Chronic myelogenous leukemia is a common form of leukemia and in most cases appears in adults; and about 2—4% of cases are children. Most patients with chronic myelogenous leukemia (95%) have a chromosomal abnormality called Philadelphia chromosome—a gene mutation that results in the bone marrow creating an enzyme called tyrosine kinase that causes too many stem cells to develop into white blood cells (granulocytes or blast).

Chronic myelogenous leukemia has 3 classification phases—chronic, accelerated, and blastic—based on the number of blast cells in the blood and bone marrow and by the severity of symptoms.

In chronic phase chronic myelogenous leukemia, fewer than 10% of the cells in the blood and bone marrow are blast cells, and usually last two to five years or more before turning into the accelerated phase. In accelerated phase CML anywhere from 10—19% of cells in the blood and bone marrow are blast cells. In blastic phase CML 20% or more of the cells in the blood or bone marrow are blast cells.

There are different types of treatment for patients with chronic myelogenous leukemia. Some treatments are standard and some are in clinical trials—conducted trails to allow safety and efficacy date to be collected for new leukemia drugs. There are six different types of standard treatments:

· The initial treatment for certain types of chronic myelogenous leukemia in newly diagnosed patients is a drug called imatinib mesylate. It blocks an enzyme called tyrosine kinase that causes more stem cells to develop into white blood cells (granulocytes or blast) than necessary. Another tyroxine kinase inhibator—dasatinib is also used to treat certain types of chronic myelogenous leukemia.

• Chemotherapy is another drug treatment to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing.
• Biological therapy is a treatment that uses the patient’s immune system to fight cancer.
• High dose chemotherapy with stem cell transplant is a treatment of giving high doses of chemotherapy and replacing blood-forming cells destroyed by the chemotherapy—either autologous or allogeneic stem cell transplantation.
• Donor lymphocyte infusion is a post stem cell cancer treatment where lymphocytes from the stem cells are removed from the patient and stored for future infusions following stem cell treatments.
• Surgery where the spleen (splenectomy) is removed.

Chronic Phase Chronic Myelogenous Leukemia treatments may consist of:

• Drug therapy with a tyrosine kinase inhibitor—Imatinib, dasatinib (Sprycel^®) and nilotinib (Tasigna^®)
• Splenectomy
• Biological therapy with or without chemotherapy
• High-dose chemotherapy with donor stem cell transplant
• A clinical trial drug with or without donor stem cell transplant

Accelerated Phase Chronic Mylogenous Leukemia treatments may include:

• Stem cell transplantation
• Drug therapy with a tyrosine kinase inhibitor—Imatinib, dasatinib (Sprycel^®) and nilotinib (Tasigna^®)
• High-dose chemotherapy with donor stem cell transplant
• Transfusion therapy

Treatments for Blastic Phase Chronic Myelogenous Leukemia include:

• Drug therapy with a tyrosine kinase inhibitor
• Chemotherapy using one or more drugs
• High-dose chemotherapy with donor stem cell transplant
• Pallative therapy