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Leukemia

Topic Overview

What is leukemia?

Leukemia is cancer of the blood cells. It starts in the bone marrow, the soft tissue inside most bones. Bone marrow is where blood cells are made.

When you have leukemia, the bone marrow starts to make a lot of abnormal white blood cells, called leukemia cells. They don't do the work of normal white blood cells. They grow faster than normal cells, and they don't stop growing when they should.

Over time, leukemia cells can crowd out the normal blood cells. This can lead to serious problems such as anemia, bleeding, and infections. Leukemia cells can also spread to the lymph nodes or other organs and cause swelling or pain.

Are there different types of leukemia?

There are several different types of leukemia. In general, leukemia is grouped by how fast it gets worse and what kind of white blood cell it affects.

  • It may be acute or chronic. Acute leukemia gets worse very fast and may make you feel sick right away. Chronic leukemia gets worse slowly and may not cause symptoms for years.
  • It may be lymphocytic or myelogenous. Lymphocytic (or lymphoblastic) leukemia affects white blood cells called lymphocytes. Myelogenous leukemia affects the other type of cells that normally become granulocytes, red blood cells, or platelets.

The four main types of leukemia are:

There are less common leukemias, such as hairy cell leukemia. There are also subtypes of leukemia, such as acute promyelocytic leukemia (a subtype of AML).

What causes leukemia?

Experts don't know what causes leukemia. Some things may increase your risk, such as being exposed to large amounts of radiation and being exposed to certain chemicals at work, such as benzene.

What are the symptoms?

Symptoms may depend on what type of leukemia you have, but common symptoms include:

  • A new lump or swollen gland in your neck, under your arm, or in your groin.
  • Frequent nosebleeds, bleeding from the gums or rectum, more frequent bruising, or very heavy menstrual bleeding.
  • Frequent fevers.
  • Night sweats.
  • Bone pain.
  • Unexplained appetite loss or recent weight loss.
  • Feeling tired a lot without a known reason.
  • Swelling and pain on the left side of the belly.

How is leukemia diagnosed?

To find out if you have leukemia, a doctor will:

  • Ask questions about your past health and symptoms.
  • Do a physical exam. The doctor will look for swollen lymph nodes and check to see if your spleen or liver is enlarged.
  • Order blood tests. Leukemia causes a high level of white blood cells and low levels of other types of blood cells.

If your blood tests aren't normal, the doctor may want to do a bone marrow biopsy. This test lets the doctor look at cells from inside your bone. This can give key information about what type of leukemia it is so you can get the right treatment.

How is it treated?

What type of treatment you need will depend on many things, including what kind of leukemia you have, how far along it is, and your age and overall health.

  • If you have acute leukemia, you will need quick treatment to stop the rapid growth of leukemia cells.
  • Chronic lymphocytic leukemia may not need to be treated until you have symptoms. But chronic myelogenous leukemia will probably be treated right away.

Treatments for leukemia include:

  • Chemotherapy. This is the main treatment for most types of leukemia.
  • Radiation.
  • Stem cell transplant. Stem cells can rebuild your supply of normal blood cells and boost your immune system.
  • Targeted therapy. This is the use of special medicines that stop cancer cells from multiplying.

Cause

Experts don't know what causes leukemia. But some things can increase the risk of some kinds of leukemia. To learn more, see What Increases Your Risk.

Symptoms

Symptoms of acute leukemia depend on how much the cancer has grown. They may include:

  • A new lump or swollen gland in your neck, under your arm, or in your groin.
  • Frequent nosebleeds, bleeding from the gums or rectum, more frequent bruising, or very heavy menstrual bleeding.
  • Frequent fevers.
  • Night sweats.
  • Bone pain.
  • Unexplained appetite loss or recent weight loss.
  • Feeling tired a lot without a known reason.
  • Swelling and pain on the left side of the belly.

The chronic forms of leukemia often cause no symptoms until much later in the disease. And when symptoms appear, they usually appear gradually.

What Happens

Your bone marrow is where stem cells grow. These stem cells become white blood cells, red blood cells, and platelets.

In most cases of leukemia, there are too many abnormal white blood cells. These leukemia cells crowd out the normal blood cells in your bone marrow and build up in your lymph nodes, liver, and spleen.

When the leukemia cells crowd out your normal cells, your blood can't do its job. You may bleed or bruise easily, have more infections, and feel very tired.

Remission

Leukemia can go away. People sometimes call this a "cure." But your doctor may use the term "remission" instead of "cure" when talking about the effectiveness of your treatment. Many people who have leukemia are successfully treated, but the term remission is used because cancer can return (recur). It is important to discuss the possibility of recurrence with your doctor.

What Increases Your Risk

Some things can increase your chances of getting leukemia. These things are called risk factors. But many people who get leukemia don't have any of these risk factors. And some people who have risk factors don't get this cancer.

General risk factors for leukemia

Other risk factors for AML

  • Exposure to chemicals, such as benzene and formaldehyde.

Other risk factors for CLL

  • Your family history. In some cases, CLL runs in families.
  • Being middle-aged or older, male, and white.
  • Being infected with a virus known as HTLV-1.

Other risk factors for CML

  • Having a gene change (mutation) called the Philadelphia chromosome.

When should you call your doctor?

Call your doctor to schedule an appointment if you have any symptoms, such as:

  • A new lump or swollen gland in your neck, under your arm, or in your groin.
  • Frequent nosebleeds, bleeding from the gums or rectum, more frequent bruising, or very heavy menstrual bleeding.
  • Frequent fevers.
  • Night sweats.
  • Bone pain.
  • Unexplained appetite loss or recent weight loss.
  • Feeling tired a lot without a known reason.
  • Swelling and pain on the left side of the belly.

If you have been diagnosed with cancer, be sure to follow your doctor's instructions about calling when you have problems, new symptoms, or symptoms that get worse.

Watchful waiting

Watchful waiting is a wait-and-see approach. It may be a treatment choice, depending on the stage of the leukemia and your overall health.

Doctors may use watchful waiting for patients with chronic lymphocytic leukemia (CLL) at first, because treatment may not be needed. People who have CLL often live for a long time without treatment.

Watchful waiting isn't usually recommended for other types of leukemia.

Exams and Tests

Tests to diagnose leukemia

If your doctor suspects leukemia, he or she may:

  • Ask about your medical history.
  • Check for enlarged lymph nodes in your neck, underarm, or groin.
  • Check for an enlarged liver or spleen.
  • Do a complete blood count (CBC) and a blood chemistry. These tests let your doctor look into symptoms such as fatigue, weakness, fever, bruising, or weight loss.
  • Do a bone marrow aspiration and biopsy. This is the key to diagnosing most leukemias and helps determine the type.

Finding the type of leukemia

If your blood work points to possible leukemia, your doctor will want to find out what kind you might have. Your treatment plan will depend on the specific kind of leukemia that you have.

  • A blood test is usually enough to find signs of chronic lymphocytic leukemia (CLL).
  • Tests that look closely at unusual cells, chromosomes, or proteins on cells can show what type or subtype of leukemia you have. These tests include:
    • A test that looks for certain changes in the cell chromosomes from a sample of blood or bone marrow (cytogenetic analysis).
    • A test that compares cancer cells to normal blood cells to find the specific kind of leukemia (immunophenotyping).
    • A test to look for genes that are "turned on" in several types of leukemia, such as acute myelogenous leukemia (AML). This test is called a reverse transcription-polymerase chain reaction test, or RT-PCR.

These tests can help guide treatment. Sometimes they can help your doctor and you know whether your leukemia is likely to go into remission or come back. In some cases, the tests can predict survival rates.

Your doctor may also order other tests, including:

  • Chest X-rays, to find out if leukemia or an infection is the cause of lung problems such as persistent coughing, coughing up blood, chest pain, or trouble breathing.
  • CT scan of the head, chest, and belly, to find out if leukemia has spread there.
  • Lumbar puncture, to find out if leukemia cells are in your cerebrospinal fluid (CSF).
  • MRI of the brain, to look into symptoms such as confusion, paralysis, numbness, vision problems, vertigo, or headaches. Those symptoms could mean that leukemia has spread to the brain.
  • A biopsy of a lymph node or other tissues, to look for leukemia cells.

Treatment Overview

The goal of treatment for leukemia is to destroy the leukemia cells and allow normal cells to form in your bone marrow. Treatment decisions are based on the kind of leukemia you have, its stage, and your age and general health.

Treatment for acute leukemia

For ALL

Most treatment plans for acute lymphoblastic leukemia (ALL) have 3 steps. These are induction, consolidation, and maintenance.

  • Induction therapy kills leukemia cells in the blood and bone marrow to induce remission. Treatments include chemotherapy and corticosteroids. Induction usually lasts 4 weeks and is done in a hospital. But some people who have ALL have leukemia cells with a certain gene change. This gene is called the Philadelphia chromosome. These people will be treated with a tyrosine kinase inhibitor.
  • Consolidation therapy kills any leukemia cells that may be present even though they don't show up in tests. If these cells regrow, they could cause a relapse. Treatments include more chemotherapy and may include stem cell transplant. This step may also include preventive treatment of the brain or spinal cord with radiation or chemotherapy. Consolidation usually takes several months but doesn't require staying overnight in the hospital.
  • Maintenance therapy also prevents any remaining leukemia cells from growing. This may be done using lower doses of chemotherapy than those used during induction or consolidation. Chemotherapy is given with pills and once-a-month intravenous (IV) treatment. Maintenance is often continued for up to 3 years, but during this time, most people are able to go back to being as active as they were before beginning treatment.

When there are no signs of leukemia for 5 years, a person is usually considered cured. But if the leukemia doesn't go into remission, or if it comes back within the first few years, treatments may include more chemotherapy, a stem cell transplant, or joining a clinical trial for new treatments.

For AML

Treatment for acute myelogenous leukemia (AML) will be based on the genetic makeup of your abnormal myeloid cells. This plan usually has 2 steps that includes induction of remission and post-remission therapy.

  • Induction of remission kills leukemia cells in the blood and bone marrow to induce remission. Chemotherapy is given by intravenous (IV) treatment. Induction usually lasts 4 weeks, with a week of chemotherapy and then 3 weeks for bone marrow recovery. During this month you will be in a hospital.
  • Post-remission therapy kills any leukemia cells that may be present even though they don't show up in tests. This therapy may involve getting additional chemotherapy or a stem cell transplant. Or your doctor may recommend that you join a clinical trial for new treatments. Chemotherapy may be given to you in the hospital for several days each month for 3 to 4 months.
  • If you have a subtype of AML called acute promyelocytic leukemia, you may get other medicines, such as arsenic trioxide and all-trans retinoic acid (ATRA).

Stem cell transplants and chemotherapy are also used when leukemia doesn't respond to treatment or if AML comes back after you haven't had symptoms for a period of time.

To learn more about treatment of acute leukemia, see Medications and Other Treatment.

Treatment of chronic leukemia

For CLL

Chronic lymphocytic leukemia (CLL) isn't always treated right away.

Treatment choices for CLL include:

When CLL doesn't respond to treatment, or if it comes back after you haven't had symptoms for a period of time, you may be treated with more chemotherapy or a stem cell transplant. Or your doctor may recommend that you join a clinical trial for new treatments.

When you have CLL, your body isn't able to fight infections very well. You and your doctor need to watch for any signs of infections, such as pneumonia or yeast infections. Early treatment of these and other infections will help you live longer. You can sometimes prevent certain infections or keep from getting very sick by getting a flu shot or a pneumonia vaccine. Your doctor also may give you antibiotics to prevent infection while you are being treated for leukemia.

For CML

Chronic myelogenous leukemia (CML) is treated right away. The most common choices include:

  • Targeted therapy with a tyrosine kinase inhibitor. This is the first treatment used for CML.
  • Stem cell transplant. Before the transplant can be done, chemotherapy or radiation is used to destroy the bone marrow activity.

For newly diagnosed people in the beginning stages of CML (chronic phase), a tyrosine kinase inhibitor may work for many years. If they don't have a relapse, they may never need to have a stem cell transplant. But if they have a relapse, they may need to have a stem cell transplant.

For people who are diagnosed with CML in the later stages (accelerated or blast crisis phase), treatment may involve having chemotherapy or a tyrosine kinase inhibitor before having a stem cell transplant. This can increase the chances of a successful transplant.

Additional information about leukemia is provided by the National Cancer Institute.

  • For Adult Acute Lymphoblastic Leukemia, see www.cancer.gov/cancertopics/pdq/treatment/adultALL/Patient.
  • For Adult Acute Myeloid Leukemia, see www.cancer.gov/cancertopics/pdq/treatment/adultAML/Patient.
  • For Chronic Lymphocytic Leukemia, see www.cancer.gov/cancertopics/pdq/treatment/CLL/Patient.
  • For Chronic Myelogenous Leukemia, see www.cancer.gov/cancertopics/pdq/treatment/CML/Patient.
  • For Hairy Cell Leukemia, see www.cancer.gov/cancertopics/pdq/treatment/hairy-cell-leukemia/Patient.

Clinical trials

Clinical trials play a very important part in the treatment of leukemia. Clinical trials test the latest drugs and other new treatments. They have made it possible for many people who have leukemia to live longer. People who are in clinical trials get all the recommended treatments for their cancer and are closely watched.

Talk to your doctor about whether there is a clinical trial that might be good for you. For more information, see www.cancer.gov/clinical_trials/ or http://clinicaltrials.gov.

Leukemia in children

Treatments for children who have leukemia aren't the same as treatments for adults who have leukemia. After the leukemia has been treated, children may need to be monitored for treatment side effects that may appear months or years later.

For childhood ALL

Acute lymphoblastic leukemia (ALL) is the most common leukemia in children. Treatments for ALL in children aren't the same as treatments for adults, and are different for infants, children, and adolescents. Treatments include chemotherapy, radiation therapy, chemotherapy with stem cell transplant, and targeted therapy.

For childhood AML and other myeloid diseases

Acute myelogenous leukemia (AML) in children is grouped with other myeloid diseases that affect the blood and bone marrow, including chronic myelogenous leukemia. Treatment for each type is different, but include chemotherapy, radiation therapy, stem cell transplant, and targeted therapy.

Additional information about childhood leukemia is provided by the National Cancer Institute.

  • For Childhood Acute Lymphoblastic Leukemia, see www.cancer.gov/cancertopics/pdq/treatment/childALL/Patient.
  • For Childhood Acute Myeloid Leukemia and Other Myeloid Malignancies, see www.cancer.gov/cancertopics/pdq/treatment/childAML/Patient.

Palliative care

Palliative care is a kind of care for people who have a serious illness. It's different from care to cure your illness. Its goal is to improve your quality of life—not just in your body but also in your mind and spirit. You can have this care along with treatment to cure your illness.

Palliative care providers will work to help control pain or side effects. They may help you decide what treatment you want or don't want. And they can help your loved ones understand how to support you.

If you're interested in palliative care, talk to your doctor.

For more information, see the topic Palliative Care.

End-of-life care

For some people who have advanced cancer, a time comes when treatment to cure the cancer no longer seems like a good choice. This can be because the side effects, time, and costs of treatment are greater than the promise of cure or relief. But you can still get treatment to make you as comfortable as possible during the time you have left. You and your doctor can decide when you may be ready for hospice care.

For more information, see the topics:

Prevention

There is no known way to prevent most types of leukemia.

Some types of leukemia may be prevented by avoiding high doses of radiation, exposure to the chemical benzene, smoking and other tobacco use, or certain types of chemotherapy used to treat other types of cancer.

Home Treatment

You can do things at home to help manage your side effects. If your doctor has given you instructions or medicines to treat these symptoms, be sure to follow them. In general, healthy habits such as eating a balanced diet and getting enough sleep and exercise may help control your symptoms.

  • Home treatment for nausea or vomiting includes watching for and treating early signs of dehydration, such as a dry mouth or feeling lightheaded when you stand up. Eating smaller meals may help. A little bit of ginger candy or ginger tea can help too.
  • Home treatment for diarrhea includes resting your stomach and being alert for signs of dehydration. Check with your doctor before you use any nonprescription medicines for your diarrhea.
  • Home treatment for constipation includes gentle exercise along with drinking enough fluids and eating a diet that is high in fruits, vegetables, and fiber. Check with your doctor before you use a laxative for your constipation.

Other problems that can be treated at home include:

  • Sleep problems. If you have trouble sleeping, going to bed at a regular time and getting exercise daily are some things that can help.
  • Feeling very tired. If you lack energy or become weak easily, try to manage your energy and get extra rest.
  • Hair loss. Tips include using a mild shampoo and a soft hairbrush.
  • Pain. Home treatment can help you manage pain.

Handling the stress of having cancer

Having cancer can be very stressful. It may feel overwhelming to face the challenges in front of you. Finding new ways of coping with the symptoms of stress may improve your overall quality of life.

These ideas may help:

  • Get the support you need. Spend time with people who care about you, and let them help you.
  • Take good care of yourself. Get plenty of rest, and eat nourishing foods.
  • Talk about your feelings. Find a support group where you can share your experience.
  • Try new ways to relax. And do things each day that help you stay calm and relaxed. Stress reduction techniques may help.

Having cancer can change your life in many ways. For support in managing these changes, see the topic Getting Support When You Have Cancer.

Medications

Chemotherapy is the standard treatment for many types of leukemia. Even when a cure isn't possible, chemotherapy may help you live longer and feel better.

Chemotherapy for leukemia is usually a combination of drugs. This is because different drugs attack leukemia cells in different ways. The combination also helps keep the leukemia cells from becoming resistant to any one drug.

Along with the chemotherapy drugs, other medicines may be given to help the chemotherapy drugs work better and prevent infection or bleeding. These drugs include epoetin and hematopoietic stimulants.

Some types of acute leukemia spread to the brain and spinal cord. Regular chemotherapy can't reach those areas, because your body puts up a special barrier to protect them. A different way of giving chemotherapy, called intrathecal chemotherapy, treats these areas by injecting the drugs directly into your spinal canal to attack any leukemia cells there.

Medicine choices

For acute leukemia

Your treatment plan will include the kind of medicine that works best for the specific type or subtype of leukemia that you have.

  • Acute lymphoblastic leukemia (ALL) may be treated with medicines, such as chemotherapy, corticosteroids, and biologics.
  • Acute myelogenous leukemia (AML) may be treated with medicines, such as chemotherapy.
  • Acute promyelocytic leukemia (APL) may be treated with medicines, such as chemotherapy, arsenic trioxide, and all-trans-retinoic acid (ATRA).

For chronic leukemia

  • Chronic lymphocytic leukemia (CLL) may be treated with medicines, such as chemotherapy, corticosteroids, and monoclonal antibodies.
  • Chronic myelogenous leukemia (CML) may be treated with medicines, such as chemotherapy and tyrosine kinase inhibitors.

Medicines used for treatments for chronic lymphocytic leukemia (CLL) are taken orally (by mouth) or given intravenously for limited periods of time. If there is relapse, medicines are given again.

For chronic myelogenous leukemia (CML), medicine is usually taken by mouth for as long as needed.

Medicine for nausea and vomiting

Nausea and vomiting are common side effects of chemotherapy. They usually go away when treatment stops. Your doctor will prescribe medicines to help relieve nausea.

Surgery

In rare cases of chronic lymphocytic leukemia (CLL), the spleen needs to be removed. This happens when the spleen is destroying red blood cells and platelets. The operation is called a splenectomy.

Often a swollen lymph node will be removed to confirm the diagnosis of leukemia. This operation is called a lymphadenectomy.

Surgery is sometimes needed to place a central venous catheter into a large vein in the chest. The catheter is a small tube that is used to give you chemotherapy and other drugs. The tube can also be used to take samples of blood or for giving blood transfusions when needed. It prevents the need for many needle sticks during treatment.

Other Treatment

  • Radiation therapy may be used to destroy cancer cells and shrink tumors. Radiation can be applied to one area or to the whole body. Sometimes it is used to treat leukemia that has spread to the brain and central nervous system or to prevent this spread. It also may be used to shrink swollen lymph nodes or to prepare your body for a bone marrow transplant.
  • Stem cell transplant may be used to replace damaged stem cells with new, normal stem cells. Most transplants done for leukemia are allogeneic. This means that the stem cells are donated by someone else. Transplants can also be autologous. This means that the stem cells come from your own body.

Complementary therapy

People sometimes use complementary therapies along with medical treatment to help relieve symptoms and side effects of cancer treatments. Some of the complementary therapies that may be helpful include:

Mind-body treatments like the ones listed above may help you feel better. They can make it easier to cope with cancer treatments. They also may reduce chronic low back pain, joint pain, headaches, and pain from treatments.

Before you try a complementary therapy, it is very important to talk to your doctor about the possible value and potential side effects. Let your doctor know if you are already using any such therapies. Complementary therapies aren't meant to take the place of standard medical treatment. But they may improve your quality of life and help you deal with the stress and side effects of cancer treatment.

References

Other Works Consulted

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  • National Cancer Institute (2012). Adult Acute Chronic Lymphoblastic Leukemia Treatment (PDQ)—Health Professional Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/adultALL/healthprofessional.
  • National Cancer Institute (2012). Adult Acute Lymphoblastic Leukemia Treatment (PDQ)—Patient Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/adultALL/Patient.
  • National Cancer Institute (2012). Adult Acute Myeloid Leukemia Treatment (PDQ)—Health Professional Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/adultAML/healthprofessional.
  • National Cancer Institute (2012). Adult Acute Myeloid Leukemia Treatment (PDQ)—Patient Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/adultAML/patient.
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  • National Cancer Institute (2012). Childhood Acute Myeloid Leukemia/Other Myeloid Malignancies Treatment (PDQ)—Health Professional Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/childAML/healthprofessional.
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  • National Cancer Institute (2012). Chronic Myelogenous Leukemia Treatment (PDQ)—Health Professional Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/CML/healthprofessional.
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