The immune system is a complex network of cells and organs located throughout the body. Its job is to fight infection caused by bacteria, viruses and fungi. White blood cells, for example, are a critical part of the immune system. Many directly attack “invaders.” These invaders can be anything from bacteria to cancer cells. Other types of cells produce substances such as antibodies that work in similar ways to protect you from disease.

Thanks to ongoing cancer research, many of the substances found naturally in the immune system can now be reproduced in the laboratory and used as part of cancer treatment. This is called biological therapy or “immunotherapy.”

Biologic Substances

These laboratory-produced substances work in many ways. “Interleukins,” for example, stimulate the growth and activity of many immune cells, while “interferons” can improve the way the immune system as a whole responds to cancer cells. Other types of substances, called “colony-stimulating factors,” encourage bone-marrow stem cells to divide and develop into white blood cells, platelets and red blood cells. This is particularly helpful for certain types of cancer patients whose blood-cell counts are greatly reduced during high-dose chemotherapy treatments.

Medical oncologists are physicians who specialize in treating cancer with a variety of cancer-fighting medications. Our medical oncologists meet with patients and their families to determine an individualized treatment plan working with other cancer specialists and oncology nurses.

If biological therapy is part of your treatment plan, your medical oncologist will prescribe a series of treatments, usually administered by injections of the biologic substances.


If your doctor believes you are a good candidate to participate in a clinical trial evaluating  a new treatment or more effective combinations of treatments — and you agree — you will have access to the very latest in research treatments.

Learn more about Clinical Trials

Monocolonal Antibody Therapy

Monoclonal antibody therapy is one of the newer forms of biological therapy. Monoclonal antibodies are laboratory-produced substances that can locate and bind with certain types of cancer cells in the body. They affect these cells in different ways. Some "mark" the cancer cells so the immune system can destroy them. Others attach to special sites on the cell, where growth-stimulating molecules might otherwise attach. By blocking the other molecules from attaching there, the monoclonal antibodies prevent the cancer cells from growing rapidly.

Side Effects

Like other forms of cancer treatment, biological therapies can cause a number of side effects, which can vary widely from patient to patient. Rashes or swelling may develop in the place where the injection is given. Many cause flu-like symptoms including fever, chills, nausea, vomiting and appetite loss. Fatigue is another common side effect, and blood pressure may also be affected. The side effects of some types of biological therapy can be severe. Patients who receive these types are closely monitored during treatment.

Appointments & Referrals

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If you need a help to find a medical oncologist and/or a location, please call at 1-(855)-XCANCER (1-855-9226237) or (206) 215-3600.