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This is the second article in a two-part series on bone marrow and stem cell transplantation. It outlines common side effects of this treatment. Part I provides an overview, including the various types of bone marrow and stem cell transplantation. ASCO member Edward Agura, MD, Director of the Program in Blood and Marrow Transplant at Baylor University Medical Center in Dallas, Texas, contributed to these articles.
Although it is an effective treatment for several types of cancer, bone marrow and stem cell transplantationâlike other cancer treatmentsâcan cause side effects. The types and intensity of side effects vary from person to person and with the type of transplant, the person's health, and other factors.
Doctors and scientists are continually working to identify treatment methods that have fewer side effects. Your health care team will work with you to ease or prevent any side effects that occur. This is called symptom management or supportive care. Be sure to talk with your health care team about any symptoms you experience, including new symptoms or a change in symptoms.
Side effects of bone marrow and stem cell transplantation include the following.
We live in a world surrounded by living microscopic organisms, including bacteria, viruses, and fungi. Many of these are beneficial, but some are dangerous, even for people with a healthy immune system. The chemotherapy and/or radiation therapy given before stem cell transplantation weakens the patient's immune system, lowering the body's defenses against these organisms. Stem cell recipients are, therefore, especially vulnerable to infection during this early period of treatment.
One common misconception is that the greatest risk of early infection comes from outside the patient's own bodyâfrom visitors, foods, and other sources. However, this is not true. Most infections that occur during the first few weeks of a transplant are due to organisms that are already in the patient's body, hiding in places such as the lung, sinuses, skin, and the intestines. They cause infection during a period of low immunity. Fortunately, most of these infections are relatively easy to treat with modern antibiotics. The reduced immunity of the early transplant period lasts about two weeks, after which the immune system is back to near full-fighting strength and can keep most common germs at bay without the help of medications. This is true for both autologous (AUTO) and allogeneic (ALLO) transplant recipients.
However, a risk of serious infection remains for recipients of ALLO transplants beyond the first month. This risk occurs because ALLO transplant recipients are given anti-rejection drugs (medications that suppress the immune system to prevent the body from rejecting the donor's stem cells). The risk of infection increases when more anti-rejection drugs are needed.
Patients who have an ALLO transplant (which uses stem cells from another person) are at risk of developing a unique type of post-transplant illness called graft-versus-host disease (GVHD). It occurs when the transplanted stem cells recognize the patient's body as foreign and attack it, causing inflammation. GVHD ranges from mild to life-threatening. AUTO transplant recipients do not face this risk.
Fortunately, donor stem cells that are 100% matched to those of the patient rarely cause this problem, and doctors have medications that can prevent the development of GVHD; every patient receives these preventive anti-rejection medications. However, if the donor is less than a perfect match, or in rare cases when the match is 100%, GVHD can develop and make the patient ill. When this happens, the patient is given more anti-rejection medicines to treat the GVHD, but this increases the risk of infection.
GVHD is a double-edged sword, potentially helping or hurting the patient. At its worst, it can be fatal. However, in moderation, GVHD can be lifesaving because the transplanted cells have the ability to recognize and kill resistant cancer cells that may have escaped the chemotherapy and/or radiation treatment. Therefore, mild GVHD can ultimately lead to the cure of the patient. In fact, this is the primary way that ALLO transplantation cures cancers like leukemia.
There are two types of GVHD, both of which can occur with varying degrees of severity:
Acute GVHD (AGVHD). This form of the disease typically occurs within the first three months after an ALLO transplant, typically affecting the skin, intestines, and liver. Patients develop rashes, diarrhea, and jaundice (yellowing of the skin and the whites of the eyes) as each organ system is affected. Treatment consists of medications that block T cells (a type of white blood cell that helps the body's immune system fight infection).
Chronic GVHD (CGHVD). This form typically occurs more than three months after an ALLO transplant, and it can last a few months or a lifetime. It may be clinically "silent," producing no symptoms and requiring no specific therapy. Or it may become a source of medical problems needing regular medical attention and treatment. Symptoms may be mild (including dry eyes, dry mouth, and blood test abnormalities that indicate a slightly irritated liver) or more severe (including loss of skin elasticity, known as scleroderma; muscle and joint pains; weight loss; and difficulty breathing).
Doctors try to prevent severe GVHD from occurring. This is best accomplished by finding stem cells that best match those of the patient and by using preventive drugs during the first three to six months after the transplant.
Other common side effects
In addition to infection and GVHD, other side effects may occur during a transplant, often related to the destruction of the original bone marrow, the chemotherapy, or the radiation therapy. These include fatigue, mouth sores, sore throat, diarrhea, nausea and vomiting, low blood count, loss of hair, changes in skin pigmentation, rash, cataracts, sexual side effects, and infertility. The type, quantity, and severity of side effects often vary from patient to patient, depending on the patient's health, the amount of previous treatment, and the type of transplant received. These side effects can usually be managed through medication and go away over time.
Almost any part of the body has the potential to be affected in some way by the transplant process. Doctors will monitor a patient's recovery using a variety of tests, including those for the liver, kidneys, lungs, heart, and other organs. There is a risk of some permanent side effects from a bone marrow transplant, including infertility (the inability to have children) and cataracts (a clouding of the lens of the eye). Talk with your doctors about the possible short-term and long-term effects you may experience before having a bone marrow transplant, as compared with the risks and benefits of other available treatment options.
Last Updated: September 11, 2011