OBJECTIVETo investigate the prognostic value of quantitative chromosomal abnormality in myelodysplastic syndromes (MDS).

METHODSChromosomal karyotypes in seventy-one MDS patients' were analyzed quantitatively. Based on the number of abnormal metaphase in 20 counted metaphases, the patients were divided into three groups: no abnormal karyotypes, abnormal metaphases less than or equal to five, and that more than five. The leukemia transformation rate, death rate and survival time between these three groups were compared.

RESULTSForty-four cases (62.0%) had abnormal karyotypes. The incidences of abnormal karyotypes in RA, RCMD and RAEB were 76.9%, 55.8% and 75.0%, respectively, being no significant difference (P > 0.05). Among the abnormal karyotypes, complex abnormality with two or more abnormal karyotypes was most common and accounted for 47.7%. The frequencies of trisomy 8, monosomy 7 and del 20q were 18.2%, 4.5% and 4.5%, respectively. Other kinds of abnormal karyotypes totally accounted for 25%. There were 27 cases of group 1, 28 of group 2 and 16 of group 3. Eighteen cases (25.4%) transformed to acute leukemia. The incidences of leukemia transformation in group 1, 2 and 3 were 18.5%, 25% and 37.5%, and the death rates were 29.6%, 42.9% and 56.3%, respectively. The median survival times were 60, 47 and 24 months respectively.

CONCLUSIONThe quantitative chromosome abnormality has prognostic value in MDS.