Myelodysplastic syndromes (MDS)

Síndromes mielodisplàsiques a Vall d'Hebron

They are a heterogeneous group of blood stem cell cancers characterised by altered haematopoiesis (production of blood elements), which results in normal or hypercellular bone marrow, but due to a high rate of death in blood cells in the bone marrow, peripheral blood cells are scarce (cytopaenia) and morphologically abnormal (dysplasia).

Clinical progression in patients with MDS varies and they may be at increased risk of developing acute leukaemia, depending on the subtype of MDS.

They may appear de novo or secondary to cytotoxic treatments or radiotherapy.

Description

Patients with MDS often show no symptoms and diagnosis occurs as a result of analytical testing. When symptoms do appear, however, they are most often secondary to cytopaenia. The most common are weakness, paleness, palpitations or feeling short of breath with exertion due to decreased haemoglobin (anaemia). Sometimes, infections may appear as a result of lack of white blood cells (neutropaenia) or bleeding due to the low number of platelets (thrombocytopaenia). These symptoms are not specific to the condition and therefore those with persistent appearance of these symptoms should consult their GP.

How is affected?

MDS are not common conditions. 3-4 new cases are detected each year for every 100,000 people. They are more common in patients over 65 years old (75 cases/100,000 people) and they are twice as common in men as in women.

Diagnosis

The diagnostic process begins with an analysis to look for cytopaenia. Once other causes that may justify cytopaenia are ruled out, a bone marrow exam is conducted using bone marrow aspiration (this is the organ responsible for producing the blood elements).

Bone marrow aspiration consists of a puncture in the breastbone or in one of the pelvic bones, performed with a fine needle under local anaesthesia. 4-10 ml of bone marrow is extracted through aspiration. In rare cases, it is necessary to remove a bone core by puncture biopsy with a thick needle (Tru-cut). Sometimes, the test needs to be repeated after some time to confirm the diagnosis.

Typical treatments

Treatment will depend on the biological characteristics of the condition and the patient’s general state of health.

It is based on:

1. Support treatment through blood transfusions.

2. Treatment using drugs that aim to restore correct bone marrow function.

3. Bone marrow transplant. Replacing the bone marrow of the person affected with that of a healthy person who is immunologically compatible. This option is very aggressive and can therefore only be offered to a certain group of young patients in good physical health and affected by a specific group of MDS.

4. Clinical trials. Studies that use new drugs with proven efficacy in this group of conditions.