Chronic myelogenous leukemia (CML) is a cancer of the blood in which too many granulocytes, a type of white blood cell, build up in the bone marrow. CML is also called chronic myeloid leukemia.
Normally, bone marrow cells mature into several different types of blood cells. CML affects the young blood cells called blasts that normally develop into a type of white blood cell called granulocytes. The main function of granulocytes is to destroy bacteria. The blasts do not mature, increase to large numbers, and remain in the bone marrow and blood.
Chronic myelogenous leukemia can occur over a period of months or years. A specific chromosome rearrangement is found in the cells of almost all patients with CML. Parts of chromosome #9 and chromosome #22 switch places, so that there is an exchange of genetic material between these 2 chromosomes. This rearrangement changes the position and functions of certain genes, which results in uncontrolled cell growth. The shortened chromosome #22 is often called the Philadelphia chromosome. Nearly all patients with CML have the Philadelphia chromosome in their cells. Other chromosome abnormalities can also be present.
CML occurs mainly in adults and is rare in children. According to the American Cancer Society, about 5,900 cases of CML are expected in the United States in 2013.
Many people do not have symptoms in the early phase of CML. Instead, the leukemia is found during routine blood tests. When people do have symptoms from CML, the following are the most common. However, each individual may experience symptoms differently. Symptoms may include:
Aches in bones and joints
The symptoms of chronic myelogenous leukemia may resemble other blood disorders or medical problems. Always consult your doctor for a diagnosis.
In addition to a complete medical history and physical examination, diagnostic procedures for chronic myelogenous leukemia may include:
Blood tests and other evaluation procedures
Bone marrow aspiration and/or biopsy. A procedure that involves taking a small amount of bone marrow fluid (aspiration) and/or solid bone marrow tissue (called a core biopsy), usually from the hip bones, to be examined for the number, size, and maturity of blood cells and/or abnormal cells.
Specific treatment for chronic myelogenous leukemia will be determined by your doctor based on:
Your age, overall health, and medical history
Extent of the disease
Your tolerance for specific medications, procedures, or therapies
Expectations for the course of the disease
Your opinion or preference
Treatment may include:
Targeted therapies, such as imatinib, dasatinib, or nilotinib
Biological therapy. This therapy uses the body's immune system to fight cancer.
Stem cell transplantation
Splenectomy. Surgery to remove the spleen.