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.     

Molecular cytogenetic analysis of monosomy 7 in pediatric patients with myelodysplastic syndrome

Monosomy 7 is a non-random cytogenetic abnormality that is frequently associated with myelodysplastic syndromes (MDS). Twenty-four bone marrow samples from five pediatric patients with MDS were analysed using both traditional and Interphase cytogenetic analysis. The majority of the metaphases were monosomic for chromosome 7 while interphase cytogenetic analysis consistently detected a disomic cell population in nondividing cell populations. This suggests that the monosomy 7 cells have a distinct proliferative advantage compared to the disomic cell population. The results demonstrate that interphase cytogenetic analysis provides important cytogenetic information about non-dividing cell subpopulations, enhancing our understanding of the cell dynamics of normal and monosomy 7 cells in MDS.     

Clonal involvement of eosinophils in therapy-related myelodysplastic syndrome with eosinophilia, translocation t(1;7) and lung cancer

We report a therapy-related MDS (RAEB) patient with eosinophilia, unbalanced translocation der(7)t(1;7) (q12;q22) and lung cancer. We observed no increase in cytokine levels in serum or in the conditioned medium (CM) of peripheral T cells cultured with or without IL-2. When bone marrow (BM) cells were cultured with GM-CSF, IL-3 and SCF in a semisolid system, the colonies were exclusively eosinophilic. Cytogenetic analysis of the colony cells identified the same chromosome abnormality in all metaphases to that of BM cells. Suspension and clonogenic colony assay of BM cells cultured with various cytokines showed predominant eosinophilic growth and differentiation with GM-CSF, but not with the other cytokines examined. These findings, together with mild morphological abnormalities of eosinophils, indicate clonal involvement of eosinophils in the myelodysplastic syndrome (MDS) clone, and that the eosinophilia was derived from the neoplastic clone with the translocation and was not associated with the patient's lung cancer.     

Hypereosinophilia in a monosomy 7 myeloproliferative disorder in childhood

Hyperosinophilia in association with a monosomy 7 myeloproliferative disorder is described in an eight-year-old boy. Antileukemic treatment resulted in a decrease in the eosinophilia, but did not appear to affect the blast cell population or the presence of monosomy 7 cells in the bone marrow. These findings suggest that bone marrow karyotyping may be useful in differentiating pre-malignant causes of eosinophilia from those with a more benign etiology.     

Unbalanced translocation (1;7) in childhood myelodysplasia

We have identified an unusual pediatric patient among twelve patients with myelodysplasia and an unbalanced translocation involving chromosomes 1 and 7: -7, +der(1)t(1;7)(p11;p11). This 16-year-old male patient developed myelodysplasia and evolving acute leukemia, which were preceded by a 7-year history of marrow hypoplasia. The remaining patients were adults with clinical and hematologic findings similar to other reported cases with this chromosomal abnormality. The late appearance of this unbalanced clonal abnormality in this patient with marrow hypoplasia documents the importance of close cytogenetic follow-up of all patients with suspected bone marrow injury.     

Germ-line GATA2 p.THR354MET mutation in familial myelodysplastic syndrome with acquired monosomy 7 and ASXL1 mutation demonstrating rapid onset and poor survival

While most myelodysplastic syndrome/acute myeloid leukemia cases are sporadic, rare familial cases occur and provide some insight into leukemogenesis. The most clearly defined familial cases result from inherited mutations in RUNX1 or CEBPA. Recently, novel germline mutations in GATA2 have been reported. We, therefore, investigated individuals from families with one or more first-degree relatives with myelodysplastic syndrome/acute myeloid leukemia with wild-type RUNX1 and CEBPA, for GATA2 mutations. Screening for other recurrent mutations was also performed. A GATA2 p.Thr354Met mutation was observed in a pedigree in which 2 first-degree cousins developed high-risk myelodys-plastic syndrome with monosomy 7. They were also observed to have acquired identical somatic ASXL1 mutations and both died despite stem cell transplantation. These findings confirm that germline GATA2 mutations predispose to familial myelodysplastic syndrome/acute myeloid leukemia, and that monosomy 7 and ASXL1 mutations may be recurrent secondary genetic abnormalities triggering overt malignancy in these families.     

Spontaneous remission in myelodysplastic syndrome

 A 73-year-old man was admitted for investigation of pancytopenia. His physical examination was unremarkable and the bone marrow aspirate was compatible with myelodysplastic syndrome (RAEB). Cytogenetic analysis of the bone marrow revealed a trisomy 21. The patient received transfusions of packed red cells, and his condition remained stable for the next 7 months. He was then admitted with a chest infection and was treated with broad-spectrum antibiotics with satisfactory response. During his hospitalization there was a gradual increase in his complete blood count values, which persisted, resulting in a normal peripheral blood after 3 months. A bone marrow aspirate performed at that time revealed normal findings with no karyotypic abnormalities, indicating a spontaneous remission. The patient remained stable for the next 6 months; then he recurred with 20% blasts in his bone marrow and reappearance of trisomy 21in 42% of the metaphases examined. Several hematologic malignancies with spontaneous remissions have been described to date, but they have generally been short and recurrence is the rule, as in the case described. The role of endogenous cytokines in triggering these spontaneous remissions is under question, as the exact mechanism is unknown. Received: June 24, 1998 / Accepted: September 29, 1998     

Therapy-related myelodysplastic syndrome with monosomy 5 after successful treatment of acute myeloid leukemia (M2)

We describe a patient who developed myelodysplastic syndrome over 2 years after achieving complete remission of acute myeloid leukemia (AML). The patient was treated in July 1998 with anthracycline, etoposide, and behenoyl cytarabine chemotherapy for AML (French-American-British classification, M2; World Health Organization classification, AML with maturation) and achieved complete remission. At presentation, no chromosomal abnormalities were detected. In December 2000, the patient's peripheral blood revealed pancytopenia, and his bone marrow was hypocellular with trilineage myelodysplasia and no blasts. Chromosomal analysis revealed complex karyotypic abnormalities, including monosomy 5. The patient was diagnosed with high-grade myelodysplastic syndrome (MDS)/refractory anemia with excess blasts (RAEB) subtype. The pancytopenia progressed rapidly, and he died 2 months after the diagnosis of MDS. Therapy-related MDS and AML (t-MDS/t-AML) developing after treatment for acute leukemia is unusual; the primary leukemia associated with most cases of t-MDS/t-AML is acute promyelocytic leukemia (APL). This unusual case suggests that AML excluding APL should be considered a primary hematologic malignancy for t-MDS/t-AML.     

Hematopoietic stem cell and progenitor cell mechanisms in myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a group of disorders characterized by variable cytopenias and ineffective hematopoiesis. Hematopoietic stem cells (HSCs) and myeloid progenitors in MDS have not been extensively characterized. We transplanted purified human HSCs from MDS samples into immunodeficient mice and show that HSCs are the disease-initiating cells in MDS. We identify a recurrent loss of granulocyte-macrophage progenitors (GMPs) in the bone marrow of low risk MDS patients that can distinguish low risk MDS from clinical mimics, thus providing a simple diagnostic tool. The loss of GMPs is likely due to increased apoptosis and increased phagocytosis, the latter due to the up-regulation of cell surface calreticulin, a prophagocytic marker. Blocking calreticulin on low risk MDS myeloid progenitors rescues them from phagocytosis in vitro. However, in the high-risk refractory anemia with excess blasts (RAEB) stages of MDS, the GMP population is increased in frequency compared with normal, and myeloid progenitors evade phagocytosis due to up-regulation of CD47, an antiphagocytic marker. Blocking CD47 leads to the selective phagocytosis of this population. We propose that MDS HSCs compete with normal HSCs in the patients by increasing their frequency at the expense of normal hematopoiesis, that the loss of MDS myeloid progenitors by programmed cell death and programmed cell removal are, in part, responsible for the cytopenias, and that up-regulation of the “don’t eat me” signal CD47 on MDS myeloid progenitors is an important transition step leading from low risk MDS to high risk MDS and, possibly, to acute myeloid leukemia.     

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。     

Involvement of eosinophils in acute myeloid leukaemia with monosomy 7 demonstrated by fluorescence in situ hybridization

Summary. Monosomy 7 is the commonest monosomy in acute myeloid leukaemia (AML). A patient with AML and monosomy 7 was investigated by fluorescence in situ hybridization. Monosomy 7 could be demonstrated in the blasts and also in mature eosinophils, but apparently not in lymphocytes. Monosomy 7 may occur in a multipotential myeloid progenitor cell as part of the multi-step leukaemogenic process.     

Secondary acute myeloid leukaemia with monosomy 7 in identical adult twins

We report the development of secondary acute myeloid leukaemia (AML) with monosomy 7 in identical twins, both at the age of 52 years. In the first twin, induction therapy resulted in complete remission (CR). At relapse 9 months later monosomy 7 was found. The patient died of sepsis 11 months after diagnosis. The other twin presented with leucopenia and thrombocytopenia and refractory anaemia (RA) was diagnosed. During follow-up, fluorescence in situ hybridization analysis demonstrated a monosomy 7 in 11% of the cells. Twenty-eight months following diagnosis the patient progressed to RA with excess blasts in transformation and induction chemotherapy was initiated without achieving CR. Three months later an allogeneic stem cell transplantation from a niece was performed, resulting in CR of the secondary AML.     

Spontaneous remission of 2-chlorodeoxyadenosine (2-CdA)-related secondary myelodysplastic syndrome in a patient with refractory Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is sometimes resistant to conventional chemotherapies, and treatment with 2-chlorodeoxyadenosine (2-CdA) is gaining importance as a salvage treatment for refractory or recurrent LCH. Secondary malignancies such as acute myelogenous leukemia and myelodysplastic syndrome (MDS) due to 2-CdA have recently been reported. However, there have been no reports to date of cases of 2-CdA-related secondary MDS in which spontaneous remission was achieved. Here, we report the case of a 1-year-old boy with an occipital tumor who was diagnosed with LCH by biopsy and underwent chemotherapy. However, the disease relapsed and became refractory to chemotherapy. He received 2-CdA treatment, which was effective. However 6 months after the start of treatment, he developed MDS with chromosomal abnormality of 7q?. After 1-year observation without any intervention, his hematological findings had returned to normal, and the chromosomal abnormality had also disappeared. To our knowledge, this is the first report of 2-CdA-related MDS with spontaneous hematological remission.     

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.     

Monosomy 7 predisposes to diabetes insipidus in leukaemia and myelodysplastic syndrome

We studied the chromosomes in the bone marrow of 4 patients who had both diabetes insipidus (DI) and acute non-lymphocytic leukaemia. Clinical findings suggested that, in each case, myelodysplastic syndrome had preceded the onset of acute leukaemia. Two other such patients described in the literature had had a banded karyotype study of bone marrow cells. All 6 patients had deletions of chromosome 7. 3 had monosomy 7 as the sole cytogenetic abnormality, 2 had monosomy 7 associated with other clonal abnormalities and 1 had del(7)(q22) in association with other abnormalities. These data suggest that monosomy 7 or perhaps monosomy for 7q22-qter predisposes to DI. The mechanism by which the proposed predisposition is produced remains to be clarified.     

Prediction of therapy-related acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS) after autologous bone marrow transplant (ABMT) for lymphoma

Therapy-related acute myelogenous leukemia and myelodysplastic syndrome (t-AML/MDS) are being reported with increasing frequency as a complication of ABMT for Hodgkin's disease and non-Hodgkin's lymphoma. At present there is no method available to predict who is at risk or is destined to develop this nearly universally fatal disorder. We therefore investigated whether clonal growth of cells is predictive of the development of t-AML/MDS. In a patient who developed secondary AML/MDS 18 months after ABMT, X-linked clonality analysis at the human androgen receptor locus was performed on serial banked samples, and documented transition from polyclonal to clonal hematopoiesis. Clonal cells could be identified 6 months after transplant (1 year prior to the diagnosis of t-AML/MDS), at a time when there was no morphologic or clinical evidence of disease. Clonality analysis can be predictive of the development of t-AML/MDS after ABMT and may offer important insights into associated risk factors and strategies to minimize the risk of t-AML/MDS. Am. J. Hematol. 56:45–51, 1997. © 1997 Wiley-Liss, Inc.