What is Myelodysplastic Syndrome (MDS)?

What is Myelodysplastic Syndrome (MDS)?

Myelodysplastic syndromes (MDS) are a group of blood cancers resulting from abnormal blood cells in the bone marrow. With myelodysplastic syndrome, early blood cells in the bone marrow do not mature and fail to become healthy blood cells.

Myelodysplastic syndromes can cause several forms of serious health conditions. Treatment for MDS typically focuses on managing symptoms, slowing its progress, and addressing the conditions that stem from the disease.

Diagram of cross section of bone to illustrate how MDS mutates and multiplies abnormal plasma cells and antibodies

Types of MDS


In the United States, around 15,000 to 20,000 people are diagnosed with myelodysplastic syndromes each year. Myelodysplastic syndromes (MDS) are often classified into specific subtypes. The classification can be based on the characteristics of the abnormal cells, including:

  • Chromosome and genetic changes in the affected blood cells
  • Blood count levels, including a low red cell blood count, indicate anemia
  • Percentage of immature “blast” cells. Immature (blast) cells remain clustered in the bone marrow
  • Percentage of sideroblasts. Sideroblasts are named for the iron-laden ring around the cell’s nucleus. The presence of abnormal sideroblasts causes high amounts of iron to become trapped in developing red blood cells.

Types of MDS subtypes include:

  • Refractory Anemia (RA)
  • Refractory anemia with ringed sideroblasts (RARS)
  • Refractory cytopenia with multilineage dysplasia (RCMD)
  • Refractory cytopenia with multilineage dysplasia and ringed sideroblasts (RCMD-RS)
  • Refractory anemia with excess blasts (RAEB)
  • Myelodysplastic syndrome, unclassified (MDS-U)
  • MDS associated with isolated del (5q)

Symptoms & Signs of MDS


Symptoms of myelodysplastic syndrome will vary from case to case depending on the subtype of MDS. Some people may not immediately experience signs of myelodysplastic syndrome but develop symptoms over time.

Symptoms of MDS may include:

  • Fatigue
  • Shortness of breath
  • Anemia
  • Frequent infections due to a low white blood cell count
  • Easy bruising due to a low blood platelet count
  • Unusual bleeding due to a low blood platelet count
  • Pale appearance (pallor) due to a low red blood cell count (anemia)
  • Petechiae are round, pinpoint-size spots that appear in clusters or as a rash on the skin due to bleeding

If your doctor suspects you have myelodysplastic syndrome, they may refer you to a hematologist (blood disorder specialist) for further diagnosis and treatment options.


What Causes MDS?


Myelodysplastic syndrome begins in the bone marrow. Bone marrow is a spongy tissue found in the center of most bones. It produces billions of new, immature blood stem cells, which can mature into red blood cells (to carry oxygen), white blood cells (to fight infection), and platelets (to stop bleeding).

With myelodysplastic syndromes, some immature blood cells never mature. Over time, this can lead to a depletion of healthy red and white blood cells and platelets. The body will have more defective cells than healthy ones.

Risk Factors

Risk Factors

There is no known reason why some people are at risk of developing myelodysplastic syndromes. However, some MDS risk factors have been linked to:



Complications that may arise from myelodysplastic syndromes mirror the signs and symptoms of the condition and depend on the subtype of MDS.

Complications of MDS include:

  • Recurring infections
  • Anemia
  • Excess bleeding
  • Risk of cancer, including acute myeloid leukemia (AML)
Get Care

Trust NewYork-Presbyterian for MDS Care

NewYork-Presbyterian doctors and blood cancer care specialists are well-versed in recognizing the signs and symptoms of myelodysplastic syndrome and can offer expert and compassionate treatment options.

For the best treatment solutions for myelodysplastic syndromes, contact NewYork-Presbyterian for an appointment.