Chronic myelogenous leukemia is a malignant cancer of the bone marrow that causes rapid growth of the blood forming cells (known as myeloid precursors) in the bone marrow, peripheral blood, and body tissues.

Alternative Names

Chronic granulocytic leukemia

Causes, incidence, and risk factors

The disease occurs in middle-aged people and children and is associated with a chromosome abnormality called the Philadelphia chromosome . Chronic myelogenous leukemia is characterized by a chronic phase that can last for months or years. The disease may have few or no symptoms during the chronic phase. Eventually, patients progress from the chronic phase to a more dangerous "accerated phase," during which the leukemia cells grow more quickly. Acceleration of the disease may be associated with fever (without infection), bone pain and an enlarged spleen . Within 5 years, in most people, the disease then progresses to a "blast crisis," when there is a very high count of immature white blood cells (leukemia cells). The blast phase of the leukemia is very difficult to treat. Bleeding and infection may occur due to bone marrow failure. Known risk factors to develop CML are exposure to ionizing radiation and benzene.

Signs and tests

A

physical examination often reveals an enlarged spleen .

A

CBC shows increased white blood cell count .

A CBC

differential is consistent with increased numbers of white blood cells, either mature or immature (depending on whether the disease is in the chronic or blast phase). Additional signs and tests include:

Bone marrow aspiration

The presence of the

Philadelphia chromosome

The

leukocyte alkaline phosphatase level This disease may also alter the results of the following tests:

Vitamin B-12 level

Uric acid

Platelet count

Treatment

Treatment is aimed at reducing the growth of the leukemic cells in the bone marrow and may bring about a remission (when no leukemia can be found) with good control of the symptoms of the disease.

The chronic phase can be controlled with chemotherapy , which can be given as an outpatient. Interferon has been used to achieve temporary remission. The FDA recently approved a new drug for CML called imatineb (Gleevec), which is particularly effective when the disease has not responded to standard treatment (bone marrow transplant). This drug works directly on the leukemic cells to slow their growth. A bone marrow transplant preceded by high-dose chemotherapy and radiation therapy remains the standard treatment, however, although not all people with CML are suitable candidates for transplantation or have a suitable donor. It is not known at the present time which patients should receive a bone marrow transplant as the first treatment and who should receive Gleevec. Participation in a medical study ("clinical trial") comparing these treatments may be appropriate. Since treatment recommedations for CML are changing quickly with new research findings, you should discuss in detail with your oncologist the advantages and disadvantages of each option. SELF CARE MEASURES To minimize bleeding , apply ice and pressure to any external bleeding. A soft toothbrush and electric razor should be used for personal hygiene. An increase in calories and protein in diet may help reduce the side effects associated with chemotherapy. Planning daily activities with scheduled rest periods can help to prevent the fatigue associated with anemia .

Support groups

The stress of illness can often be helped by joining a support group where members share common experiences and problems. For this condition, see cancer - support group and leukemia - support group .

Expectations (prognosis)

Without curative treatment, the disease is always fatal. On average, the survival is 3 to 4 years. Over half of those who receive a bone marrow transplant have long-term disease-free survival. The long-term survival after Gleevec alone is not known.

Complications

Blast crisis can lead to complications of CML, including infection, bleeding, fatigue, unexplained fever, and kidney problems. Chemotherapy can have serious side effects, depending on the drugs used.

Calling your health care provider

Call your health care provider if you have symptoms suggestive of CML or have been diagnosed with CML and develop a fever higher than 100 degrees Fahrenheit, chills, sore throat, or cough.

Prevention

Avoid radiation and benzene if possible.