Biological therapy uses natural or artificial substances that act like (mimic) or block natural cell responses to kill, control or change the behaviour of cancer cells. It is also called biotherapy or biological response modifiers (BRMs).
Although biological therapies have been used for many years to treat other diseases, their use in treating cancer is still relatively new. Biological therapies are used to:
Biological therapy works by stimulating, boosting, restoring or acting like the body’s immune system response against cancer cells. Different types of biological therapies work in different ways.
Biological therapy is based on the theory that the immune system helps destroy cancer cells.
A number of different biological therapies are used to treat certain types of cancer. Biological therapies can be confusing because they aren’t grouped in a simple, easy-to-follow way. Some biological drugs are grouped according to the effect they have, such as blocking cell growth. Others are grouped by a particular type of drug, and some drugs belong to more than one group.
Immunotherapy is a type of biological therapy that uses the immune system to help destroy cancer cells. Immunotherapy may be active or passive.
Cytokines are naturally occurring chemicals made by different immune system cells. They are the messengers of the immune system. Cytokines allow immune system cells to communicate with each other and thus help carry out the immune system response.
Monoclonal antibodies are made in the laboratory. They find and bind to a specific antigen on a cancer cell. Monoclonal antibodies may:
Cancer vaccines work just like vaccines for other diseases, such as measles or chicken pox. They are injected after cancer is diagnosed. Vaccines may encourage the person’s immune system to identify cancer cells and stimulate T cells to attack them. For example, bacillus Calmette-Guérin (BCG) vaccine is used to treat bladder cancer. Cancer vaccines may also help prevent cancer from recurring (coming back).
Angiogenesis is the growth of new blood vessels. A tumour has to make new blood vessels to grow, but normal organs do not. Anti-angiogenesis drugs try to starve the tumour by stopping the development of new blood vessels.
Colony-stimulating factors (CSFs) do not directly affect tumour cells. They stimulate the bone marrow to produce more red blood cells, white blood cells and platelets. CSFs are used to treat side effects of cancer treatments that may make someone more vulnerable to anemia, infection or bleeding.
Growth factors are naturally occurring chemicals that control cell growth. Cancer growth inhibitors block the growth factors that make cancer cells divide and grow. The different types of cancer growth inhibitors are named after the type of chemical they block. The main types are:
Researchers are actively studying gene therapygene therapyTreatment that changes a gene. Genes responsible for disease are corrected or a malfunctioning gene is replaced with a normal one to help the body fight a variety of diseases, including cancer. as a cancer treatment. This therapy introduces genetic material into a person’s cells to repair a mutation. Researchers are looking at ways of using gene therapy to change a person with cancer’s genetic material to fight or prevent disease.
For more detailed information on specific drugs, go to sources of drug information.
The type of biological therapy used depends on the type and stage of cancer. Each type works differently to stimulate or strengthen the immune system. Biological therapy may be used alone or it may be combined with other cancer treatments, such as surgery, chemotherapy or radiation therapy.
Getting biological therapy includes assessment before treatment, having the treatment and follow-up after treatment is finished.
When children are diagnosed with cancer, both children and their families have questions and concerns about biological therapy. They want to know how it is given and how to manage the treatment. Being prepared and knowing what to expect can reduce anxiety for both children and parents. Parents and caregivers can prepare and help children cope with biological therapy by giving them explanations that are appropriate to their age and maturity.
Biological therapy travels through the entire body, so side effects affect the whole body as well. How bad side effects are depends on the type of biological therapy, the dose of the drug, how the drug is given and the schedule for taking the drug. Most side effects of biological therapy can be treated with other drugs. Side effects will improve once biological therapy is finished.