Leukemia - EosinophilicLast Updated: June 16, 2011 This section has been reviewed and approved by the Cancer.Net Editorial Board, 04/11 Overview
Leukemia is a cancer of the blood cells. Leukemia begins when normal blood cells change and grow uncontrollably. Blood cells are produced in the bone marrow, the spongy tissue inside the larger bones in the body. There are different types of blood cells, including red blood cells that carry oxygen throughout the body, white cells that fight infection, and platelets that help the blood to clot. Abnormalities (changes) in the bone marrow cells can cause too many or too few of certain blood cells. There are four main types of leukemia in adults:
About eosinophilic leukemia Eosinophilia is a condition that develops when the bone marrow makes too many eosinophils, a type of white blood cell involved in allergic reactions or used to fight certain parasites. Chronic eosinophilic leukemia is a subtype of clonal eosinophilia, meaning it is caused by a new genetic change. It is sometimes called hypereosinophilic syndrome (HES). This disease is classified as a myeloproliferative disorder (myelo- means bone marrow and proliferative means too much). People can also have many eosinophils without having cancer. For example, sometimes the body makes too many eosinophils in response to an allergen or a parasite. This type of eosinophilia is called secondary eosinophilia and is much more common than eosinophilic leukemia. This section focuses on chronic eosinophilic leukemia. Acute eosinophilic leukemia is rare and is treated similarly to acute myeloid leukemia (AML). Find out more about basic cancer terms used in this section. Looking for More of an Overview? If you would like additional introductory information, explore this related item on Cancer.Net:
Or, choose “Next” (below, right) to continue reading this detailed section. To select a specific topic within this section, use the icon panel located on the right side of your screen. Statistics
Eosinophilic leukemia is rare; no specific statistics are available. Risk Factors
A risk factor is anything that increases a person’s chance of developing cancer. Although risk factors can influence the development of leukemia, most do not directly cause leukemia. Some people with several risk factors never develop leukemia, while others with no known risk factors do. However, knowing your risk factors and talking about them with your doctor may help you make more informed lifestyle and health care choices. Leukemia can be caused by a genetic mutation (change) that is inherited (passed from generation to generation within a family) or develops during a person’s life because of environmental factors, smoking, and chemical or radiation exposure. However, no specific cause can be found for most patients with leukemia. The specific cause of eosinophilic leukemia is not known. Symptoms and Signs
People with eosinophilic leukemia may experience the following symptoms or signs. Sometimes, people with eosinophilic leukemia do not show any of these symptoms. Or, these symptoms may be caused by a medical condition that is not cancer. If you are concerned about a symptom or sign on this list, please talk with your doctor.
Your doctor will ask you questions about the symptoms you are experiencing to help find out the cause of the problem, called a diagnosis. This may include how long you’ve been experiencing the symptoms(s) and how often. If leukemia is diagnosed, relieving symptoms and side effects remains an important part of care and treatment. This may also be called symptom management, palliative care, or supportive care. Be sure to talk with your health care team about symptoms you experience, including any new symptoms or a change in symptoms. Diagnosis
Doctors use many tests to diagnose eosinophilia. Although a patient’s signs and symptoms may cause a doctor to suspect eosinophilic leukemia, it is diagnosed only by testing a patient’s blood and bone marrow. Some tests may also help doctors decide which treatments may be the most effective. Your doctor may consider these factors when choosing a diagnostic test:
The main criteria for diagnosing eosinophilic leukemia are:
In addition to a physical examination, the following tests may be used to diagnose eosinophilic leukemia: Blood tests. The diagnosis of eosinophilic leukemia begins with a test called a complete blood count (CBC), which measures the number of different types of cells in a person's blood. If the blood contains many eosinophils (see criteria above), eosinophilic leukemia is suspected. Bone marrow biopsy and aspiration. These two procedures are similar and often done at the same time. Bone marrow has both a solid and liquid part. A bone marrow biopsy is the removal of a small amount of solid tissue using a needle. An aspiration removes a sample of fluid with a needle. The sample(s) are then analyzed by a pathologist (a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease) to determine the number and type of abnormal cells. A common site for a bone marrow biopsy and aspiration is the pelvic bone, which is located in the lower back by the hip. The skin is usually numbed with medication beforehand, and other types of anesthesia may be used. Many immature cells, called blasts, indicate acute rather than chronic eosinophilic leukemia. Acute eosinophilic leukemia is not covered in this article and is treated similarly to AML. Testing leukemia genetics. If many eosinophils are found, a molecular genetic analysis should be done to test for a mutation that makes an abnormal protein known as FIP1-like-1/platelet-derived growth factor alpha. This genetic testing helps doctors decide which type of treatment should be given (see Treatment). Immunophenotyping. Immunophenotyping is the examination of the proteins on the surface of the leukemia cells and helps the doctor to confirm the exact type of leukemia. Cytogenetics. Cytogenetics is the examination of the leukemia cells for chromosome (long strand of genes) abnormalities. It also helps the doctor confirm the diagnosis and may help to determine the person’s prognosis (chance of recovery). Computed tomography (CT or CAT) scan. A CT scan creates a three-dimensional picture of the inside of the body with an x-ray machine. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. Sometimes, a contrast medium (a special dye) is injected into a patient’s vein to provide better detail. A CT scan also shows enlarged lymph nodes or a swollen spleen or liver. Evaluation of the heart. People who have many eosinophils for a long period of time often have problems with heart function and rhythm. The doctor may recommend an electrocardiogram (ECG or EKG, a noninvasive test that looks for abnormal heart rhythms or heart damage) and/or an echocardiogram (a noninvasive test that looks the structure and function of the heart using sound waves and an electronic sensor). Learn more about what to expect when having common tests, procedures, and scans. After these diagnostic tests are done, your doctor will review all of the results with you. If the diagnosis is leukemia, these results also help the doctor describe the disease. Learn more about the first steps to take after a diagnosis of leukemia. Staging
Staging is a way of describing a cancer, such as where it is located, if or where it has spread, and whether it is affecting the functions of other organs in the body. Doctors use diagnostic tests to determine the cancer's stage, so staging may not be complete until all of the tests are finished. Knowing the stage helps the doctor to decide what kind of treatment is best and can help predict a patient's prognosis. There are different stage descriptions for different types of cancer. Unlike most solid tumors, leukemias do not have a formal staging system. Regular blood tests (see Diagnosis) are the main ways to monitor a person’s recovery from eosinophilic leukemia, including any symptoms related to the disease and the number of immature cells in the bone marrow. Treatment
This section outlines treatments that are the standard of care (the best proven treatments available) for this specific type of leukemia. When making treatment plan decisions, patients are also encouraged to consider clinical trials as an option. A clinical trial is a research study to test a new treatment to evaluate whether it is safe, effective, and possibly better than standard treatment. Your doctor can help you review all treatment options. For more information, see the Clinical Trials and Current Research sections. Treatment overview For leukemia, different types of doctors often work together to create a patient’s overall treatment plan that combines different types of treatments. This is called a multidisciplinary team. According to the National Cancer Institute, the best treatment for eosinophilic leukemia remains unclear. As explained in the Overview, eosinophilic leukemia is classified as a myeloproliferative disorder. Descriptions of the most common treatment options for a myeloproliferative disorder are listed below. Treatment options and recommendations depend on several factors, including the type of leukemia, possible side effects, and the patient’s preferences and overall health. Usually, myeloproliferative disorders cannot be cured, but treatment helps to control the symptoms. Learn more about making treatment decisions. Chemotherapy Chemotherapy is the use of drugs to kill cancer cells, usually by stopping the cancer cells’ ability to grow and divide. Systemic chemotherapy is delivered through the bloodstream to reach cancer cells throughout the body. Chemotherapy is given by a medical oncologist, a doctor who specializes in treating cancer with medication, or a hematologist, a doctor who specializes in treating blood disorders. A chemotherapy regimen (schedule) usually consists of a specific number of cycles given over a set period of time. A patient may receive one drug at a time or combinations of different drugs at the same time. Chemotherapy used to treat eosinophilic leukemia includes hydroxyurea (Droxia, Hydrea), cyclophosphamide (Clafen, Cytoxan, Neosar), and vincristine (Vincasar, Oncovin). The side effects of chemotherapy depend on the individual and the dose used, but they can include fatigue, risk of infection, nausea and vomiting, loss of appetite, and diarrhea. These side effects usually go away once treatment is finished. Learn more about chemotherapy and preparing for treatment. The medications used to treat cancer are continually being evaluated. Talking with your doctor is often the best way to learn about the medications prescribed for you, their purpose, and their potential side effects or interactions with other medications. Learn more about your prescriptions by using searchable drug databases. Surgery Surgery to remove the spleen (called a splenectomy), which also makes white blood cells, may be recommended for some patients. A surgical oncologist is a doctor who specializes in treating cancer using surgery. Learn more about surgery. Immunotherapy Immunotherapy (also called biologic therapy), is designed to boost the body's natural defenses to fight the cancer. It uses materials made either by the body or in a laboratory to bolster, target, or restore immune system function. Recombinant interferon alpha (Alferon, Roferon-A, Intron A) is a biologic therapy that is occasionally used to treat eosinophilic leukemia. Learn more about immunotherapy. Targeted therapy Targeted therapy is a treatment that targets the cancer’s specific genes, proteins, or the tissue environment that contributes to cancer growth and survival. This type of treatment blocks the growth and spread of cancer cells while limiting damage to normal cells, usually leading to fewer side effects than other cancer medications. Recent studies show that not all cancers have the same targets. To find the most effective treatment, your doctor may run tests to identify the genes, proteins, and other factors involved in your leukemia. As a result, doctors can better match each patient with the most effective treatment whenever possible. In addition, many research studies are taking place now to find out more about specific molecular targets and new treatments directed at them. Learn more about targeted treatments. In many patients with hypereosinophilic syndrome, the leukemia cells have a specific genetic change that makes an abnormal protein (called the FIP1-like-1/platelet-derived growth factor alpha) that stimulates the cells to grow. Imatinib (Gleevec) is a drug that stops enzymes called tyrosine kinases from working and can kill abnormal eosinophils by keeping the FIP1-like-1-platelet-derived growth factor alpha protein from working. Imatinib is more likely to work for patients who have this mutation; however, if a patient does not have this mutation, there is still a possibility that the drug will work. The main side effects of imatinib include swelling around the eyes, leg swelling, muscle cramping, headache, fatigue, rash, and musculoskeletal (joint) pain. If this treatment works, it is often continued throughout a person’s lifetime. Steroids Steroid medications are used to control some symptoms of eosinophilic leukemia. Radiation therapy Radiation therapy is the use of high-energy x-rays or other particles to kill cancer cells. A doctor who specializes in giving radiation therapy to treat cancer is called a radiation oncologist. The most common type of radiation therapy is called external-beam radiation therapy, which is radiation given from a machine outside the body. When radiation therapy is given using implants, it is called internal radiation therapy or brachytherapy. A radiation therapy regimen (schedule) usually consists of a specific number of treatments given over a set period of time. Radiation therapy for eosinophilic leukemia is generally used as a palliative treatment, meaning it is given to improve a patient’s quality of life by treating the symptoms and side effects of the cancer or cancer treatment. Side effects from radiation therapy include fatigue, mild skin reactions, upset stomach, and loose bowel movements. Most side effects go away soon after treatment is finished. Learn more about radiation therapy. Stem cell transplantation A stem cell transplant is a medical procedure in which diseased bone marrow is replaced by highly specialized cells, called hematopoietic stem cells. Hematopoietic stem cells are found both in the bloodstream and in the bone marrow. Today, this procedure is more commonly called a stem cell transplant, rather than bone marrow transplant, because it is the blood stem cells that are typically being transplanted, not the actual bone marrow tissue. Before recommending transplantation, doctors will talk with the patient about the risks of this treatment and consider several other factors, such as the type of cancer, results of any previous treatment, and the patient’s age and general health. Transplantation is a higher-risk treatment and is not used often for people with eosinophilic leukemia because it is not always effective for this disease and because many patients with this disease are older and the risks of the procedure are higher. There are two types of stem cell transplantation depending on the source of the replacement blood stem cells: allogeneic (ALLO) and autologous (AUTO). In an AUTO transplant, the patient’s own stem cells are used. The stem cells are obtained from the patient when he or she is in remission (absence of leukemia symptoms; also called “no evidence of disease” or NED) from previous treatment. The stem cells are then frozen until they are needed, usually after the high-dose treatment (explained below) is completed. In both types, the goal of transplantation is to destroy cancer cells in the marrow, blood, and other parts of the body and allow replacement blood stem cells create healthy bone marrow. In most stem cell transplants, the patient is treated with high doses of chemotherapy and/or radiation therapy to destroy as many cancer cells as possible. This also destroys the patient’s bone marrow tissue and suppresses the patient’s immune system so that, in an ALLO transplant, the donor cells are not rejected by the body. After the high-dose treatment is given, blood stem cells are infused into the patient’s vein to replace the bone marrow and restore normal blood counts from donor cells. Sometimes, ALLO transplants can also be performed after giving lower doses of chemotherapy and/or radiation therapy that are still sufficient to suppress the immune system and allow growth of the donor cells. (These transplants, sometimes termed “mini-transplants” or reduced intensity transplants have less immediate side effects, allowing the procedure to be used for older patients.) In an ALLO transplant, another major risk is that the donor’s cells will recognize the patient’s body as foreign, causing graft-versus-host disease (GVHD). GVHD may be a serious complication of allogeneic transplants and can be fatal. Other side effects may include liver problems, diarrhea, infections, and rashes. However, GVHD can also be a benefit because the donor cells can recognize the cancer cells as foreign and destroy these cells, a mechanism that is one of the major reasons why ALLO transplantation generally works so well over the long term. The risk of GVHD can be reduced with exact HLA-type matching and the use of preventive drugs. In an AUTO transplant, there is little risk of GVHD because the replacement stem cells are the patient’s own cells. However, there is a risk in an autologous transplant that some of the cells that are put back into the patient could still be cancerous. Learn more about bone marrow and stem cell transplantation. Recurrent eosinophilic leukemia Once your treatment is complete and there is a remission, talk with your doctor about the possibility of the leukemia returning. Many survivors feel worried or anxious that the leukemia will come back. Learn more about coping with this fear. If the leukemia does return after the original treatment, it is called recurrent leukemia. When this occurs, a cycle of testing will begin again to learn as much as possible about the recurrence. After testing is done, you and your doctor will talk about your treatment options. Often the treatment plan will include the therapies described above (such as chemotherapy, immunotherapy, targeted therapy, and stem cell transplantation) but may be used in a different combination or given at a different pace. Your doctor may also suggest clinical trials that are studying new ways to treat this type of recurrent leukemia. People with recurrent leukemia often experience emotions such as disbelief or fear. Patients are encouraged to talk with their health care team about these feelings and ask about support services to help them cope. Learn more about dealing with cancer recurrence. Refractory leukemia If the leukemia continues to worsen despite treatment, it is called refractory leukemia. Patients with this diagnosis are encouraged to talk with doctors who are experienced in treating this type of leukemia, because there can be different opinions about the best treatment plan. Learn more about seeking a second opinion before starting treatment, so you are comfortable with the treatment plan chosen. This discussion may include clinical trials studying new treatments. In addition to treatment to slow, stop, or eliminate the leukemia (also called disease-directed treatment), an important part of care is relieving a person’s symptoms and side effects. It includes supporting the patient with his or her physical, emotional, and social needs, an approach called palliative or supportive care. People often receive disease-directed therapy and treatment to ease symptoms at the same time. If disease-directed treatment is not successful, then further therapy may not be recommended. This situation is very stressful, and it may be difficult to discuss. However, it is important to have open and honest conversations with your doctor and health care team to express your feelings, preferences, and concerns. The health care team is there to help, and many team members have special skills, experience, and knowledge to support patients and their families. Learn more about advanced care planning. Find out more about common terms used during cancer treatment. About Clinical Trials
Doctors and scientists are always looking for better ways to treat patients with eosinophilic leukemia. To make scientific advances, doctors create research studies involving people, called clinical trials. Many clinical trials are focused on new treatments, evaluating whether a new treatment is safe, effective, and possibly better than the current (standard) treatment. These types of studies evaluate new drugs, different combinations of existing treatments, new approaches to radiation therapy or surgery, and new methods of treatment. Patients who participate in clinical trials are often among the first to receive new treatments before they are widely available. However, there is no guarantee that the new treatment will be safe, effective, or better than a standard treatment. There are also clinical trials that study new ways to ease symptoms and side effects during treatment and manage the late effects that may occur after treatment. Talk with your doctor about clinical trials regarding side effects. In addition, there are ongoing studies about ways to prevent the disease. Patients decide to participate in clinical trials for many reasons. For some patients, a clinical trial is the best treatment option available. Because standard treatments are not perfect, patients are often willing to face the added uncertainty of a clinical trial in the hope of a better result. Other patients volunteer for clinical trials because they know that these studies are the only way to make progress in treating eosinophilic leukemia. Even if they do not benefit directly from the clinical trial, their participation may benefit future patients with eosinophilic leukemia. Sometimes people have concerns that, by participating in a clinical trial, they may receive no treatment by being given a placebo or a “sugar pill.” The use of placebos in cancer clinical trials is rare. When a placebo is used in a study, it is done with the full knowledge of the participants. Find out more about placebos in cancer clinical trials. To join a clinical trial, patients must participate in a process known as informed consent. During informed consent, the doctor should list all of the patient’s options, so that the person understands how the new treatment differs from the standard treatment. The doctor must also list all of the risks of the new treatment, which may or may not be different from the risks of standard treatment. Finally, the doctor must explain what will be required of each patient in order to participate in the clinical trial, including the number of doctor visits, tests, and the schedule of treatment. Learn more about clinical trials, including patient safety, phases of a clinical trial, deciding to participate in a clinical trial, questions to ask the research team, and links to find cancer clinical trials. For specific topics being studied for eosinophilic leukemia, learn more in the Current Research section. Patients who participate in a clinical trial may stop participating at any time for any personal or medical reason. This may include that the new treatment is not working or there are serious side effects. It is important that patients participating in a clinical trial talk with their doctor and researchers about who will be providing their treatment and care during the clinical trial, after the clinical trial ends, and/or if the patient chooses to leave the clinical trials before it ends. Side Effects
Cancer and its treatment can cause a variety of side effects. However, doctors have made major strides in recent years in reducing pain, nausea and vomiting, and other physical side effects of cancer treatments. Many treatments used today are less intensive but as effective as treatments used in the past. Doctors also have many ways to provide relief to patients when such side effects occur. Fear of treatment side effects is common after a diagnosis of cancer, but it may be helpful to know that preventing and controlling side effects is a major focus of your health care team. Before treatment begins, talk with your doctor about possible side effects of the specific treatments you will be receiving. The specific side effects that can occur depend on a variety of factors, including the type of cancer, its location, the individual treatment plan (including the length and dosage of treatment), and your overall health. Common side effects for each treatment option are described in detail within the Treatment section. Ask your doctor which side effects are most likely to happen (and which are not), when side effects are likely to occur, and how they will be addressed by the health care team. Also, be sure to communicate with the doctor about side effects you experience during and after treatment. Care of a patient’s symptoms and side effects is an important part of a person’s overall treatment plan; this is called palliative or supportive care. It helps people with cancer at any stage of illness be as comfortable as possible. Learn more about the most common side effects of eosinophilic leukemia and different treatments, along with ways to prevent or control them. Be sure to talk with your doctor about the level of caregiving you may need during treatment and recovery, as family members and friends often play an important role in the care of a person with eosinophilic leukemia. Learn more about caregiving. In addition to physical side effects, there may be psychosocial (emotional and social) effects as well. For many patients, a diagnosis of eosinophilic leukemia is stressful and can bring difficult emotions. Patients and their families are encouraged to share their feelings with a member of their health care team, who can help with coping strategies. Learn more about the importance of addressing such needs, including concerns about managing the cost of your medical care. A side effect that occurs more than five years after treatment is called a late effect. Treatment of late effects is an important part of survivorship care. Learn more about late effects or long-term side effects by reading the After Treatment section or talking with your doctor. After Treatment
After treatment for eosinophilic leukemia ends, talk with your doctor about developing a follow-up care plan. This plan may include regular physical examinations, blood tests, bone marrow biopsies, and possibly scans or other imaging studies to monitor your recovery for the coming months and years. People experiencing a long-term remission are encouraged to follow cancer screening recommendations for the general population. Some cancer treatments may cause the following long-term side effects. It’s important to talk with your health care team about the best ways to watch for these side effects and what will be done if they do occur.
ASCO offers treatment summary forms to help keep track of the treatment you received and develop a survivorship care plan once treatment is completed. People recovering from eosinophilic leukemia are encouraged to follow established guidelines for good health, such as maintaining a healthy weight, not smoking, eating a balanced diet, and having recommended cancer screening tests. Talk with your doctor to develop a plan that is best for your needs. Moderate physical activity can help rebuild your strength and energy level. Your doctor can help you create an appropriate exercise plan based upon your needs, physical abilities, and fitness level. Learn more about the next steps to take in survivorship, including making positive lifestyle changes. Find out more about common terms used after cancer treatment is complete. Current Research
Doctors are working to learn more about eosinophilic leukemia, ways to prevent it, how to best treat it, and how to provide the best care to people diagnosed with this disease. The following areas of research may include new options for patients through clinical trials. Always talk with your doctor about the diagnostic and treatment options best for you. Genetic research. Because this type of disorder is usually associated with a genetic mutation, researchers are searching for specific genes or mutations that can indicate cancer. Stem cell/bone marrow transplantation. New approaches for stem cell/bone marrow transplantation are being tested to expand the use of this treatment option. New treatments. Better combinations of chemotherapy and other treatment combinations are also being studied, as is the drug mepolizumab (Bosatria). Early studies have shown that mepolizumab lowers the number of eosinophils for people with allergies and HES, and it has helped control some signs and symptoms of HES. Supportive care. Clinical trials are underway to find better ways of reducing symptoms and side effects of current eosinophilic leukemia treatments in order to improve patients’ comfort and quality of life.To find clinical trials specific to your diagnosis, talk with your doctor or search online clinical trial databases now. Looking for More about Current Research? If you would like additional information about the latest areas of research regarding leukemia, explore these related items:
Or, choose “Next” (below, right) to continue reading this detailed section. Questions to Ask the Doctor
Talking often with the doctor is important to make informed decisions about your health care. These suggested questions are a starting point to help you learn more about your care and treatment. You are also encouraged to ask additional questions that are important to you.
Patient Information Resources
In addition to Cancer.Net, there are other sources of information about this type of cancer available online. Cancer.Net maintains a list of national, not-for-profit organizations that may be helpful in finding additional information, services, and support. As always, be sure to talk with your doctor about questions you may have about information you find about this disease. View organizations that offer information on this specific type of cancer. |
