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A risk factor is anything that changes your chance of getting a disease such as cancer. Different cancers have different risk factors. Some risk factors, like smoking, you can change. Others, like your age or family history, can’t be changed.
But having a risk factor, or even several, does not always mean that a person will get the disease, and many people get cancer without having any known risk factors.
There are several known risk factors for myelodysplastic syndromes (MDS).
Older age is one of the most important risk factors for MDS. MDS is uncommon in people younger than 50, and most cases are found in people in their 70s or 80s.
MDS is more common in men than in women. The reason for this is not clear, although it might have to do with men having been more likely to smoke or to be exposed to certain chemicals in the workplace in the past.
Prior treatment with chemotherapy (chemo) is another important risk factor for MDS. Patients who have been treated with certain chemo drugs for cancer are more likely to develop MDS later on. When MDS is caused by cancer treatment it is called secondary MDS or treatment-related MDS.
Some of the drugs that can lead to MDS include:
The risk of secondary MDS varies based on the type and doses of drugs. It might also be affected by the type of cancer the chemo is treating. Combining these drugs with radiation therapy increases the risk further. People who have had stem cell transplants (bone marrow transplants) can also develop MDS because of the very high doses of chemo they received. Still, only a small percentage of people who are treated with these medicines will eventually develop MDS.
People with certain inherited syndromes are more likely to develop MDS. These syndromes are caused by abnormal (mutated) genes that have been passed on from one or both parents. Examples include:
In some families, MDS occurs more often than would be expected. Sometimes this is due to a known gene mutation that runs in the family, but in other cases the cause isn’t clear.
Smoking increases the risk of MDS. Many people know that smoking can cause cancer of the lungs, but it can also cause cancer in other parts of the body that don't come into direct contact with smoke. Cancer-causing substances in tobacco smoke are absorbed into the blood as it passes through the lungs. Once in the bloodstream, these substances spread to many parts of the body.
Some environmental exposures have been linked to MDS:
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
Aster JC, Stone RM. Clinical manifestations and diagnosis of the myelodysplastic syndromes. UpToDate. 2017. Accessed at https://www.uptodate.com/contents/clinical-manifestations-and-diagnosis-of-the-myelodysplastic-syndromes on October 4, 2017.
Howlader N, Noone AM, Krapcho M, et al, eds. SEER Cancer Statistics Review, 1975-2014, National Cancer Institute. Bethesda, MD, https://seer.cancer.gov/csr/1975_2014/, based on November 2016 SEER data submission, posted to the SEER web site, April 2017.
Komrokji RS, Padron E, List AF. Chapter 111: Myelodysplastic syndromes. In: DeVita VT, Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology. 10th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2015.
Steensma DP, Stone RM. Chapter 99: Myelodysplastic syndromes. In: Abeloff MD, Armitage JO, Niederhuber JE. Kastan MB, McKenna WG, eds. Abeloff’s Clinical Oncology. 5th ed. Philadelphia, Pa: Elsevier; 2014.
Last Revised: January 22, 2018
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