Phenotypic and genetic analysis of acute megakaryoblastic leukemia in young children with WT1, MLL-PTD and EVI1 genes / 中华医学遗传学杂志

OBJECTIVE@#To explore the phenotypic and genetic characteristics of acute megakaryoblastic leukemia (AMKL) in young children accompany by WT1, MLL-PTD and EVI1, in order to improve the diagnosis level of AMKL.@*METHODS@#EDTA-K@*RESULTS@#White blood cell count was 12.3× 10@*CONCLUSION@#Acute megakaryocytic leukemia has unique and complex phenotypic and genetics characteristics.

Analysis of Clinical Characteristics and Prognosis in Children with Acute Megakaryoblastic Leukemia without Down Syndrome / 中国实验血液学杂志

OBJECTIVE@#To analyze the clinical characteristics and treatment effects of children with acute megakaryoblastic leukemia without down syndrome (non-DS-AMKL).@*METHODS@#The clinical data of 19 children with non-DS-AMKL treated in the Pediatric Hematology Ward in Sun Yat-sen Memorial Hospital of Sun Yat-sen University from May 2008 to April 2018 were analyzed retrospectively. The clinical characteristics, laboratory test and treatment methods of the children were concluded. All patients were followed up to evaluate the effect of treatment.@*RESULTS@#The 19 cases of children included nine male and ten female, the median age of onset was 2 years old. The clinical manifestations showed nonspecific. The median white blood cell of peripheral blood was 15.88×10@*CONCLUSION@#Non-DS-AMKL was rare in children and difficult to be diagnosed. Determination of MICM classification as early as possible was helpful for diagnosis, and genetic testing played an important role for diagnosis and prognosis evaluation. Early hematopoietic stem cell transplantation in patients with CR after chemotherapy might be an effective way to cure AMKL.

Clinical features and prognosis of pediatric acute megakaryocytic leukemia / 中国当代儿科杂志

OBJECTIVE@#To study the clinical features and prognosis of children with acute megakaryocytic leukemia (AMKL) and the clinical effect of acute myeloid leukemia 03 (AML03) regimen for the treatment of pediatric AMKL.@*METHODS@#The clinical data were collected from 47 children with AMKL who were diagnosed from May 2011 to December 2019. The treatment outcomes and prognostic factors were analyzed. The Kaplan-Meier method and the log-rank test were used for survival analysis.@*RESULTS@#Among the 47 children with AMKL, 22 with non-Down syndrome-AMKL were treated by the AML03 regimen, with a median follow-up time of 11.4 months. For the 22 non-Down syndrome-AMKL patients, the remission rate of bone marrow cytology was 85% and the negative rate of minimal residual disease (MRD) was 79% after induction Ⅱ, with a 2-year overall survival (OS) rate of (50±13)% and a 2-year event-free survival (EFS) rate of (40±12)%. The group with positive immunophenotypic marker CD56 had significantly lower 2-year EFS and OS rates than the group with negative CD56 (@*CONCLUSIONS@#Children with AMKL tend to have a low remission rate and a poor prognosis. Positive immunophenotypic marker CD56, bone marrow cytology during early treatment response, and MRD results are important factors influencing the prognosis. Allogeneic hematopoietic stem cell transplantation has no significant effect on the prognosis of AMKL.

Analysis on the laboratory examination characteristics in 22 patients with acute megakaryoblastic leukemia / 中华血液学杂志

<p><b>OBJECTIVE</b>To analyze the ultra microstructures and the expression of platelet peroxidase (PPO) of megakaryocytes from bone marrow, their clinical manifestations and laboratory characteristics in patients with acute megakaryoblastic leukemia (AMKL).</p><p><b>METHODS</b>Karyocytes from bone marrow of 22 AMKL patients were divided into two parts by lymphocyte separation liquid, one part was used to prepare the ordinary transmission electron microscope specimens to observe the morphological structures of megakaryocytes, the other was used to prepare the histochemical specimens of platelet peroxidase to analyze the positive reaction of PPO in AMKL, which were coupled with the patients' data of with bone marrow morphology, cell chemistry, and chromosome karyotype examination.</p><p><b>RESULTS</b>Megakaryocytes from 17 of 22 patients were in the first stage, less than 20 µm in diameter, the nucleis were round, the cytoplasm contained microtubules, membranous vesicles and minute dense granules, no demarcation membrane system and surface-connected canalicular system, less dense granules and α-granules; Megakaryocytes in 5 cases were mainly in the first stage, while containing second and third stage megakaryocytes; the positive rate of PPO in megakaryocytes of 22 patients was 0-80%. The primitive and naive megakaryocytes were found in bone marrow smears of 22 cases, CD41 staining of the megakaryocytes was detected in the primitive and naive megakaryocytes, and more complex chromosome karyotype anomalies were observed.</p><p><b>CONCLUSION</b>The majority of megakaryocytes in AMKL patients were the first stage ones, the rest were second and third stage ones, and the positive PPO reaction was significantly different. CD41 staining of the megakaryocytes was specific with complex chromosome karyotypeswere.</p>

Gen de fusión AML-1/ETO y mutación NPM-1A en leucemia mieloide crónica en crisis blástica mieloide / AML-1/ETO fusion gene and mutation NPM-1A in myeloid chronic leukemia in myeloid blast crisis

La leucemia mieloide crónica es una neoplasia mieloproliferativa de naturaleza clonal que generalmente y de manera progresiva transita por tres fases: crónica, acelerada y crisis blástica. Alrededor del 80 por ciento de los enfermos con leucemia mieloide crónica son diagnosticados durante la fase crónica, 10 por ciento en fase acelerada y otro 10 por ciento durante la crisis blástica. A la presencia del cromosoma Filadelfia y la formación del gen de fusión BCR/ABL, que se traduce en la proteína quimérica pBCR/ABL, le sigue una gran inestabilidad genómica y la adquisición de alteraciones cromosómicas y moleculares adicionales. Algunas alteraciones moleculares, que suelen estar presentes en otras hemopatías malignas, pueden ser adquiridas durante la progresión de la leucemia mieloide crónica a crisis blástica. Se presenta el caso de un paciente que debutó con una leucemia mieloide crónica en crisis blástica, con positividad del gen de fusión BCR/ABL, el gen de fusión AML-1/ETO y la mutación NPM-1A(AU)

Chronic myeloid leukemia is a clonal myeloproliferative neoplasm which generally and progressively goes through three phases: chronic, accelerated and blast crisis. About 80 percent of patients with chronic myeloid leukemia are diagnosed in chronic phase, 10 % in accelerated phase and 10 percent in blast crisis. The presence of Philadelphia chromosome and the formation of BCR/ABL fusion gene, resulting in the chimeric protein pBCR/ABL, generates a large genomic instability and the acquisition of additional chromosomal and molecular alterations. Some molecular alterations, which are usually present in other hematological malignancies, could be acquired during the progression of chronic myeloid leukemia to blast crisis. This report presents the case of a patient with de novo chronic myeloid leukemia in blast crisis, with positivity of BCR/ABL fusion gene, AML-1/ETO fusion gene and mutation NPM-1A(AU)

An Unusual Case of Myeloperoxidase-Positive Acute Megakaryoblastic Leukemia

No abstract available.

Re: Lee H, et al. An Unusual Case of Myeloperoxidase-Positive Acute Megakaryoblastic Leukemia. Ann Lab Med 2015;35:466-8

No abstract available.

Constitutional Chromosomal Abnormality Identified in a Sibling Donor After Bone Marrow Stem Cell Transplantation in a Pediatric Patient with Acute Megakaryoblastic Leukemia

No abstract available.

A Case of Pentasomy 21 With Two Isochromosome 21s in Acute Megakaryoblastic Leukemia Associated With Down Syndrome

No abstract available.

Therapy-Related Acute Megakaryoblastic Leukemia in a Lung Cancer Patient

No abstract available.

Acute Megakaryoblastic Leukemia with CD41a-/CD61-/CD42a+ Blasts in an Infant with Down Syndrome

Infants with Down syndrome have increased incidences of transient abnormal myelopoiesis (TAM) and acute leukemia, which are usually associated with acute megakaryoblastic leukemia (AMKL). A 5-day-old girl with Down syndrome was diagnosed with TAM; 4 months later, acute leukemic transformation was suspected. Bone marrow (BM) examination was performed, and the infant was diagnosed with acute leukemia (80% blasts). Although BM aspirates showed the presence of megakaryocytic blasts with cytoplasmic blebs, flow cytometry analysis revealed that they were negative for cells with CD41a and CD61 immunophenotypes. Further analysis revealed that the megakaryocyte-related marker CD42a was positive in 57% of blasts. Morphologic and immunophenotypic features are required to establish the lineage of megakaryocytic blasts, which are necessary for diagnosing AMKL. As most cases of AMKL were positive for CD41 and/or CD61 markers, their presence was evaluated during routine analysis. In order to identify the immunophenotypic features of AMKL in an infant with Down syndrome, we performed additional flow cytometry for CD42a, one of the megakaryocytic markers, and were able to assist in the early diagnosis of AMKL, as well as to use CD42a as an effective follow-up marker.

Mycophenolate Mofetil for Treatment of Autoimmune Hemolytic Anemia and Nephrotic Syndrome after Cord Blood Transplantation / 대한수혈학회지

We report on a 2-year-old girl who developed autoimmune hemolytic anemia, which occurred with minimal change nephrotic syndrome 3 months after umbilical cord blood transplantation for acute megakaryocytic leukemia. Because the disease is regarded as chronic graft versus host disease and developed while taking cyclosporine medication, she was treated with methylprednisolone 2 mg/kg/day. However, hemolysis and proteinuria were refractory to steroid treatment. One week after starting methylprednisolone, mycophenolate mofetil was added. Hemolysis and proteinuria showed improvement after 2 weeks of mycophenolate mofetil medication.

Caracterización de mutaciones en el gen GATA-1 en pacientes con Síndrome de Down y diagnóstico de mielopoyesis anormal transitoria o leucemia megacarioblástica aguda / Mutation characterization in the GATA-1 gene in patients with Down's Syndrome diagnosed with transient abnormal myelopoiesis or acute megakaryoblastic leukemia

Los pacientes con síndrome de Down tienen un riesgo más elevado de presentar leucemia megacarioblástica aguda (LMCA). Un 10% de los recién nacidos con ese síndrome presentan un cuadro de mielopoyesis anormal transitoria (MAT), indistinguible de la LMCA, que en general remite espontáneamente. En ambos grupos de pacientes se describió una alta incidencia de mutaciones en el gen GATA-1. Se analizaron 14 muestras de ADN de médula ósea (10 MAT/4 LMCA) correspondientes a 13 pacientes con Síndrome de Down mediante PCR y secuenciación, para describir la frecuencia y las características de las mutaciones en el gen GATA-1 en la población estudiada y sus consecuencias a nivel proteico. Se detectaron mutaciones en 10 de 10 MAT y en 3 de 4 LMCA, que a nivel proteico originarían un codón de terminación prematuro (n= 5), alteraciones en el sitio de corte y empalme (splicing) (n= 6) o cambio de secuencia (n= 3). Se confrmó la alta frecuencia de mutaciones en el gen GATA-1 en recién nacidos con Síndrome de Down y MAT o LMCA.

Patients with Down's Syndrome have a higher risk of developing acute megakaryoblastic leukemia (AML). Ten per cent of newborn infants with this syndrome have transient abnormal myelopoiesis (TAM), indistinguishable from AML, which generally remits spontaneously. A high incidence of GATA-1 gene mutations was described in both groups of patients. Fourteen bone marrow DNA samples (10 ATM/4 AML) were analyzed by PCR and sequencing; these samples were obtained from 13 patients with Down's Syndrome to describe the rate and mutation characteristics of the GATA-1 gene in the studied population and its consequences at a protein level. Mutations were detected in 10 out of 10 TAM and in 3 out of 4 AML, which at a protein level would result in an early termination codon (n= 5), alterations in the splicing site (n= 6) or sequence change (n= 3). The high rate of GATA-1 gene mutations was confirmed in newborn infants with Down's Syndrome and MAT or AML.

GATA1-positive Acute Megakaryoblastic Leukemia in a 6.9-year-old Patient with Down Syndrome: What is the Prognosis? / 임상소아혈액종양

We describe a very rare case of 6.9-year-old boy with Down syndrome (DS) and a prior history of transient myeloproliferative disorder. He was diagnosed with acute megakaryoblastic leukemia and found to have a novel GATA1 gene mutation, as well as a complex karyotype without recurrent acute myeloid leukemia (AML) aberrations. The patient achieved an early bone marrow response to chemotherapy. However, relapse occurred during treatment, 9 months after the initial diagnosis. Although GATA1 mutations are closely associated with DS-AML, we speculate that factors other than the presence of the GATA1 mutation can affect the overall outcome in older pediatric patients.

GATA1-positive Acute Megakaryoblastic Leukemia in a 6.9-year-old Patient with Down Syndrome: What is the Prognosis? / 임상소아혈액종양

We describe a very rare case of 6.9-year-old boy with Down syndrome (DS) and a prior history of transient myeloproliferative disorder. He was diagnosed with acute megakaryoblastic leukemia and found to have a novel GATA1 gene mutation, as well as a complex karyotype without recurrent acute myeloid leukemia (AML) aberrations. The patient achieved an early bone marrow response to chemotherapy. However, relapse occurred during treatment, 9 months after the initial diagnosis. Although GATA1 mutations are closely associated with DS-AML, we speculate that factors other than the presence of the GATA1 mutation can affect the overall outcome in older pediatric patients.

Development of Acute Megakaryoblastic Leukemia with Isochromosome (12p) after a Primary Mediastinal Germ Cell Tumor in Korea

The association of hematological malignancies with a mediastinal germ cell tumor (GCT) is very rare. We report one case of a young adult male with primary mediastinal GCT who subsequently developed acute megakaryoblastic leukemia involving isochromosome (12p). A 25-yr-old man had been diagnosed with a mediastinal GCT and underwent surgical resection and adjuvant chemotherapy. At 1 week after the last cycle of chemotherapy, his peripheral blood showed leukocytosis with blasts. A bone marrow study confirmed the acute megakaryoblastic leukemia. A cytogenetic study revealed a complex karyotype with i(12p). Although additional chemotherapy was administered, the patient could not attain remission and died of septic shock. This case was definitely distinct from therapy-related secondary leukemia in terms of clinical, morphologic, and cytogenetic features. To our knowledge, this is the first case report of a patient with mediastinal GCT subsequently developing acute megakaryoblastic leukemia involving i(12p) in Korea.

Long-term Complete Remission in a 71-year-old Patient with AML-M7 after Low-dose Cytarabine Induction and Intermediate-dose Cytarabine Consolidation Treatment

The authors describe the case of a 71-year-old patient with acute megakaryocytic leukemia (AML-M7) who was successfully treated with low-dose cytarabine induction followed by intermediate-dose cytarabine consolidation therapy. The patient presented with infection and rapidly increasing blood blasts. The diagnosis was consistent with AML-M7 with a normal karyotype. Peripheral blood blasts decreased rapidly upon low-dose cytarabine administration, and the patient achieved complete remission after two courses of low-dose cytarabine (10 mg/m2 bid for 12 days). Consolidation therapy with intermediate-dose cytarabine (1.0 g/m2 bid on day 1, 3 and 5) was then instituted without serious complication. He remained in complete remission at the time of writing 47 month after diagnosis. In spite of multiple poor prognostic factors, this patient showed excellent treatment outcome through low-dose cytarabine induction and intermediate- dose cytarabine consolidation. It needs to be validated whether acute leukemia with a megakaryocytic morphology is exceptionally sensitive to cytarabine.

Rastreamento de mutações no gene GATA1 em crianças com síndrome de Down

Crianças com síndrome de Down (SD) apresentam um risco 10 a 20 vezes maior de desenvolver leucemia do que crianças normais, particularmente a leucemia megacarioblástica aguda (LMA-M7) e uma forma reversível denominada doença mieloproliferativa transitória também conhecida como leucemia transitória (LT), devido ao fato de que geralmente há uma remissão espontânea dentro de 3 meses. A LT pode ser considerada uma pré-condição leucêmica, já que cerca de 20% dos pacientes podem desenvolver a LMA-M7 no prazo de 4 anos. Recentemente, foi relatado que mutações somáticas no GATA1, localizado no cromossomo X, estão presentes tanto em blastos de LT quanto em LMA-M7 de crianças com SD. O GATA1 é um fator de transcrição e está presente na diferenciação normal das linhagens eritróides e megacariocíticas. O modo pelo qual as alterações no GATA1 contribuem para a leucemia ainda é desconhecido. A partir disso, estabelecemos um programa nacional, a fim de determinar a incidência de mutações no GATA1 (éxons 2 e 3) em uma coorte de recém-nascidos com SD. Para isso, utilizamos a técnica de cromatografia líquida desnaturante de alta performance (dHPLC) e seqüenciamento automático. Esta técnica de dHPLC se baseia nas variações de heteroduplex e homoduplex dos fragmentos de DNA e apesar de o seqüenciamento automático ser o padrão ouro para a identificação de mutações, este método pode ser lento quanto à análise da mutação, ao passo que o dHPLC tem se mostrado eficaz e rápido para a análise das variações genéticas de diversos genes de interesse médico. Para este estudo utilizamos medula óssea e/ou sangue periférico de 111 crianças com SD (recém-nascidos e crianças sendo a grande maioria com menos de 4 anos de idade) obtidos entre janeiro de 2000 e dezembro de 2007, sem tratamento prévio. Um total de 127 amostras de crianças com SD foram analisadas, sendo 66 crianças com SD e doenças hematológicas identificadas clinicamente e 61 recémnascidos com SD e sem evidência clínica de doenças hematológicas. A análise através do dHPLC e seqüenciamento automático identificou dezenove mutações no éxon 2 exclusivamente em crianças com LT e LMA-M7 com SD e em uma criança com LT e SD foi detectada alteração no éxon 3.A freqüência de anomalias genéticas não foi estatisticamente significativa em relação ao sexo ou cor da pele e alterações no GATA1 não foram detectadas em nossa coorte de recém-nascidos sem sinal de distúrbios hematológicos. A concordância da detecção através da técnica de dHPLC foi de 100% com o seqüenciamento automático. Em conclusão, nossos resultados indicam que alterações no GATA1 são especificas do subtipo LMA-M7 e LT da SD e que a técnica de dHPLC é eficaz e uma valiosa ferramenta para análise mutacional no GATA1 e, além disso, podemos consolidar o GATA1 como um marcador molecular com o intuito de uniformizar os critérios diagnósticos precoces da criança com SD melhorando assim sua taxa de sobrevida.

Children with Down syndrome (DS) have a 10 to 20-fold elevated risk of developing leukaemia, particularly acute megakaryoblastic leukemia (AMKL) and a reversible form of myeloproliferative disorder, known as transient leukemia (TL), which usually spontaneous resolves within 3 months. TL can be considered a preleukemic condition, as approximately 20% of TL patients will develop AMKL within 4 years. Recently, it has been reported that somatic mutations in the X-linked GATA1 gene are present in TL and AMKL blasts of DS infants. GATA1 gene encodes a transcription factor that is critical for normal development of erythroid and megakaryocytic lineages. The precise pathway by which mutagenesis of GATA1 contributes to leukemia is still unknown. Then, we established a national program in order to determine the incidence of GATA1 mutations in a cohort of DS newborns and children with DS presenting hematological disorders, furthermore we have evaluated the efficacy of denaturing high-performance liquid chromatography (dHPLC) screening method for detecting mutations in GATA1 gene. Bone marrow and/or peripheral blood from 111 DS children (newborns and children with the vast majority less than 4 years old) obtained between January 2000 and December 2007 without previous treatment. They were screened for GATA1 mutations (exons 2 e 3) by the denaturing High-Performance Liquid Chromatographic (dHPLC) and direct sequencing in an automated sequencer. dHPLC has been developed to screen for DNA variations by separating heteroduplex and homoduplex DNA fragments by ion-pair reverse-phase liquid chromatography. Although the automatic sequencing is the gold standard technique for identifying mutations, this method can be time consuming for analysis, while the dHPLC was effective and fast for the analysis of genetic variations A total of 127 samples from DS children were analyzed, with 66 DS children with hematological disorders identified clinically and 61 newborns without clinical evidence of hematological disorders by dHPLC and direct sequencing methods. Nineteen mutations were detected exclusively in exon 2 of DS children with AMKL nd TL disorders and one was detected in exon 3 of DS child with TL. The frequency of genetic abnormalities was no statistically significant regarding to sex or ethnicityand GATA 1 mutation was not detected in our cohort of newborns without sign of hematological disorder. The overall detection rate of dHPLC screening was 100%. In conclusion, our results indicate that dHPLC is an efficient and valuable tool for GATA1 mutational analysis.

GATA1 Mutation in Transient Myeloproliferative Disorder of Down Syndrome

Children with Down syndrome (DS) have a higher risk of developing leukemia than do healthy children, and they especially have a higher risk for developing transient myeloproliferative disorder (TMD) or acute megakaryocytic leukemia (AMKL). In recent studies, it has been reported that most of these patients have acquired mutation of the GATA1 gene, which encodes the erythroid/megakaryocytic transcription factor GATA1. GATA1 mutations have not been found in AMKL patients who did not have DS and other hematologic malignancies in DS. Most of the GATA1 mutations in DS-TMD/AMKL are nonsense mutations that are mainly located in exon 2. We observed a nonsense mutation in exon 2 of GATA1 [c.189_190delCA (Tyr63X)] in one case of DS-TMD. The GATA1 mutation has been thought to be an early event in the leukemogenesis of DS-TMD/AMKL and it could be used as a stable molecular marker to assess the treatment response or to monitor for the recurrence of DS-TMD/AMKL.