ConditionCancer
Myelodysplastic Syndromes (MDS)
Myelodysplastic syndromes (MDS) are a group of blood cancers in which the bone marrow makes abnormal, poorly working blood cells and too few healthy ones. This leads to low blood counts: anemia causing tiredness and breathlessness, low white cells causing infections, and low platelets causing bruising and bleeding. MDS mostly affects people over 65. Some forms progress slowly for years; others are more aggressive and can turn into acute myeloid leukemia. Treatment depends on the risk group.
Also called: MDS, myelodysplastic neoplasms, myelodysplasia, preleukemia (older term)
At a glance
- What it is
- A bone marrow cancer causing ineffective production of blood cells.
- Who gets it
- Mostly adults over 65; higher risk after chemotherapy or radiation, and with some inherited conditions.
- Symptoms
- Fatigue, breathlessness, pale skin, infections, easy bruising and bleeding; often found on a routine blood test.
- Diagnosis
- Blood count and smear, bone marrow biopsy with chromosome and gene tests.
- Risk groups
- Lower-risk (slow) and higher-risk (faster, more likely to become leukemia), using scores such as IPSS-R or IPSS-M.
- Treatment
- Transfusions and supportive care, growth factors, targeted medicines, hypomethylating drugs, stem cell transplant.
When to get help
Call 911 or go to the ER
- Fever of 38 °C (100.4 °F) or higher, chills or feeling very unwell, especially with a low white count: seek emergency care immediately
- Heavy bleeding, vomiting blood, black stools or a sudden severe headache
- Severe breathlessness, chest pain or fainting
See a doctor within a day or two
- Increasing tiredness, breathlessness or a racing heart, which may mean you need a transfusion
- Many new bruises, nosebleeds, bleeding gums or tiny red spots on the skin
- Frequent infections or mouth ulcers
Book a routine appointment
- A blood test showing low counts in one or more cell types, or large red cells without vitamin deficiency
- Unexplained, persistent tiredness in an older adult
- Previous chemotherapy or radiation, with new low blood counts
What happens in MDS
All blood cells come from stem cells in the bone marrow. In MDS, genetic changes in these stem cells cause them to produce abnormal (dysplastic) cells that often die before leaving the marrow. The marrow may be full of cells, yet the blood counts are low. Over time, some MDS cases accumulate more mutations and immature cells (blasts) increase. When blasts reach 20 percent or more, the disease is classified as acute myeloid leukemia. About 1 in 3 people with MDS eventually develop AML.
Causes and risk factors
- Age: most people are diagnosed after 65; the median age is about 70.
- Previous chemotherapy or radiation therapy ("therapy-related MDS"), often 5 to 10 years later.
- Chemical exposures: benzene, tobacco smoke.
- Inherited conditions: Fanconi anemia, dyskeratosis congenita, Shwachman-Diamond syndrome, GATA2 deficiency and others.
- Male sex.
- Clonal hematopoiesis: age-related blood cell mutations that slightly raise the risk.
In most people, no specific cause is found.
Symptoms
Many people have no symptoms at diagnosis. When present, symptoms come from low blood counts:
| Low count | Symptoms |
|---|---|
| Red cells (anemia) | Fatigue, weakness, breathlessness, pale skin, dizziness, fast heartbeat, chest pain |
| White cells (neutropenia) | Frequent or severe infections, fevers, mouth sores |
| Platelets (thrombocytopenia) | Easy bruising, nosebleeds, bleeding gums, tiny red spots (petechiae), heavy periods |
Diagnosis
- Complete blood count: low counts, often large red cells (high MCV).
- Blood smear showing abnormal cells.
- Excluding other causes: vitamin B12, folate, copper, thyroid, alcohol, medicines, HIV and other conditions.
- Bone marrow aspirate and biopsy: shows dysplasia and the percentage of blasts.
- Cytogenetics: chromosome changes, such as deletion of chromosome 5q (del(5q)), monosomy 7 or complex karyotype.
- Molecular testing: mutations such as SF3B1, TP53, ASXL1 and others that refine risk and guide treatment.
Risk scoring
The Revised International Prognostic Scoring System (IPSS-R) and newer molecular IPSS-M combine blast percentage, chromosome changes, blood counts and mutations to place people into risk groups from very low to very high. This guides treatment decisions.
Treatment
Lower-risk MDS
The goal is to improve blood counts and quality of life:
- Watch and wait if counts are stable and there are no symptoms.
- Red cell transfusions for anemia, with iron chelation if transfusion-related iron overload develops.
- Erythropoiesis-stimulating agents (such as epoetin or darbepoetin) to boost red cells.
- Luspatercept for some patients, especially with ring sideroblasts or SF3B1 mutations.
- Lenalidomide for MDS with del(5q).
- Imetelstat for some transfusion-dependent patients.
- Platelet transfusions and medicines for bleeding when needed.
- Immunosuppressive therapy in selected cases with hypoplastic MDS.
Higher-risk MDS
The goal is to delay progression to leukemia and extend life:
- Hypomethylating agents: azacitidine or decitabine (including an oral form), given in monthly cycles.
- Allogeneic stem cell transplant: the only potentially curative treatment, offered to fit patients, often after hypomethylating therapy.
- Clinical trials of newer combinations and targeted therapies.
Supportive care for all
- prompt treatment of infections; preventive antibiotics or antifungals in some cases
- vaccines (non-live) as recommended
- avoiding aspirin and NSAIDs when platelets are low
- managing fatigue and planning for treatment goals
Outlook
Survival varies widely by risk group: from many years in very low-risk disease to months in very high-risk disease without transplant. Newer treatments are improving outcomes, and some people live with lower-risk MDS for a decade or more with supportive care.
Frequently asked questions
Is myelodysplastic syndrome a type of cancer?
Yes. MDS is considered a type of blood cancer because it arises from abnormal, clonal bone marrow stem cells. Lower-risk MDS may progress slowly for years, while higher-risk MDS behaves more aggressively and can turn into acute myeloid leukemia.
What are the first symptoms of MDS?
The most common early symptom is tiredness from anemia, often with breathlessness on exertion and pale skin. Others include frequent infections, easy bruising, nosebleeds and tiny red spots on the skin. Many people are diagnosed after a routine blood test before symptoms appear.
What is the life expectancy with MDS?
It depends on the risk group. People with very low-risk MDS may live many years, often more than 8 to 10, while those with very high-risk MDS may live less than a year without effective treatment. Age, health and response to treatment also matter.
What is the difference between MDS and leukemia?
In MDS, the bone marrow makes abnormal cells but fewer than 20 percent are immature blasts. In acute myeloid leukemia, blasts make up 20 percent or more. MDS can progress to AML, which is why monitoring and, for higher-risk disease, treatment are important.
Can MDS be cured?
The only potential cure is an allogeneic stem cell transplant, which is suitable for some fitter patients. Other treatments, including hypomethylating drugs, targeted medicines and transfusions, control the disease, improve blood counts and quality of life, and can extend survival.
Sources
This guide was written from current patient and clinical guidance, including:
- National Cancer Institute: Myelodysplastic syndromes treatment (PDQ)
- American Cancer Society: Myelodysplastic syndromes
- National Comprehensive Cancer Network: Guidelines for patients, myelodysplastic syndromes
- Aplastic Anemia and MDS International Foundation: About MDS
- MedlinePlus: Myelodysplastic syndromes