Immunotherapy has been a tool for fighting cancer for decades, but recent advancements are making it more effective and its use more frequent.
“The concept of immunotherapy is to enlist the immune system to fight tumors of any type,” said Dr. Richard Mercier, an oncologist/hematologist at Marshfield Clinic Health System. “The immune system is designed to recognize when there’s something wrong in the body, and you’re trying to help the immune system recognize that abnormality.”
Mercier said researchers have recently discovered tumors have the ability to cloak themselves, in effect hiding from the immune system.
“Current therapies have found a way to remove that cloak, which allows the immune system to recognize cancer cells and identify them as something foreign to the body,” Mercier said.
Immunotherapy comes in several forms
Several variations of immunotherapy can be used depending on the patient’s circumstances.
Bone marrow transplant: Bone marrow transplants from family members or unrelated donors use the donor’s immune system to help fight the patient’s cancer.
Tumor vaccine: Preventive vaccines help the immune system target potential cancer-causing agents in the body. Cancer treatment vaccines work to slow or stop cancer in the body once it’s present.
Immune stimulants: Medications like interferon or interleukin are used to strengthen the immune system although they tend to come with significant side effects.
Monoclonal antibodies: These antibodies can help direct a medication to fight cancer in the body or influence the immune system itself to attack cancer.
Checkpoint inhibitors: This therapy works to wake up the immune system because many cancers produce a protein, which puts the immune system to sleep.
Is immunotherapy effective for every cancer type?
“There is no question immunotherapy is more successful in some cancers than with other cancers,” Mercier said. “In melanoma, for instance, immunotherapies have outperformed traditional chemotherapy.”
Mercier noted that any cancer type is potentially treatable with immunotherapy.
“What we’re finding with checkpoint inhibitors is that sometimes you also unleash the immune system in creating what we call autoimmune problems, where the immune system can attack the lungs, liver and skin,” Mercier said.
The most recent generation of immunotherapy treatments seems to have fewer side effects, though side effects are still a major issue. In general, Mercier said immunotherapy has fewer side effects than chemotherapy.