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W Heit

Publications and source records attributed to W Heit.

At least 19 recordsLinked to original sources
PubMed2006

HLA-identical sibling allogeneic peripheral blood stem cell transplantation with reduced intensity conditioning compared to autologous peripheral blood stem cell transplantation for elderly patients with de novo acute myeloid leukemia.

We conducted a retrospective registry-based analysis to compare the outcome of 361 allogeneic human leukocyte antigen (HLA)-identical peripheral blood stem cell transplants (PBSCT) with reduced intensity conditioning (RIC) to that of 1369 autologous (auto) PBSCT in patients aged 50 years or older with de novo acute myeloid leukemia (AML), performed from 1997 until 2003 and reported to the European Group for Blood and Marrow Transplantation. Median age was 58 and 57 years in the RIC and auto groups, respectively. RIC patients had more advanced disease at the time of transplant. At a median follow-up of 24 months for RIC and 16 months for auto, multivariate analysis showed a lower risk for relapse (RR 0.77, P=0.013) without increased non-relapse mortality (NRM) in RIC patients (RR 1.26, P=0.28). Moreover, leukemia-free survival (RR 1.22, P=0.02) and overall survival (OS) (RR 1.32, P=0.005) were superior in the RIC group. In patients in 1st (CR), fewer relapses were counterbalanced by significantly increased NRM. Therefore, there was no survival advantage in this subgroup. In patients in 2nd or subsequent CR, LFS and OS were superior in the RIC group. RIC transplants show encouraging results in this older patient population with de novo AML.

Aged↗
PubMed1997

Indications for and results of splenectomy in different hematological disorders.

The objective of this retrospective study was to determine the indications for splenectomy in hematological disorders and to analyze the results depending on the indication leading to surgery. Fifty-six patients with various hematological disorders were splenectomized between 1990 and 1994. The main indication was noted. Operative success was defined as: return to normal platelet counts without further medication in thrombocytopenia, relief of pain and local compression syndrome in painful splenomegaly, hemoglobin levels > 10 g/dl without the need for further transfusions in hemolytic anemia, response to chemotherapy after splenectomy for prior resistance because of massive splenic infiltration, and relief of infection in splenic infection. Morbidity and mortality were noted. Five major indications for splenectomy were found: thrombocytopenia (n = 36, success 78%), painful splenomegaly (n = 8, success 100%), hemolytic anemia (n = 5, success 60%), resistance to chemotherapy because of massive splenic infiltration (n = 5, success 100%). One patient with thrombocytopenia died (mortality 2%). Seven patients had major complications (13%). In hematological diseases, thrombocytopenia, painful splenomegaly and splenic infection are likely to be improved by splenectomy. In hemolytic anemia it can be a helpful approach, while in resistance to chemotherapy because of massive splenic infiltration success is less likely.

Female↗
PubMed1996

[Splenectomy in osteomyelofibrosis. Indications and outcome].

Osteomyelofibrosis is a myeloproliferative disorder in which fibrosis and sclerosis finally lead to bone marrow obliteration. Liver and spleen compensate for bone marrow loss with extramedullary hematopoiesis. In some patients the resulting splenomegaly causes severe symptoms such as local compression, thrombocytopenia and hemolytic anemia. In such patients, splenectomy is the only promising treatment, although it represents a significant risk.

Adult↗
PubMed1996

Simultaneous presence of t(11;14) and a variant Burkitt's translocation in the terminal phase of a mantle cell lymphoma.

Little is known about the clinical significance of secondary chromosome aberrations in lymphomas with t(11;14)(q13;q32), the characteristic change of mantle cell lymphomas. Here we present a patient with mantle cell lymphoma, who showed a variant Burkitt's translocation t(2;8)(p12;q24) in addition to t(11;14) during the progression of the disease. An involvement of chromosome 8q24, the localization of the c-myc gene, has so far been described in only four patients, who seemed to have a fatal clinical course. Although no blastic transformation occurred in our patient, no remission could be induce by intensified treatment and survival was only 5 months. This case demonstrates that secondary chromosome aberrations can determine the clinical course of patients, even if morphologic and immunophenotypic findings fail to predict the poor outcome.

Blotting, Southern↗
PubMed1995

In vivo/ex vivo T cell depletion reduces the morbidity of allogeneic bone marrow transplantation in patients with acute leukaemias in first remission without increasing the risk of treatment failure: comparison with cyclosporin/methotrexate.

We have performed a non-randomised GVHD prophylaxis trial comparing cyclosporin/methotrexate with in vivo/ex vivo T cell depletion with the monoclonal antibodies Campath 1G/1M in patients with acute leukaemias in first complete remission. We observed significantly less acute and chronic GVHD, neutropenic fever and severe mucositis in the T cell depletion group. The incidence of graft rejection and relapses was no higher than in the cyclosporin/methotrexate group. There is a trend in favour of improved disease-free survival in the in vivo/ex vivo T cell depletion group (80% vs. 62%).

Acute Disease↗
PubMed1994

Structural analysis of the deoxycytidine kinase gene in patients with acute myeloid leukemia and resistance to cytosine arabinoside.

Deficiency of deoxycytidine kinase (dCK) activity represents one possible cause of resistance to cytosine arabinoside (ara-C). Mutations of the dCK gene have recently been shown to be responsible for dCK deficiency and increased resistance in vitro. In order to define the relevance of this mechanism in vivo, we analyzed the dCK gene in 16 adult patients with relapsed/refractory acute myeloid leukemia (AML) and clinical resistance to standard-dose and/or high-dose ara-C. Southern blot analysis using genomic DNA from peripheral blood or bone marrow samples containing > or = 70% leukemic blasts and agarose gel electrophoresis of cDNA obtained by RT-PCR did not reveal gross rearrangements of the dCK gene. Sequencing of the dCK coding region showed point mutations in seven patients. Besides two silent mutations (or RFLPs) in codon 42 and 86, base pair mutations resulting in amino acid replacements were found in five patients affecting codon 20, 93, 98, 99, and 154, respectively. dCK cDNA clones from three patients with > or = 50% of sequenced clones revealing the specific base pair alteration were bacterially expressed in E. coli and analyzed for dCK activity. Normal enzyme activity was found in two patients (codon 20 and 98), and a complete loss of activity in one patient (codon 99). We conclude that structural alteration of the coding region of the dCK gene represents one possible mechanism for ara-C resistance in vivo, but, considering the frequency of this event, other mechanisms may play a more important role for clinical resistance to ara-C in patients with AML.

Adult↗
PubMed1993

Simultaneous administration of granulocyte colony-stimulating factor (Filgrastim) and induction chemotherapy in acute lymphoblastic leukemia. A pilot study.

The present study was designed to determine whether Filgrastim, a neutrophil-specific hematopoietic growth factor, could be administered simultaneously with intensive induction chemotherapy for adult acute lymphoblastic leukemia (ALL). The effect of Filgrastim on the severity of chemotherapy-induced neutropenia, fever, and infections was assessed in 15 patients treated according to the protocol of the German multicenter ALL (GMALL) trial 04/89. Filgrastim (5 micrograms/kg/day) was given concurrently with successive cycles of cyclophosphamide, cytosine-arabinoside (ara-C), 6-mercaptopurine (6MP), prednisone (PRD), intrathecal methotrexate, and prophylactic cranial irradiation. During the study period the median total duration of severe neutropenia (< 0.5 x 10(9)/l) in 13 evaluable patients was 8 days, individual periods of neutropenia typically were short. Infections occurred in six patients; seven patients remained fever-free during treatment with Filgrastim. We conclude that simultaneous treatment with Filgrastim and chemotherapy in this specific setting is feasible and well tolerated. The efficacy of this treatment approach in terms of overall treatment results requires further testing in a randomized trial.

Adolescent↗
PubMed1993

Aggressive chemotherapy combined with G-CSF and maintenance therapy with interleukin-2 for patients with advanced myelodysplastic syndrome, subacute or secondary acute myeloid leukemia--initial results.

Aggressive chemotherapy of advanced myelodysplastic syndrome (MDS), acute myeloid leukemia (AML) evolving from MDS, subacute AML and secondary AML has usually been associated with low complete remission (CR) rates, a high incidence of early death, and low disease-free survival. We therefore have initiated a phase-III trial of aggressive chemotherapy consisting of idarubicin, cytosine arabinoside, and VP-16 to improve the CR rate. Each chemotherapy cycle is followed by G-CSF to accelerate neutrophil recovery and to reduce the incidence of infections. Until now, 19 patients with high-risk AML have been entered. The CR rate is 47%, with only one death during induction. Patients achieving CR are randomized to receive either high-dose or low-dose interleukin-2 to eliminate residual leukemic cells and to prolong the duration of remission.

Adult↗
PubMed1993

Frequency of bone marrow T cells responding to HLA-identical non-leukemic and leukemic stimulator cells.

Grafted immunocompetent cells are considered responsible for GVHD as well as for the elimination of residual leukemic cells ('graft-versus-leukemia reactivity', GVLR) in leukemic patients after allogeneic BMT. Clinical and experimental investigations have given contradictory answers to the question whether GVHD and GVLR are two manifestations of the same process or separate immunologic processes. We have addressed this question by analysing the primary in vitro response of BM-derived proliferating and cytotoxic T lymphocyte precursors (PTLp and CTLp) in HLA identical relative pairs (n = 17). PTLp frequency estimation reveals strong responses (> 1 in 5000) on non-leukemic as well as leukemic stimulation in a majority of cases. CTLp amount variably to 10-100% of the proliferating precursor cells. Preliminary specificity analyses show that on non-leukemic stimulation about 90% of colonies exhibit exclusive lysis of the non-leukemic target. At the same time, on leukemic stimulation, about 75% of cytolytic colonies are exclusively reactive against leukemic targets without crossreactivity against nonleukemic targets from the same patient. Our data show that primary in vitro responses in HLA identical sibling pairs may be as strong as those against allo MHC antigens. In addition CTL specifically lysing leukemic or non-leukemic targets may represent an in vitro model of the immunologic non-identity of GVHD and GVLR.

Bone Marrow↗
PubMed1992

AMSA combination chemotherapy in patients with acute myelogenous leukemia unsuitable for standard antileukemic treatment.

Forty-eight patients with acute myelogenous leukemia (AML) not eligible for anthracycline or mitoxantrone treatment, mostly due to cardiac contraindications, were given aggressive therapy using m-amsacrine (AMSA) in combination with conventional or high-dose cytarabine for remission induction. Twenty-nine patients (60.4%) responded to treatment, and complete remission was attained in 19 (39.6%), partial remission in 4 (8.3%) and death in bone marrow aplasia without detectable blasts in 6 patients (12.5%). Median time to granulocyte recovery was 32 days, median duration of relapse-free survival 199 days. One patient experienced a serious cardiac adverse event; nausea and vomiting were observed in 73%, diarrhea in 44%, and hepatoxicity in 29% of patients. All potentially AMSA-related side effects were fully reversible, and a lethal complication did not occur. It is concluded that combination chemotherapy with AMSA and Ara-C is also effective and tolerable in leukemic patients in whom cardiotoxic drugs are contraindicated.

Adult↗
PubMed1992

ABO-incompatible bone marrow transplantation.

In the past 10 years 201 HLA-identical bone marrow transplantations (BMT) were performed with major ABO incompatibility in 41 (20%) and minor ABO incompatibility in 35 (18%) patients. ABO compatibility between donor and recipient showed no influence on granulocyte and platelet recovery after BMT. Erythrocyte reconstitution was significantly (p < 0.01) delayed for about 1 week in major ABO-incompatible BMT. In addition, a pure red cell aplasia lasting for 2-5 months occurred in 6 out of 21 blood group 0 patients who received transplants of group A. The rate of graft rejection, incidence of graft-versus-host disease as well as the leukemic relapse rate were similar in ABO-compatible and ABO-incompatible BMT. The probability of a 10-year survival after BMT is independent of ABO compatibility between donor and recipient.

ABO Blood-Group System↗
PubMed1990

Transient pancytopenia. A report from the International Agranulocytosis and Aplastic Study.

From a population-based study on the incidence of potentially drug-associated blood dyscrasias 28 cases were identified with pancytopenia. Who recovered within 90 days after diagnosis. Early recovery occurred more frequently in patients showing normal or increased cellularity of the bone marrow than in patients with bone marrow hypoplasia. Median recovery times of leukocytes were 14 and 10 days and of platelets 21 and 9 days in patients with and without bone marrow hypoplasia, respectively. Age and sex distribution were similar in both groups. Of 28 patients, 11 reported a period of fever before onset of pancytopenia. Sixteen patients in whom information on drug use was available had taken a median of 4 drugs before the onset of symptoms that were related to pancytopenia. From these results we present the hypothesis that transient pancytopenia with or without marrow hypoplasia can be the expression of the same type of bone marrow injury and that drugs or viral infections should be considered as etiological factors.

Agranulocytosis↗
PubMed1990

Comparative analysis of in vivo T cell depletion with radiotherapy, combination chemotherapy, and the monoclonal antibody Campath-1G, using limiting dilution methodology.

We have investigated the efficacy of standard conditioning regimens for bone marrow transplantation in depleting functional T lymphocytes in vivo and have compared it with the efficacy of the monoclonal antibody Campath-1G. Using limiting dilution techniques the frequencies of proliferating T cell precursors (PTL), cytotoxic T cell precursors (CTL-p), helper T cell precursors (HTL-p), and mature helper T cells (HTL) were determined before and after treatment. Both total body irradiation and combination chemotherapy with busulfan/cyclophosphamide were highly efficient at depleting PTL, CTL-p, and HTL-p (0-4 days) but spared HTL to a variable extent (0-99.5%). In the majority of patients treated with Campath-1G a similar degree of PTL, CTL-p, and HTL-p depletion was achieved, and, in addition, HTL were effectively removed (greater than 95.5%). These results suggest that Campath-1G could be successfully employed in depleting radio- and chemotherapy-resistant host T lymphocytes prior to T-depleted bone marrow transplantation.

Antibodies, Monoclonal↗
PubMed1990

Frequency, specificity, and phenotype of clonally growing human alloreactive interleukin-2-secreting helper T lymphocyte precursors.

Limiting dilution cultures were performed to detect allospecific IL-2-secreting helper T lymphocyte precursors (HTL-p) among human peripheral blood mononuclear cells, E-rosette-purified (E+) and cell-sorter-separated CD4+/8- as well as CD4-/8+ T cell subsets. Split-well cultures were set up prior to restimulation to assess the antigen specificity of the response. Frequencies of alloreactive IL-2-secreting HTL-p in fully HLA-mismatched responder/stimulator cell combinations ranged from 1/200 to 1/900 (among PBMNC), from 1/50 to 1/301 (among E+ T cells), from 1/36 to 1/220 (among CD4+ T cells), and from 1/38 to 1/450 (among CD8+ T cells). Allospecificity of effector T cells was demonstrated by a strong decline of frequencies obtained after restimulation against unrelated third-party antigens. In clonal segregation analysis, the vast majority of IL-2-secreting progeny (80-90%) were exclusively specific for the original stimulating alloantigen. Finally, the allele specificity of human alloreactive HTL-p was revealed by comparing frequency estimates obtained after restimulation with partially identical stimulator/third-party antigen combinations.

Alleles↗
PubMed1990

Graft failure after T cell-depleted bone marrow transplantation: clinical and immunological characteristics and response to immunosuppressive therapy.

We have investigated the clinical and immunological features of 10 cases of graft failure after T cell-depleted marrow transplantation. In addition, the hypothesis that the process of graft failure can be reversed by immunosuppressive therapy with cyclosporin + steroids +/- monoclonal antibodies was tested in seven patients. Early graft failures (before day 50) presented a uniform clinical syndrome with a host T lymphocytosis preceding the loss of the graft. In the majority of cases of late graft failure (after day 50) a syndrome comprising delayed granulopoietic regeneration, fever of unknown origin and abdominal symptoms was observed. Surface marker analysis of peripheral blood and bone marrow lymphocytes implicated a population of CD3+, CD8+, DR+ host T lymphocytes with a frequent co-expression of the Leu7+ antigen in the pathogenesis of graft failure. Immunosuppressive therapy reversed graft failure in the three cases of incomplete graft failure (i.e. with residual reticulocytes) and failed in the four cases of complete graft failure (i.e. no residual reticulocytes).

Antibodies, Monoclonal↗