Cytogenetic Analysis of 1863 Chineses Patients with Chronic Myeloid Leukemia

Cytogenetic analyses of chronic myeloid leukemia (CML) have been performed previously in a large number of reports, but systematical research based on large sample sizes is seldom available. In order to further elucidate the cytogenetic nature of CML, we analyzed retrospectively the cytogenetic profiles of 1863 Ph/BCR-ABL-positive CML patients from a research center in China.

Of 1266 newly diagnosed CML patients, the median age was 41 years, which is younger than the median age of diagnosis in western populations. The incidence of additional chromosome abnormalities(ACAs) was 3.1% in newly-diagnosed chronic phase(CP), 9.1% in CP after therapy, 35.4% in accelerated phase(AP) and 52.9% in blast phase(BP), reflecting cytogenetic evolution with CML progression. 5.3% patients harbored a variant Ph translocation. A higher prevalence of ACAs was observed in variant Ph translocations than in classical t(9;22) in the disease progression, especially in BP(88.2% vs. 50%, p=0.002). Moreover, a hyperdiploid karyotype and trisomy 8 were closely correlated with myeloid blast crisis(BC) while a hypodiploid karyotype and monosomy 7 were associated with lymphoid-BC. Among subsets of myeloid-BC, compared with myeloid-BC with granulocytic differentiation or monocytic differentiation, myeloid-BC with minimal differentiation had higher ACAs rate (80% vs.46.8%, p=0.009 and 80% vs. 42.9%, p=0.006).

CML tends to afflict younger population in China. In the disease progression, the incident of ACAs was higher in variant Ph translocations than in classical t(9;22). Among subsets of myeloid-BC, myeloid with minimal differentiation had distinct cytogenetic features.

No relevant conflicts of interest to declare.