Childhood acute myeloid leukemia with CBFβ‐MYH11 rearrangement: Study of incidence, morphology, cytogenetics, and clinical outcomes of Chinese in Hong Kong

Abstract

We analyzed 43 consecutive cases of pediatric acute myeloid leukemia (AML) for the presence of the CBFb-MYH11 rearrangement using molecular techniques in a regional hospital in Hong Kong. Five cases (11.6%), 3 girls and 2 boys, ranging in age from 8 months to 14 years old, were found positive for the CBFb-MYH11 rearrangement. Morphologically, they were FAB M2 or M4 with or without eosinophilia (Eo). Typical M4Eo was observed in only one case. The molecular findings were in complete concordance with cytogenetic data, which revealed inv(16)(p13q22) in all and also gains of chromosome 4, 8, 22, and Y in one patient. Clinically, all 5 patients achieved complete remission after chemotherapy with favorable outcomes except for the patient with infantile AML, who relapsed 11 months after diagnosis, underwent cord blood transplantation, and was in second remission. This is the first clinicopathological study and documentation of the incidence of

High expression of microRNA‑500 is associated with poor prognosis in patients with acute myeloid leukemia receiving allogeneic hematopoietic stem cell transplantation

“…Thus, the results indicated that while allo-HSCT is an effective treatment strategy that may overcome the adverse effect of classical mutations, miR-500 is a more effective indicator of prognosis in patients with AML receiving allo-HSCT compared with the aforementioned mutations. The subgroup of patients with AML with inv(16)/CBBB-MYH11, one of the most common cytogenetic aberrations in AML, tend to have an improved prognosis compared with patients without this aberration (17). This was also observed for patients with a low expression level of miR-500 in the present study.…”

Cytogenetics of pediatric acute myeloid leukemia

“…Inv(16)(p13q22) and t(16;16)(p13;q22) are most commonly associated with acute myelomonocytic leukemia (AML‐M4) with abnormal eosinophils but have also been found in M0, M1, M2 and M5 (97). These rearrangements result in the fusion of the core binding factor β (CBFβ) gene at 16q22 to the smooth muscle myosin heavy chain (MYH11) gene at 16p13 (19, 97). The frequency of inv(16)/t(16;16) in children usually range from 3–8% but it was found to be higher in Chinese pediatric patients (11.6%)(14–17, 20, 30, 31, 39, 97–99).…”

“…These rearrangements result in the fusion of the core binding factor β (CBFβ) gene at 16q22 to the smooth muscle myosin heavy chain (MYH11) gene at 16p13 (19, 97). The frequency of inv(16)/t(16;16) in children usually range from 3–8% but it was found to be higher in Chinese pediatric patients (11.6%)(14–17, 20, 30, 31, 39, 97–99). Patients have a good prognosis with a significantly better remission induction rate and an higher OS rate than patients with normal karyotype (16, 17, 19).…”

Severe Eosinophilia in an Infant With Congenital Acute Myeloid Leukemia With t(3;4;6)(q26;q25;q21): A Case Report

“…18 In patients with M4, the bone marrow shows variable numbers of pathologic eosinophils, sometimes less than 5%; in these patients, eosinophils are not usually increased in the peripheral blood. Eosinophils are described as morphologically abnormal with cytologic abnormalities such as nuclear hyperlobulation and/or the presence of large proeosinophilic granules, and cytochemical abnormalities 19 (chloroacetate esterase, PAS, toluidine blue positive).…”