Hematologic Malignancies Program

Patient and Family Education

Myelodysplastic Syndromes (MDS)

Risk Factors

Although some cases of MDS are linked to known risk factors, most patients do not have any risk factors. At this time, the cause of the disease is still unknown. However, some risk factors include:

Age: One of the greatest risk factors may be age. Most MDS patients are elderly.

Smoking: The only suspected lifestyle-related risk factor for MDS is smoking. In addition to the lungs, mouth, throat and larynx, smoking can also affect cells that do not come into direct contact with smoke. Cancer-causing substances in tobacco smoke are absorbed into the blood that circulates through the lungs. Once in the bloodstream, these substances spread to many parts of the body.

Environmental exposures: Environmental risk factors, such as radiation and certain chemicals, have been linked to MDS. High-dose radiation exposure (such as surviving a nuclear reactor accident) increases the risk of developing MDS. Long-term workplace exposure to benzene and certain chemicals used in the petroleum and rubber industries can also increase your risk of developing MDS.

Cancer treatment: Patients with other cancers treated with certain chemotherapy drugs are more likely to develop MDS. The drugs most often associated (post-treatment) with MDS include:

mechlorethamine
procarbazine
chlorambucil
etoposide, teniposide
cyclophosphamide (to a lesser degree)

Combining these drugs with radiation therapy increases the risk further. Most of these cases of secondary MDS occur after treatment for Hodgkin's disease, non-Hodgkin's lymphoma or childhood acute lymphocytic leukemia.

Doctors are also seeing cases of MDS in patients who have had stem cell transplants (bone marrow transplants).

Congenital diseases: Fanconi anemia is a rare, inherited disorder associated with a greatly increased risk of developing leukemia or MDS as a child or young adult. These patients typically have shortages of one or more types of blood cells (white blood cells, red blood cells, and platelets) and may also have malfunctions of limbs and internal organs.

Sex: MDS is slightly more common in men.

This page was last updated on: October 7, 2009.