MDS - Myelodysplastic Syndromes
The information on this page can help you understand the nature of MDS but it is not a substitute for the advice of your doctor. Disease and treatment facts and statistics change over time and we cannot guarantee that all information is up-to-date and currently accurate. Always seek medical advice from a qualified physician.
Myelodysplastic Syndromes (MDS) are a group of related disorders in which stem cells in the bone marrow malfunction. Stem cells develop into red blood cells, white blood cells, and platelets. In MDS, defective stem cells produce too many defective blood cells and too few normal blood cells.
Defects in stem cells can cause blood cells to have an abnormal shape or size (dysplasia). The cells do not grow properly or live as long as normal blood cells. Defective cells can crowd out healthy cells in the bone marrow and leave the patient with too few mature cells in the blood. "Myeloid" means "related to bone marrow" so the name "myelodysplastic syndromes" indicates a set of diseases in which bone marrow cells are abnormally shaped, although misshapen cells are not the only sign of MDS.
MDS:
  • is a rare disease, although the exact number of affected patients is not known. In the U.S. there are approximately 15,000 new MDS cases each year (the disease incidence). There are estimated to be 50,000 to 100,000 people living with MDS in the U.S. (the disease prevalence).
  • is a clonal stem cell disease, meaning that when a defective stem cell clones itself (replicates) the new cells are also defective.
  • is not contagious. You cannot "catch" MDS from exposure to someone with the disease.
  • is not hereditary. You cannot inherit it from your parents or pass it on to your children. It is not known if people can have a genetic predisposition to bone marrow failure.
  • can appear at any age but is most commonly diagnosed in adults age 60 and older. The average age at diagnosis is 71 and 90% of MDS patients are over age 60.
  • affects more men than women.
  • is more common among Caucasians and less common among African-Americans, Asians, Inuits, Native Americans, and Pacific Islanders.
  • progresses to acute myeloid leukemia (AML) in 10-20% of patients.
  • can be treated in many ways but can be cured only with a bone marrow transplant or stem cell transplant.
Symptoms of MDS
The symptoms of MDS depend the types of blood cells that are affected and how low the patient's blood counts have fallen. Symptoms can vary widely from person to person, but nearly half of the people diagnosed with MDS have no symptoms at the time of diagnosis.
The most common symptom of MDS is feeling extremely tired or weak (fatigue) as a result of having a low red blood cell count. Red blood cells carry hemoglobin, an iron-rich protein that transports oxygen to the body. If you don't have enough hemoglobin-carrying red blood cells, your heart has to work harder to circulate the reduced amount of oxygen in your blood.
A low red blood cell count also can cause shortness of breath; rapid pulse; dizziness, especially when standing up; headache; coldness in your hands or feet; pale gums, nail beds, and skin (pallor); chest pain; decreased alertness; and shortened attention span.
White blood cells help fight infections. Symptoms of a low white blood cell count include fevers, frequent infections that can be severe, and flu-like illnesses that linger.
The cells called platelets stick together to seal cuts and stop bleeding. Symptoms of a low platelet count include the tendency to bruise and bleed easily and to have bleeding that may be hard to stop. Common types of bleeding include nosebleeds, bleeding gums, pinpoint red bleeding spots on the skin (petechiae), and blood in the stool. Women also may have heavy menstrual bleeding.
Because many of these symptoms can result from other conditions, a patient who experiences one or more symptoms of MDS does not necessarily have MDS. For the same reason, MDS may not be recognized or diagnosed at first if the person's blood counts are near normal. It is essential to consult a doctor for a professional diagnosis.
Causes and Risk Factors
While the exact causes of MDS is are not known, there are lifestyle factors and physical conditions that seem to be associated its development, including:
  • exposure to toxic chemicals, particularly benzene
  • smoking
  • treatment with high-dose radiation or chemotherapy for cancer
Secondary MDS refers to MDS resulting from cancer treatment and MDS caused by environment factors. MDS resulting from other causes is called de novo MDS. Secondary MDS can progress more rapidly and be more difficult to treat than de novo MDS.
The following can increase the risk of MDS:
  • exhaust gases
  • fertilizers
  • heavy metals
  • herbicides
  • ionizing radiation
  • marrow-damaging agents used in cancer chemotherapy
  • nitro-organic explosives
  • organic chemicals, including benzene, toluene, xylene, and chloramphenicol
  • pesticides
  • petroleum and diesel derivatives
  • stone and cereal dusts
  • tobacco smoke
Diagnosis of MDS
To diagnose MDS a doctor will review your medical history and symptoms and may ask you questions about exposure to toxic chemicals at home or work, whether you smoke, and if you have had chemotherapy or radiation treatments in the past.
A blood sample will be taken to measure levels of red cells, white cells, and platelets. The resulting report, called a Complete Blood Count (CBC), will be compared to normal blood counts to identify any counts that may be too low.
The doctor will also perform a pair of tests simultaneously: bone marrow aspiration (BMA) and bone marrow biopsy (BMB). The BMA provides information about the presence or absence of abnormal cells in the marrow. The BMB provides information about blood production in the marrow through the examination of the quantity (also knows as the cellularity) and quality of bone marrow cells.
For a patient to be diagnosed with MDS these two conditions must apply:
  1. At least one of the patient's blood counts must be abnormally low. This is called a cytopenia.
  2. The patient's bone marrow tests must show abnormal changes in the structure or form of the bone marrow. This is called dysplasia.
These bone marrow tests are also important for determining the number of blast cells in the bone marrow. Blasts are immature white blood cells that are normally less than 5% of bone marrow cells. In MDS, blasts may occur in higher numbers and may also be found in circulating (peripheral) blood. Doctors measure the percentage of blasts in the bone marrow and in the bloodstream because these are key indicators (see "Classification of MDS" below). The doctors will also look for abnormalities in your chromosomes and check for the presence of granules called Auer rods.
When MDS is present, the bone marrow is likely to be hypercellular, or full of cells. In about 5% to 10% of patients the bone marrow is hypocellular, or lacking in cells. It can be difficult to distinguish between hypocellular MDS and aplastic anemia because doctors can't always get adequate samples of marrow cells from a bone marrow aspiration.
The Mechanism of MDS
In the human body, stem cells in the bone marrow reproduce (clone) themselves to produce a population of stem cells. Stem cells mature into:
  • red blood cells (erythrocytes). They carry hemoglobin, an iron-rich protein that transports oxygen to the body.
  • platelets (thrombocytes). They help blood clot.
  • white blood cells (leukocytes). As part of your immune system they destroy "bad" cells: invading or foreign cells like bacteria and viruses, and abnormal cells.
In healthy people these cells enter the circulating blood as they become mature. In a person with MDS, some of these cells do not mature and may collect in the bone marrow or bloodstream in immature form:
  • reticulocytes: red blood cell precursors
  • myelocytes: white blood cell precursors
  • megakaryocytes: platelet precursors
The low blood counts and resulting symptoms experienced by MDS patients result from the lack of one, two, or three lines of mature cells:
  • anemia: insufficient red blood cells
  • neutropenia: insufficient white blood cells
  • thrombocytopenia: insufficient platelets
Classification of MDS


Use the Marrowforums
MDS Classification Tool
to identify your IPSS score, IPSS classification, WHO subtype, and MDS subtype.
There are three systems for classifying MDS severity and MDS subtypes (more specific subsets of the range of MDS syndromes):
  1. IPSS Scores
  2. WHO Classification
  3. FAB Classification
These classification systems help doctors determine the types of medications or treatments that might work best, how the disease is likely to progress over time, and how long you may live. When you look at statistics about treatments and clinical trials, or read medical research documents, patients will often be categorized by one of these classifications. Some treatment centers use slightly different criteria than those shown below, producing slightly different definitions of each MDS subtype.
IPSS Scores
The International Prognostic Scoring System (IPSS) assigns patients a score based on these factors: changes in cytogenetics (DNA changes in the bone marrow), blood counts, and blasts (immature white blood cells in the bone marrow). Each factor gets a score. The total score across all factors determines the patient's risk group.
First, add up your score using the IPSS Point Chart. Then look up your total in the IPSS Classification Chart.
IPSS Point Chart
Factor Value IPSS Score
Blasts in bone marrowless than 5%0
5% to 10%0.5
11% to 20%1.5
21% to 30% (acute myelogenous leukemia)2.0
Cell DNA changes (cytogenetics) Good: any of the following:
* normal set of 23 chromosomes
* partial loss of chromosome 5 only
* partial loss of chromosome 20 only
* loss of the Y chromosome only
0
Intermediate: anything other than "good" or "poor" 0.5
Poor: any of the following:
* loss of one of the two 7 chromosomes (monosomy 7)
* addition of a third 8 chromosome (trisomy 8)
* three or more total abnormalities
1.0
Low Blood Counts (cytopenias) 2 or 3 of the following cytopenias:
* hemoglobin (HGB) < 10%
* white blood cell (WBC) count < 1,800 per microliter (ÁL)
* platelets < 100,000 per microliter (ÁL)
0.5
IPSS Classification Chart
IPSS Score IPSS Classification
0Low-risk
0.5Intermediate-1
1.0
1.5Intermediate-2
2.0
2.5High-Risk
3.0
3.5
WHO Classification System
The World Health Organization (WHO) classification system divides MDS into eight subtypes based on tests of the blood and bone marrows.
MDS Subtype Blood Findings Bone Marrow Findings
RA (Refractory Anemia)

RA and RARS are considered the mildest subtypes. MDS is limited to red blood cells. There is little dysplasia.
Low red blood cell count

Few or no blasts
Dysplasia (abnormal shape or size) in only 1 type of blood cell: the red blood cell precursors

Less than 5% blasts

Less than 15% red blood cells contain ringed sideroblasts (ring-shaped iron deposits)
RARS (Refractory Anemia with Ringed Sideroblasts)

RA and RARS are considered the mildest subtypes. MDS is limited to red blood cells. There is little dysplasia.
Low red blood cell count

Few or no blasts
Dysplasia in only 1 type of blood cell: red blood cell precursors

Less than 5% blasts

15% or more ringed sideroblasts
RCMD (Refractory Cytopenia with Multilineage Dysplasia) At least 2 of the following:
• low red blood cell count
• low white blood cell count
• low platelet count

Few or no blasts

No Auer rods

Monocytes less than 1 x 109/L
Dysplasia in 2 or more cell types, affecting at least 10% of the cells

Less than 5% blasts

No Auer rods
RAEB-1 (Refractory Anemia with Excess Blasts 1) At least 1 of the following:
• low red blood cell count
• low white blood cell count
• low platelet count

Less than 5% blasts

No Auer rods

Monocytes less than 1 x 109/L
Dysplasia in 1 or more cell types

5% to 9% blasts

No Auer rods
RAEB-2 (Refractory Anemia with Excess Blasts 2) At least 1 of the following:
• low red blood cell count
• low white blood cell count
• low platelet count

5% to 19% blasts

Auer rods

Monocytes less than 1 x 109/L
Dysplasia in 1 or more cell types

10% to 19% blasts

Auer rods
MDS Del(5q) (MDS with the 5q- syndrome, also called Deletion 5q)

More common in women age 65 and older who have mild to moderate degrees of anemia and a low white blood cell count.
Low red blood cell count

Normal or high platelet count

Less than 5% blasts
Dysplasia in platelet precursors with hypolobated nuclei

Less than 5% blasts

No Auer rods

Deletion of chromosome 5q

No other chromosome abnormalities
MDS-U (Unclassified MDS)

1% to 2% of MDS patients
At least 1 of the following:
• low red blood cell count
• low white blood cell count
• low platelet count

Few or no blasts

No Auer rods
No dysplasia in red blood cell precursors

Dysplasia in exactly 1 of the following:
• white blood cell precursors
• platelet precursors

Less than 5% blasts

No Auer rods
AML (acute myelogenous leukemia)

Not considered MDS
At least 2 of the following:
• low red blood cell count
• low white blood cell count
• low platelet count

5% or more blasts
Dysplasia in white blood cell precursors

20% or more blasts
FAB Classification
The FAB classification system was developed in the 1970s by a group of French, American, and British pathologists. Based on the percentages of blast cells in the bone marrow and in the peripheral (circulating) blood, the FAB classification has been largely superseded by the IPSS and WHO systems, but is still found in medical literature.
MDS Subtype Blood Findings Bone Marrow Findings
RA (Refractory Anemia) Less than 1% blasts Dysplasia in 1 or more cell types

Less than 5% blasts

Less than 15% ringed sideroblasts
RARS (Refractory Anemia with Ringed Sideroblasts) Less than 1% blasts Dysplasia in 1 or more cell types

Less than 5% blasts

15% or more ringed sideroblasts
RAEB (Refractory Anemia with Excess Blasts) 2 or more cytopenias

Less than 5% blasts
Dysplasia in 1 or more cell types

5% to 20% blasts
RAEB-t (Refractory Anemia with Excess Blasts in Transformation) 2 or more cytopenias Dysplasia in 1 or more cell types
5% or more blasts in circulating blood
OR
21% to 30% blasts in bone marrow
CMML (Chronic Myelomonocytic Leukemia) Less than 5% blasts

Monocytes of 1 x 109/L or more
Dysplasia in 1 or more cell types

5%-20% blasts
AML (Acute Myeloid Leukemia)   Dysplasia in white blood cells

30% or more blasts
Treatment of MDS
The choice of treatment for MDS depends on a variety of factors, including:
  • severity of symptoms
  • age
  • IPSS score and subtype of MDS (see "Classification of MDS" above)
  • presence of other serious medical conditions or diseases
  • availability of a matched donor for bone marrow or stem cell transplant
There are many approaches to treatment of MDS. The more you learn about the choices, the better you will be able to be a partner with your doctor in making treatment decisions. In milder cases doctors may recommend only regular tests to watch for changes. This may be all that is needed in the early stages of MDS or even later if the disease remains very low-risk. But MDS can be life-threatening and in severe cases require immediate hospitalization.
Many patients live basically normal lives for decades with MDS. Survival times vary greatly and depend on the individual circumstances for each patient. When you read statistics about MDS remember that statistics are only indicators, not guarantees or predictions. All patients react to their illness and treatment differently.
MDS cannot be corrected through dietary changes or supplements because patients do not have healthy bone marrow capable of producing properly functioning blood cells. However, a good diet is always important. Doctors may recommend dietary changes and supplements to lessen symptoms that result from MDS. Talk to your doctor before taking any supplement, including herbal supplements.
Current treatment options include:
  • watch and wait — supportive care
  • blood or platelets transfusions
  • growth factors
  • drugs for immunosuppression
  • drugs for MDS
  • bone marrow, stem cell, and cord blood transplants
Watch and Wait — Supportive Care
If you have only mild/tolerable symptoms, your doctor may recommend a watch and wait strategy or supportive care to manage or lessen symptoms rather than try to slow or stop the course of the disease itself. Monitoring your symptoms, performing tests on a regular basis, and giving you transfusions, antibiotics, and other treatment only as needed may be sufficient in the early stages of MDS or even later if the disease remains very low-risk. Watch and wait is a conscious decision to avoid making things worse when you are living a mostly normal life.
Transfusions
Transfusions replace blood cells when your counts are low. Red (whole) blood transfusions boost your red blood cell count. Platelet transfusions boost a low platelet count. Exactly how low is "too low" is individual, since some patients are better able than others to live with low counts, and there's a balance between the risks of low counts and the risks of frequent transfusions. Doctors also vary in their recommendations of thresholds under which transfusions should be given.
Frequent whole blood transfusions can lead to iron overload because whole blood comes with iron that your body stores. Iron buildup from long-term treatment with transfusions can damage key organs such as the heart and liver. Iron can be removed with drugs called chelators (trade names Desferal and Exjade) but they can be difficult to administer and hard to tolerate.
Because MDS patients may receive many transfusions, it is recommended that they receive blood that is filtered and irradiated. Filtering removes leukocytes that might otherwise cause allergic reactions. Irradiating inactivates lymphocytes to avoid a buildup of antibodies that could prevent future transfusions from being effective. Filtered blood is also called leukocyte-reduced or leukocyte-depleted. Many patients also believe that patients who receive frequent transfusions should receive fresh (very recently donated) blood because it might sustain them longer; this topic is a subject of debate.
Growth Factors
The proteins or hormones called growth factors are normal body products that stimulate the production of blood cells.
  • Erythropoietin ("EPO" for short, trade names Aranesp, Epogen, and Procit) is a growth factor that boostsless red blood cell production.
  • G-CSF (granulocyte colony-stimulating factor) like filgrastim (trade names include Neupogen) can boost white blood cell counts.
  • GM-CSF (granulocyte macrophage colony-stimulating factor) like sargramostim (trade names include Leukine) can also boost white blood cell counts.
Drugs for Immunosuppression
MDS patients may be treated with antithymocyte globulin (ATG) or antilymphocyte globulin (ALG), in combination with cyclosporine. These immunosuppressive drugs keep the patient's own immune system from attacking the bone marrow, allowing the bone marrow to begin making healthy blood cells again. They are typically used for lower-risk patients. (Note: ATG/ALG+cyclosporine is a front-line treatment for aplastic anemia.)
Drugs for MDS
These MDS drugs have been developed in the last decade. The tradeoffs among them as well as ideal treatment schedules are continuing areas of research.
  • Lenalidomide (trade name Revlimid) is an anti-angiogenic agent that works by slowing the growth of the blood vessels that feed MDS cells, and killing abnormal cells. Approved for lower-risk, transfusion-dependent MDS patients with the "5q-" abnormality of chromosome 5.
  • 5-azacitidine (trade name Vidaza) and Decitabine (trade name Dacogen) are demethylating agents prevent the growth of abnormal bone marrow cells. Approved for all MDS subtypes.
These chemotherapy drugs are used only for the highest-risk MDS patients:
  • Cytarabine (trade name Ara-C) and Hydroxyurea (trade name Hydrea) are low-dose chemotherapy drugs target abnormal stem cells and are typically used for higher-risk MDS patients who are transforming or are at increased risk of transforming to acute myelogenous leukemia (AML).
  • Daunorubicin (trade name Cerubindine), Idarubicin (trade name Idamycin), and Mitoxantrone (trade name Novantrone) are high-dose chemotherapy drugs used to treat high-risk MDS patients.
Bone Marrow, Stem Cell, and Cord Blood Transplants
Currently, the only option for curing MDS is an allogeneic transplant using bone marrow, stem cells, or cord blood. "Allogeneic" means that the cells come from someone other than the patient. The patient receives bone marrow or stem cells from a family member, unrelated donor or cord blood unit. In a successful transplant, defective stem cells in the patient's bone marrow are eliminated and new cells from the donor engraft (begin to function in the recipient's marrow) and produce normal blood cells.
The major risks are rejection of the transplant, mortality during the transplant process (while waiting for engraftment the patient may have no immune system), and graft-versus-host disease (GVHD or GVH). GVHD is an acute or chronic condition in which the patient's new immune system tries to reject his or her own tissue.
Standard transplants begin with chemotherapy and radiation to destroy diseased cells, while mini transplants (non-myeloablative transplants) use lesser or no chemotherapy or radiation, making them more suitable for older patients or those with other health problems for whom the standard transplant conditioning would be unsuitable. Mini transplants may shorten recovery time but have higher relapse rates, or change the balance of risks and benefits in other ways.
To increase the likelihood of a successful transplant and minimize potential complications, the patient needs a donor with a matching tissue type. Human leukocyte antigen (HLA) typing, which looks at proteins on the surface of cells, is used to match patients and donors. This is not the same as testing your blood type; donors don't have to match your blood type.
Many patients find HLA matches among their brothers, sisters, or other close relatives (an identical twin sibling is the ideal donor), but as many as 70% of patients must search for an unrelated donor or cord blood unit. Doctors can search for donors on behalf of their patients in the Be The Match Registry operated by the National Marrow Donor Program (NMDP). A MUD transplant is one from a "matched unrelated donor."
Transplants involving partially matched (called "mismatched") donors are also possible, depending on the type of mismatch, but such transplants are riskier.
Because it can take time to identify a donor, it is a good idea to explore the possibilities in the patient's family and/or bone marrow registries as soon as MDS is diagnosed.
Clinical Trials
A clinical trial is a study conducted to evaluate a promising new treatment or to continue to learn about a current successful treatment.
Each study is designed to answer scientific questions and to find new and better ways to help patients. Clinical trials are important because the research data they provide is the route to safer and more effective treatments for all patients.
Clinical trials involve some risk because the treatments are less proven than standard treatments. However, they offer some of the best medical care available, provide both the latest and best medical expertise, and patients receive close attention and monitoring. In addition, trials offer consistency in treatment protocols and quality controls that might vary in other settings.
Usually, clinical trials are free-of-charge for the patient, with some facilities even financing travel expenses. Most insurance companies cover treatment received in clinical trials. Patients should consider participating in a clinical trial only after their doctor has explained the trial's specific purposes, risks, and potential benefits.
To learn more about clinical trials for MDS in the U.S., visit ClinicalTrials.gov or call 888-346-3656. Other excellent resources for information about clinical trials include:
Coping with MDS
Following a diagnosis of MDS, patients may feel shocked, scared, angry, or even relieved that they finally have a "name" for their condition. Newly diagnosed patients often describe being overwhelmed by trying to understand what MDS is, what the various subtypes mean, and how their MDS can be treated while their family and work responsibilities continue. MDS is a complicated disease and trying to make sense of the benefits and risks of each possible treatment can add to a patient's burden.
As a rare disease, MDS may be unfamiliar to your general practitioner and you are unlikely to know someone else who has the disease.
Here are some steps that will help you feel more in control of your situation:
  • Find a hematologist who is an expert in treating MDS. Get a referral from your primary care physician or insurance company. You can also use the Marrowforums Treatment Center Map to find treatment centers in North America.
  • Request information from the Aplastic Anemia & MDS International Foundation (AA&MDSIF). Visit their Online Learning Center. Attend their conferences. If you'd like to talk to another patient or caregiver, ask to speak to one of their Peer Support Network volunteers.
  • Read the Patient Handbook offered by the MDS Foundation.
  • Contact national patient or support organizations in your country, such as the Aplastic Anemia & Myelodysplasia Association of Canada and the MDS UK Patient Support Group.
  • Learn as much as you can about MDS and its treatments. Learning the basic terminology of MDS will help you understand what you read and communicate with your doctor.
  • Keep track of all of your medical information, including symptoms, tests and their results, treatments (including transfusions received), an up-to-date list of your medications, and contact phone numbers, in one place. A computer, a three-ring binder, or even a folder of papers will work; just keep everything together.
  • Be an active participant in your care by asking questions of your doctors until you understand the answers, discussing information you collect, and speaking up about anything that concerns you. Bring a written list of questions to each appointment.
  • If possible, have a family member or close friend accompany you to medical appointments. They can help you listen, take notes, and make sure you remember to ask your questions.
  • Get a second opinion. No reputable doctor will object to your confirming your diagnosis and treatment recommendations with another specialist.
  • Take advantage of services offered at your treatment center (counselors and social workers, language translators, etc.), wellness programs of your insurance company, and support offered by religious groups, even if these services aren't specific to bone marrow failure diseases.
  • Join support groups in your city. You can find them through your treatment center, among the AA&MDSIF Communities of Hope, among the MDS Foundation Support Groups), or in the Marrowforums Suupport Groups forum.
  • Keep in regular touch with family, friends, and the others closest to you. Don't let relationships falter just because your situation has changed.
  • Talk to other patients in the Marrowforums discussion forums.
  • Keep up with news and reports at MDS-related websites such as the MDS Foundation and The MDS Beacon.
  • Visit sites with MDS-specific discussion areas such as the MDS section of Talk Blood Cancer Australia and the MDS Foundation forums.
We hope that after reading this page you will participate in the discussions at Marrowforums and continue to learn about MDS through the experiences of patients, family members, and caregivers who exchange help and support 24 hours a day, every day of the year.