1/40. Relapse of acute myelogenous leukemia as a cerebellar myeloblastoma showing megakaryoblastic differentiation.Myeloblastomas (granulocytic sarcomas) occurring within the central nervous system (CNS) are extremely rare lesions that may develop in patients with acute or chronic myeloproliferative disorders. The majority of such lesions involve brain or spinal cord by contiguous spread from meningeal or bony sites, rather than originating within the CNS parenchyma. We describe a patient with acute myelogenous leukemia in remission, who developed a purely intraparenchymal cerebellar myeloblastoma with megakaryocytic differentiation. The neoplastic cells expressed the megakaryocytic markers factor viii-related antigen and platelet glycoprotein-IIIa (CD61), and showed ultrastructural features that were indicative of megakaryocytic differentiation. Clinically, myeloblastomas of the CNS invoke a broad differential diagnosis that includes abscess, hemorrhage, and metastatic neoplasms because of their intraparenchymal location and radiologic features. Although they are rare, myeloblastomas should be included in the histopathologic differential diagnosis of a poorly differentiated neoplasm occurring within the CNS, particularly in a patient with a history of myeloproliferative or myelodysplastic disease.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/40. Epstein-Barr virus associated B-cell lymphoma of brain developing in myelodysplastic syndrome with c-kit mutation (Try-557 -->stop).The first case of B-cell lymphoma of brain in a patient with myelodysplastic syndrome (MDS) was reported. A 68-year-old man was admitted because of anemia, fever, and thrombocytopenia and was diagnosed as having MDS (refractory anemia with excess of blasts) on the basis of the findings of bone marrow aspiration and chromosomal analysis. The patient was followed up without chemotherapy, but a brain tumor appeared after 3 years. Histologic and immunohistologic examinations revealed diffuse large B-cell lymphoma. Mutations of the c-kit proto-oncogene (stem cell factor receptor) and the p53 tumor-suppressor gene were examined in the MDS lesion and malignant lymphoma (ML) by the polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP) method followed by direct sequencing. The p53 mutation was not found in either MDS or ML, but a nonsense mutation (Try-557 --> stop) in exon 11 of the c-kit, which might lead to dysfunction of tyrosine kinase activity, was detected in MDS. This is the first report of c-kit mutation in MDS. Epstein-Barr virus (EBV) genome was demonstrated in the nucleus of brain ML cells by in situ hybridization with EBV-encoded rna-1 probe. immunohistochemistry showed that the tumor cells expressed latent infection gene products, including EBV nuclear antigen-2 and latent membrane protein-1. This pattern of latent gene expression was Lat III, which is usually found in malignant lymphomas developing in immunocompromised hosts. These findings suggest that a profound pancytopenia in MDS resulted in an immunodeficient condition, after which EBV-positive B-cell lymphoma of brain developed.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/40. Non-caseating granulomata associated with hypocellular myelodysplastic syndrome.Non-caseating granuloma (NCG) remains a histopathological hallmark for sarcoidosis. Although the exact mechanism for NCG formation is unknown, the pathogenesis may involve a disordered antigen presentation in the monocyte/macrophage system, functional abnormalities in activated t-lymphocytes and uncontrolled cytokine production. Similar immunological dysfunction has been described in myelodysplastic syndrome (MDS). However, the association of NCG and MDS is rarely documented. We report a case of hypocellular MDS associated with generalized NCG. Despite treatment for both sarcoidosis and tuberculosis, the patient failed to respond. A clonal myeloid disorder which was initially suppressed by T-cell immunosurveillance evolved after treatment with anti-thymocyte globulin. Although the coexistence of sarcoidosis remains a possibility, the lack of supportive clinical evidence of sarcoidosis, the abnormal appearances of the bone marrow, together with the failure to improve on high-dose steroid favour the clonal myeloid disorder as the sole pathology.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
4/40. Allogeneic bone marrow transplantation-mediated transfer of specific immunity against toxocara canis associated with excessive IgE.A girl with myelodysplastic syndrome (RAEB-T) received HLA-identical bone marrow from her younger brother after myeloablative treatment with busulfan and cyclophosphamide. After bone marrow transplantation, fever, exanthema, pruritis, and a pulmonary infiltrate were treated symptomatically. Bacterial cultures remained negative. Leukocyte engraftment began on day 10, and all blood cell populations proved to be of donor origin on FISH analysis. Increasing IgE levels (21 000 U/ml) on day 14 after BMT, positive RAST, specific IgG-antibodies, and missing Toxocara (T.) canis antigens in the recipient indicated donor-derived seroconversion. Before BMT, the recipient had been negative for T. canis in routine parasitological screening, and the donor proved to be positive for T. canis antibody by ELISA. This report suggests that the transfer of IgE immunity in the absence of detectable antigens may be responsible for IgE-mediated symptoms consistent with toxocara infection and confirms the need for parasite screening in donor medical examinations.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
5/40. Burkitt's acute lymphoblastic leukaemia transformation after myelodysplastic syndrome.We describe a patient with myelodysplastic syndrome (MDS) that transformed to Burkitt's acute lymphoblastic leukaemia (ALL). The leukaemic blasts were negative for peroxidase staining, and expressed CD10, CD19, CD22, CD38, human leucocyte antigen (HLA)-DR and surface immunoglobulin (sIg) M, but neither sIgD nor sIgG were expressed. Chromosomal study during the ALL phase showed t(8;22)(q24;q11) in addition to the karyotypes determined during the MDS phase. Furthermore, overexpression of c-myc mRNA was confirmed in ALL blasts. These findings indicate that MDS transformed to Burkitt's ALL through multiple cytogenetic evolutions, the final event of which seems to be overexpression of the c-myc gene.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/40. risk factors for cytomegalovirus retinitis following bone marrow transplantation from unrelated donors in patients with severe aplastic anemia or myelodysplasia.Two cases of cytomegalovirus (CMV) retinitis following bone marrow transplantation (BMT) from unrelated donors are reported. 1 patient had been treated for severe aplastic anemia (SAA) and the other for hypoplastic myelodysplastic syndrome (MDS). Because first line therapy with antithymocyte globulin (ATG) and cyclosporin A (CsA) had failed, BMT was performed following a conditioning regimen of ATG, cyclophosphamide, and total lymphoid irradiation. Treatment for CMV retinitis was successfully carried out with gancyclovir (systemic and intraocular injection), foscarnet, and photocoagulation (Case 1) and gancyclovir and foscarnet (Case 2). Both patients also developed Epstein-Barr virus-associated lymphoproliferative disease (EBV-LPD). We compared these 2 cases with 14 SAA patients who did not develop CMV retinitis after BMT using marrow from either HLA-identical siblings (n = 9) or from unrelated donors (n = 5). Unlike the retinitis patients, the latter 5 patients received ATG only once. The retinitis patients had significantly lower CD4 T-cell levels in their peripheral blood than the 14 patients who did not develop CMV retinitis. We believe that repeated treatment with ATG and transplantation from unrelated donors may lead to immune dysfunction that could increase the likelihood of CMV retinitis, as well as LPD. For such BMT patients, regular ophthalmic examinations and careful testing for CMV antigenemia are recommended.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
7/40. Expression of CD4 on peripheral blood granulocytes. a novel finding in a case of myelodysplastic syndrome in association with t(5;12).myelodysplastic syndromes (MDS) are associated with cell maturation defects that can manifest as abnormal surface antigen expression. We describe a patient with refractory anemia with excess blasts, who presented with infection and extensive dysplastic features in peripheral blood granulocytes. The granulocytes expressed CD11b, CD13, CD15, CD33, and CD43. The granulocytes also expressed CD4 antigen. cytogenetic analysis showed a clonal t(5;12)(q33;p13). The patient improved on antibiotics with partial improvement in the dysplastic features. However, shortly after, the patient experienced paravertebral extramedullary blast transformation followed by a leukemia phase of acute monoblastic leukemia. The patient died a few days later. This is the first report describing anomalous expression of CD4 on granulocytes in MDS. Since the breakpoint on chromosome 12 is near the CD4 gene, which is mapped to 12p12, we hypothesize that dysregulation of the CD4 gene may have occurred resulting in its persistent expression on mature and maturing granulocytes.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
8/40. Donor-cell myelodysplastic syndrome developing 13 years after marrow grafting for aplastic anemia.Donor-cell-derived hematopoietic malignancy is a rare event after bone marrow transplantation. Most cases in the literature occurred within the first year. We present a rare case of a female patient who had a bone marrow transplant for severe aplastic anemia (SAA) at the age of two and a half years from her human leukocyte antigen-identical brother. She developed a myelodysplastic syndrome (refractory cytopenia with multilineage dysplasia) 12 years later. Initially, the malignant clone was of recipient origin, but within several months, progression to a clinically more aggressive refractory anemia with excess blasts (RAEB) was accompanied by the outgrowth of a new clone of donor origin. In this report we provide evidence proving that the patient's final malignant clone arose in donor cells: cytogenetic analysis of the marrow showed a male karyotype and a t(3;21)(q26;q21) in all 62 metaphases analyzed. interphase fluorescence in situ hybridization showed that all identifiable cells contained the y chromosome. We conclude that donor-cell-derived hematopoietic malignancy after bone marrow transplantation can occur even after many years. We believe that the 13 years that elapsed between the transplant and the development of RAEB in our case represent the longest latency period in the literature.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
9/40. Retinal S-antigen-reactive lymphocytes in a patient with uveitis associated with myelodysplastic syndromes.BACKGROUND: Although autoimmune humoral abnormalities have been reported in patients with myelodysplastic syndromes (MDS), abnormal organ-specific cellular autoimmunity has not been demonstrated. methods: Peripheral blood lymphocytes (PBLs) and serum were collected from a uveitis patient with MDS. Cellular immune response against retinal S-antigen (S-Ag) was assessed by proliferation assay, and humoral immune response to S-Ag was measured by enzyme-linked immunosorbant assay. RESULTS: PBLs from the patient exhibited vigorous proliferation against S-Ag, while humoral immune response against S-Ag was not detectable. PBLs from controls did not proliferate against S-Ag. CONCLUSION: These results provide new evidence that abnormal cellular immune responses against autoantigens may develop in MDS patients, thus leading to organ-specific autoimmune diseases such as uveitis, in addition to other systemic autoimmune disorders.- - - - - - - - - - ranking = 6keywords = antigen (Clic here for more details about this article) |
10/40. wilms tumor gene peptide-based immunotherapy for patients with overt leukemia from myelodysplastic syndrome (MDS) or MDS with myelofibrosis.The wilms tumor gene, WT1, is overexpressed not only in leukemias and myelodysplastic syndrome (MDS) but also in various types of solid tumors, including lung and breast cancer, and the WT1 protein is a tumor antigen for these malignancies. In clinical trials of WT1 peptide-based cancer immunotherapy, patients with overt leukemia from MDS or MDS with myelofibrosis were injected intradermally with 0.3 mg of an HLA-A*2402-restricted, 9-mer WT1 peptide emulsified with Montanide ISA51 adjuvant. Only a single dose of WT1 vaccination resulted in an increase in WT1-specific cytotoxic t-lymphocytes, which was followed by a rapid reduction in leukemic blast cells. Severe leukopenia and local erythema at the injection sites of WT1 peptide were observed as adverse effects. These results have provided us with the first clinical evidence suggesting that WT1 peptide-based immunotherapy is an attractive treatment for patients with leukemias or MDS.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
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