Morphology and Classification of Myelodysplastic Syndromes

Normal platelet counts mask abnormal thrombopoiesis in patients with chronic myeloid leukemia

Increased platelet heterogeneity has been reported in myeloproliferative neoplasms (MPN) with thrombocytosis. However, whether abnormal thrombopoiesis occurs in patients with chronic myeloid leukemia (CML) who have normal platelet counts, remains unclear. In order to explore this question, 25 patients with CML with normal platelet counts (CML-N), 40 patients with CML with elevated platelet counts (CML-E) and 33 healthy adults were recruited. The association of platelet count with mean platelet volume (MPV), platelet large cell ratio (P-LCR) and platelet distribution width (PDW) was examined. Bone marrow smears were also reviewed to assess the proliferation and abnormal lobation of megakaryocytes. The results showed that the two CML groups exhibited higher MPV, P-LCR and PDW values than those of the controls (P<0.05). Furthermore, the CML-N group was more heterogeneous in terms of thrombopoiesis than the CML-E group, as demonstrated by a higher PDW (P<0.05) and higher ratio of multinucleated dysmegakaryocytes (12.17 vs. 4.69%; χ²=29.79; P=0.000). In addition, no correlation between platelet count and MPV, P-LCR or PDW was observed in the CML-N group (r=-0.102, -0.051 and -0.049, and P=0.619, 0.828 and 0.810, respectively). The results suggested that patients in the CML-N group have more heterogeneous thrombopoiesis of megakaryocytes and platelets, and that apparently normal platelet counts may mask the abnormal thrombopoiesis in these patients.

Phase 1 multicenter dose-escalation study of ezatiostat hydrochloride (TLK199 tablets), a novel glutathione analog prodrug, in patients with myelodysplastic syndrome

Phase 1 testing of ezatiostat, a glutathione S-transferase P1-1 inhibitor, for the treatment of myelodysplastic syndrome was conducted in a multidose-escalation study. Patients received 10 dose levels (200, 400, 1000, 1400, 2000, 2400, 3000, 4000, 5000, and 6000 mg) of ezatiostat tablets in divided doses on days 1 to 7 of a 21-day cycle for a maximum of 8 cycles. The safety and pharmacokinetics of ezatiostat were evaluated. Forty-five patients with low to intermediate-2 International Prognostic Scoring System risk myelodysplastic syndrome were enrolled. No dose-limiting toxicities were observed. The most common grade 1 or 2, respectively, treatment-related adverse events were nonhematologic: nausea (56%, 9%), diarrhea (36%, 7%), vomiting (24%, 7%), abdominal pain (9%, 0%), constipation (4%, 9%), anorexia (3%, 7%), and dyspepsia (3%, 7%). Concentration of the primary active metabolite, TLK236, increased proportionate to ezatiostat dosage. Seventeen hematologic improvement (HI) responses by International Working Group criteria were observed at dose levels of 200 to 6000 mg/day with 11 HI responses at doses of 4000 to 6000 mg/day. HI responses occurred in all lineages including 3 bilineage and 1 complete cytogenetic response. Decreased number of red blood cell and platelet transfusions and in some cases transfusion independence were attained. Extended dose schedules of ezatiostat tablets are under investigation. This study was registered at http://www.clinicaltrials.gov as NCT00280631.

Phase 1-2a multicenter dose-escalation study of ezatiostat hydrochloride liposomes for injection (Telintra, TLK199), a novel glutathione analog prodrug in patients with myelodysplastic syndrome

BACKGROUND

Ezatiostat hydrochloride liposomes for injection, a glutathione S-transferase P1-1 inhibitor, was evaluated in myelodysplastic syndrome (MDS). The objectives were to determine the safety, pharmacokinetics, and hematologic improvement (HI) rate. Phase 1-2a testing of ezatiostat for the treatment of MDS was conducted in a multidose-escalation, multicenter study. Phase 1 patients received ezatiostat at 5 dose levels (50, 100, 200, 400 and 600 mg/m2) intravenously (IV) on days 1 to 5 of a 14-day cycle until MDS progression or unacceptable toxicity. In phase 2, ezatiostat was administered on 2 dose schedules: 600 mg/m2 IV on days 1 to 5 or days 1 to 3 of a 21-day treatment cycle.

RESULTS

54 patients with histologically confirmed MDS were enrolled. The most common adverse events were grade 1 or 2, respectively, chills (11%, 9%), back pain (15%, 2%), flushing (19%, 0%), nausea (15%, 0%), bone pain (6%, 6%), fatigue (0%, 13%), extremity pain (7%, 4%), dyspnea (9%, 4%), and diarrhea (7%, 4%) related to acute infusional hypersensitivity reactions. The concentration of the primary active metabolites increased proportionate to ezatiostat dosage. Trilineage responses were observed in 4 of 16 patients (25%) with trilineage cytopenia. Hematologic Improvement-Erythroid (HI-E) was observed in 9 of 38 patients (24%), HI-Neutrophil in 11 of 26 patients (42%) and HI-Platelet in 12 of 24 patients (50%). These responses were accompanied by improvement in clinical symptoms and reductions in transfusion requirements. Improvement in bone marrow maturation and cellularity was also observed.

CONCLUSION

Phase 2 studies of ezatiostat hydrochloride liposomes for injection in MDS are supported by the tolerability and HI responses observed. An oral formulation of ezatiostat hydrochloride tablets is also in phase 2 clinical development.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT00035867.

Reactive oxygen species, DNA damage, and error-prone repair: a model for genomic instability with progression in myeloid leukemia?

Myelodysplastic syndromes (MDS) comprise a heterogeneous group of disorders characterized by ineffective hematopoiesis, with an increased propensity to develop acute myelogenous leukemia (AML). The molecular basis for MDS progression is unknown, but a key element in MDS disease progression is loss of chromosomal material (genomic instability). Using our two-step mouse model for myeloid leukemic disease progression involving overexpression of human mutant NRAS and BCL2 genes, we show that there is a stepwise increase in the frequency of DNA damage leading to an increased frequency of error-prone repair of double-strand breaks (DSB) by nonhomologous end-joining. There is a concomitant increase in reactive oxygen species (ROS) in these transgenic mice with disease progression. Importantly, RAC1, an essential component of the ROS-producing NADPH oxidase, is downstream of RAS, and we show that ROS production in NRAS/BCL2 mice is in part dependent on RAC1 activity. DNA damage and error-prone repair can be decreased or reversed in vivo by N-acetyl cysteine antioxidant treatment. Our data link gene abnormalities to constitutive DNA damage and increased DSB repair errors in vivo and provide a mechanism for an increase in the error rate of DNA repair with MDS disease progression. These data suggest treatment strategies that target RAS/RAC pathways and ROS production in human MDS/AML.

Transformation of childhood MDS-refractory anemia to acute lymphoblastic leukemia

Myelodysplastic syndromes (MDS) are clonal disorders of hematopoietic stem cell. Patients have a deteriorating course with about 30% evolving into acute leukemias usually of the myeloid phenotype. Evolution into acute lymphoblastic leukemia is a rare and intriguing phenomenon seen in far less than 1% of adult cases, and extremely rare in pediatric population. We report a case of childhood MDS-refractory anemia transforming into acute lymphoblastic leukemia after an interval of 21 months since presentation and being on cyclosporine therapy for 9.5 months. The case raises further questions about the biology of MDS and the potential role of cyclosporine in leukemic transformation.

New insights into the physiology and treatment of acquired myelodysplastic syndromes and aplastic pancytopenia

MDS are a diverse group of primary and secondary bone marrow disorders that are characterized by cytopenias in blood, prominent dysplastic features in blood or bone marrow, and normal or hypercellular bone marrow. MDS in cats are typically associated with FeLV infection. Dogs with MDS-RC and MDS-Er seem to respond to erythropoietin administration and have prolonged survival. Dogs with MDS-EB respond poorly to present treatments, and survival is short. Prognosis and probability of progression to acute myelogenous leukemia can be predicted based on the percentage of myeloblasts in bone marrow. Several experimental therapeutic modalities in human beings have been described that may be useful in treating MDS-EB in dogs and cats. Aplastic pancytopenia is a relatively rare disorder in dogs and cats. Causes include Ehrlichia spp, Parvovirus, and FeLV infections; sepsis; chronic renal failure; drug and toxin exposure; and idiopathic causes. Diagnosis is based on identification of multiple cytopenias in the blood and hypoplastic/aplastic bone marrow, with the marrow space replaced by adipose tissue. Treatment and outcome are dependent on determining the underlying cause of the bone marrow failure.

Acute myeloid leukemia and myelodysplastic syndrome after doxorubicin-cyclophosphamide adjuvant therapy for operable breast cancer: the National Surgical Adjuvant Breast and Bowel Project Experience

PURPOSE

We reviewed data from all adjuvant NSABP breast cancer trials that tested regimens containing both doxorubicin (A) and cyclophosphamide (C) to characterize the incidence of subsequent acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS).

MATERIALS AND METHODS

Six complete NSABP trials have investigated AC regimens (B-15, B-16, B-18, B-22, B-23, and B-25). Six distinct AC regimens have been tested and are distinguished by differences in cyclophosphamide intensity and cumulative dose and by the presence or absence of mandated prophylactic support with growth factor and ciprofloxacin. In all regimens, A was given at 60 mg/m(2) q 21 days x 4. C was given as follows: 600 mg/m(2) q 21 days x 4 ("standard AC"); 1,200 mg(2) q 21 days x 2; 1,200 mg/m(2) q 21 days x 4; 2,400 mg/m(2) q 21 days x 2; and 2,400 mg/m(2) q 21 days x 4. Occurrence of AML/MDS was summarized by incidence per 1,000 patient-years at risk and by cumulative incidence. Rates were compared across regimens, by age, and by treatment with or without breast radiotherapy.

RESULTS

The incidence of AML/MDS was sharply elevated in the more intense regimens. In patients receiving two or four cycles of C at 2,400 mg/m(2) with granulocyte colony-stimulating factor (G-CSF) support, cumulative incidence of AML/MDS at 5 years was 1.01% (95% confidence interval [CI], 0.63% to 1.62%), compared with 0.21% (95% CI, 0.11% to 0.41%) for patients treated with standard AC. Patients who received breast radiotherapy experienced more secondary AML/MDS than those who did not (RR = 2.38, P=.006), and the data indicated that G-CSF does may possibly also be independently correlated with increased risk.

CONCLUSION

AC regimens employing intensified doses of cyclophosphamide requiring G-CSF support were characterized by increased rates of subsequent AML/MDS, although the incidence of AML/MDS was small relative to that of breast cancer relapse. Breast radiotherapy appeared to be associated with an increased risk of AML/MDS.

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.

Human deep tissue infection with an entomopathogenic Beauveria species

Beauveria spp. are ubiquitous fungal entomopathogens that are commercially distributed as biological insecticides worldwide. In this paper we describe the clinical manifestation, diagnosis, and therapy of the first documented human deep tissue infection with an entomopathogenic Beauveria species in a patient receiving immunosuppressive therapy and describe the morphological and molecular characterization of the mold.

Cytologic evaluation of primary and secondary myelodysplastic syndromes in the dog

Myelodysplastic syndromes are a heterogeneous group of acquired primary and secondary alterations of hematopoietic stem cells that result in cytopenias in blood and cytologic features of dysplasia in blood and/or bone marrow. To better understand the cytologic features that would permit differentiation of primary and secondary forms of myelodysplasia, we reviewed 267 consecutive bone marrow reports from dogs. These reports indicated that 34 dogs (12.7%) had dysgranulopoiesis, dyserythropoiesis, and/or dysthrombopoiesis in >10% of granulopoietic cells, erythroid cells, and/or megakaryocytes, respectively. Thirteen dogs had primary myelodysplastic syndromes, and 21 had secondary myelodysplastic syndromes. Of the 13 dogs with primary myelodysplasia, 4 were subclassified as myelodysplastic syndrome with refractory anemia (MDS-RA), and 9 were subclassified as myelodysplastic syndrome with excess blasts (MDS-EB). Secondary conditions associated with dysplasia in the bone marrow included malignant lymphoma (n = 5), myelofibrosis (n = 3), immune-mediated thrombocytopenia (n = 4), immune-mediated hemolytic anemia (n = 5), multiple myeloma with melphalan administration (n = 1), pyometra with estrogen administration (n = 1), polycythemia vera (n = 1), and thrombopathia (n = 1). MDS-RA was characterized by <5% myeloblasts in bone marrow, normal granulocyte maturation ratio, increased erythroid maturation ratio, and dysplastic changes in >15% of erythroid cells. MSD-EB was characterized by >/=5% myeloblasts in bone marrow, high granulocyte maturation and erythroid maturation ratios, >/=32% dysplastic granulocytes, and the presence of small atypical immature myeloid cells. Secondary myelodysplastic syndromes were characterized by <5% myeloblasts in bone marrow, variable granulocyte maturation and erythroid maturation ratios, and variable dysplastic features. These results indicate that morphology alone cannot be used to distinguish primary and secondary myelodysplastic syndromes in dogs.

p53 protein overexpression in bone marrow biopsies of patients with Shwachman-Diamond syndrome has a prevalence similar to that of patients with refractory anemia

CONTEXT

Shwachman-Diamond syndrome (SDS) is a rare inherited disorder characterized by pancreatic insufficiency, neutropenia, and in some patients, metaphyseal dysostosis. Patients with SDS are at a high risk for development of bone marrow failure, myelodysplastic syndrome, and acute leukemia. The p53 gene plays a major role in cell-cycle regulation, particularly in the presence of a genetic alteration in DNA, a critical step for the initiation of leukemogenesis. p53 gene up-regulation and p53 protein overexpression may occur as a cellular reaction to significant DNA damage. Shwachman-Diamond syndrome and refractory anemia patients have close similarities in the prevalence of acute leukemia and in cell-cycle changes in bone marrow cells. This similarity was further investigated for p53 protein overexpression using archived tissue from patients with hematologic diseases having various leukemic propensities, including SDS and refractory anemia.

METHODS

Immunohistochemical staining for p53 protein overexpression was performed on bone marrow biopsies from 9 patients with SDS. These specimens were compared with biopsies from 71 patients with acquired hematologic disorders with variable risk levels for leukemia, including acquired aplastic anemia (n = 14), refractory anemia (n = 46), and various acquired cytopenias (n = 11), as well as 37 control subjects.

RESULTS

p53 protein overexpression was identified only in patients with SDS and in patients with refractory anemia; these groups exhibited comparable prevalences of 78% and 72%, respectively. None of the patients with acquired aplastic anemia, acquired cytopenias, or in the control group showed overexpression of p53 protein.

CONCLUSION

The prevalence of p53 protein overexpression in SDS is significantly different from that in acquired aplastic anemia and acquired cytopenias, but it is similar to the prevalence in refractory anemia. We speculate that p53 protein overexpression in this bone marrow failure syndrome may represent an early indicator of significant DNA genetic alteration, which is a crucial step in the process of leukemogenesis.

Successful electroconvulsive therapy in an elderly man with severe thrombocytopenia: case report and literature review

Electroconvulsive therapy (ECT) is a safe and effective treatment for depression. Furthermore, modifications to ECT have made it a safe procedure for patients who were previously thought to be too ill or old to undergo the stress of convulsions. Little is known, however, of the safety of performing ECT on patients with severe thrombocytopenia. Such patients may be at increased risk for hemorrhagic complications due to the procedure. In this article, we describe the case of a 74-year-old man with major depression and myelodysplastic syndrome with associated severe thrombocytopenia, who underwent successful administration of a full course (nine treatments) of ECT. The physiologic changes caused by modified ECT and the potential risk of hemorrhage (including intracranial hemorrhage) in thrombocytopenic patients undergoing ECT are also discussed.

Amifostine alone and in combination with erythropoietin for the treatment of favorable myelodysplastic syndrome

Ten anemic patients with favorable myelodysplastic syndrome (MDS) were first treated with two 5-week courses of amifostine alone (each course consisted of 200 mg/m(2) of the drug given intravenously three times a week for 3 weeks), followed by an additional two courses combined with subcutaneous erythropoietin (EPO) (150 U/kg, three times a week for 8 weeks). The study patients either had previously failed to respond to treatment with EPO or had pretreatment serum EPO levels of more than 100 mU/ml. None of the patients experienced a complete or partial response in anemia or other cytopenias. We conclude that amifostine alone or in combination with EPO has limited therapeutic activity in MDS.

Erythroid defects and increased retrovirally-induced tumor formation in Evi1 transgenic mice

Aberrant expression of the Evi1 (ecotropic virus integration site 1) proto-oncogene has been associated with hematopoietic malignancies in both mice and man. To determine the effect of enforced expression of Evi1 in vivo, we developed a transgenic mouse model utilizing the murine Sca-1 (Ly-6E.1) promoter. Here, we describe the generation and analysis of three independent lines of Evi1 transgenic mice. Transgenic animals of two founder lines developed normally. These mice did not show any obvious hematological abnormalities but showed a significant reduction in the number of bone marrow colony-forming unit erythroid (CFU-E)-derived colonies. This implies a defect of normal erythroid hematopoiesis affecting relatively late erythroid progenitor cells. We also show that when newborn Evi1 transgenic mice of these two lines were infected with Cas-Br-M MuLV, tumor incidence was greatly enhanced in comparison with nontransgenic littermates, indicating an increased susceptibility for leukemia development. Interestingly, analysis of a third founder line revealed that all male progeny consistently displayed severely impaired erythropoiesis with major defects in the bone marrow, spleen and peripheral blood. Taken together, our results present the first evidence of Evi1 disturbing normal erythropoiesis in vivo and provides evidence for cooperative potential of Evi1 in tumor progression.

Cytokine therapy for myelodysplastic syndrome

The myelodysplastic syndromes are a heterogeneous family of hematologic disorders characterized by ineffective hematopoiesis. Because of the interpatient variability regarding prognosis and morbidity, management of myelodysplastic syndromes continues to be a challenge to clinical hematologists. Pancytopenia and defective function of neutrophils and platelets carry a high risk of infectious or hemorrhagic complications. Erythropoietin is perhaps the most commonly used therapeutic option, second only to transfusion; improvement of erythropoiesis is seen in approximately 20% of patients, mainly in those with relatively preserved erythroid function and no or low transfusion requirements. Coadministration of erythropoietin with either granulocyte colony-stimulating factor or granulocyte-macrophage colony-stimulating factor may increase the response rate up to 50%. Although prophylactic administration of granulocyte- or granulocyte-macrophage colony-stimulating factor cannot be recommended, treatment of febrile neutropenia might benefit from administration of granulocyte- or granulocyte-macrophage colony-stimulating factor in addition to antibiotics.

Ultrastructural observations on bone marrow cells of 26 patients with myelodysplastic syndromes

Bone marrow aspirates from 26 patients with myelodysplastic syndrome (MDS) were examined using transmission electron microscopy. The red blood cell precursors in 9 patients showed varying degrees of dyserythropoiesis including the presence of 2 or more nuclei, nuclei with bizarre shape and iron deposits in the mitochondria. The myeloid series showed a tendency to hypogranulation (5 patients) and in 2 patients there were signs of platelet phagocytosis. The monocytes had a normal ultrastructure except for one patient with chronic myelomonocytic leukemia (CMML) with transformation to acute myelo-monocytic leukemia (AMML). In this case, the monocytes were immature, with markedly convoluted nuclei and scanty heterochromatin. The lymphocytes also had a normal appearance, except for one patient in whom the lymphocytes were immature, with lobulated nuclei and suggested transformation of MDS to acute lymphoblastic leukemia. The plasma cells in 3 patients were slightly increased in number and in one of them Russell bodies were seen both in the cytoplasm and the nucleus. The megakaryocytic series showed a shift to the left and in one patient there were signs of emperipolesis. The alterations in the hematopoietic cells in patients with MDS described in the present study indicate that the electron microscope may supplement light microscopic findings and help in the establishment of a correct diagnosis. This may be also evident in those cases of MDS in which the very early stages of leukemic transformation cannot be easily detected by light microscopy.

Transient 7q- in association with megaloblastic anemia due to dietary folate and vitamin B12 deficiency

PURPOSE

We describe a case of acquired megaloblastic anemia in a 7 1/2 year-old white boy whose bone marrow showed unusual morphology and a nonrandom del(7q).

METHODS AND RESULTS

This patient was found to have megaloblastic anemia due to acquired folic acid and vitamin B12 deficiencies. Bone marrow examination exhibited unusual morphology, including intranuclear inclusions. Cytogenetic analysis revealed a nonrandom del(7q), a clonal abnormality usually associated with the myelodysplastic syndrome (MDS) or secondary acute myelogenous leukemia (AML). Specific treatment with both folic acid and vitamin B12 corrected the clinical as well as the marrow morphologic and cytogenetic abnormalities.

CONCLUSIONS

Megaloblastic anemia causes abnormalities in DNA synthesis and repair that may result in unusual marrow findings, both morphologic and cytogenetic. Such findings must be interpreted with caution in view of total reversibility with specific vitamin therapy.

Myelodysplastic syndromes

OBJECTIVES

To provide a framework of information from which the nurse can collaborate with the health care team to plan, coordinate, and deliver care to persons with myelodysplastic syndromes (MDS) and their families.

DATA SOURCES

Research studies, book chapters, and review articles pertaining to the classification, pathogenesis, manifestations, diagnosis, treatment, and prognosis of MDS.

CONCLUSIONS

The MDS are a group of hematologic disorders characterized by ineffective hematopoiesis, peripheral blood cytopenias, and a propensity to transform into acute myelogenous leukemia. The primary treatment is supportive care; however, chemotherapy, bone marrow transplant, and hematopoietic growth factors are also used.

IMPLICATIONS FOR NURSING PRACTICE

Assessment, education, emotional support, monitoring of complications, and provision of help to the patient with fatigue to prioritize activities and plan periods of rest are important supportive care measures.

Idiopathic macrocytic anaemia in the aged: molecular and cytogenetic findings

Macrocytosis in the elderly is often caused by abnormalities of haematological stem cell differentiation. In this study, a group of elderly patients was analysed for four molecular and cell biological parameters. The aim of the study was to screen elderly patients with idiopathic macrocytic anaemia or MDS for a set of alterations which are related to haematological dysplasia. The analyses used were: DNA-methylation at the calcitonin A gene 5'-area, NRAS point mutations at codons 12 and 13, in vitro colony formation of peripheral blood progenitor cells and cytogenetics of bone marrow cells. The results show that a significant portion of elderly patients with idiopathic macrocytosis have one or more of the abnormalities analysed. Hypermethylation of the calcitonin A gene 5'-area at the chromosome 11 band p15 is relatively common (7/15). Chromosomal aberrations (3/12) and NRAS oncogene point mutations (0/15) were rare findings. In vitro culture of erythroid progenitor cells was relatively frequently abnormal (7/15). Eight of our nine macrocytic patients who did not fulfill the FAB criteria for MDS had at least one of the alterations studied; this suggests that these patients might represent early phases of a stem cell disorder.

Heterogeneity of lineage involvement by trisomy 8 in myelodysplastic syndrome. A multiparameter analysis combining conventional cytogenetics, DNA in situ hybridization, and bone marrow culture studies

To better understand the role of trisomy 8 in myelodysplastic syndrome (MDS), we performed a multiparameter analysis combining conventional chromosome studies (CCS), fluorescence in situ hybridization (FISH), and bone marrow (BM) culture studies in two patients with MDS evolving into acute myeloid leukemia (AML). A mosaicism of a cytogenetically normal clone and a clone with trisomy 8 was detected in both patients throughout the course of the disease, a finding confirmed by FISH on BM cells. The relative size of the trisomic clone increased from 52% to 71% (p < 0.0001) and from 53% to 69% (p = 0.001) of all BM cells at the time of the leukemic switch in patients 1 and 2, respectively. Combined FISH and immunophenotyping of BM cells showed involvement of the granulomonocytic lineage in patient 1 and involvement of erythroid cells as well as of the granulomonocytic lineage in patient 2. Only disomic lymphocytes were detected in both patients. FISH on single hemopoietic colonies grown in semisolid media detected trisomic CFU-GM and disomic BFU-E in patient 1, whereas a proportion of CFU-GM and BFU-E deriving from the trisomic clone was detected in patient 2. However, the percent of trisomic colonies was lower than the percent of involved granulomonocyte precursors and involved erythroblasts, as detected by combined FISH and immunophenotyping on fresh BM samples. We have thus shown heterogeneity of lineage involvement by trisomy 8 in MDS undergoing transformation into AML. Although preferential growth of disomic clones may occur in vitro, the finding of an increased size of the trisomic clone at the time of leukemic switch suggests that these cells had proliferative advantage in vivo over cells without trisomy 8.

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.

Bone marrow pathology in relapsing polychondritis: high frequency of myelodysplastic syndromes

Haemopathologic changes were studied in 19 patients (13 male, six female, age 33-85 years, mean 56 years) with relapsing polychondritis (RP). Anaemia was found in eight, thrombocytopenia in two and splenomegaly in three patients. A total of 17 bone marrow biopsies were obtained from seven individuals. Bone marrow evaluation revealed myelodysplastic syndromes (MDS) with marked trilineage hyperplasia and dysplasia in three cases. Since an excess of myeloblasts or an increase of CD34 positive progenitor cells was not seen, the disorders were designated as 'refractory anaemia' or with regard to the dysplastic megakaryopoiesis 'MDS, unclassifiable'. Two of the three patients died after 10 and 55 months of follow-up due to infectious complications. In a further patient, bone marrow analysis repeatedly showed an unexplained granulopoietic hyperplasia, which, however, was not dysplastic enough to allow a diagnosis of MDS. The remaining patients had clearly reactive changes. Our findings support the notion that RP is a heterogenous disorder and suggest that RP may at times represent a paraneoplastic phenomenon of an underlying MDS. Since HLA typing revealed a significantly increased frequency of the antigen DR4 (10/17 patients positive = 59%), we hypothesize that immunological imbalances due to the MDS in conjunction with a specific immunogenetic background may play key roles in the pathogenesis of RP in these patients.

Use of cell surface antigen phenotype in guiding therapeutic decisions in chronic myelomonocytic leukemia

The myelodysplastic syndromes are a heterogeneous group of hematopoietic stem cell diseases in which both diagnosis and prognosis are determined by cellular morphologic criteria. In some patients, prognosis is poor due to proliferation of immature cells, i.e. development of acute leukemia. An important clinical decision for patients with myelodysplastic syndromes is whether to treat with supportive care or to use cytoreductive drugs to control the proliferative component of these illnesses. Two cases of chronic myelomonocytic leukemia are presented where cell surface antigen phenotype analysis showed characteristics suggestive of proliferative disease and the patients were treated and obtained remission with cytoablative therapy. Cell surface marker analysis may be useful in guiding therapeutic decisions in myelodysplasia.