Immunotherapy for the Treatment of Cancer: What Is it and How Does it work?

Cancer has traditionally been treated with surgery, chemotherapy and radiation therapy. But these treatments are often accompanied by painful side effects and, in addition to killing cancer cells, some of these treatments also kill the body’s healthy cells. 

Researchers have been dedicated to finding new cancer treatment options that can be used in combination with traditional cancer treatments or alone. Immunotherapy, also called biologic therapy, is a relatively new treatment option for cancer patients that helps the body’s immune system kill cancer cells. What exactly is immunotherapy and how does it work? First, it’s important to understand how the body’s immune system works.

The Immune System Protects the Body From Harmful Infections, Even Cancer

Infections and illnesses can occur from bacteria, viruses, other microorganisms like parasites, and even genetic mutations. The immune system recognizes harmful substances that can make a person sick by identifying specific structures on the cell surface, called antigens. All cells have antigens, but the antigens on the body’s healthy cells are different than the antigens found on the cells of harmful substances. When the body recognizes a harmful cell, it sends special immune cells, called T cells, to attack it. There are many different types of immune cells that all work together to identify and attack threatening substances in the body. 

The immune system is capable of identifying cancerous cells and fighting against them. But cancer cells can mutate and change in a way that makes them undetectable by the immune system. When this happens, cancer cells can divide and reproduce at a very fast rate. 

How Does Immunotherapy Treat Cancer?

Immunotherapy works with the body to restore a compromised immune system or to modify and strengthen a healthy immune system to help it identify and kill cancer cells. 
Immunotherapy can work in a few different ways:

Immunotherapy works with the body to restore a compromised immune system or to modify and strengthen a healthy immune system to help it identify and kill cancer cells.

  • Cancer vaccines: Expose the body to antigens associated with certain types of cancers, so that the immune system can easily identify threatening cancer cells and destroy them. 
  • Monoclonal antibodies and tumor-agnostic therapies: Monoclonal antibodies attach to cancer cells to help the immune system identify them. Tumor agnostic therapies help the immune system to identify tumors throughout the body that have the same mutation. 
  • Non-specific immunotherapies: Given at the same time as other cancer treatments. Non-specific immunotherapies stimulate and strengthen the overall immune system, instead of focusing on one specific type of cell.  
  • T-cell therapy: T-cells are special kinds of immune cells. With T-cell therapy, the patient’s T-cells are isolated from a blood sample, altered in a laboratory so that they can identify cancer cells, and are then placed back into the body.  
  • Oncolytic virus therapy: Uses genetically modified viruses that attack cancer cells, but leave the patient’s healthy cells unharmed. 

Although there are numerous different types of immunotherapy, the result of each one is the same—a restored or improved immune system that is better equipped to fight cancer cells.

Can Immunotherapy Be Used to Treat All Types of Cancer?

Immunotherapy is currently used to treat many types of cancer, like breast cancer, skin cancer, and colorectal cancer, but it is not yet available to treat all types of cancer. Scientists continue to develop and research immunotherapies to be able to treat as many cancer patients as possible. 

The Future of Immunotherapy

Today, immunotherapy is mostly given by intravenous infusion or by injection. Less commonly, an immunotherapy that can be administered as a pill and, in the case of skin cancer, as a cream. However, new advancements in research show that, in the future, all immunotherapies might have the potential to be administered as a pill, significantly simplifying the treatment process and improving the patient experience.