Clinical and laboratorial characteristics analysis on 15 cases of acute myeloid leukemia with Ph chromosome and BCR-ABL gene positive

Abstract

Objective To investigate the clinical and laboratory characteristics of patients with Ph chromosome/BCR-ABL gene-positive acute myeloid leukemia (Ph/BCR-ABL+ AML). Methods The clinical date of 15 primary patients with Ph/BCR-ABL+ AML were collected to retrospectively analyze the cell morphology, cytogenetics and cellular immunophenotyping, clinical features and prognosis. Results The detection rate of Ph+ AML patients among AML in the same period was 1.47% (15/1 018). The results showed that 15 patients (8 males and 7 females) were diagnosed as Ph/BCR-ABL+ AML, whose median age was 38 years old and median white blood cell count was 38×109/L; 6 cases (40%) were extramedullary infiltration; according to French-American-Britain classification style, there were 8 cases of M2 (53.3%) and 4 cases of M4 (26.7%). Immnologic analysis showed that 15 Ph+ AML patients expressed myeloid antigens and CD34, of which 3 cases were immunophenotyped with myeloid and lymphoid cell antigens. In the initial diagnosis Ph positive chromosome can be detected in the 15 patients, and some chromosomes were associated with additional chromosomal abnormalities in 3 cases. BCR-ABL fusion gene transcript positive were detected in all cases, with P190BCR-ABL in 4 cases (26.7%), P210BCR-ABL in 11 cases (73.3%), among which 1 case coexpressed CBFβ-MYH11. Four out of 8 cases had AML-like gene mutations. Nine of 15 patients were completely relieved after one course of induction therapy. The complete remission (CR) rate (85.7%) in chemotherapy combined with tyrosine kinase inhibitor (TKI) group was better than that in signle chemotherapy group (37.5%), but the difference was not statistically significant (P=0.12). Median survival time of chemotherapy combined with TKI group (13 months) and chemotherapy combined with hematopoietic stem cell transplantation (HSCT) group (60 months) were both better than that of single chemotherapy group (8 months), P=0.0064, 0.0400. At the end of the follow-up, all patients in chemotherapy combined with TKI group and HSCT groups survived. Conclusions There are special characteristics in the clinical symptoms, cellular immune phenotypes and morphology of Ph/BCR-ABL+ AML. Routine screening of BCR-ABL fusion gene, AML common mutant gene and the chromosome provides more evidence for early diagnosis of leukemia. Efficacy on Ph/BCR-ABL+ AML is poor and survival time is short, but implement allogeneic hematopoietic stem cell transplantation after chemotherapy combined with TKI could improve prognosis. Key words: Ph chromosome; Acute myeloid leukemia; BCR-ABL fusion gene