Myelodysplastic syndromes (MDS) are bone marrow malignant diseases resulting in ineffective haematopoiesis and subsequently, blood cell count decrease. Patients have anaemia responsible of fatigue and high heart frequency, thrombocytopenia responsible of increased risk of bleeding and neutropenia responsible of increased risk of infection. The patients suffering from MDS also are at increased risk of developing acute myeloblastic leukemia (AML). Allogeneic stem cell transplantation (alloSCT) remains the only curative option for patients with aggressive MDS. However, these patients are frequently ineligible for this kind of treatment, because of, for instance, age and co-morbidities. Thus, other treatment options are needed and Azacytidine (AZA), a hypomethylating agent is then proposed. With this COMYRE observatory study, we wanted to analyse which patients undergo alloSCT, why they are not eligible to alloSCT if it is the case, the overall survival of all the patients and if there are some factors which can influence this survival. It could help us to better identify the best candidate for alloSCT and those for other treatments such as AZA.

Myelodysplastic syndromes (MDS) are a heterogeneous group of myeloid disorders due to qualitative defects of the hematopoietic stem cell, resulting in uneffective hematopoiesis, dysplasia of one or more lineages, and subsequently, various cytopenias. The patients suffering from MDS are at increased risk of developing acute myeloblastic leukemia (AML). Allogeneic stem cell transplantation (alloSCT) remains the only curative option for patients with intermediate-2 or high risk MDS according to International Prognostic Scoring System (IPSS). However, since these patients are frequently ineligible for this kind of treatment, because of age and co-morbidities, other treatment options were needed. Thank to AZA-001 trial results, Azacytidine (AZA), a hypomethylating agent is validated in Europe for the treatment of MDS patients who are not candidate for alloSCT. In most of cases, AZA is a well-tolerated drug comparing to more classical chemotherapy or alloSCT. Indeed, the most frequent reported side effects are fatigue, constipation, joints and muscle pains, cytopenias and these side effects rarely have significant clinical consequences. On the contrary, during alloSCT procedure, we could observe more infectious events, graft versus host disease, more toxicity.

In this COMYRE observatory study, all high risk MDS with age below 70 are included. The aim of the study is to analyse which patients undergo alloSCT and why they are not eligible to alloSCT if it is the case. We also want to analyse the overall survival of all included patients and we will try to identify if there are some factors which can influence this survival. Thus, it could help us to better identify the best candidate for alloSCT and those for other treatments such as AZA, regarding the benefit/toxicity.

Inclusion Criteria:

• Age> 18 years old and <70 years old
• MDS-HR defined by an intermediate or high IPSS score (≥ 1.5), or IPSS revised ≥ to 4.5.
• Diagnosis affirmed by 2 myelograms at least 1 month apart or 1 single characteristic myelogram if prior haematological abnormalities on complete blood count present for more than 6 months
• Free informed consent signed by the patient and the investigator (at the latest on the day of inclusion and before any examination required by the study)
• Affiliate or beneficiary of a social security system

Exclusion Criteria:

• Age ≥ 70 years
• MDS-LR defined by a low IPSS score (<1.5), or revised IPSS <4.5
• Women of childbearing potential not using contraception, pregnant or breastfeeding
• Not affiliated to the Social Security system

Patients with MDS-HR defined by an intermediate or high IPSS score (≥ 1.5), or IPSS revised ≥ to 4.5