Types of Leukemia

Leukemia is not staged numerically (I, II, III, IV) the way many other cancers are staged. Rather, it is classified as acute or chronic. Acute leukemia grows more rapidly than chronic leukemia. Acute leukemia is a potentially life-threatening condition and requires urgent and intensive treatments. Chronic leukemia has a slower onset and is not usually life threatening at the time of diagnosis. Leukemia is also classified by the type of white blood cells in which it arises, lymphoid cells or myeloid cells.

  • Acute lymphocytic leukemia is a cancer that begins in the white blood cells called lymphocytes. This process occurs in the bone marrow (the soft inner part of the bones, where new blood cells are made). These affected immune cells can consist of either T cells or B cells.

    ALL is most commonly found in children, but it also occurs in adults.

    Treatment Approach:

    Chemotherapy (treatment with anticancer drugs) is the primary treatment for ALL. There are several phases of treatment:

    Induction: This phase of chemotherapy is administered in the hospital and lasts for approximately three weeks. This typically requires you to stay inpatient until your counts recover. A bone marrow biopsy test is performed at the end of the induction treatment to see if the leukemia is in remission (meaning the bone marrow biopsy shows no evidence of leukemia).

    Consolidation: Even if bone marrow tests do not show leukemia cells (indicating you are in remission), it is possible that some cells have still survived. At this point, consolidation chemotherapy is given to destroy any remaining leukemia cells that may have survived induction. You may be able to receive consolidation in an outpatient setting. Depending on the drug combination chosen for your treatment, you may need to be periodically readmitted to the hospital for some parts of your consolidation.

    Central Nervous System (CNS): ALL sometimes appears in the brain and spinal cord. We try to prevent this by giving chemotherapy directly into the spinal fluid. Occasionally, radiation therapy (targeted X-rays to destroy tumors) to the brain is also necessary.

    Maintenance/Intensification: This phase of chemotherapeutic treatment lasts for up to 2 1/2 years from the completion of consolidation. Maintenance involves taking oral medications at home and having intermittent, intravenous chemotherapy. During maintenance treatment, you may be able to return to work and take part in some normal daily activities. Your physician will discuss any precautions you must take or any limitations in activities. You may receive intensification cycles during your maintenance. These stronger doses of IV chemotherapy will require you to limit your activities again during these cycles. You will have regular blood and bone marrow testing performed during your maintenance treatment and for some time afterwards to evaluate your disease status.

    Bone Marrow/Stem Cell Transplantation (BMT): After completing induction and/or consolidation chemotherapy, your physician may recommend you undergo a bone marrow or stem cell transplant in order to give you the best chance of curing your leukemia. BMT Process

  • Acute myelogenous leukemia is the most common type of acute leukemia in adults. It occurs in myeloid cells, which are a class of blood cells that normally develop into red and white blood cells and platelets.

    Treatment Approach:

    Chemotherapy (treatment with anticancer drugs) is the primary treatment for AML. There are multiple phases of treatment:

    Induction: This phase of chemotherapy is administered in the hospital and lasts for approximately four to six weeks. This will typically require you to stay inpatient until your counts recover. A bone marrow biopsy test is performed at the end of the induction treatment to see if the leukemia is in remission (meaning the bone marrow biopsy shows no evidence of leukemia).

    Consolidation Therapy: Even if bone marrow tests do not show leukemia cells (indicating you are in remission), it is possible that some cells have still survived. At this point, additional consolidation chemotherapy is given to destroy any remaining leukemia cells that may have survived induction. You may be able to receive consolidation in an outpatient setting.

    Bone Marrow/Stem Cell Transplantation (BMT): After completing induction and/or consolidation chemotherapy treatment, your physician may recommend you undergo a bone marrow or stem cell transplant in order to give you the best chance of curing your leukemia. BMT Process

  • Acute promyelocytic leukemia is a FAB subtype (M3) of AML that differs from the other types of AML. APL is associated with a high risk of bleeding. It has been shown to respond well to a specific drug, all-trans-retinoic acid (ATRA), in combination with arsenic trioxide, or sometimes in combination with standard chemotherapy.

    Treatment Approach:

    Chemotherapy is the main treatment for APL and has multiple phases:

    Induction: Patients with APL are commonly treated with all-trans-retinoic acid (ATRA) and arsenic trioxide therapy, sometimes in combination with other chemotherapy medications. Due to the high risk of bleeding and potential for serious side effects, you will remain in the hospital for careful monitoring during induction. After an appropriate amount of treatment, a bone marrow biopsy will be done to determine if the leukemia is in remission.

    Consolidation: Even if bone marrow tests do not show leukemia cells (indicating you are in remission), it is possible that some cells have still survived. At this point, additional consolidation chemotherapy is given to destroy any remaining leukemia cells that may have survived induction. Consolidation most commonly consists of ATRA and arsenic trioxide, with or without additional chemotherapy. You will generally receive this treatment in an outpatient setting.

    Maintenance: Some patients will receive maintenance treatment. This consists of taking oral medications for a 2-year period. Blood tests and bone marrow biopsies will be performed regularly to evaluate your disease status.

  • CLL is a type of leukemia that leads to the overproduction of certain white blood cells. It generally occurs in older adults and progresses slowly, although the disease can become more aggressive over time.

    Treatment Approach:

    Treatment in the early stages may include observation. Chemotherapy is usually given when symptoms occur, and most patients will respond well to therapy. Eventually, CLL will not respond well to chemotherapy, and bone marrow or stem cell transplantation may be recommended.

  • CML is a slow-growing leukemia that leads to your bone marrow producing a large amount of white blood cells.

    It is common for CML patients to have a genetic mutation known as the “Philadelphia Chromosome.”

    The “Philadelphia Chromosome” is formed when DNA (genetic instructions) from chromosome 9 gets translocated or “misplaced” onto chromosome 22.

    This change causes the overproduction of an enzyme called tyrosine kinase, which tells the bone marrow to make too many white blood cells.

    Specific drugs (e.g., Gleevec (Imatinib) or Sprycel (Dasatinib)) were developed to block this enzyme and have become a standard therapy for the disease.

    CML is also 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, however, patients progress from the chronic phase to an accelerated phase and then to an acute leukemia phase, during which time the leukemia cells grow more quickly.

    Treatment Approach:

    The chronic phase can be controlled with a BCR-ABL tyrosine kinase inhibitor (TKI) like Gleevec. If you do not respond to Gleevec, you may respond to Sprycel. Other tyrosine kinase agents are available for those patients who do not respond to Gleevec or Sprycel.

    If you do not respond to a TKI, your physician may recommend that you undergo a bone marrow or stem cell transplant in order to give you the best chance of curing your leukemia. BMT Process

  • Myelodysplastic Syndromes (MDS) are now thought to be the most common blood and bone marrow disorders. While estimates vary, as many as 20,000 to 30,000 people in the U.S. may be diagnosed annually with MDS. The disorders can lead to low blood counts, infections, bleeding, the need for transfusions, and life-threatening bone-marrow failure. As the disease progresses, it can evolve into an aggressive type of acute myelogenous leukemia (AML).

    Treatment Approach:

    Myelodysplastic Syndromes are now thought to be the most common blood and bone marrow disorders. While estimates vary, as many as 20,000 to 30,000 people in the U.S. may be diagnosed annually with MDS. The disorders can lead to low blood counts, infections, bleeding, the need for transfusions, and life-threatening bone marrow failure. As the disease progresses, it can evolve into an aggressive type of acute myelogenous leukemia (AML).

    Treatment Approach:

    MDS treatments focus on improving blood counts, quality of life and preventing or delaying progression to more severe forms of acute leukemia. This is particularly important because the more aggressive forms of acute leukemia associated with MDS do not respond well to chemotherapy.

    Low-intensity chemotherapy medications (e.g., Vidaza, Dacogen, Revlimid) are sometimes given to slow down the growth of MDS and delay progression to AML. However, bone marrow or stem cell transplantation remains the only curative treatment for this disease and may be recommended.
    BMT Process