Immunotherapy 101: What it is and how it’s used to treat cancer

The human immune system is made up of special cells, chemicals and organs that fight infection, which are also known as microbes. It includes white blood cells, antibodies, the complement system, the lymphatic system, the spleen, the thymus and bone marrow. These all work together to fight infection.

The immune system also functions to ward off foreign or altered cells that may become cancerous. Sometimes mechanisms of the immune system fail, perhaps due to genetic predisposition, smoking, excessive alcohol consumption, exposure to chemicals or obesity, which can cause cancer to arise.

Oncologists at the Barbara Ann Karmanos Cancer Institute regularly use immunotherapy to fight cancer. Immunotherapy is a type of biological therapy that uses substances made from living organisms inside the human body to treat cancer. The body’s immune system detects and destroys abnormal cells and most likely prevents or inhibits the growth of many cancers.

"Normally, our immune system is what keeps us free of tumors," said Mohammed Najeeb Al Hallak, M.D., MS, member of the Gastrointestinal and Neuroendocrine Multidisciplinary Team at Karmanos Cancer Institute and assistant professor at Wayne State University School of Medicine. “However, some tumors can inhibit the immune system.”

Immunotherapy can arm a person’s cells to fight cancer tumors.

The types of cancers that immunotherapy helps fight include:

Immunotherapy is a relatively new form of cancer treatment. Clinical trials for the use of various immunotherapy agents began around 2010. There are a variety of immunotherapy methods used to treat cancer, and each immunotherapy agent works on different cellular mechanisms.

Immunotherapy treatments include:

  • Immune checkpoint inhibitors, which are drugs that block immune checkpoints. Checkpoints are a normal part of the immune system and keep immune responses from becoming too strong and harming healthy cells. Checkpoint inhibitors agents include Keytruda ®, also known by its scientific name Pembrolizumab, as well as Opdivo® (Nivolumab), Tecentriq (Atezolizumab) and Yervoy (Ipilimumab). They are also known as monoclonal antibodies, which are immune system proteins created in a lab and designed to bind to specific targets on cancer cells. Some monoclonal antibodies mark cancer cells so that they are more easily seen and destroyed by the immune system.
  • T-cell transfer therapy, which boosts the natural ability of T-cells to fight cancer. T-cells are part of the immune system and develop from stem cells in the bone marrow. They help protect the body from infection and may help fight cancer. During T-cell transfer therapy, immune cells are taken from a person’s tumor. The most active immune cells are selected or changed in a lab to better attack cancer cells. They may also be grown in large batches and then infused back into the body through an intravenous needle. Karmanos was the first cancer center in Michigan and one of the first in the country to utilize a type of T-cell transfer therapy called CAR-T therapy. This procedure is used for diffuse large B-cell lymphoma, an aggressive form of non-Hodgkin lymphoma.
  • Treatment vaccines, which boost the immune system’s response to cancer cells.
  • Immune system modulators, which enhance the body’s immune response against cancer. Some of these agents target specific parts of the immune system, while others affect the immune system in more general ways.

Immunotherapy can be given directly into a vein (intravenously). It can also be a topical treatment (which can be used for very early skin cancer), injected into a muscle, or can be intravesical, where the immunotherapy treatment is administered directly into the bladder.

Dr. Al Hallak said that using immunotherapy confers benefits that a cancer patient doesn’t receive from chemotherapy.

"Immunotherapy can give us a longer survival,” he said. “It helps more patients go into remission. We do not see many of the side effects that can come with chemotherapy. The patients live a more normal life."

Other benefits include:

  • Patients do not have to visit the hospital as often to receive immunotherapy.
  • Patients typically experience a higher quality of life, with fewer side effects.
  • Immunotherapy is better tolerated in most patients.
  • Older patients who may have difficulty undergoing chemotherapy may be a candidate for immunotherapy.

Dr. Al Hallak advises cancer patients to work with their doctors to determine if immunotherapy is right for them.

"It’s really important to test the genetics of your cancer to see if you’re a candidate for immunotherapy," he said.

To learn more about immunotherapy at Karmanos Cancer Institute, please call 1-800-527-6266.

Mohammed Najeeb Al Hallak, M.D., MS