OBJECTIVETo investigate the biological characteristics and therapeutic efficacyt of acute erythroleukemia (AEL,AML-M6).

METHODSBlood cell count, liver function, lactate dehydrogenase level, coagulation, morphology, immunology, cell genetics and molecular biology were retrospectively analyzed in 103 cases of acute erythroleukemia patients admitted in our department from May 2016 to June 2009. The therapeutic efficacy was observed by means of remission rate, relapse rate, relapse-free survival and overall survival.

RESULTSThe medians of white blood cells, granulocyte, hemoglobin and platelet were 3.04×10/L, 0.67×10/L, 66 g/L, and 45×10/L,respectively. Nucleated red blood cells were found in the peripheral blood smears from 71.1% of AEL patients. None of the patients showed abnormal coagulation function. Flow cytometry analysis indicated that CD13 (93.5%),CD117(89.1%), HLA-DR(87.0%), and CD34 (80.0%) were highly expressed in AEL, and lymphoid antigens of CD4 (42.9%) and CD7(28.9%) were expressed in partial patients. Karyotype analysis in 82 patients showed 52.4% (43/82) normal karyotype, 41.5% (34/82) abnormal karyotype, and 6.1% (5/82) failed tests. In the 34 cases with abnormal karyotype, there were 14(41.2%) cases with simple chromosomal abnomality and 20(58.8%) cases with complex karyotype. The positive rate of fusion gene accounted for 16.7% in 60 patients, and the gene mutations accounted for 77.8% in 27 patients. Among 103 cases of AEL, 81 cases were treated with chemotherapy, but 66 cases can be used for therapeutic analysis, as a results the total complete remission rate derived from 2 courses of treatment was 45.5% (30/66). The relapse rate was 36.7% (11/30), and the median relapse time was 15.5 months (6.2-50 months). The median survival time of 66 patients for therapeutic analysis was 29 months. The median survival time of CR patients was very significantly longer than that of the non-CR patients(P=0.001). The 5 year survival rate of CR patients was 65%, the median time of relapse-free survival (RFS) was 46.2 months and 3-years RFS was 58%.

CONCLUSIONAEL is characterized by the highly expressed CD34 antigen, and complex karyotype. Although AEL has lower CR rate and poor prognosis, CR patients can achieve long-term survival and have good quality of life.