The leukemia has been treated but no longer responds to the treatment. Some people with hairy cell leukemia have few symptoms and may not need treatment right away. There are treatments for all patients with hairy cell leukemia that is causing symptoms. Bone marrow transplants are being tested in clinical trials. If the spleen is swollen, the doctor may take out the spleen in an operation called a splenectomy.
Chemotherapy uses drugs to kill cancer cells.
Chemotherapy may be taken by pill, or it may be put into the body by a needle in the vein, muscle, or under the skin. Chemotherapy is called a systemic treatment because the drug enters the bloodstream, travels through the body, and can kill cancer cells throughout the body. Biological therapy tries to get the body to fight the cancer. It uses materials made by the body or made in a laboratory to boost, direct, or restore the body's natural defenses against disease. Interferon, a substance made by the body to fight off foreign materials, is often used to treat hairy cell leukemia.