An autopsy case of acute mixed lineage leukemia with monosomy 7 in a child

A five-year-old boy initially diagnosed common ALL was developed to acute myelomonocytic leukemia. At onset, the bone marrow was hypercellular and 77% of the cells were blasts, mainly lymphoblast-like cells and cytogenetic study demonstrated 45, XY, -7 in all blasts. Cytochemically most of those blasts were negative for peroxidase, sudan black B, alpha-NB esterase staining. The immunological phenotype was J5 (CD10)+, I2 (HLA-DR)+, SmIg-, CyIgmu-, Leu1 (CD5)-, OKT11 (CD2)-, MY7 (CD13)-, suggesting common ALL. Eight months later, the bone marrow cells were occupied with large sized blasts which were almost positive for peroxidase stain and the cells showed coexpression of Mo1 (CD11b)+, MY4 (CD14)+, MY7+, MY9 (CD33)+, MCS2 (CD13)+, I2+, J5-, B4 (CD19)-, Mo2 (CDw14)-, at relapse. He died 2 years and 6 months after his initial diagnosis. An autopsy was performed which revealed generalized infiltration of leukemic cells and aspergillosis of the lung. In general, monosomy 7 is associated with myelodysplastic syndrome in childhood, and is terminated to acute myeloblastic leukemia. In this case, bone marrow blasts demonstrated monosomy 7 cytogenetically, and this case was considered as an acute mixed lineage leukemia of bilineal type. And this case proved that a monosomy 7 can also be terminated to acute mixed lineage leukemia with both lymphoid and myeloid phenotypes.     

Flow cytometric scoring system (FCMSS) assisted diagnosis of myelodysplastic syndromes (MDS) and the biological significance of FCMSS‐based immunophenotypes

In the myelodysplastic syndromes (MDS), the haematopoietic cells show various levels of abnormal maturation and differentiation, which can be detected by flow cytometry. Testing the anomalies of stage‐ or lineage‐specific surface antigens in CD34⁺ blasts can distinguish MDS from non‐clonal cytopenic diseases, and also reflect the pathological characteristics of MDS as a class of clonal diseases for providing new clues to basic research. The present study established a flow cytometric scoring system (FCMSS) based on theproportion and antigenic co‐expression of CD34⁺ blasts. This FCMSS showed good sensitivity and specificity (77·8% and 100%) in the assisted diagnosis of low‐risk MDS without chromosome anomalies, ringed sideroblasts and excess marrow blasts. Moreover, we explored and reported different modes of abnormal expression of CD34⁺ blasts antigens in different disease stages and analyzed the biological significance of the immunotypes for the first time. We found expression of mature myeloid antigens and lymphoid antigens gradually decreased, and early functional antigens gradually increased from low‐risk MDS with normal karytype to low‐risk MDS with abnormal karyotype then to high‐risk MDS. The patients with higher FCM scores were generally accompanied with HLA‐DR15 allele or hypocellular marrow. Evolution of clones and immunological factors might have influence on expression of antigens in CD34⁺ blasts.     

Transformation of severe aplastic anemia to myelodysplastic syndrome with monosomy 7 in a patient who achieved transfusion independence after immunosuppressive therapy

A 72-year-old woman was given a diagnosis of severe aplastic anemia, and treated with anabolic steroid and cyclosporin A starting in October 1996. Because this treatment was ineffective, anti-thymocyte globulin (ATG) therapy was started in September 1997. In May 1998, chromosome analysis revealed transformation to myelodysplastic syndrome (MDS), refractory anemia with excess of blasts with monosomy 7 in 60% of metaphase cells. The patient showed gradual hematologic improvement and became transfusion independent. Despite progression to acute myeloid leukemia (FAB-M6) with monosomy 7 in 100% of metaphase cells in December 1998, the hemoglobin level recovered to 13.2 g/dl. In May 1999 the blasts increased rapidly and transformation to acute myelomonocytic leukemia (FAB-M4) was diagnosed. The patient was treated with low-dose Ara-C and aclarubicin with no improvement and died in August 1999. This case demonstrated the transformation of severe aplastic anemia to acute myeloid leukemia via MDS with monosomy 7 associated with transfusion independence after immunosuppressive therapy. These findings suggested a close relationship between aplastic anemia and hypoplastic MDS and the possibility of hematologic improvement based on the growth advantage of abnormal clones.     

What biologic factors predict for transformation to AML?

Transformation of myelodysplastic syndromes (MDS) into secondary acute myeloid leukemia (sAML) is defined by an arbitrary boundary of ≥20% bone marrow blasts but does not necessarily reflect a defined biological transition. The more obvious distinction lies between MDS patients that have an isolated bone marrow failure phenotype and those with excess blasts. Subtyping of MDS might be more accurately stratified into clonal cytopenias and oligoblastic leukemias, using the degree of dysplasia and blast percentage as risk features, respectively, rather than as diagnostic criteria. Transformation from MDS to sAML often involves clonal evolution or expansion of existing subclones that can be assessed by changes in variant allele frequencies of the somatic mutations that define them. There are a number of predictors for transformation that have been identified: these include mutations of genes in growth signaling pathways (NRAS, KRAS, PTPN11, FLT3), mutations in genes more commonly observed in AML (NPM1, WT1, IDH2), certain cytogenetic abnormalities (monosomy 7, complex karyotype, loss of 17p). Gene expression profiles that divide MDS into two major categories identify a progenitor gene signature subtype associated with a high risk of AML transformation. Assessing for these genetic abnormalities may better identify MDS patients at greatest risk of transformation.     

Mixed blast crisis with the cytogenetic evidence of three clonal evolutions

A 46-year-old man was diagnosed as having chronic myelogenous leukemia (CML) in chronic phase in Dec. 1985. In Dec. 1987, anemia and leukocytopenia progressed, and the percentage of blast cells increased in the bone marrow. The blast cells were lymphoblastoid and positive for TdT. It was treated as a lymphoid crisis with vincristine and prednisolone, and complete remission was achieved. However, the blasts (11%) were observed in the bone marrow in Mar. 1988, and the chromosomal analysis revealed 46, XY, t (2q-; 11q+), t (9q+; 22q-) in 13 out of 20 cells. In June, the percentage of the blasts increased again, but chromosomal analysis showed a different karyotype, 46, XY, t(2p-; 11p+), t(9q+; 22q-) which was observed in 9 out of 10 cells. Then, myeloblastoid cells increased rapidly in spite of the chemotherapy in Dec. 1988. The chromosomal analysis showed 46, XY, 2p-, 7q-, 9q+, 11p+, 22q- in all analyzed cells. The rearrangement of the bcr gene could be detected by the Southern blotting. The blasts were positive for CD7, CD11, CD13, CD33, CD36, CD41 and CD42, suggesting that the blasts had the surface phenotypes of both myeloid and megakaryocytoid-lineage. This is a case with the mixed blast crisis that changed from the lymphoid to the myelo-megakaryocytoid in nature, in which three clonal evolutions were observed during the clinical course.     

骨髓增生异常综合征免疫表型分析

目的：探讨免疫表型测定在骨髓增生异常综合征（MDS）诊断及分型中的价值。方法：采用一组系列相关单克隆抗体和流式细胞术对19例MDS患者免疫表型进行检测，并对其中的10例进行了细胞遗传学检查。结果：MDS患者骨髓单个核细胞（MNC）CD13，CD33抗原表达率平均分别为36．69％和41．86％，而T淋巴系抗原CD3的表达平均仅为14．49％，且随着低危的难治性贫血（RA）向高危的难治笥贫血伴原始细胞增多（RAEB）或难治性贫血伴原始细胞增多－转变型（RAEB-t)的进展，较早期的髓系抗原CD13，CD33及干（祖）细胞抗原CD34的表达升高，并伴有T淋巴系抗原CD3的表达降低。10例进行了细胞遗传学检查的患者中，5例有染色体核型异常，染色体核型异常的患者与染色体核型正常的患者在抗原表达上存在区别。结论：对MDS患者进行免疫表型检查有助于MDS的诊断分型研究。     

Aplastic anaemia associated with a Philadelphia chromosome and monosomy 7 during immunosuppressive therapy

We describe a patient who presented with aplastic anaemia associated with the Philadelphia (Ph1) chromosome during immunosuppressive therapy and who subsequently developed myelodysplastic syndrome (MDS) with monosomy 7. Initially the patient had hypocellular fatty marrow without leukaemic blasts or dysplastic features. Chromosome analysis showed 46, XY, t(9;22)(q34;q11) during immunosuppressive therapy, but no leukaemic transformation was detected. The patient showed gradual haematologic improvement and became transfusion independent. Thereafter, bone marrow dysplasia with monosomy 7 progressed following transfusion independence. These findings indicate that multiple cytogenetic evolutions occur in aplastic anaemia during immunosuppressive therapy, and that Ph1 chromosome may play a role in bone marrow suppression rather than development of leukaemia.     

Interphase cytogenetic analysis of in vivo differentiation in the myelodysplasia of Down syndrome

In Down syndrome, acute megakaryoblastic leukemia (AMKL) occurs frequently during the first 4 years of life and is usually preceded by a period of myelodysplasia (MDS), often associated with chromosomal abnormalities. Archival peripheral blood and/or bone marrow films of six patients with Down syndrome and MDS whose leukemic cells contained monosomy 7 or trisomy 8 were studied to determine whether the abnormal precursors produce mature cells in vivo. Using fluorescence in situ hybridization (FISH) of interphase nuclei with chromosome-specific centromere probes for either chromosome 7 or 8, we were able to determine which cells had one, two, or three signals indicative of one, two, or three no. 7 or 8 chromosomes. In five patients with trisomy 8, 80% to 100% (94.5% +/- 6.2%) of the megakaryoblasts had three signals using a chromosome 8 probe; in one patient with monosomy 7, 96.5% of the megakaryoblasts had one signal using a chromosome 7 probe. In all six patients, the myeloid and lymphoid series did not have evidence of the chromosomal abnormality present in the blasts. In three of five patients with trisomy 8, three signals were observed in 27%, 33%, and 41% of normoblasts, respectively. These data are evidence that the abnormal cell in MDS is a progenitor cell with the potential of forming cells of megakaryocyte and erythroid lineages.     

Evidence for expression of early myeloid antigens in mature,non-blast myeloid cells in myelodysplasia

Myelodysplastic syndromes (MDS) are clonal hematopoietic stem cell disorders with frequent cytogenetic abnormalities. They can arise de novo or be related to therapy. Although blasts in MDS have been studied extensively, there is little information available on the mature, non-blast myeloid cells (NBMCs). We used a retrospective case-control study design. NBMC populations in MDS (48 cases) and in tumor-free control (12 cases) bone marrow samples were analyzed using multiparameter flow cytometry for mean side scatter (SSC) channel number and for expression of aberrant cell surface antigens. MDS cases were stratified on the basis of cytogenetic abnormalities. We report that NBMCs in MDS with normal karyotype expressed significantly higher HLA-DR than controls (P = 0.034). NBMCs in MDS cases with cytogenetic abnormalities and with > or =5% marrow blasts, compared with controls, had significantly higher CD34 and higher HLA-DR but lower CD10 and lower SSC mean channel number. CD34 expression in NBMCs was significantly greater in therapy-related MDS compared with de novo MDS ( P = 0.01), although the presence of cytogenetic abnormalities was not different ( P > 0.05). These data suggest that bone marrow, mature, NBMCs have phenotypic changes in MDS that are not seen in normal controls.     

Prolonged Bone Marrow Failure With Monosomy 7 After Engraftment Failure Following Bone Marrow Transplantation

A patient with acute myelogenous leukemia developed prolonged bone marrow failure along with the monosomy 7 chromosome abnormality. The patient had undergone bone marrow transplantation with CD34+ selection following induction failure. However, she then suffered engraftment failure and long-term pancytopenia. Her white blood cell count gradually increased with supportive therapy including granulocyte colony-stimulating factor (G-CSF), and chromosomal analysis of bone marrow cells revealed an abnormal karyotype. Thirty months after the bone marrow transplantation we observed monosomy 7 together with the existing chromosomal abnormality in the patient's bone marrow cells. It has been reported that some patients with idiopathic and posthepatitis aplastic anemia develop clonal disorders such as myelodysplastic syndrome/acute myelogenous leukemia with monosomy 7. The findings in our case suggest that the appearance of monosomy 7 in patients with aplastic anemia may be caused by prolonged low-level hematopoiesis, with or without G-CSF stimulation.     

Clonal analysis of myelodysplastic syndrome: monosomy 7 is expressed in the myeloid lineage, but not in the lymphoid lineage as detected by fluorescent in situ hybridization.

Conflicting results have been published on whether or not myelodysplastic syndromes (MDS) affect all cell lineages. Involvement of myeloid and erythroid cell lineages has been regularly observed, but it remains controversial whether the different lymphoid cell lineages are involved. In this study of eight patients with MDS associated with monosomy 7, fluorescent in situ hybridization (FISH) was used to enumerate the chromosomes 7 in interphase cells. With the probe D7Z1, the rate of false-positive detection of monosomy 7 was 3% +/- 2% in normal cells. T- and B-cell lines were established from eight patients with MDS and monosomy 7. As determined by FISH in interphase cells, 1.9% (0% to 3%) of the cells in the B-cell lines showed one fluorescent spot and 1.1% (0% to 2.9%) of the cells in the T-cell lines. These values do not differ from normal values. However, the possibility that normal cells were selected when the T- and B-cell lines were established could not be excluded. Therefore, peripheral blood cells were obtained, separated according to surface markers specific for lymphoid and myeloid cell lineage with a cell sorter, and analyzed for the expression of monosomy 7 by FISH. Antibodies recognizing T cells (CD3), B cells (CD20), natural killer (NK) cells (CD57), monocytes and granulocytes (low and high expression of CD11b antigen), and myeloid progenitors (CD33) were used to separate cells. The expression of monosomy 7 in the T cells, NK cells, and B cells did not differ from control values. These results in the lymphoid subpopulations are in stark contrast with the observations in the myeloid populations; the percentage of cells with monosomy 7 ranged from 9% to 78% (controls: 6% +/- 2%) in cells with low CD11b expression, 20% to 89% in cells with a high expression of the CD11b antigen (controls: 7% +/- 3%), and 23% to 91% in the CD33 positive cells (controls: 5% +/- 3%). The results of this study suggest that monosomy 7 does not usually affect lymphoid subpopulations but is restricted to committed progenitor cells with the capacity to differentiate into mature myeloid cells.     

Biphenotypic acute leukemia with Ph1 chromosome, M-BCR-, myeloperoxidase+, and CALLA+]

A 63 year-old woman was referred to our hospital because of fever and increased number of blasts in the bone marrow. On physical examination she had slight hepatomegaly but no splenomegaly. Laboratory tests disclosed a hemoglobin level of 8.5 g/dl; a WBC count of 13,200/microliter with 26% blasts; a platelet count of 51,000/microliter. A bone marrow aspirate was normocellular with 74% blasts and 37% blasts were stained positive for myeloperoxidase. Cell surface markers for HLA-DR, CD10, CD19, CD13, CD33 were positive. Karyotype analysis revealed 46, XX, t (9q+; 22q-) and 45XX, -7, t (9q+; 22q-). Southern analysis showed rearrangement of immunoglobulin heavy chain but not T cell receptor beta gene. Rearrangements in M-BCR were not detected with 5' or 3' bcr probes. After 2 courses of chemotherapy, blasts decreased to 7% with recovery of normal elements and 11 out of 20 metaphases of the bone marrow cells were normal karyotype. These findings suggest that this case was de novo Ph1 positive acute leukemia which demonstrated both lymphoid and myeloid features.     

Paroxysmal nocturnal hemoglobinuria clone in a case of myelodysplastic syndrome rapidly progressing to acute leukemia

Myelodysplastic syndrome (MDS) comprises a group of stem cell disorders with considerable clinical and morphological heterogeneity. We report a case of MDS in a middle-aged male with clinical features of sepsis, dysplastic neutrophils and 6% blasts on bone marrow aspirate. A clone of neutrophils with deficient expression of CD16, CD55 and CD59 was found. A diagnosis of MDS with excess blasts with co-existent paroxysmal nocturnal hemoglobinuria (PNH) was made. Within a fortnight, the patient progressed to acute myeloid leukemia. We are reporting this unusual case of MDS displaying a sizeable clone of dysplastic neutrophils deficient in glycosyl phosphatidyl inositol anchored proteins, highlighting a common origin of PNH and leukemic clone.     

Transient donor cell-derived myelodysplastic syndrome with monosomy 7 after unrelated cord blood transplantation

Donor cell leukaemia or myelodysplastic syndromes are extremely rare complications that have been observed not only after haematopoietic transplantation with progenitor cells harvested from bone marrow and peripheral blood, but also after cord blood transplantation. We describe the early onset of monosomy 7 in donor cells after cord blood transplantation in a patient diagnosed with myelodysplastic syndrome 3 months after transplantation. Fluorescent in situ hybridisation analysis performed in a cryopreserved aliquot of the cord blood showed 2.5% of nuclei with monosomy 7. The cord blood donor was studied and he showed neither peripheral blood cytopenias nor cytological or cytogenetic features of myelodysplasia. The cell blood counts (CBC) of the girl have improved over 2 yr while decreasing the percentage of monosomic cells. The monosomic clone has finally disappeared and the CBC are finally normal. This case of transient monosomy 7 started very early after engraftment emphasises the relevance of clonal instability of specific progenitor cells in the early engraftment, and host immune status, in cytogenetic abnormalities founded in donor cell-derived MDS and acute leukaemia. Moreover, the clinical follow-up of this patient, recommends a more conservative treatment for this clonal disease early developed after transplantation.     

Acute lymphoblastic leukaemia after bone marrow transplantation for aplastic anaemia

An 11.5-year-old girl developed acute lymphoblastic leukaemia 7 months after bone marrow transplantation for severe aplastic anaemia. Before transplantation there were neither morphologic nor cytogenetic abnormalities to suggest preleukaemia. The conditioning regimen consisted only of cyclophosphamide. At the time of development of acute lymphoblastic leukaemia, chromosome analysis showed the blasts to be of host origin with clonal abnormalities including monosomy 7. Such a preleukaemic syndrome presenting as severe aplastic anaemia is a very rare event (the case reported here is the only one of 436 patients in Seattle) and cannot be reliably excluded before transplantation.     

Identification of distinct prognostic subgroups in low- and intermediate-1-risk myelodysplastic syndromes by flow cytometry

The World Health Organization (WHO) classification contributes to refined classification and prognostication of myelodysplastic syndromes (MDSs). Flow cytometry might add significantly to diagnostic and prognostic criteria. Our analysis of bone marrow samples from 50 patients with MDS showed aberrant expression of differentiation antigens in the myelomonocytic lineage. This also accounted for refractory anemia (RA) with or without ringed sideroblasts (RS), indicating multilineage dysplasia. In 38% of patients, CD34(+) myeloid blasts expressed CD5, CD7, or CD56. Flow cytometry data were translated into a numerical MDS flow-score. Flow-scores increased significantly from RA with or without RS, refractory cytopenia with multilineage dysplasia (RCMD) with or without RS up to refractory anemia with excess of blasts-1 (RAEB-1) and RAEB-2. No significant differences were observed between WHO cytogenetic subgroups. Flow-scores were highly heterogeneous within International Prognostic Scoring System (IPSS) subgroups. Patients in progression to advanced MDS or acute myeloid leukemia had a significantly higher flow-score compared with non-transfusion-dependent patients. In 60% of patients with transfusion dependency or progressive disease, myeloid blasts expressed CD7 or CD56, in contrast to only 9% of non-transfusion-dependent patients. Moreover, all patients with pure RA with or without RS with aberrant myeloid blasts showed an adverse clinical course. In conclusion, flow cytometry in MDS identified aberrancies in the myelomonocytic lineage not otherwise determined by cytomorphology. In addition, flow cytometry identified patients at risk for transfusion dependency and/or progressive disease independent of known risk groups, which might have impact on treatment decisions and the prognostic scoring system in the near future.     

Multicenter prospective study of clonal complications in adult aplastic anemia patients following recombinant human granulocyte colony-stimulating factor (lenograstim) administration

To elucidate the relationship between treatment with granulocyte colony-stimulating factor (G-CSF) and the development of chromosomal abnormalities and clonal evolution in adult aplastic anemia (AA) patients, we performed a prospective multicenter study. Of the 104 registered patients, 91 were found by the central review committee to have the diagnosis of AA. Of the 91 patients, 84 were determined to be evaluable in this study and were treated with regimens including G-CSF (lenograstim). A time-course study (at registration and 6 and 12 months after registration) of G-banded chromosomes, fluorescence in situ hybridization (FISH) analysis for monosomy 7, and morphological assessment of bone marrow was performed with these patients during the 1-year follow-up period. G-banding analysis demonstrated the development of cytogenetic abnormalities in 10 (16.1%) of the 62 evaluable patients. The most common aberration was monosomy 7. FISH analysis demonstrated monosomy 7 in 7 (10.4%) of the 67 evaluable patients. Evolution into myelodysplastic syndrome (MDS) was observed in 5 (7.7%) of the 65 patients who underwent morphological assessment of bone marrow. All patients who developed cytogenetic abnormalities or MDS received immunosuppressive agents and/or steroids with G-CSF. This study demonstrated that some adult AA patients exhibit evolution into MDS and development of chromosomal abnormalities such as monosomy 7. Although the incidence seems to be comparable with that found in previous studies, further long-term follow-up will be necessary to confirm the relationship between G-CSF and the development of chromosomal abnormalities and MDS.     

骨髓增生异常综合征克隆性8号染色体三体和7号染色体缺失的发生及其临床意义

目的：了解＋8和-7／7q-克隆在骨髓增生异常综合征（MDS）中的发生情况，探讨＋8和-7／7q-克隆在MDS发生发展中的可能机制及其临床意义。方法：采用短期培养法和G显带技术，对MDS患者的染色体异常、尤其＋8和-7／7q～核型进行分析。结果：70例原发性MDS患者中，有43例存在染色体异常，异常检出率为61．4％，最常见的染色体异常为＋8（18例）和-7／7q-（8例），其中4例为＋8与-7／7q-并存。＋8克隆多出现在RA阶段，而-7／7q-克隆则出现在疾病进展中。伴有-7／7q-核型的MDS，更容易转化为白血病。结论：＋8和-7／7q-核型仍是MDS最为常见的染色体异常。＋8克隆出现在MDS的早期，可能与Fas介导的细胞凋亡有关；而-7／7q-克隆的形成，导致MDS的进展及向白血病转化，可能与丢失片段的抑癌基因的失活有关。     

SF3B1突变型骨髓增生异常综合征亚型发病机制及诊断

SF3B1基因突变形成了新骨髓增生异常综合征(MDS)亚型.MDS 国际预后工作组(international working group for the prognosis of myelodysplastic syndromes,IWG-PM)建议诊断标准:(1)血细胞减少;(2)SF3B1基因体细胞突变;(3)孤...     

Successful Bone Marrow Plus Cord Blood Stem Cell Transplantation in a Girl who Developed Myelodysplastic Syndrome from Hepatitis-associated Aplastic Anemia Treated with Long-term Immunosuppressants and Growth Factors

A 9-year-old girl who had hepatitis-associated aplastic anemia was treated intermittently with methylprednisolone pulse therapy and growth factors (granulocyte-colony stimulating factor (G-CSF), recombinant human erythropoietin (rhEpo) and cyclosporin A (CyA) for over two years. At this time, there was hematological improvement, but chromosome analysis revealed monosomy 7.

After six months, there was progression to myelodysplastic syndrome (MDS) (stage in refractory anemia of excess blasts (RAEB)) with monosomy 7, monosomy 6, marker chromosome and with hematological deterioration.

She received bone marrow (1.57×10⁵ cells kg^?1 (patient body weight)) plus cord blood cell (0.3×10⁷ cells kg^?1 (patient body weight)) transplantation from her brother, 2 years and 7 months after the diagnosis of hepatitis-associated aplastic anemia. Engraftment was achieved after two weeks, and acute graft-versus-host disease occurred in a mild form after four weeks. Hematological remission has been continuous for 20 months after bone marrow transplantation. Transformation of hepatitis-associated aplastic anemia to MDS with the monosomy 7, monosomy 6 and marker chromosome in this patient was considered to have been related to the administration of high doses of immunosuppressive drugs plus growth factors.