Lymphoblastic transformation of myelodysplastic syndrome

Characterization of myelodysplastic syndromes progressing to acute lymphoblastic leukemia

Myelodysplastic syndromes (MDS) are a heterogeneous group of diseases, with a variable probability of transformation into acute leukemia, which is, in the vast majority of cases, of myeloid lineage. Nevertheless, rare cases of acute lymphoblastic leukemia in patients with previously diagnosed MDS have been reported. We describe a series of 3 cases of MDS/CMML marked with evolution to acute lymphoblastic leukemia (ALL) and provide a comprehensive review of the 49 cases documented in the literature so far. These sporadic events have only been published as single-case reports or small series to date. Such atypical cases emphasize the possibility of major phenotypic switches arising at the leukemic stem cell (LSC) and/or early progenitor levels, as a consequence of epigenetic and genomic events driving these changes in the bone marrow niche.

Acute pro-B-Cell lymphoblastic leukemia transformed from myelodysplastic syndrome with an ASXL1 missense mutation: A case report with literature review

The development of acute lymphoblastic leukemia (ALL) from myelodysplastic syndrome (MDS) is a very rare event. The current report presents a rare case of a 33-year-old man who was diagnosed with MDS with multiple-lineage dysplasia (MDS-MLD) that transformed into pro-B-ALL. A missense mutation (S1231F) of the additional sex combs like 1, transcriptional regulator gene was identified, which may have a substantial role in the progression, however does not act as an unfavorable prognostic marker. The patient died during induction chemotherapy. The present study further conducted an analysis on 30 patients to determine progression to ALL. Patients were predominantly male (76.7%, 23/30) with a median age of 56 years (3-90 years). The median time to transformation was 5.5 months (2-50 months). The most common type of MDS with ALL transformation comprised of MDS-excess blasts (MDS-EB; 40%, 12/30), MDS with single-lineage dysplasia (MDS-SLD; 30%, 9/30) and MDS with ring sideroblasts (MDS-RS; 16.7%, 5/30). The majority of the patients transformed to B-cell (66.7%, 16/24) followed by T-cell (33.3%, 8/24) ALL. From the 25 cases where data was available, the complete remission rate was 75% (15/20) with ALL-directed chemotherapy and the median remission duration was 15 months (range 4.5 to 51 months). However, the results indicated that ALL following MDS is characterized by a high rate of early death (20%, 5/25).

RARS with fibrosis and del(20q) transformed into ALL

Transformation of myelodysplastic syndrome (MDS) into acute myelogenous leukemia occurs in approximately 30 % of cases, while progression into acute lymphoblastic leukemia (ALL) is rare. We report on a 67-year-old man with the diagnosis of MDS, subtype refractory anemia with ring sideroblasts (RARS), karyotype 20q- , JAK-2 negative and grade III fibrosis on the bone marrow biopsy, who evolved into ALL 33 months after the diagnosis of MDS. RARS is one of the subtypes of MDS with most indolent course. Deletion of the long arm of chromosome 20 (20q-) is considered as good prognosis by the International Prognostic Scoring System, an important scoring system for predicting survival and evolution of MDS. Primary MDS with bone marrow fibrosis may represent a distinct clinicopathological and is supposed to have an unfavorable prognosis. The combined analysis of these features makes this rare report still more challenging and illustrates that biology of MDS is yet to be discovered.

Myelodysplastic syndrome with myelofibrosis transformed to a precursor B-cell acute lymphoblastic leukemia: a case report with review of the literature

Myelodysplastic syndromes (MDS) comprise a group of heterogeneous clonal hematopoietic cell disorders characterized by cytopenias, bone marrow hypercellularity, and increased risk of transformation to acute leukemias. MDS usually transformed to acute myeloid leukemia, and transformation to acute lymphoblastic leukemia (ALL) is rare. Herein, we report a unique patient who presented with MDS with myelofibrosis. Two months after the initial diagnosis, she progressed to a precursor B-cell acute lymphoblastic leukemia. She was treated with induction therapy followed by allogenic stem cell transplantation. She was alive and doing well upon last followup. We have also reviewed the literature and discussed the clinicopathologic features of 36 MDS patients who progressed to ALL reported in the literature.

Myelodysplastic syndrome associated with monosomy 7 in childhood: a retrospective study

Myelodysplastic syndrome (MDS) is a clonal hematopoietic stem cell disorder characterized by ineffective hematopoiesis, peripheral cytopenia, and dysplastic changes in the bone marrow. Monosomy 7 or partial loss of 7q is a common cytogenetic abnormality in MDS patients and is associated with poor prognosis. This study examined eight patients with monosomy 7 and MDS. Five MDS patients with monosomy 7 progressed to acute leukemia: three cases transformed into acute myelogenous leukemia (AML) in a mean time of only 4.6 months and two cases into acute lymphoblastic leukemia (ALL) in a mean time of 9 months. To our knowledge, this is the first report showing progression of monosomy 7 associated with MDS to ALL in the childhood period.

Progression of myelodysplasia to acute lymphoblastic leukaemia: implications for disease biology

Myelodysplastic syndrome (MDS) comprises a group of clonal haematopoietic disorders characterized by peripheral blood cytopenias, bone marrow hypercellularity, and abnormal blood cell differentiation. Approximately 30% of cases of MDS eventually progress to acute myelogenous leukemia (AML), while progression of MDS into acute lymphoblastic leukemia (ALL) is rare. In this report, we describe a case of MDS that progressed to ALL, and review the 21 previously reported cases of MDS to ALL transformation. We review the cancer stem cell model and its application to these disorders, and discuss the implications of the rarity of transformation of MDS to ALL for the biology of MDS and the pathogenesis of ALL.

Transformation of Myelodysplastic Syndrome to Acute Lymphoblastic Leukemia: A Case Report and Review of the Literature

Myelodysplastic syndrome (MDS) often transforms into acute leukemia, usually of a myeloid phenotype. However, the transformation of MDS into acute lymphoblastic leukemia (ALL) is extremely rare. We present a case of refractory anemia with excess of blasts (RAEB) that transformed into ALL. MDS (RAEB) was diagnosed in a 68-year-old Japanese woman in August 2001. Two months later, MDS progressed to erythroleukemia (French-American-British [FAB]classification, acute myeloid leukemia [AML]-M6), and in December, 2001, she was treated with combined chemotherapy containing aclarubicin, cytarabine, and granulocyte colony-stimulating factor, which improved her clinical symptoms. However, 1 month after the chemotherapy, she developed ALL. The blasts at that time had a markedly basophilic cytoplasm with multiple cytoplasmic vacuoles, and their morphology mimicked that of ALL-L3. The blasts also expressed CD13, a myeloid marker, in addition to lymphoid markers. Southern-blot analysis revealed rearrangement of the immunoglobulin heavy chain, but no additional chromosomal abnormality characteristic of ALL-L3 was detected. The patient was treated with chemotherapy, but she developed tumor lysis syndrome and died of multiple organ failure. Although the precise mechanism of lymphoid transformation is not yet fully understood, this case clinically supports the nature of MDS as a pluripotent hematopoietic stem cell disorder.

The myelodysplastic syndrome(s): a perspective and review highlighting current controversies

The myelodysplastic syndrome (MDS) includes a diverse group of clonal and potentially malignant bone marrow disorders characterized by ineffective and inadequate hematopoiesis. The presumed source of MDS is a genetically injured early marrow progenitor cell or pluripotential hematopoietic stem cell. The blood dyscrasias that fall under the broad diagnostic rubric of MDS appear to be quite heterogeneous, which has made it very difficult to construct a coherent, universally applicable MDS classification scheme. A recent re-classification proposal sponsored by the World Health Organization (WHO) has engendered considerable controversy. Although the precise incidence of MDS is uncertain, it has become clear that MDS is at least as common as acute myelogenous leukemia (AML). There is considerable overlap between these two conditions, and the former often segues into the latter; indeed, the distinction between AML and MDS can be murky, and some have argued that the current definitions are arbitrary. Despite the discovery of several tantalizing pathophysiological clues, the basic biology of MDS is incompletely understood. Treatment at present is generally frustrating and ineffective, and except for the small subset of patients who exhibit mild marrow dysfunction and low-risk cytogenetic lesions, the overall prognosis remains rather grim. In this narrative review, we highlight recent developments and controversies within the context of current knowledge about this mysterious and fascinating cluster of bone marrow failure states.

Patients with high-risk myelodysplastic syndrome can have polyclonal or clonal haemopoiesis in complete haematological remission

The clonality of mature peripheral blood-derived myeloid and lymphoid cells and bone marrow haemopoietic progenitors from 18 females with myelodysplasia (MDS) (five refractory anaemia, RA; one RA with ringed sideroblasts, RARS; three chronic myelomonocytic leukaemia, CMML; four RA with excess of blasts, RAEB; five RAEB in transformation, RAEB-t) was studied by X-chromosome inactivation analysis. Using the human androgen-receptor (HUMARA) assay, we analysed the clonal patterns of highly purified immature CD34+ 38- and committed CD34+ 38+ marrow-derived progenitors, and CD16+ 14- granulocytes, CD14+ monocytes, CD3+ T and CD19+ B lymphocytes from peripheral blood. In high-risk patients (RAEB, RAEB-t), clonality analysis was performed before and after intensive remission-induction treatment. All patients, except one with RA, had predominance of a single clone in their granulocytes and monocytes. The same clonal pattern was found in CD34+ progenitor cells. In contrast, CD3+ T lymphocytes were polyclonal or oligoclonal in 14/18 patients. X-chromosome inactivation patterns of CD19+ B cells were highly concordant with CD3+ T cells except for two patients (one RA, one CMML) with monoclonal B and polyclonal T lymphocytes, therefore suggesting a clonal mutation in a progenitor common to the myeloid and B-lymphoid lineages or the coexistence of MDS and a B-cell disorder in these particular patients. After high-dose non-myeloablative chemotherapy, polyclonal haemopoiesis was reinstalled in the mature myeloid cells and immature and committed marrow progenitors in three of four patients achieving complete haematological remission. Therefore we conclude that most haematological remissions in MDS are associated with restoration of polyclonal haemopoiesis.

Lymphoblastic transformation of myelodysplastic syndrome

Mielodysplastic syndromes (MDS) are clonal disorders of the hemopoietic stem cell. About one third of the cases terminate in an acute leukemia, usually acute myeloblastic leukemia. However, few cases of transformation into acute lymphoblastic leukemia (ALL) have been described. We present a case of refractory anemia that transformed into ALL two months after diagnosis and was successfully treated with conventional chemotherapy. Two years later a hyperfibrotic form of MDS was detected in the patient, that soon after terminated in acute megakaryoblastic leukemia. The course of MDS in the present case provides evidence that MDS can involve a pluripotent stem cell, presenting clonal evolution, documented by successive changes in its clinical and hematological features.

Lymphoblastic transformation of chronic myelomonocytic leukemia in an infant

A 10-month-old infant with chronic myelomonocytic leukemia (CMML) of 5 months' duration, who had been treated only with transfusion, displayed leukemic transformation characterized by lymphoid morphology, PAS positivity, and myeloperoxidase negativity. Surface marker analysis of blast cells revealed expression of lymphoid-associated antigens (CD10 and CD19) but not myeloid-associated antigens (CD13, CD14, and CD33). These findings suggest that some cases of infantile CMML are clonal disorders arising in a pluripotent stem cell that can also differentiate along the lymphoid cell lineage.

Acute leukemic transformation of myelodysplastic syndrome--immunophenotypic, genotypic, and cytogenetic studies

The clinical and biological characteristics of myelodysplastic syndrome (MDS) in acute leukemic transformation were studied in 23 patients. All had myeloid transformation according to FAB criteria, but coexpression of lymphoid-associated antigens was detected in five of the 20 patients who underwent an immunophenotypic study. Rearrangement of the immunoglobulin heavy chain gene was also observed in one of the five patients who coexpressed lymphoid markers and that of the T-cell receptor beta chain gene in another one. None had pure lymphoid transformation. Clonal chromosomal abnormalities were noted in 12 (63%) of the 19 patients who underwent cytogenetic study, most commonly - 7 (six patients or 32%). In the 18 patients who underwent serial analyses both at MDS diagnosis and at acute transformation, seven (39%) underwent karyotypic evolution. The most common new or additional aberrations were +8 and +21. N-ras gene mutation was detected in two of the nine patients at acute leukemic transformation. The median interval from diagnosis of MDS to onset of acute transformation was 10 months (1-36 months). Patients with a normal karyotype at diagnosis had a significantly longer chronic phase duration than those with chromosomal abnormalities (median of 20 months vs. 5 months). However, all had a short survival time after diagnosis of acute leukemia, whether chromosomal anomalies were present or not.

Transformation of chronic myelomonocytic leukemia to acute lymphoblastic leukemia: case report and review of the literature of lymphoblastic transformation of myelodysplastic syndrome

If chronic myelomonocytic leukemia (CMML) transforms into an acute leukemic phase, the blast crisis is invariably myeloid. Occasionally, the other subtypes of myelodysplastic syndrome (MDS) (refractory anemia, refractory anemia with ringed sideroblasts, refractory anemia with excess blasts, refractory anemia with excess blasts in transformation) have been noted to transform into acute lymphoblastic leukemia (ALL). We now report a case of CMML that transformed into ALL and we review the literature of 13 other cases of MDS with ALL transformation. Such cases provide suggestive clinical evidence that MDS can involve a pluripotent stem cell.

Acute lymphoid leukemias following either a previous chronic myelogenous leukemia or myelodysplastic syndrome: phenotypic and genomic differences

We have analyzed the immunological and genomic characteristics of the lymphoid blast cells present in secondary lymphoid leukemias following either a previous chronic myelogenous leukemia (CML) or myelodysplastic syndrome (MDS). Twenty-one of 107 secondary leukemias analyzed displayed a lymphoid phenotype (15 after a CML and 6 after a MDS). Most of the lymphoid blast crises of CML (73%) correspond to pure lymphoid transformation, all of them having a common acute lymphoblastic leukemia (ALL) phenotype (CD10+). By contrast, in all MDS cases, lymphoid blast cells coexisted with another myeloid component (hybrid leukemias) and showed an early B phenotype. IgH and TCR-gamma gene rearrangements were detected in the CML-lymphoid blast crisis (86% of cases) more frequently than in the MDS transformations (33%). The TCR-beta gene was in germ line configuration in all cases while TCR-delta gene rearrangements were detected in four cases, all of them corresponding to a previous diagnosis of CML. These results show the existence of both immunophenotypic and genomic differences between the lymphoid transformations of either CML or MDS, which could reflect differences at the stage of maturation of the target cell in these transformations.

Karyotypic analysis in primary myelodysplastic syndromes

Cytogenetics has provided new insights into the biology and pathogenesis of myelodysplastic syndromes. In patients with refractory anemia, it has provided proof of clonality and has helped differentiate chronic myelomonocytic leukemia from chronic myeloid leukemia. As a prognostic tool, cytogenetics has been predictive of duration of survival and leukemic transformation. However, its role as an independent prognostic factor compared with recent prognostic scoring systems remains to be determined. New techniques such as fluorescent in situ hybridization using chromosome-specific DNA probes may expand the usefulness of cytogenetics. The prognostic impact of cytogenetics may not be fully realized until more effective treatments become available.

Myelodysplastic syndromes. Pathogenesis, diagnosis and treatment

Our understanding of the biology of leukemia and myelodysplasia is still only partial. The diagnosis of myelodysplasia is often based on quantitative and qualitative findings in the peripheral blood and bone marrow. These findings are often shared by other disorders. There is a need for sensitive and inexpensive laboratory tests to determine clonality and karyotypic abnormalities in this disorder. Future classifications of these syndromes will need to be based on morphologic and biologic markers that are closely linked to disease progression, response to treatment, and survival. Our limited understanding of the pathogenesis of MDS decreases the specificity and effectiveness of our therapeutic interventions. Agents that are minimally toxic such as CRA, danazol, 1,25-dihydroxyvitamin D3, androgens, and pyridoxine are seldom useful. Antileukemic therapy and allogeneic bone marrow transplantation have a major role to play in patients younger than 45 years of age; in older patients these treatment modalities remain controversial because of their toxicity. Hematopoietic growth factors, used alone or in combination, may improve the quality of life and improve survival of patients with MDS. Growth factors may also decrease treatment-related mortality associated with chemotherapy and bone marrow transplantation and render these treatment modalities available for a higher percentage of patients. The development of more specific differentiating agents may permit hematopoietic differentiation while minimizing side effects.

Bone marrow analysis of the myelodysplastic syndromes: histological and immunohistochemical features related to the evolution of overt leukemia

Bone marrow trephines from 31 patients with an initial diagnosis of myelodysplastic syndromes (MDS) were examined and analyzed histologically and immunohistochemically. In those cases terminating in overt leukemia (6/31, 19%), the number of bone marrow mast cells was significantly reduced, compared with those which did not evolve to overt leukemia. The bone marrow lymphoid cells that may participate in immunosurveillance against the proliferation of blast cells were also significantly reduced in cases terminating in overt leukemia. However, S-100 protein-positive cells, which include histiocytes and suppressor T-cells, were increased in cases terminating in overt leukemia. The results indicated that examination of the bone marrow to determine the proportions of mast cells and lymphoid cells which may be involved in host defense systems may be useful in predicting the evolution to overt leukemia in MDS. In the present series, patients with a hypocellular marrow (5/31, 16%) did not progress to overt leukemia and had a significantly lower bone marrow reticulin content, a significantly lower megakaryocyte count, a relatively higher mast cell count and a significantly higher lymphoid cell count than those with a normocellular or hypercellular marrow. These findings may reflect the initial features of MDS or, possibly, that hypocellular MDS is an independent entity with a low potential for blastic proliferation.

Absence of immunoglobulin and T-cell receptor gene rearrangements in myelodysplastic syndromes and acute nonlymphocytic leukemias

The arrangement of the immunoglobulin and T-cell receptor genes has been analysed in 72 cases of primary myelodysplastic syndrome and 17 cases of acute nonlymphocytic leukemia. DNA was extracted from bone marrow aspirates, digested with at least two restriction enzymes, and hybridised with probes for the joining region of the immunoglobulin heavy chain gene, the constant region of the T-cell receptor beta chain gene, and the joining region of the T-cell receptor gamma chain gene. All cases showed germline arrangements of the immunoglobulin and the T cell receptor genes. Thus, true interlineage infidelity, myeloid to lymphoid, is a rare occurrence in myelodysplasia and in myeloid leukemias.

Simultaneous expression of lymphoid and myeloid phenotypes in acute leukemia arising from myelodysplastic syndrome

A 57-year-old female developed myelodysplastic syndrome (MDS) that terminated as a biphenotypic leukemia after exposure to chemoradiotherapy. Double staining of blast cells, using monoclonal antibodies specific for myeloid and lymphoid lineage, demonstrated that one-third of the leukemic cells simultaneously expressed the E rosette-associated antigen (OKT11) and myeloid-associated antigen (MY7). This finding suggests the possibility that some cases of MDS are clonal disorders that arise in a pluripotent stem cell that can also differentiate to T cell lineage.