Subcutaneous immunotherapy for liver cancer

Liver cancer is cancer that originates in the liver. Like other cancers, liver cancer begins when healthy cells undergo changes (mutations) and begin to grow in an uncontrolled way. The majority of liver cancers (approximately 90 percent) are hepatocellular carcinoma (HCC), which begins when cells called hepatocytes undergo cancerous mutations. Hepatocytes are the main cell type in the liver.

HCC is frequently associated with cirrhosis, damage and scarring to the liver. However, approximately 1 in 4 people with HCC have no history of cirrhosis or cirrhosis risk factors like viral infections (hepatitis B or C), fatty liver disease, or a history of heavy alcohol use.

Treatment for HCC can include local treatments like surgery or procedures to destroy specific tumors. It can also include systemic treatments like chemotherapy, targeted therapy, and immunotherapy—treatments that act on cancer cells throughout the entire body.

Immunotherapy refers to cancer therapies that help the body’s immune system detect and destroy cancer cells. Below is a closer look at how immunotherapies treat HCC, and a look at immunotherapies that can be delivered with subcutaneous injections.

Staging and treatment decisions

HCC is staged differently than other cancers. Several staging systems exist, but none have been universally adopted. Treatment decisions for HCC are guided by several factors and considerations, including:

• If the cancer can be removed by surgery
• If the cancer has spread beyond the liver
• If the cancer has come back after previous treatment
• If the person being treated is eligible for a liver transplant
• The overall health and functioning of the liver
• The size, number, location, and spread of tumors, and if tumors have invaded (grown into) major blood vessels

Immunotherapy is typically used in the treatment of HCC that cannot be removed with surgery or advanced HCC that has metastasized (spread) from the liver to other parts of the body.

Immune checkpoint inhibitors

Immune checkpoints are proteins found on the surface of cells. Under normal circumstances, the presence of immune checkpoints helps prevent the immune system from attacking healthy cells and damaging healthy tissues.

In some cases, cancer cells can produce large numbers of immune checkpoints. For cancer cells, immune checkpoints essentially act as a disguise, helping the cancer avoid detection from the immune system. This enables cancer cells to grow and multiply without being destroyed by the immune system.

Immune checkpoint inhibitors are drugs that disable specific immune checkpoints. This helps the immune system detect and attack cancerous cells, which can shrink tumors and prevent cancer from spreading. Immune checkpoint inhibitors may be used in combination with other cancer treatments.

Intravenous and subcutaneous administration

Most immunotherapies are delivered with intravenous (IV) infusions, infusions that are delivered into the bloodstream using a needle and catheter inserted into a vein.

Medical researchers are always looking for ways to evolve cancer treatment. This includes new therapies and new ways of administering therapies. Subcutaneous immunotherapy is a newer option that is being used in the treatment of HCC and several other types of cancer.

Instead of an infusion into a vein, subcutaneous immunotherapy is injected into the subcutaneous layer, a layer of fatty tissue located just below the skin. From the subcutaneous layer, immunotherapy will be absorbed into the lymphatic system and make its way to cancer cells throughout the body. Subcutaneous immunotherapy injections are typically given in the thigh or abdomen.

The route of administration does not change how an immunotherapy works, only how the drug moves through the body.

Potential benefits of subcutaneous immunotherapy

People with cancers like HCC must attend regular appointments to receive treatment. One goal in the development of subcutaneous immunotherapy is to make drugs like immune checkpoint inhibitors more accessible, easier to use, and less stressful.

Subcutaneous immunotherapy can reduce travel time and appointment time:

• Subcutaneous injections of immune checkpoint inhibitors can be administered at a healthcare provider’s office, meaning they do not require visiting an infusion center or a hospital (which is necessary when receiving an IV infusion).
• A subcutaneous injection typically takes between 3 and 7 minutes to administer, a much shorter time than IV infusions, which can take between 30 and 90 minutes.

These can be important benefits for anyone who does not have easy access to an infusion center or hospital, or who wants to reduce the amount of time they spend in healthcare appointments.

As with any cancer treatment, subcutaneous immunotherapies will be a good treatment option for some people, while other treatment options will be recommended for others. Only a few subcutaneous immunotherapies are available for the treatment of HCC, but the number is expected to expand in the future.

If you have questions about treatment options, your healthcare provider will be your best source of information.