

Immunotherapy can cause side effects. The side effects you may have depend on the type of immunotherapy you receive and how your body reacts to it.

The most common side effects are skin reactions at the needle site. These side effects include:

• Pain
• Swelling
• Soreness
• Redness
• Itchiness
• Rash

You may have flu-like symptoms, which include:

• Fever
• Chills
• Weakness
• Dizziness
• Nausea or vomiting
• Muscle or joint aches
• Fatigue
• Headache
• Trouble breathing
• Low or high blood pressure

Other side effects might include:

• Swelling
• Weight gain from retaining fluid
• Heart palpitations
• Sinus congestion
• Diarrhea
• Risk of infection

Immunotherapies may also cause severe or even fatal allergic reactions. However, these reactions are rare.

How Immunotherapy Is Given

Different forms of immunotherapy may be given in different ways. These include:

• Intravenous (IV)
  The immunotherapy goes directly into a vein.
• Oral
  The immunotherapy comes in pills or capsules that you swallow.
• Topical
  The immunotherapy comes in a cream that you rub onto your skin. This type of immunotherapy can be used for very early skin cancer.
• Intravesical
  The immunotherapy goes directly into the bladder.

Where You Go for Your Treatment

You may receive immunotherapy in a doctor's office, clinic, or outpatient unit in a hospital. Outpatient means you do not spend the night in the hospital.

How Often You Will Receive Treatment

How often and how long you receive immunotherapy depends on:

• Your type of cancer and how advanced it is
• The type of immunotherapy you get
• How your body reacts to treatment

You may have treatment every day, week, or month. Some immunotherapies are given in cycles. A cycle is a period of treatment followed by a period of rest. The rest period gives your body a chance to recover, respond to the immunotherapy, and build new healthy cells.

How Immunotherapy Makes You Feel

Immunotherapy affects people in different ways. How you feel depends on how healthy you are before treatment, your type of cancer, how advanced it is, the type of therapy you are getting, and the dose. Doctors and nurses cannot know for certain how you will feel during treatment.

How to Tell Whether Immunotherapy Is Working

You will see your doctor often. He or she will give you physical exams and ask you how you feel. You will have medical tests, such as blood tests and different types of scans. These tests will measure the size of your tumor and look for changes in your blood work.

-NIH