Immunotherapy is also called biologic therapy or biotherapy. It is treatment that uses certain parts of the immune system to fight disease, including cancer. This can be done in a couple of ways:
- stimulating your own immune system to work harder or smarter
- giving you immune system components, such as man-made immune system proteins
Immunotherapy is sometimes used by itself to treat cancer, but it is most often used along with or after another type of treatment to boost its effects.
For a long time doctors suspected that the immune system had an effect on certain cancers. Even before the immune system was well understood, William Coley, MD, a New York surgeon, first noted that getting an infection after surgery seemed to help some cancer patients. In the late 1800s, he began treating cancer patients by infecting them with certain kinds of bacteria, which came to be known as Coley toxins. Although he had some success, his technique was overshadowed when other forms of cancer treatment, such as radiation therapy, came into use.
Doctors have learned a great deal about the immune system since that time. This has led to research into how it can be used to combat cancer, with many different approaches being explored. In the last few decades immunotherapy has proven useful in treating several types of cancer.
The idea of using one's own immune system to fight cancer is tempting, but immunotherapy still has a fairly small role in treating most cancers. So far, in most cases, it hasn't been shown to clearly be better than other forms of treatment. For instance, it seems most likely to be effective when treating smaller, early stage cancers, and it may be less helpful for more advanced disease. Its main role at this time is making other forms of treatment better or providing cancer patients with another, often less toxic, treatment option.
But researchers have made important progress in this field in recent years. Newer, more effective treatments are now being tested that will have a greater impact on the outlook for people with cancer in the future.