Cases reported "Leukemia, Mast-Cell"

Filter by keywords:



Retrieving documents. Please wait...

1/19. Immunohistochemical properties of bone marrow mast cells in systemic mastocytosis: evidence for expression of CD2, CD117/Kit, and bcl-x(L).

    In an attempt to identify novel diagnostic markers for mast cell (MC)-proliferative disorders, serial bone marrow (bm) sections of 22 patients with mastocytosis (systemic indolent mastocytosis, n = 19; mast cell leukemia [MCL], n = 1; isolated bm mastocytosis, n = 2) were analyzed by immunohistochemistry using antibodies against CD2, CD15, CD29, CD30, CD31, CD34, CD45, CD51, CD56, CD68R, CD117, HLA-DR, bcl-2, bcl-x(L), myeloperoxidase (MPO), and tryptase. Staining results revealed expression of bcl-x(L), CD68R, and tryptase in neoplastic MCs (focal dense infiltrates) in all patients. mastocytosis infiltrates were also immunoreactive for CD45, CD117 (Kit), and HLA-DR. In most cases, the CD2 antibody produced reactivity with bm MCs in mastocytosis, whereas in control cases (reactive bm, immunocytoma, myelodysplastic syndrome), MCs were consistently CD2 negative. Expression of bcl-2 was detectable in a subset of MCs in the patient with MCL, whereas no reactivity was seen in patients with SIM or bm mastocytosis. mastocytosis infiltrates did not react with antibodies against CD15, CD30, CD31, CD34, or MPO. In summary, our data confirm the diagnostic value of staining for tryptase, Kit, and CD68R in mastocytosis. Apart from these, CD2 may be a novel useful marker because MCs in mastocytosis frequently express this antigen, whereas MCs in other pathologic conditions are CD2 negative. ( info)

2/19. low back pain and myalgias in acute and relapsed mast cell leukemia: a case report.

    Mast cell leukemia is a rare, severe disease that may manifest through an array of clinical presentations, including vasomotor flushing and hypotension. Leukemic infiltrate of muscle and bone may rarely occur, resulting in nonspecific myalgias, bony pain, and neuropathic pain secondary to compression of nerves by bone. Mast cell leukemia as a clinical entity has not been well described. We present the case of a 25-year-old man with a remote medical history of germ cell tumor who was initially diagnosed with mast cell leukemia after presenting with low back pain. One and a half years later, the patient presented with a chief complaint of back pain and myalgias and was found to have relapsed mast cell leukemia. Medical management and, specifically, rehabilitation of these patients can be extremely difficult. This report shows the complex management of patients with mast cell leukemia. ( info)

3/19. Rapid engraftment of mast cells of donor origin in a case of acute myeloid leukemia with mast cell leukemia after allogeneic stem cell transplantation.

    mastocytosis is a rare disease characterized by an abnormal increase of mast cells in tissues. We report a case of acute myeloid leukemia (AML) with t(8;21) and mast cell leukemia (MCL) in which the mastocytosis persisted after standard chemotherapy and allogeneic stem cell transplantation, although the myeloid leukemia achieved molecular complete remission soon after induction chemotherapy. Donor-type mast cells were noted on d31 after transplant. No c-kit mutation was found before or after the transplant. This represents the first reported case in which rapid engraftment of mast cells of donor origin was documented. Thus, the possibility that the mast cell originates from a common myeloid precursor cell may be questioned and a reactive process should be considered in some cases of systemic mastocytosis. ( info)

4/19. Response to therapy with interferon alpha-2b and prednisolone in aggressive systemic mastocytosis: report of five cases and review of the literature.

    Aggressive systemic mastocytosis (ASM) is a hematopoietic neoplasm characterized by infiltration of visceral organs by neoplastic mast cells (MCs) with consecutive organopathy and respective clinical and laboratory findings (so called C-Findings). Whereas, it is generally appreciated that patients with ASM are candidates for pharmacological intervention, no ideal drug or drug combination have been identified yet. One drug proposed to work in ASM is interferon alpha-2b (IFN-alpha2b). However, little is known so far about the quality of responses to IFN-alpha2b and actual response rates. We here report on five ASM patients treated with either a combination of IFN-alpha2b (3x3 million units per week) and prednisolone (n=4), or IFN-alpha2b alone (n=1). During therapy, two of the five patients showed a major response defined by complete resolution of C-Finding(s), one a partial response (partial regression of C-Findings), and one a stable disease (no changes in C-Findings). In one patient, progression to mast cell leukemia was seen after 3 months. In contrast to the other patients, this patient exhibited >10% MCs in his bone marrow (bm) smear at first presentation. In summary, our data confirm beneficial effects of IFN-alpha2b (plus prednisolone) for a group of patients with ASM, whereas patients with mast cell leukemia may require more aggressive therapy. Prospective trials with more patients are now required to further document these drug effects and to better define subgroups of patients with ASM who show good and long-lasting responses to IFN-alpha2b. ( info)

5/19. Evidence for a graft-versus-mast-cell effect after allogeneic bone marrow transplantation.

    Mast cell leukemia (MCL) is a rare form of aggressive mastocytosis with a reported median survival below 6 months. Casuistic reports suggest the effectiveness of allogeneic bone marrow transplantation (BMT) for MCL. However, these reports lack clear evidence for a graft-versus-mast-cell (GvMC) effect. We prospectively investigated the GvMC at different time points after allogeneic BMT and donor-lymphocyte infusions (DLI). Samples were gathered from a patient with MCL treated with allogeneic BMT from an unrelated HLA identical donor. Parameters for detection of a GvMC effect included flow cytometrical analysis of mast cell (MC) populations in peripheral blood and BM, BM smear and histology, chimerism analysis of flow cytometrically sorted BM CD117 /CD34- MC and testing for anti-mast cell reactivity of donor lymphocytes by interferon (IFN)-gamma ELISPOT. DLIs reduced MC from 5 to 0.5%. MC chimerism analysis demonstrated a complete recipient genotype after BMT, suggesting that the persistent mastocytosis was part of residual neoplastic disease. At 3.7 years after BMT, there is some evidence for relapse. In summary, BMT and DLIs attenuated the mastocytosis from an aggressive to an indolent form and may have improved the patients' prognosis. The in vitro data of our study indicate for the first time the existence of a GvMC effect. ( info)

6/19. Aleukemic mast cell leukemia with abnormal immunophenotype and c-kit mutation D816V.

    mastocytosis comprises a heterogeneous group of disorders characterized by proliferation and accumulation of mast cells in 1 or more organ systems. Mast cell leukemia (MCL) is an extremely rare subtype of mastocytosis in which a leukemic spread of mast cells and a rapid progression of disease is seen. In typical cases, mast cells are found in the peripheral blood. However, an aleukemic variant of MCL (formerly termed malignant mastocytosis) has also been described. We here report a case of aleukemic MCL with abnormal immunophenotype of mast cells and the classical c-kit point mutation Asp-816-Val (=D816V). The 75-year-old male patient had a short history of weight loss and lymphadenopathy. There were no urticaria pigmentosa-like skin lesions. The bone marrow was diffusely infiltrated with atypical mast cells that comprised more than 80% of all nucleated cells on a bone marrow smears. As assessed by immunohistochemistry, neoplastic mast cells expressed tryptase, chymase, CD2, CD25, CD68, and the KIT protein (CD117). Mutation analysis revealed the c-kit mutation D816V. Since circulating mast cells could not be detected in the peripheral blood, the diagnosis of aleukemic MCL was established in accordance to the updated WHO consensus classification. This case further supports the notion that the pathogenesis (c-kit mutation D816V) in MCL is closely related to that found in indolent mast cell disorders. However, additional (but yet unknown) molecular (genetic) defects have to be considered to explain the extremely heterogenous clinical course in these patients. ( info)

7/19. Activity of the tyrosine kinase inhibitor PKC412 in a patient with mast cell leukemia with the D816V KIT mutation.

    The majority of patients with systemic mast cell disease express the imatinib-resistant Asp816Val (D816V) mutation in the KIT receptor tyrosine kinase. Limited treatment options exist for aggressive systemic mastocytosis (ASM) and mast cell leukemia (MCL). We evaluated whether PKC412, a small-molecule inhibitor of KIT with a different chemical structure from imatinib, may have therapeutic use in advanced SM with the D816V KIT mutation. We treated a patient with MCL (with an associated myelodysplastic syndrome (MDS)/myeloproliferative disorder [MPD]) based on in vitro studies demonstrating that PKC412 could inhibit D816V KIT-transformed Ba/F3 cell growth with a 50% inhibitory concentration (IC50) of 30 nM to 40 nM. The patient exhibited a partial response with significant resolution of liver function abnormalities. In addition, PKC412 treatment resulted in a significant decline in the percentage of peripheral blood mast cells and serum histamine level and was associated with a decrease in KIT phosphorylation and D816V KIT mutation frequency. The patient died after 3 months of therapy due to progression of her MDS/MPD to acute myeloid leukemia (AML). This case indicates that KIT tyrosine kinase inhibition is a feasible approach in SM, but single-agent clinical efficacy may be limited by clonal evolution in the advanced leukemic phase of this disease. ( info)

8/19. philadelphia chromosome-negative acute hematopoietic malignancy: ultrastructural, cytochemical and immunocytochemical evidence of mast cell and basophil differentiation.

    We describe a patient with fever and multiple osteolytic bone lesions accompanied by hypercalcemia, a duodenal ulcer, anemia, and thrombocytopenia. Bone marrow showed a dense infiltration by abnormal cells characterized by small basophil granula, erythrophagocytosis and nuclear atypia. These cells were positive for toluidine blue and partly for myeloperoxidase and chloroacetate esterase, expressed myeloid differentiation markers, and exhibited multiple numerical and structural chromosome aberrations. Molecular genetic analysis showed no breakpoint cluster region rearrangement. Electron microscopy demonstrated granula both of basophil and mast cell type. Concluding, in this patient an acute hematopoietic malignancy with many features of malignant mastocytosis but also with signs of a basophil differentiation. This is further support for a hematopoietic stem cell origin of human mast cells. ( info)

9/19. Malignant mastocytosis with circulating mast cells.

    A case of malignant mastocytosis with peripheral blood involvement is presented. The course of the patient's illness was complicated by recurrent hypotensive episodes, presumed to have been caused by mast cell degranulation. Treatment with hydroxyurea was associated with persistent hypotension which resulted in death. It has been proposed that the diagnosis of mast cell leukemia be given to patients presenting with greater than 10% atypical mast cells in the blood. However, review of 16 published cases of malignant mastocytosis with circulating mast cells reveals that the clinical manifestations, complications, and survival do not vary significantly with the percentage of peripheral blood mast cells. patients with malignant mastocytosis with significant involvement by atypical mast cells in the bone marrow and peripheral blood should be considered as having an aggressive disease, regardless of the percentage of circulating mast cells. ( info)

10/19. A case of malignant mastocytosis with near-haploid, near-diploid, and polyploid cells in the bone marrow.

    Chromosome analysis in bone marrow cells of a 41-year-old woman with malignant mastocytosis (MM) revealed near-haploid (59%), near-diploid (36%), and polyploid (5%) cells. Near-haploid cells had a mode of 25 chromosomes with variable disomy and nullisomy of particular chromosomes. Disomy for chromosome 19 and chromosome 20 were most common. A 17p marker was observed in all cells. Other structural chromosomal changes were dicentrics, ring chromosomes, translocations, and double minutes. The modal chromosome number in near-diploid cells was 46 with a range of 41-52. The majority of cells with 46 chromosomes were pseudodiploid and only a few had a normal female karyotype. As in near-haploid cells, various structural chromosomal changes were found. The 17p marker was also present in occasional cells suggesting a relationship between the two tumor cell populations. Chromosome numbers in polyploid cells ranged from 70 to about 600. Identical copies of dicentrics or markers were identified in some cells. ( info)
| Next ->


Leave a message about 'Leukemia, Mast-Cell'


We do not evaluate or guarantee the accuracy of any content in this site. Click here for the full disclaimer.