Blood-forming cells in the body’s bone marrow can become abnormal. This can lead to low numbers of one or more types of blood cells. These abnormalities of the bone marrow, called myelodysplastic syndromes, are a type of cancer. There are six general types of MDS based on the type, characteristics, and/or a number of abnormal blood cells.
Normal bone marrow, found in the middle of certain bones in the body, is composed of blood-forming cells, fat cells, and supporting tissues. Healthy bone marrow produces immature blood cells, which develop into mature, functional red blood cells, white blood cells, and platelets.
These immature cell types in the bone marrow (red blood cells, white blood cells, or platelets) show dysplasia, an abnormality of the cells. They may accumulate in the bone marrow or have a shortened life span, resulting in fewer than normal mature blood cells in circulation. There may also be different types of cytopenia (low blood counts) of the different types of cells responsible for some symptoms, including infection, anemia, spontaneous bleeding, or easy bruising.
Different types of MDS are classified based on their appearance under a microscope, certain chromosomal changes, and other criteria.
Risk Factors
Risk factors include:
Age: MDS is most commonly diagnosed in the older population (over 65).
Medical History: Patients with previous cancer treatments (chemotherapy and radiation therapy) are at a higher risk.
Chemical Exposure: Long-term exposure to certain environmental or industrial chemicals, including tobacco smoke, pesticides, fertilizers, and solvents such as benzene, increase a person’s risk. Exposure to heavy metals like lead or mercury also causes a person to have an increased risk.
Smoking: (it is known that the risk of developing AML (a type of MDS) is 1.6 times greater for smokers than for non-smokers.)
Signs and symptoms for MDS vary depending on the type of blood cell that is affected
Red blood cells, the most common type of blood cell, carry oxygen from the lungs throughout the body and carbon dioxide back to the lungs. Having a low red blood cell count causes anemia, which depending on its severity, can have several symptoms, including:
Fatigue
Shortness of breath
Pale skin
Heart palpitations
Chest pain
White blood cells that guard the body against infection have different types of cells. The most common is the neutrophil. Having a low number of neutrophils in the blood is a condition called neutropenia which can lead to severe infections, including:
Skin infections
Nasal congestion/sinus infections
Lung infections, including cough/shortness of breath
Urinary tract infections
Fever
Platelets, a type of blood cell, help the blood clot. A low platelet count called thrombocytopenia can result in:
Abnormal bleeding, including nosebleeds and bleeding gums
Bruising
Diagnosis
Blood work includes a complete blood count (CBC), which measures the number of red and white blood cells and platelets.
A microscopic examination of the blood or bone marrow examines the different types of cells and the appearance of their cells to see if they are normal and healthy.
The pathologist will be particularly interested in determining what percentage of the cells are very early types of blood cells called blasts. With MDS, these blasts don’t develop properly. So for MDS to be confirmed, patients will have <20% of blasts.
Bone marrow biopsy and possible molecular testing of the bone marrow sample
Chromosome and/or DNA analysis of blood cells and bone marrow samples.
Treatment
Treatment for MDS varies based on symptoms, state of disease, and quality of life. All patients will continue to require routine bloodwork and monitoring of symptoms. Other treatments may include:
Supportive care such as antibiotics to treat infections, red blood cells, or platelet transfusions improves anemia and prevents bleeding.
Red blood cell stimulating growth factors
Chemotherapy
Stem cell transplant
Helpful Patient Resources:
We understand that receiving a cancer diagnosis can be a very scary and emotional time for patients and their families. Therefore. t is very important to discuss any questions or concerns you may have with your oncologist/hematologist. We highly recommend that if you do any research about your disease, you do so only with reputable sources. For your convenience, we’ve listed some below.