Leukemias are cancers of stem cells that should develop into healthy blood cells. All leukemias are characterized by the proliferation of abnormal or underdeveloped blood cells.

Acute leukemias are distinguished by the rapid over-production of very immature, undifferentiated blast cells in the bone marrow. Normal marrow becomes over-crowded by these non-functioning cells and unable to produce healthy blood cells. Because the progression of acute leukemias is very quick, immediate treatment is necessary.

Chronic leukemias are also characterized by the excessive build up of abnormal cells, but these cells are usually more developed and mature than those found in acute forms. The proliferation of these cells proceeds far more slowly than in acute cases, so physicians often monitor the progress of the disease over time, sometimes delaying treatment to ensure the best possible outcome for the patient.

Acute Myelogenous Leukemia (AML)

In Acute Myelogenous (or Myeloid) Leukemia, the bone marrow produces too many blast cells. Blast cells are precursor cells which normally develop into white blood cells that fight infection. In AML, however, the blasts do not mature and therefore cannot fight infection. These abnormal cells reproduce very quickly, often displacing normal blood cells. They can crowd out other healthy cells, affecting red blood cell and platelet formation.

Symptoms may include anemia, fatigue and possibly fever due to infection. If platelet production has been severely impacted, easy bruising and/or bleeding may occur.

Chronic Myelogenous Leukemia (CML)

Chronic Myelogenous (or Myeloid) Leukemia is a slow-growing cancer, which causes too many granulocytes (a type of white blood cell) to be produced. These cells build up in the bone marrow and crowd out healthy white blood cells, red blood cells, and platelets.

In general, patients with CML do not experience any noticeable symptoms. A diagnosis may be suspected due to an elevated white blood cell count visible in a routine laboratory test. If symptoms do occur, they can include: fever, weight loss, anemia, infections and/or enlarged spleen.

Acute Lymphocytic Leukemia (ALL)

In Acute Lymphocytic (or Lymphoid) Leukemia, immature white blood cells are overproduced in the bone marrow, and cause damage and death by crowding out normal cells in the bone marrow and by spreading to other organs.

Symptoms can include weakness, fatigue, anemia, fever, infections, weight loss, bone pain, shortness of breath, and/or enlarged lymph nodes, liver, or spleen.

Chronic Lymphocytic Leukemia (CLL)

Chronic Lymphocytic Leukemia affects B-lymphocytes. These cells originate in the bone marrow, develop to maturity in the lymph system and normally fight infection. In CLL, the DNA of these types of lymphocytes is damaged and they grow out of control, crowding out normal cells.