Treating Aplastic Anemia
The 2 forms of treatment for aplastic anemia are primary and supportive.
PrimaryTreatment
This treatment is directed toward curing the condition. If you are young, allogeneic stem cell transplantation is considered the best option (see the American Cancer Society document, “Bone Marrow and Peripheral Blood Stem Cell Transplants”). In this treatment you will first receive low doses of radiation therapy to your whole body and high doses of chemotherapy. Sometimes only chemotherapy is used. This works best in children and young adults. As people get older, they are less able to tolerate this procedure. Some doctors use age 35 as the cutoff.
Soon after the radiation and/or chemotherapy, you will receive a transfusion with blood-forming stem cells from a donor. The stem cells are obtained either by multiple bone marrow aspirations (while the donor is under general anesthesia) or by a procedure that uses a machine that separates blood cells taken from a large vein, removes the part of the blood containing most of the stem cells, and returns the other cells. This is called apheresis and it has become the most commonly used method. The stem cells are infused through your vein into the blood and then travel to the bone marrow, where they will grow. This treatment is successful about 60% of the time.
Your donor must have a similar “tissue type”(or be immunologically compatible) with you. Most often the best matched donor is a sister or brother. This “matching” is determined by testing in the laboratory. If a matched sister or brother is not available, then stem cells may be used from an unrelated donor or cells stored from umbilical cord blood. A nationwide registry of potential stem cell donors and stored umbilical cord blood has been developed (www.marrow.org).
If you are too old for a transplant or do not have a matched donor then doctors will recommend treatment that suppresses your immune system. Remember that it is your immune system that is probably causing the aplastic anemia.
The major drug that is used is called antithymocyte globulin (ATG). ATG is an antibody produced against human T lymphocytes, a special type of immune white blood cell. The T-lymphocytes are likely destroying the bone marrow stem cells. The ATG is made in either horses or rabbits and purified before being used.
This medicine is given by intravenous injection and decreases the function (suppresses) your immune system. Often a second drug called cyclosporine is added to suppress the immune system. The combination of the 2 treatments is successful about 60% of the time in patients with the most severe disease. This doesn’t mean that the aplastic anemia is cured 60% of the time. Rather some of the time, instead of becoming completely normal, the blood counts rise to a manageable level, which leaves the patient feeling well and able to live a normal life.
Both stem cell transplantation and immune suppression therapy have equal success rates — about 60% — but different side effects. With stem cell transplant patients, the major side effect is graft-versus-host disease. With ATG, the major problem is that after several years, about 15% of patients develop leukemia or a leukemia-like abnormality called myelodysplasia.
Supportive Treatment
While your blood counts are low, you may need transfusions of red blood cells. Since your blood platelets also will be low, you may need platelet transfusions. Because of your low white blood cell count, you may develop an infection and require treatment with antibiotics. Infection is the major cause of death from aplastic anemia. Treatment with antibiotics needs to be started as soon as infection is suspected. Treatment with white blood cell transfusions is not practical. It is not possible to get enough white blood cells from normal donors to raise a person’s white blood cell count.
Drugs can be given to increase the white blood cell count. These are called G-CSF (Neupogen) and GM-CSG (Sargramostim). These work only slightly for most patients with aplastic anemia.
Some patients will have only a mild form of aplastic anemia and can manage without either stem cell transplantation or ATG. Some of these patients can be managed with drugs called androgens. Androgens are male sex hormones that also stimulate blood production. They are the reason that men have higher red blood cell counts than do women. Although they can be effective in treating aplastic anemia, they create major side effects in women. They cause them to develop masculine characteristics such as facial hair growth, balding, deepening voice, etc.
Side Effects of Treatment
Stem cell transplantation is a major procedure with many risks and side effects. The most serious side effects occur during the first few weeks after the transplant. Some people may die during this procedure. With advances in this treatment, however, death from these early side effects is less common.
If you have a transplant, you will develop very low blood counts from the radiation therapy and/or chemotherapy and will need treatments such as red blood cell and platelet transfusions. You can develop nausea, vomiting, diarrhea, and mouth sores from the treatment. Serious infections are also likely to occur and are treated with large doses of antibiotics. These all generally go away in 3 to 4 weeks when the transplanted blood-forming stem cells start to produce normal blood cells. But during this wait, you must stay in the hospital.
Another possible side effect of a stem cell transplant is graft-versus-host disease. This occurs when the transplanted donor cells attack your own cells through an immune reaction. This can lead to skin rashes with severe itching and bowel disturbances such as diarrhea. The immune system is also blocked. Although graft-versus-host disease can be partly controlled with medicines, it can sometimes be very disabling and occasionally, fatal. It occurs more often in older patients, which is one reason to avoid transplants in this group.
The therapies that suppress the immune system (called immunosuppressive therapies) may also have side effects. ATG can cause allergic reactions while it is being given. These take the form of skin rashes or sometimes asthma-like breathing problems. Generally, these side effects can be controlled with medicines. Cyclosporine can damage your kidneys and liver, so if you are being treated with this drug you must be carefully watched. Blood tests will be done often to check kidney and liver function.
Clinical Trials
The purpose of clinical trials: Studies of promising new or experimental treatments in patients are known as clinical trials. A clinical trial is only done when there is some reason to believe that the treatment being studied may be valuable to the patient. Treatments used in clinical trials are often found to have real benefits. Researchers conduct studies of new treatments to answer the following questions:
- Is the treatment helpful?
- How does this new type of treatment work?
- Does it work better than other treatments already available?
- What side effects does the treatment cause?
- Are the side effects greater or less than the standard treatment?
- Do the benefits outweigh the side effects?
- In which patients is the treatment most likely to be helpful?
Types of clinical trials: There are 3 phases of clinical trials in which a treatment is studied before it is eligible for approval by the FDA (Food and Drug Administration).
Phase I clinical trials: The purpose of a phase I study is to find the best way to give a new treatment and how much of it can be given safely. The cancer care team watches patients carefully for any harmful side effects. The treatment has been well tested in lab and animal studies, but the side effects in patients are not completely known. Doctors conducting the clinical trial start by giving very low doses of the drug to the first patients and increasing the dose for later groups of patients until side effects appear. Although doctors are hoping to help patients, the main purpose of a phase I study is to test the safety of the drug.
Phase II clinical trials: These studies are designed to see if the drug works. Patients are given the highest dose that doesn’t cause severe side effects (determined from the phase I study) and closely observed for an effect on the cancer. The cancer care team also looks for side effects.
Phase III clinical trials: Phase III studies involve large numbers of patient ??? often several hundred. One group (the control group) receives the standard (most accepted) treatment. The other group receives the new treatment. All patients in phase III studies are closely watched. The study will be stopped if the side effects of the new treatment are too severe or if one group has had much better results than the others.
If you are in a clinical trial, you will have a team of experts taking care of you and monitoring your progress very carefully. The study is especially designed to pay close attention to you.
However, there are some risks. No one involved in the study knows in advance whether the treatment will work or exactly what side effects will occur. That is what the study is designed to find out. While most side effects disappear in time, some can be permanent or even life threatening. Keep in mind, though, that even standard treatments have side effects. Depending on many factors, you may decide to enroll in a clinical trial.
Deciding to enter a clinical trial: Enrollment in any clinical trial is completely up to you. Your doctors and nurses will explain the study to you in detail and will give you a form to read and sign indicating your desire to take part. This process is known as giving your informed consent. Even after signing the form and after the clinical trial begins, you are free to leave the study at any time, for any reason. Taking part in the study does not prevent you from getting other medical care you may need.
To find out more about clinical trials, ask your cancer care team. Among the questions you should ask are:
- Is there a clinical trial for which I would be eligible?
- What is the purpose of the study?
- What kinds of tests and treatments does the study involve?
- What does this treatment do? Has it been used before?
- Will I know which treatment I receive?
- What is likely to happen in my case with, or without, this new treatment?
- What are my other choices and their advantages and disadvantages?
- How could the study affect my daily life?
- What side effects can I expect from the study? Can the side effects be controlled?
- Will I have to be hospitalized? If so, how often and for how long?
- Will the study cost me anything? Will any of the treatment be free?
- If I am harmed as a result of the research, what treatment would I be entitled to?
- What type of long-term follow-up care is part of the study?
- Has the treatment been used to treat other types of cancers?
The American Cancer Society offers a clinical trials matching service for patients, their family, and friends. You can reach this service at 1-800-303-5691 or on our Web site at http://clinicaltrials.cancer.org. Based on the information you provide about your cancer type, stage, and previous treatments, this service can compile a list of clinical trials that match your medical needs. In finding a center most convenient for you, the service can also take into account where you live and whether you are willing to travel.
You can also get a list of current clinical trials by calling the National Cancer Institute’s Cancer Information Service toll free at 1-800-4-CANCER or by visiting the NCI clinical trials Web site at http://www.cancer.gov/clinicaltrials.
Complementary and Alternative Therapies
Complementary and alternative therapies are a diverse group of health care practices, systems, and products that are not part of usual medical treatment. They may include products such as vitamins, herbs, or dietary supplements, or procedures such as acupuncture, massage, and a host of other types of treatment. There is a great deal of interest today in complementary and alternative treatments for cancer. Many are now being studied to find out if they are truly helpful to people with cancer.
You may hear about different treatments from family, friends, and others, which may be offered as a way to treat your cancer or to help you feel better. Some of these treatments are harmless in certain situations, while others have been shown to cause harm. Most of them are of unproven benefit.
The American Cancer Society defines complementary medicine or methods as those that are used along with your regular medical care. If these treatments are carefully managed, they may add to your comfort and well-being. Alternative medicines are defined as those that are used instead of your regular medical care. Some of them have been proven not to be useful or even to be harmful, but are still promoted as ?cures.? If you choose to use these alternatives, they may reduce your chance of fighting your cancer by delaying, replacing, or interfering with regular cancer treatment.
Before changing your treatment or adding any of these methods, discuss this openly with your doctor or nurse. Some methods can be safely used along with standard medical treatment. Others, however, can interfere with standard treatment or cause serious side effects. That is why it’s important to talk with your doctor.