OBJECTIVETo analyze the clinical and laboratory features of acute myeloid leukemia (AML) with cuplike nuclei morphology.

METHODSOne hundred and seventy patients diagnosed with AML (M1andM2) between December 2009 and December 2016 were included in the study. Bone marrow smears were prepared for morphologic alanalysis, the immunophenotype was analyzed by flow cytometry and the RHG-banding was for conventional cytogenetic assay (CCA) ,gene mutation was detected by sequencing.

RESULTSAmong the 170 AMLpatients, 67 were diagnosed as M1 and 103 patients was diagnosed as M2, 43 patients(25.3%) defined as cuplike nuclei-positive, among them 38patients (88.4%) were M1 while only 5 patients (11.6%) were with M2(P<0.01). No significant value about sex(P> 0.05) between cuplike nuclei-positive and -negative group, while older patients were found in cuplike nuclei-positive group (P<0.05). Higher peroxydas (POX) ratio (P<0.05) and integration (P<0.05) were found in cuplike nuclei- positive group. Furthermore, the patients with cuplike nuclei-positive lack the expressions of CD34 (P<0.01) and HLA-DR(P<0.01) while no other immunophenotype markers were found. Among the 152 patients (89.4%) for genetic analysis ,83.8% karyotype of the cuplike nuclei-positive group were normal while only 54.8 of negative group was normal by CCA. Molecular biology analysis showed that the patients in cuplike nuclei-positive group have significantly highe rNMP1 (P<0.01) and FLT3(P<0.01) mutations as compared with the negative group. Furthermore, the relationship of the ratio o fcuplike nuclei and the type of gene mutations were investigated, and no significant associations were found. However, it was found that the patients with FLT3 mutation displayed more biological nuclear invagination than the patients with NPM1 mutations (P<0/01).

CONCLUSIONAML patients with positive cuplike nuclei have characteristic morphological changes, typical immunophenotype with HLA-DR- and CD34, normal karyotype accompanied by NPM1 and FLT3 mutations.