Types of Leukemia and Their Treatment
Leukemias are grouped by how quickly the disease develops and progresses:
- Acute leukemia – gets worse quickly as the production of abnormal cells increases rapidly.
- Chronic leukemia – gets worse slowly and symptoms may not appear for a long time.
Blood cells are produced inside the bone in a spongy space called the bone marrow.
Blood Stem Cell
All blood cells have a common origin called a stem cell. Two “lines” of cells develop from stem cells: lymphoid cells, which give rise to white blood cells called lymphocytes, and myeloid cells, which give rise to red blood cells, other white blood cells, and platelets. Early immature cells are called blasts, which grow into mature red or white blood cells and platelets, as shown on the lower left.
Myeloid stem cell
When myeloid cells are affected, the disease is called myeloid or myelogenous leukemia.
Acute Myeloid Leukemia (AML)
AML occurs more commonly in adults than in children. Treatment: Includes chemotherapy or targeted therapy.
- Chemotherapy is given in several phases:
- Induction phase – 2 to 3 different chemotherapy drugs are given; the goal is to achieve remission (no detectable cancer can be found)
- Post-remission therapy – multiple drugs are used to destroy any remaining cancer cells
- Consolidation therapy – involves additional chemotherapy or SCT
- Targeted therapy is given to patients in whom the cancer has come back or whose AML is caused by a specific genetic change called FLT3.
Chronic Myeloid Leukemia (CML)
CML occurs mainly in adults. Most people with CML are found to have an abnormal chromosome known as the Philadelphia chromosome. This chromosome causes the cell to make a protein that stimulates the leukemic cells to grow and multiply.
SCT is used if initial treatment fails or in accelerated phases of the disease.
When leukemia affects lymphoid cells, it is called lymphocytic leukemia
Acute Lymphoblastic Leukemia (ALL)
ALL is the most common type of leukemia in young children. This disease also affects adults, especially those age 65 and older. Treatment: Includes chemotherapy and/or SCT.
- Chemotherapy is given in four phases to treat ALL:
- Induction phase – anticancer drugs are used to destroy cancer cells to achieve remission (tests show no detectable cancer in the body
- Central nervous system directed therapy – anticancer drugs are directed at the leukemic cells in the brain and spinal cord
- Consolidation phase – higher doses or new combinations of drugs are used to destroy any leukemia cells that are still “hiding” within the body
- Maintenance phase – drugs are used to keep the cancer in remission (treatment can last 2 to 3 years)
- SCT is most often used for ALL that has come back after chemotherapy treatment or in patients for whom chemotherapy has not worked.
Chronic Lymphocytic Leukemia (CLL)
CLL most often affects adults older than age 55. It sometimes occurs in younger adults, but it rarely affects children. Treatment: Several options are available depending on stage and severity of symptoms.
- “Active surveillance,” in which regular examinations and blood counts are done to monitor the cancer, is recommended for patients with early-stage disease and no symptoms.
- Chemotherapy with a single drug or combination of drugs.
- Targeted therapy:
- Monoclonal antibodies are drugs created in the lab to specifically react with certain types of cancer cells. They help the patient’s immune system destroy cancer cells.
- Kinase inhibitors target a protein that allows cancer cells to grow and divide.