Clinical Characteristics and Prognosis of Acute Myeloid Leukemia Patients with inv(16)/t(16;16)(p13.1;q22) and/or CBFβ-MYH11 / 中国实验血液学杂志

OBJECTIVE@#To summarize the clinical and laboratory characteristics of patients with acute myeloid leukemia (AML) with inv(16)/t(16;16) (p13.1;q22), and to analyze the risk factors affecting the prognosis of the patients.@*METHODS@#AML patients with inv(16)/t(16;16) (p13.1;q22) and/or CBFβ-MYH11+ admitted to the Department of Hematology, The First Affiliated Hospital of Soochow University from January 1, 2008 to October 30, 2019 were retrospective analyzed, the clinical and laboratory indicators, as well as treatment plans and efficacy evaluations of the patients were all recorded. Furthermore, related factors affecting the overall survival (OS) and event-free survival (EFS) of the patients were analyzed.@*RESULTS@#Among 151 AML patients with inv(16)/t(16;16) (p13.1;q22) and/or CBFβ-MYH11+, the percentage of additional chromosomal abnormalities was about 27.8%, and the most common additional chromosomal abnormality was +22 (33/151, 21.8%), followed by +8 (11/151, 7.3%). There were 112 patients with perfect NGS examination, and the result showed the most common accompanying gene mutations were KIT mutation (34/112, 30.4%) and FLT3 mutation (23/112, 20.5%). Univariate analysis showed that factors affecting EFS included: NE≤0.5×109/L (P=0.006) and combined K-RAS mutation (P=0.002); Factors affecting OS included: Age≥50 years old (P<0.001) and NE≤0.5×109/L (P=0.016). Multivariate analysis showed that NE≤0.5×109/L (P=0.019) was the risk factors affecting OS. The proportion of bone marrow eosinophilia (BME)≥10.00% (P=0.029) was the risk factors affecting EFS.@*CONCLUSION@#The prognosis for those newly diagnosed AML patients who were of advanced age, the high proportion of bone marrow eosinophils, K-RAS mutations, and agranulocytosis is poor. The treatment plans can be adjusted in the early stage to improve the prognosis of such patients.

Haematological & molecular profile of acute myelogenous leukaemia in India.

Background & objectives: Recurrent balanced translocations are generally recognized to be a major parameter for prognostication in acute myeloid leukaemia (AML). The chromosomal translocation t(15;17) results in PML/RARα fusion gene, t(8;21) results in AML1/ETO fusion gene and Inv 16 generates CBFβ/MYH11 fusion gene. Patients with these mutations have a good prognosis unlike abnormalities in chromosome 5 or 7 or FLT3 genes. Therefore, we screened the AmL patients for known specific genetic abnormalities that could lead to more definitive prognoses. Methods: A total of 113 AML patients were evaluated at diagnosis based on routine morphology and cytochemistry and classified according to the WHO criteria. The distribution of AML subtypes was M1(1), M2(32), M3(57), M4(14), M5(1), M6(1) and seven cases where morphological subtype could not be classified. RT-PCR was performed to identify PML/RARα, AML1/ETO, CBFβ/MYH11 and FLT3 internal tandem duplication (ITD). Results: Of the 57 patients with M3 subtype, 55 had the PML-RARα fusion transcript. The prevalence of bcr3 (short isoform) was higher (62%) than that of bcr1 (long isoform) (38%) and no correlation was found with age, sex or white blood cell count. FLT3 internal tandem duplication (ITD) mutations were more frequent in patients with APL than in other AML subtypes (17.5 vs. 8.9%), the frequency greater in patients with bcr3 isoform (70%) than in those with in bcr1 isoform (30%). Patients with FLT3/ITD mutations had a significantly higher median white cell count than those without these mutations (55 x 109/l vs. 6.3 x 109/l; P<0.001). More patients with FLT3/ITD mutations died early (53%) than those without these mutations (16%) (P<0.01). AML1-ETO fusion transcript was detected in 16 of 56 patients with no correlation with clinical or haematological parameters. Interpretation & conclusion: The results of the present study showed presence of bcr3 (short isoform) higher than bcr1 (long isoform). FLT3 internal tandem duplication (ITD) mutation was predominant in acute promyelocytic leukaemia patients with bcr3 isoform. Thus, patients with APL who have FLT3 mutation appear to have a poorer prognosis. Therefore, rapid identification of specific translocations at diagnosis is important for prognostic purposes and their detection should be incorporated into routine assessment.