Search

Refractory anemia, also known as myelodysplastic syndromes, forms a group of clonal diseases characterized by cytopenias with mostly rich bone marrow. Preferentially reaching an older population, the prognosis depends on both comorbidities and characteristics of the disease, which have been grouped into a score established in 1997 ("IPSS = International Prognostic Scoring System") and revised in 2012 ("R-IPSS = Revised IPSS"). Overall survival and risk of transformation into acute nonlymphoblastic leukemia can now be estimated fairly accurately. Based on these characteristics, the treatment will be mainly supportive or will use several new molecules: growth factors, lenalidomide, 5-azacitidine, etc. A minority of patients may also benefit from allogeneic BMT or sometimes immunosuppressive therapy.

Myelodysplastic syndromes (MDS) are myeloid disorders with various clinical and biological presentations. The French-American-British (FAB-1982) classification included five categories basing on morphology and bone marrow blast count. Three criteria are taken into account: 1) the percentage of blasts in peripheral blood and bone marrow, 2) the percentage of ringed sideroblasts, and 3) the number of monocytes in peripheral blood. The World Health Organization classification (WHO 2001, 2008) modifies the FAB system by also taking cytogenetic characteristics and molecular biology into consideration. The last classification (WHO-2008) takes into account: 1) the number of peripheral cytopenia, 2) the percentage of blasts in peripheral blood and bone marrow, 3) the percentage of ringed sideroblasts, 4) the possible presence of Auer Rods, and 5) the detection of a cytogenetic abnormality (the isolated 5q deletion). The following subgroups are defined: refractory cytopenia with unilineage dysplasia, refractory anemia with ringed sideroblasts, refractory cytopenia with multilineage dysplasia, refractory anemia with excess blasts, myelodysplastic syndrome unclassifiable and myelodysplastic syndrome with isolated del(5q).

Myelodysplastic syndromes are relatively frequent, with a distinct predominance in elderly subjects. They are characterized by a disorder of myeloid precursor cell maturation, which explains the presence of blood cytopenia responsible for clinical manifestations (anaemia, infection, haemorrhage). Beside cytopenia, the main risk is transformation into acute myeloid leukaemia. As a rule, these diseases are easily recognized by the conjunction of blood count and bone marrow aspirate. Apart from the intensive therapy prescribed for myelodysplastic syndromes in young subjects, treatments seldom have beneficial effects and are still symptomatic in most cases.

The myelodysplastic syndromes are a group of hematological disorders not yet clearly defined. The authors describe the chromosomal aspects of 20 cases observed in the region of Clermont-Ferrand in comparison with the bibliographical data.

The bone marrow smears and marrow biopsies of 30 unselected consecutive patients with a myelodysplastic syndrome have been classified retrospectively according to the proposals of the French-American-British cooperative group (FAB). The diagnoses according to the FAB classification were refractory anemia (RA) in 3, RA with ring sideroblasts (RAS) in 5, RA with excess of blasts (RAEB) in 14, REAB in transformation (RAEB-t) in 5, and chronic myelomonocytic leukemia (CMML) in 3. The group comprised 19 men and 11 women with a median age of 68 years. Of 22 patients, 9 died after progression to acute non lymphoblastic leukemia (ANLL), 7 from infections, 2 from bleeding and 4 from unrelated causes. Actuarial survival is 10.5 months, 8 patients being at risk at the time of evaluation. Although the small number of patients does not allow statistical evaluation, our results are similar to those in the literature: prognosis is less good with an increasing number of marrow blasts and degree of cytopenia, and the risk of progression to ANLL is higher for REAB-t and REAB patients. Of 4 patients treated with small doses of cytosine-arabinoside (Ara-C), one responded and remained stable without treatment for 7 months. 2 patients resistant to small-dose Ara-C showed complete response to subsequent high-dose Ara-C treatment.