Johns Hopkins is home to one of the largest leukemia programs worldwide. Groundbreaking treatments in all types of leukemias and blood disorders are just the beginning of unparalleled care and commitment to our patients and families in the Johns Hopkins Leukemia Program.
About Chronic Myelogenous Leukemia (CML)
A slow growing leukemia, chronic myelogenous leukemia (CML) is characterized by an overgrowth of white blood cells. It occurs mainly in adults. Scientists have long known that in CML patients, chromosomes 9 and 12 fuse together to form the “Philadelphia” chromosome. The Philadelphia chromosome overproduces an enzyme called tyrosine kinase causing the bone marrow to make too many white blood cells. A drug called Gleevec was developed to block this enzyme and has become a standard therapy for the disease.
CML is usually diagnosed with bone marrow aspiration, which involves taking a sample of cells or tissues from the bone marrow to examine under the microscope for abnormalities. The diagnosis is usually confirmed by finding the Philadelphia chromosome in the cells. In some cases, special molecular tests are required to detect an abnormal gene known as bcr/abl, when the Philadelphia chromosome is not detected by usual methods.
In May 2001, the Food and Drug Administration (FDA) approved the new drug Gleevec (also know as Glivec or STI-571) for use in patients with chronic myelogenous leukemia. This drug is considered to represent a new direction in the treatment of cancer by its ability to target only the myeloid cells and leave healthy cells unharmed. A number of centers, including the Johns Hopkins Kimmel Cancer Center, were involved in the initial studies of this drug and researchers are continuing to investigate its benefit through clinical trials.
New Treatment Approaches
For patients whose cancer returns after Gleevec therapy, Johns Hopkins investigators are studying ways to use the body’s immune system to attack the cancer using a vaccine to prime immune cells to recognize and destroy cancerous ones. Other agents that target the biologic nature of CML also are being studied.
New generations of experimental tyrosine kinase inhibitors, including the drugs nilotinib and dasatinib, also are being studied.