Cancer immunotherapies work by stimulating the body’s immune system and strengthening its natural response to tumor cells. Although immunotherapy has become a promising standard of care for some types of cancer, including liver cancer, its effectiveness can vary widely among patients.
How does liver cancer immunotherapy work?
As the body’s first line of defense against harmful invaders, the immune system usually provides valuable protection from the effects of abnormal cells, such as viruses, bacteria and cancer. However, tumor cells are sometimes able to conceal themselves and avoid detection. For instance, some cancer cells produce a protein known as PD-L1, which binds to the PD-1 ‘off switch’ proteins found on invader-fighting T cells, thereby signaling the T cells not to target and destroy the tumor cells. Immunotherapy for liver cancer most often involves checkpoint inhibitors, which are able to counteract that process by preventing PD-L1 proteins on cancerous cells from binding to the PD-1 proteins on T cells, which in turn allows for a normal defensive immune response against the cancer cells.
Some commonly used checkpoint inhibitor immunotherapies for liver cancer include:
- Atezolizumab (Tecentriq)
- Durvalumab (Imfinzi)
- Pembrolizumab (Keytruda)
- Nivolumab (Opdivo)
- Ipilimumab (Yervoy)
- Tremelimumab (Imjudo)
The unique challenges of treating liver cancer with immunotherapy
The liver filters large volumes of blood received directly from the digestive system and other parts of the body. While performing that vital function, the liver also plays an important role in regulating the immune system. Specifically, the liver determines which of the proteins it encounters are harmful invaders and which should be ignored, then relays that information to the immune system so it can respond appropriately.
Scientists in the medical community have found that some types of liver cancer have unique immune-suppressive capabilities. More precisely, certain liver cancer cells are able to capitalize on the power of the liver to influence the body’s immune response and effectively “convince” it to ignore the tumor. As such, liver cancer may be less responsive to immunotherapy than other types of cancer.
Side effects of liver cancer immunotherapy
Checkpoint inhibitors can cause a variety of side effects, though they vary from person and person— some people may experience significant side effects while others have none at all. Common side effects include:
- Skin rash
- Loss of appetite
- Muscle or joint pain
However, more serious side effects can sometimes occur, including infusion reactions and autoimmune reactions. Infusion reactions are similar to allergic reactions, and can produce symptoms like fever, chills, flushed face, dizziness and trouble breathing. In an autoimmune reaction, the immune system starts attacking healthy parts of the body which, if left untreated, can cause serious problems in the intestines, liver, kidneys, lungs, skin, hormone-making glands and other organs.
Who is eligible to receive immunotherapy for liver cancer?
Immunotherapy is typically used to treat advanced hepatocellular carcinoma (HCC), while early-stage HCC and other types of liver cancer are often treated first with other options. Since immunotherapy can potentially damage healthy liver cells in addition to cancerous cells, it’s not always viable for patients who have histories of hepatitis infections or other liver damage. Unfortunately, since hepatitis causes approximately 80% of all liver cancer cases, immunotherapy may be ruled out for many liver cancer patients. However, there are several other treatment modalities available to fight liver cancer.
Immunotherapy vs. other liver cancer treatments
Immunotherapy works by stimulating the immune system to attack cancerous cells, but other liver cancer treatments work differently:
- Surgery – Based on the size of the tumor, a surgeon may be able to perform a hepatectomy (where a portion of the liver is removed along with the tumor) or a complete liver transplant. Surgery may also include radiofrequency liver tumor ablation, which uses targeted heat to destroy cancerous cells. However, if the cancer has spread throughout the body, surgery may not be effective.
- Radiation therapy – Radiation therapy uses focused energy which can be delivered externally or internally, although external beam radiation therapy is used less commonly since it can affect healthy liver tissue as well as the tumor. Instead, radiosurgery, brachytherapy (internal radiation therapy), or stereotactic body radiation therapy (SBRT) are typically used to treat liver cancer. These treatments are generally painless, though they may cause some side effects that often resolve on their own after treatment is completed.
- Interventional radiology – Minimally invasive techniques such as hepatic artery chemoembolization, radioembolization and percutaneous ablation work by blocking blood flow to the tumor or applying targeted heat or cold to destroy tumor cells.
- Chemotherapy – These powerful drugs are administered orally, intravenously (with an IV) or via injection directly into the tumor. The medications disrupt the growth and reproduction of cancer cells that otherwise would rapidly reproduce, and can shrink previously inoperable tumors to the point where they can be surgically removed.
Moffitt champions groundbreaking advances in immunotherapy for treating liver cancer
As a National Cancer Institute-designated comprehensive cancer center, Moffitt Cancer Center is nationally recognized as a cancer research pioneer. Our scientists and clinicians are continually working to improve liver cancer treatment and discover new options to help each patient achieve the best possible outcome and quality of life. Currently, our patients have access to FDA-approved immunotherapies and other cutting-edge options that are available only through our robust clinical trials program, and we enhance our cancer-fighting arsenal every single day.
If you would like to learn more about immunotherapy and other treatment options for liver cancer, you can rapidly connect with a specialist in the Gastrointestinal Oncology Program at Moffitt Cancer Center. To request an appointment, call 1-888-663-3488 or complete our new patient registration form online. As our patient, you will be a top priority of a cancer center that delivers nationally ranked treatment and supportive care in new and transformative ways.