What Is Immuno-Oncology?

Immuno-oncology is the study and development of treatments that take advantage of the body’s own immune system to fight cancer.

What Is the Immune System?

The immune system’s job is to identify and destroy potentially harmful invaders from the body, such as viruses and bacteria that can cause infections. Cells in the immune system are programmed to find differences between foreign cells and our own cells, and to selectively attack the foreign cells.

There are two main parts of the immune system: the humoral (also called antibody-mediated) immune response and the cell-mediated immune response. These two sides work together.

As part of the humoral immune response, B-cells generate antibodies in the blood that help us fight off infections in the lymph or blood, and provide us with lasting immunity to ward off future infections.

As part of the cellular immune response, T-cells identify and destroy cells that are abnormal because they are infected, transplanted, or cancerous. The T-cells recognize these cells as being unhealthy because of the molecular markers (a biological molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, or of a condition or disease) displayed on their surface. Some cancers steal the identity of normal cells to hide themselves from T-cells.

The activity of the immune system has to be carefully balanced: both an overactive and an underactive immune system can be harmful. Our growing understanding of how the immune system keeps its balance is the heart of the field of immuno-oncology that has led to the development of immunotherapies to treat people with cancer.

Immunotherapy to Prevent Cancer—Vaccines

For many years, we have known that cancers are caused by genetic changes. More recently, immuno-oncology researchers have also discovered that chronic inflammation from substances in our environment, like tobacco smoke and viral infections, can promote cancer development.

It’s through this inflammatory process that certain high-risk types of human papilloma virus (HPV) can not only cause genital warts but also lead to cervical, anal, mouth, vulval, and throat cancers. To prevent HPV infection, two vaccines on the market are recommended for use in children 11 to 12 years old. These vaccines are very effective at eliminating the pre-cancerous changes that can lead to the development of cancer through this inflammatory process. These vaccines are great examples of how we can use the immune system to help prevent cancer.

Immunotherapy to Treat Cancer—T-Cell Checkpoint Inhibitors

T-cell checkpoint inhibitors are monoclonal antibodies designed to block the blinders that keep T-cells from recognizing that the cancer cells are abnormal and need to be destroyed. These checkpoint inhibitors help T-cells become stronger and more active so that they can control the cancer.

There are two main classes of T-cell checkpoint inhibitors. One class blocks molecules that hide cancer cells from the immune system. These molecules are called PD-1 and PD-L1. Two drugs in this class—nivolumab (Opdivo) and pembrolizumab (Keytruda)—are approved by the FDA to treat people with melanoma and lung cancer. Two other drugs in this class— atezolizumab (MPDL3280A) and MEDI4736—are in clinical trials.

The other class of T-cell checkpoint inhibitors makes T-cells more active. These inhibitors block a molecule called CTLA- 4. The main job of CTLA-4 is to slow down T-cells. Two drugs in this class are ipilimumab (Yervoy) and tremelimumab. Ipilimumab is FDA approved to treat people with some types of melanoma. Tremelimumab is being tested in clinical trials. Tremelimumab used to be called ticilimumab or CP-675,206.

These immunotherapy drugs don’t cause many of the side effects usually associated with standard chemotherapy, such as lower blood counts, hair loss, or nerve damage. Read the Side Effects of Immunotherapy section (page 7) to learn how to manage toxicities associated with immunotherapies.

Immunotherapy to Prevent Cancer Recurrence

Researchers have tried to use vaccines to prevent cancer recurrence. This approach hasn’t been successful so far but there are still ongoing clinical trials trying to improve on this approach.

One approach that has achieved some response is modulation of the immune response. For example, interferon has been used to delay recurrence in people living with melanoma. However, this treatment is tough on patients and produces a modest benefit in overall survival. To improve on this, clinical trials are ongoing to test the newer active immunotherapies, ipilimumab, and nivolumab, in the prevention of cancer recurrence in very high-risk patients.

How to Manage the Side Effects of Immunotherapy

It’s hard to predict if and when you might experience side effects from immunotherapy. Your health care team will explain the possible side effects and their warning signs for your specific medications. They will also teach you what you should do to take care of yourself. Keep in mind that when identified early, most side effects are easily managed.

Below we describe the most common side effects of immunotherapy. We also suggest ways to prevent and manage them.

Flu-Like Symptoms (Fever, Fatigue, Pain)

Flu-like symptoms and fever are common side effects of immunotherapies. These symptoms often include extreme muscle and whole body aches, especially in the joints. Many people say that they hurt all over.

Medications. Similar to the flu, these symptoms may be managed with rest and medications. During immunotherapy, acetaminophen (such as Tylenol) is the usual first choice drug to treat joint pain and fever. Use of nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen (Motrin and others), and naproxen (Naprelan, Midol, Aleve, and others), should be cleared with your health care team because NSAIDs can reduce the ability of blood to clot.

Rest and Physical Activity. There are other ways to treat fatigue and joint pain caused by immunotherapy. While full rest might seem to be the most logical choice, some degree of movement, especially gentle movements and stretching, can make you feel better. Talk with your health care team to find out exactly how much activity or exercise you should do.

If your primary team is not sure about what activities would help you, ask for a consultation with a physical medicine and rehabilitation specialist. Nearly all accredited cancer centers have experienced professionals who can counsel people coping with a cancer diagnosis. Many centers offer a specialized program called the STAR Program ® (Survivorship Training and Rehab) to help patients integrate exercise, activity, and other physical therapy techniques during and after cancer treatment.

Nutrition. Speak with someone on your health care team about nutritional needs during cancer treatment. Accredited centers have nutritionists or oncology dietitians who can help you sort through what you should and shouldn’t eat during your treatment.

Good nutrition, good activity, and restful periods of time (restorative sleep and rest) will work together to help you during treatment. As long as their use is guided by your health care team, this trio of interventions can boost energy and reduce the pain you might feel during immunotherapy.


Diarrhea is another common side effect of immunotherapies. It can keep people living with cancer at home and disrupt their quality of life. The type of diarrhea varies from person to person and between immunotherapies. In general, individuals experience loose stools that come out rather suddenly and can sometimes cause incontinence.

Stool Bulking Agents. One of the best ways to prevent this type of diarrhea is to keep the stool as solid as possible. This can be done by taking a psyllium type of bulk laxative (Metamucil and others) commonly used to treat constipation. Taking this powder in a more concentrated form than what is used for constipation can help absorb water in the stool. Ask your health care team for instructions.

Anti-Diarrheal Medications. Many people use the anti-diarrhea medication loperamide (Imodium and others) which is sold in tablet and liquid form. Some people find that if they take the tablets, their stool binds up for a short time and then it alternates between liquid stool and hard stool.

If you use the liquid form, start with a very small dose and take a few drops throughout the course of your waking hours. This way you will achieve better control of your bowels during the day.

Talk With Your Health Care Team. Notify your health care team about any diarrhea symptoms. Don’t be afraid to speak up. Some people worry that if they report side effects, their treatment doses will be cut or stopped. Sometimes this is necessary. But most of the time, there are interventions that will help you and your team maximize your quality of life, and stay on treatment as long as possible to get the most benefit.


About 20 to 30 percent of people on immunotherapy develop side effects that affect the skin. The most common of these is a rash that looks like measles. This rash can be itchy and affect some people’s ability to sleep.

In some cases, these side effects may indicate that these drugs are working against your cancer. However, keep in mind that people who don’t develop any side effects can also benefit from these drugs.

Medications. The rash and itching can be treated with prescription-strength medications that are applied directly onto your skin or taken as tablets. The two main classes of medications are antihistamines, which are drugs used for allergies, and corticosteroids, which are drugs that act against inflammation.

In most cases, once you start treatment, the rash and itching will improve so that you can continue to receive your therapy.

Dry Skin

Dry skin is another dermatologic side effect of immunotherapies. To prevent and treat dry skin, take brief showers or baths and use fragrance-free soaps and laundry detergents. You should also limit your exposure to the sun. Use these important tips:

  • When you go outside, don’t leave your skin unprotected. Wear a broad-brimmed hat, sunglasses, and protective clothing, especially between the hours of 10 a.m. and 2 p.m., and at all times during the summer.
  • Apply a broad spectrum sunscreen with a 30 or higher sun protection factor (SPF).
  • Reapply sunscreen every two hours, or every hour if swimming or sweating.

Changes in Skin or Hair Color

Some individuals treated with immunotherapies experience changes in skin or hair color. Patches of skin lose color or hair becomes grayer during treatment. It’s very important that you notify your doctor or nurse if you experience any of these side effects.

Frequently Asked Questions

Q. Can immunotherapies attack a diagnosis like chronic lymphocytic leukemia (CLL) that is present in the immune system?

A. Hematologic cancers (cancers found in blood cells) such as CLL, lymphomas, leukemias, and myeloma affect immune cells. There are ongoing studies of immunotherapies for the treatment of patients with these diagnoses. Allogeneic stem cell transplant is also a type of immunotherapy since one of its goals is to allow the transplanted immune system to attack any residual cancer. There are also data of immunotherapy in Hodgkin disease that appear promising. Ask your physician if immunotherapy might have a role in your specific situation.

Q. Are there any immunotherapies to prevent recurrence in estrogen receptor/progesterone receptor-positive breast cancer survivors?

A. While there are no approved immunotherapies for breast cancer, there are ongoing clinical trials of agents targeting the immune system in patients with this diagnosis. Talk with your health care team to see if there are any trials that might be suitable for you.

Q. I’m worried about how the side effects from my treatment will interfere with my summer vacation. Any suggestions?

A. Emotionally and physically, people often need a break. Sometimes the treatment can be timed in such a way that you can get your enjoyment in and at the same time maintain your regimen. Speak with your oncologist to discuss your situation.

Q. How should I plan for continuing with oral medications when I go away on vacation or a long-weekend?

A. Some drugs should not be left at room temperature because this could cause the medication to become less effective, or the capsules might melt. The most important thing to do before you go anywhere is to speak with your doctor or your pharmacist to find out if there is any specific kind of preparation needed to maintain the effectiveness of your drug.

Q. My dad is elderly and is scheduled to start lung cancer treatment. Because of his age, we are concerned about his ability to tolerate side effects. What do you suggest?

A. What is important, rather than age, is the patient’s level of activity or performance status. Share your concerns with the physician and make clear your father’s level of activity. For example, is your father staying in bed more than 75 percent of the day or is he going through his normal activities during the day? Keep in mind that it’s possible that any weakness, fatigue, or poor appetite due to the cancer could improve with treatment.

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This activity is supported by AstraZeneca, Bristol-Myers Squibb, Genentech, and an independent educational grant from Merck & Co., Inc.

Last updated May 16, 2016

The information presented in this publication is provided for your general information only. It is not intended as medical advice and should not be relied upon as a substitute for consultations with qualified health professionals who are aware of your specific situation. We encourage you to take information and questions back to your individual health care provider as a way of creating a dialogue and partnership about your cancer and your treatment.

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