Cytogenetic Abnormalities Predict Disease Progression in Primary Myelodysplastic Syndrome: A Multicentric Study in 508 Chinese Patients.

Myelodysplastic syndrome (MDS) is a clonal stem cell disorder characterized by ineffective hematopoiesis and frequent leukemia progression. Cytogenetic abnormalities are presented in MDS patients and predict poor prognosis. To better define their relevance to clinical outcome in Chinese patients with primary MDS, cytogenetic analysis was performed in 508 cases and retrospectively compared with clinical data. The median age was 49 years which was 10 years younger than that of western patients. The median overall survival was 34 (range 1–161) months, with the 2-year and 5-year survival rate of 50.0% and 15.0%, respectively. Among 367 cases with evaluable karyotype in bone marrow mononuclear cells, cytogenetic abnormalities were found in 136 of them (37.1%), including 56 cases (15.3%) of numeric abnormality and 80 cases (21.8%) of structural abnormality. Higher incidence of cytogenetic abnormality was found in RAEB-T (43/86, 50.0%) and RAEB (44/106, 41.5%) patients than that of RA patients (38/143, 26.6%). RAEB and RAEB-T had more cases of non-hypodipoidy, double aberrations with translocation, and complex aberrations. In RA, the most frequent aberrations were duplication and numeric changes. This study also showed RAEB appears to be the course of MDS that genome turbulence was under the evolution pressure. In RAEB-T, the genome abnormalities tend to be uniform and behaved as special translocation, which is in accordance with the clinical behavior of AL. Poor prognosis and early leukemia transformation were observed in the patients with cytogenetic abnormalities, especially with complex cytogenetic aberrations and chromosome translocations. In conclusion, cytogenetic abnormalities possess strong predictive value on disease outcome in primary MDS patients.