Immunotherapy for colorectal cancer

Immunotherapy helps to strengthen or restore the immune system's ability to fight cancer. This works to kill cancer cells and stop cancer cells from growing and spreading.

Immunotherapy is sometimes used to treat colorectal cancer. If you have immunotherapy, your healthcare team will use what they know about the cancer and about your health to plan the drugs, doses and schedules.

Immunotherapy may be the only treatment you have or it may be used along with other treatments. You may have immunotherapy to:

• treat and control symptoms of metastatic colorectal cancer
• treat metastatic colorectal cancer that doesn't respond to other treatments or comes back (recurs) after treatment

A type of immunotherapy called immune checkpoint inhibitors may be used for metastatic colorectal cancer.

The immune system normally stops itself from attacking normal cells in the body by using specific proteins called checkpoints, which are made by some immune system cells. Colorectal cancer cells sometimes use these checkpoints to avoid being attacked by the immune system. Immune checkpoint inhibitors are drugs that work by blocking the checkpoint proteins so immune system cells (called T cells) can attack and kill the cancer cells.

Immune checkpoint inhibitors are monoclonal antibodies, which are substances that find and attach to a specific antigen on a cancer cell.

The immune checkpoint inhibitors used for colorectal cancer are ipilimumab (Yervoy), nivolumab (Opdivo) and pembrolizumab (Keytruda). They are used to help shrink and control the growth of metastatic colorectal cancer which has a high microsatellite instability (changes to DNA in the cells). These drugs are given through a needle into a vein (intravenous infusion).

Side effects of immunotherapy will depend mainly on the type of drug or drug combination, the dose, how it's given and your overall health. Tell your healthcare team if you have side effects that you think might be from immunotherapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

Ipilimumab and nivolumab may cause these side effects:

• fatigue
• diarrhea
• skin problems, such as a rash
• headaches
• liver problems, such as yellow skin and eyes
• thyroid problems, which may cause changes in weight, body temperature, heart rate and blood pressure
• lung problems, such as a cough and shortness of breath

Find out more about immunotherapy. To make the decisions that are right for you, ask your healthcare team questions about immunotherapy.

Details on specific drugs change regularly. Find out more about sources of drug information and where to get details on specific drugs.