What are myelodysplastic syndromes?

Myelodysplastic syndromes (MDS) are diseases of the blood cells. Some myelodysplastic syndromes have only a mild to moderate impact on a person's life and are not progressive. Myelodysplastic leukemia, however, is a slowly developing blood cell-related cancer that is usually terminal. MDS occurs when the blood-forming cells in the bone marrow produce cells that do not mature properly, leading to low counts of healthy red blood cells, white blood cells, and platelets in the blood. Myelodysplastic syndromes may be manifest in different degrees of severity, from mild anemia to acute myelogenous leukemia. MDS most often affects people over the age of fifty.

What is aplastic anemia?

Aplastic anemia occurs when the bone marrow's blood-forming cells stop producing new blood cells. The decrease in red blood cell production means that too few red blood cells are present in the blood stream-a condition known as anemia. Red blood cells are responsible for delivering oxygen to the body's tissues, so severe anemia can be very serious. In addition, aplastic anemia results in lowered immune system defense due to a decrease in the number of white blood cells and a tendency for excessive bleeding because of the lowered number of platelets.

The main difference between MDS and aplastic anemia is that in MDS, the bone marrow produces abnormal or immature blood cells that do not function properly, whereas in aplastic anemia the marrow stops producing new blood cells entirely. In addition, MDS is more common among older people, while aplastic anemia often affects the young.

What is secondary aplastic anemia?

Secondary aplastic anemia is the name given to aplastic anemia when the damage to the bone marrow is caused by:

• Chemotherapy
• Radiation
• Cancer medications
• Pregnancy
• Exposure to chemicals such as benzene - if you have transported benzene, gasoline, or worked in the petrolium or petro-chemical industries, click here to learn your legal rights

What are the symptoms of myelodysplastic syndromes?

The symptoms of anemia and MDS are often similar. Symptoms of anemia include fatigue, shortness of breath, general weakness, and pale skin. These symptoms may also indicate myelogenous leukemia, other symptoms of which include weight loss, mild depression, and loss of appetite. Because the symptoms associated with aplastic anemia and MDS may also be indicative of other health problems, only an oncologist or other qualified doctor can make an accurate diagnosis.

What are the causes of myelodysplastic syndromes?

The use of DNA-damaging drugs, exposure to radiation, and contact with benzene are all possible causes of MDS, aplastic anemia, and acute myelogenous leukemia. DNA-damaging drugs include those used to treat breast, ovarian, or other types of cancer. Radiation exposure may occur during treatment for lymphoma. The people most likely to come into contact with benzene are those who work in industrial settings. Although benzene is more strictly regulated now than before its cancer-causing properties were known, exposure to benzene still accounts for some new cases of MDS, aplastic anemia, and leukemia.

What are the treatments for myelodysplastic syndromes?

Treatments for myelodysplastic syndromes vary according to the severity of a person's MDS. People with mild cases may not require treatment. Those with low blood cell counts may be helped by medications, platelet or red blood cell transfusions, or bone marrow transplants. Chemotherapy and biological therapy treatments are under study for use in serious cases. In the rare case that the patient is under age fifty, an aggressive course of treatment using chemotherapy, radiation, and stem cell transplantation may be considered.

The most successful treatment for aplastic anemia is bone marrow transplantation. This procedure is most likely to be effective when a related donor with marrow similar to the patient's (matched marrow) is available. Unrelated or unmatched donors succeed in some cases as well. Immunosuppressive drug therapy may also be helpful, but increases the patient's risk of developing leukemia later on. Other types of treatments, such as blood transfusions, peripheral stem cell transplants, and clinical trials, may also be available.

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