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Biomedical subjects

H Döhner

Publications and source records attributed to H Döhner.

At least 37 records · Page 2Linked to original sources

Consolidation with alemtuzumab in patients with chronic lymphocytic leukemia (CLL) in first remission--experience on safety and efficacy within a randomized multicenter phase III trial of the German CLL Study Group (GCLLSG).

Patients with CLL responding to initial chemotherapy with fludarabine alone (F) or in combination with cyclophosphamide (FC) were randomized for treatment with alemtuzumab (30 mg i.v. TIW, 12 weeks) or observation. Of 21 evaluable patients, 11 were randomized to alemtuzumab before the study was stopped due to severe infections in seven of 11 patients. These infections (one life-threatening pulmonary aspergillosis IV; four CMV reactivations III requiring i.v. ganciclovir; one pulmonary tuberculosis III; one herpes zoster III) were successfully treated and not associated with cumulative dose of alemtuzumab. In the observation arm, one herpes zoster infection II and one sinusitis I were documented. At 6 months after randomization, two patients in the alemtuzumab arm converted to CR, while three patients in the observation arm progressed. After alemtuzumab treatment, five of six patients achieved a molecular remission in peripheral blood while all patients in the observation arm remained MRD-positive (P=0.048). At 21.4 months median follow-up, patients receiving alemtuzumab showed a significant longer progression-free survival (no progression vs mean 24.7 months; P=0.036). In conclusion, a consolidation therapy with alemtuzumab is able to achieve molecular remissions and longer survival in CLL, but a safe treatment regimen needs to be determined.

Adult↗

Comparative analysis of minimal residual disease detection using four-color flow cytometry, consensus IgH-PCR, and quantitative IgH PCR in CLL after allogeneic and autologous stem cell transplantation.

The clinically most suitable method for minimal residual disease (MRD) detection in chronic lymphocytic leukemia is still controversial. We prospectively compared MRD assessment in 158 blood samples of 74 patients with CLL after stem cell transplantation (SCT) using four-color flow cytometry (MRD flow) in parallel with consensus IgH-PCR and ASO IgH real-time PCR (ASO IgH RQ-PCR). In 25 out of 106 samples (23.6%) with a polyclonal consensus IgH-PCR pattern, MRD flow still detected CLL cells, proving higher sensitivity of flow cytometry over PCR-genescanning with consensus IgH-primers. Of 92 samples, 14 (15.2%) analyzed in parallel by MRD flow and by ASO IgH RQ-PCR were negative by our flow cytometric assay but positive by PCR, thus demonstrating superior sensitivity of RQ-PCR with ASO primers. Quantitative MRD levels measured by both methods correlated well (r=0.93). MRD detection by flow and ASO IgH RQ-PCR were equally suitable to monitor MRD kinetics after allogeneic SCT, but the PCR method detected impending relapses after autologous SCT earlier. An analysis of factors that influence sensitivity and specificity of flow cytometry for MRD detection allowed to devise further improvements of this technique.

Adult↗

Phase III study of all-trans retinoic acid in previously untreated patients 61 years or older with acute myeloid leukemia.

The purpose of our study was (i) to evaluate the impact of all-trans retinoic acid (ATRA) given as adjunct to chemotherapy and (ii) to compare second consolidation vs maintenance therapy in elderly patients with acute myeloid leukemia (AML). A total of 242 patients aged >or=61 years (median, 66.6 years) with AML were randomly assigned to ATRA beginning on day +3 after the initiation of chemotherapy (ATRA-arm, n=122) or no ATRA (standard-arm, n=120) in combination with induction and first consolidation therapy. A total of 61 patients in complete remission (CR) were randomly assigned to second intense consolidation (n=31) or 1-year oral maintenance therapy (n=30). After induction therapy the intention-to-treat analysis revealed a significant difference in CR rates between the ATRA- and the standard-arm (52 vs 39%; P=0.05). Event-free (EFS) and overall survival (OS) were significantly better in the ATRA-compared to the standard-arm (P=0.03 and 0.01, respectively). OS after second randomization was significantly better for patients assigned to intensive consolidation therapy (P<0.001). The multivariate model for survival revealed lactate dehydrogenase, cytogenetic risk group, age, and first and second randomization as prognostic variables. In conclusion, the addition of ATRA to induction and consolidation therapy may improve CR rate, EFS and OS in elderly patients with AML.

Acute Disease↗

DNA microarray analysis in malignant lymphomas.

Recently, DNA microarray technology has opened new avenues for the understanding of lymphomas. By hybridization of cDNA to arrays containing >10,000 different DNA fragments, this approach allows the simultaneous evaluation of the mRNA expression of thousands of genes in a single experiment. Using sophisticated bioinformatic tools, the huge amount of raw data can be clustered resulting in (1) tumor subclassification, (2) identification of pathogenetically relevant genes, or (3) biological predictors for the clinical course. This approach already has provided novel insights into different entities of B-cell non-Hodgkin's lymphomas. Genomic DNA chip hybridization (matrix-CGH) is a complementary approach focussing on genomic aberrations. In this review, we discuss the impact of this new technology both with regard to methodological aspects as well as to novel findings influencing our understanding of lymphomas.

Gene Expression Profiling↗

Transfusion-free reduced-intensity conditioned allogeneic stem cell transplantation in a Jehovah's witness.

With an estimated 6000000 Jehovah's witnesses worldwide, haematologists may encounter patients who decline blood transfusions as a matter of personal belief. Here, we describe the first case of a transfusion-free allogeneic stem cell transplant (SCT) in a Jehovah's witness with CML. The patient underwent HLA-identical peripheral blood SCT after reduced-intensity conditioning with total body irradiation and fludarabine. Conditioning and the period after transplantation were uneventful, complete donor chimerism was achieved and the patient continues to be in molecular remission without significant chronic graft-versus-host disease. When treating Jehovah's witnesses with diseases that may be cured by allogeneic SCT, this approach should be kept in mind.

Adult↗

Risk-adapted postremission therapy in acute myeloid leukemia: results of the German multicenter AML HD93 treatment trial.

The objective of the AML HD93 treatment trial was to evaluate the outcome in young adults with acute myeloid leukemia (AML) after postremission therapy was stratified according to cytogenetically defined risk. The rationales for the study design were based (i) on previous favorable results with high-dose cytarabine in AML with t(8;21), inv/t(16q22) and in AML with normal karyotype, and ii) on encouraging results obtained in several phase II trials using autologous stem cell transplantation (SCT). Between July 1993 and January 1998, 223 eligible patients, 16-60 years of age with newly diagnosed AML other than French-American-British type M3/M3v, were entered into the trial. Risk groups were defined as follows: low risk: t(8;21) or inv/t(16q22); intermediate risk: normal karyotype; high risk: all other chromosomal abnormalities. Following intensive double induction therapy with idarubicin, cytarabine and etoposide, all patients in complete remission (CR) received a first consolidation therapy with high-dose cytarabine and mitoxantrone (HAM). A second consolidation therapy was stratified according to the risk group: low risk: HAM; intermediate risk: related allogeneic SCT or sequential HAM; high risk: related allogeneic or autologous SCT. Double induction therapy resulted in a high CR rate of 74.5%, and 90% of the responding patients were eligible for consolidation therapy. Survival for all 223 trial entrants was 40%, and for the 166 patients who entered CR, disease-free (DFS) and overall survival were 40 and 51% after 5 years, respectively. Within the low-, intermediate- and high-risk groups, DFS and survival after 5 years were 62.5 and 87, 40 and 49 and 17 and 26% respectively, without advantage for allogeneic transplantation in the intermediate- and high-risk groups. Postremission therapy-related mortality was 0, 7 and 14%, respectively. This study demonstrates the feasibility of cytogenetically defined risk-adapted consolidation therapy. The overall trial results are at least equivalent to those of published trials supporting the risk-adapted treatment strategy.

Acute Disease↗

Initial results in the assessment of multiple myeloma using 18F-FDG PET.

This prospective study was undertaken to investigate the appearance of multiple myeloma on fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET). Furthermore, the accuracy of FDG-PET in detecting myeloma lesions and its influence on patient management were evaluated. Forty-three patients with known multiple myeloma (n=28) or solitary plasmacytoma (n=15) underwent FDG-PET. The results of routinely performed radiographs and of scans obtained using all available imaging modalities (MRI, CT), as well as the clinical course, were used for verification of detected lesions. Focally increased tracer uptake was observed in 38 of 41 known osteolytic bone lesions (sensitivity 92.7%) in 23 patients. In addition, 71 further bone lesions which were negative on radiographs were detected in 14 patients. Twenty-six (36.6%) of these lesions could be confirmed in ten patients. As a result of FDG-PET imaging, clinical management was influenced in five (14.0%) patients. The positive predictive value for active disease was 100% in patients with focal or mixed focal/diffuse skeletal FDG uptake and 75% in patients with diffuse bone marrow uptake. Depending on the interpretation of the PET scans in patients with diffuse bone marrow uptake, the sensitivity ranged from 83.8% to 91.9% and the specificity from 83.3% to 100%. FDG-PET thus proved highly accurate in detecting multiple myeloma, and revealed a greater extent of disease than routine radiographs in 14 of 23 (60.9%) patients who had osteolytic bone lesions. FDG-PET might contribute to the initial staging of solitary plasmacytoma.

Adult↗

Less intense conditioning with fludarabine, cyclophosphamide, idarubicin and etoposide (FCIE) followed by allogeneic unselected peripheral blood stem cell transplantation in elderly patients with leukemia.

The objective of this study was to assess toxicity and feasibility of achieving engraftment of allogeneic blood progenitor cells following nonmyeloablative conditioning according to the FCIE protocol (fludarabine 25 mg/m(2)/day, days -7 to -3; cyclophosphamide 200 mg/m(2)/day, days -7 to -3; idarubicin 12 mg/m(2)/day, days -7 to -5; etoposide 250 mg/m(2)/day, days -4 to -3) in elderly patients with leukemia. Eleven patients were included in the study: six patients with acute myeloid leukemia (AML) in complete remission (CR); three patients with refractory or relapsed AML; one patient with chronic myeloid leukemia; one patient with acute lymphoblastic leukemia. The median age of the patients was 62 years. All patients received blood progenitor cells from an HLA-identical sibling with 8.8 x 10(6) CD34(+) cells/kg (median; range 4.7 to 26.2 x 10(6)/kg) and 5.5 x 10(8) CD3(+)cells/kg (median; range 4.5 to 7.9 x 10(8)/kg). Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and three courses of methotrexate. The median duration of white blood cell counts <1 x 10(9)/l was 17 days and of platelet counts <50 x 10(9)/l 20 days. In two patients acute GVHD grade I occurred. Nine of 10 patients analyzed developed mixed chimerism. Of seven patients transplanted in CR, three remained in CR 19 to 31 months after transplantation. Three patients with refractory leukemia did not achieve CR, while the patient with relapsed AML achieved a 3rd CR. After a median follow-up time of 22 months, chronic GVHD was mild and limited. The data from this pilot study in elderly patients with leukemia show that the combination of primarily immunosuppressive (FC) and antileukemic (IE) drugs for nonmyeloablative conditioning has moderate nonhematological toxicity and allows engraftment of allogeneic blood progenitor cells.

Adult↗

Genetics of chronic lymphocytic leukemia: genomic aberrations and V(H) gene mutation status in pathogenesis and clinical course.

The genetic characterization of chronic lymphocytic leukemia (CLL) has made significant progress over the past few years. While conventional cytogenetic analyses only detected chromosome aberrations in 40-50% of cases, new molecular cytogenetic methods, such as fluorescence in situ hybridization (FISH), have greatly enhanced our ability to detect chromosomal abnormalities in CLL. Today, genomic aberrations are detected in over 80% of CLL cases. Genes potentially involved in the pathogenesis were identified with ATM in a subset of cases with 11q deletion and p53 in cases with 17p13 deletion. For the most frequent aberration, the deletion 13q14, candidate genes have been isolated. Genetic subgroups with distinct clinical features have been identified. 11q deletion is associated with marked lymphadenopathy and rapid disease progression. 17p deletion predicts for treatment failure with alkylating agents, as well as fludarabine and short survival times. In multivariate analysis 11q and 17p deletions provided independent prognostic information. Recently, another important issue of genetic risk classification in CLL was identified with the mutation status of the immunoglobulin variable heavy chain genes (V(H)). CLL cases with unmutated V(H) show more rapid disease progression and shorter survival times. Whether CD38 expression can serve as a surrogate marker for V(H) mutation status is currently discussed controversially. V(H) mutation status and genomic abnormalities, such as 17p and 11q deletion, have recently been shown to be related to each other, but were of independent prognostic information in multivariate analysis. Moreover, genomic aberrations and V(H) mutation status appear to give prognostic information irrespective of the clinical stage and may therefore allow a risk assessment for individual patients early in the course of their disease.

Chromosome Aberrations↗

Rhenium 188-labeled anti-CD66 (a, b, c, e) monoclonal antibody to intensify the conditioning regimen prior to stem cell transplantation for patients with high-risk acute myeloid leukemia or myelodysplastic syndrome: results of a phase I-II study.

The conditioning regimen prior to stem cell transplantation in 36 patients with high-risk acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) was intensified by treating patients with a rhenium 188-labeled anti-CD66 monoclonal antibody. Dosimetry was performed prior to therapy, and a favorable dosimetry was observed in all cases. Radioimmunotherapy with the labeled antibody provided a mean of 15.3 Gy of additional radiation to the marrow; the kidney was the normal organ receiving the highest dose of supplemental radiation (mean 7.4 Gy). Radioimmunotherapy was followed by standard full-dose conditioning with total body irradiation (12 Gy) or busulfan and high-dose cyclophosphamide with or without thiotepa. Patients subsequently received a T-cell-depleted allogeneic graft from a HLA-identical family donor (n = 15) or an alternative donor (n = 17). In 4 patients without an allogeneic donor, an unmanipulated autologous graft was used. Infusion-related toxicity due to the labeled antibody was minimal, and no increase in treatment-related mortality due to the radioimmunoconjugate was observed. Day +30 and day +100 mortalities were 3% and 6%, respectively, and after a median follow-up of 18 months treatment-related mortality was 22%. Late renal toxicity was observed in 17% of patients. The relapse rate of 15 patients undergoing transplantation in first CR (complete remission) or second CR was 20%; 21 patients not in remission at the time of transplantation had a 30% relapse rate. (Blood. 2001;98:565-572)

Acute Disease↗

Clinical relevance of genomic aberrations in homogeneously treated high-risk stage II/III breast cancer patients.

Little is known about the prognostic impact of chromosome aberrations in breast cancer. The aim of our study was to determine whether genomic aberrations of prognostic relevance can be identified in the context of a clinical study using molecular cytogenetics. Paraffin-embedded tumor samples of 44 patients with high-risk stage II/III breast cancer were analyzed by comparative genomic hybridization. All patients received identical therapy including dose-escalated chemotherapy followed by peripheral blood stem cell transplantation. The most frequent chromosomal aberrations were gains on chromosome arms 17q (24 cases), 1q (21 cases), 8q (17 cases), 20q (13 cases), 6p (9 cases) as well as losses on chromosome arms 13q (25 cases), 11q (20 cases), 5q (11 cases), 6q (11 cases), 9p (10 cases), 18q (10 cases), 8p (9 cases) and 16q (9 cases). In univariate analysis, the correlation with the clinical outcome revealed a higher risk for patients with tumors exhibiting 13q losses and a reduced risk for tumors exhibiting 16q losses (p = 0.020), 6q losses (p = 0.041) and estrogen-receptor positivity (0.051). In multivariate analysis using the Cox model, only the loss of 16q exhibited borderline significance (p = 0.065). These data show that comparative genomic hybridization can be performed in the context of a clinical trial. In our subgroup of high-risk breast cancer patients, chromosomal aberrations were valuable prognostic parameters.

Adult↗

B-cell neoplasia associated gene with multiple splicing (BCMS): the candidate B-CLL gene on 13q14 comprises more than 560 kb covering all critical regions.

Deletions in chromosomal band 13q14.3 occur in >50% of B-cell chronic lymphocytic leukemias (B-CLL) and mantle cell lymphoma, indicating the localization of a tumor suppressor gene involved in the pathomechanism of these diseases. Within a 400 kb recurrently deleted segment at least two minimally deleted subregions had been reported. For the two genes residing in the proximal subregion, initially named LEU1 and LEU2, a pathogenic role has not yet been established. We report here that LEU1 is only a small portion of a large gene, which spans all previously reported critical subregions including the distal subregion. This gene, designated B-cell neoplasia-associated gene with multiple splicing (BCMS), is composed of at least 50 exons spanning >or=560 kb of genomic DNA and is expressed in more than 20 RNA splicing variants. While tissue-specific expression of RNA variants was observed, there was no evidence for the expression of a variant specific for B-CLL. Sequence analysis of the RNA variants suggests that BCMS transcripts belong to the group of non-coding RNAs. The alignment of the gene with all critical subregions provides a strong argument for BCMS being the most likely candidate for the tumor suppressor gene in 13q14 involved in the leukemogenesis of B-CLL. Due to the limited understanding of functional RNAs, however, it remains difficult to prove the pathogenic role of BCMS.

Alternative Splicing↗

CDNA microarray gene expression analysis of B-cell chronic lymphocytic leukemia proposes potential new prognostic markers involved in lymphocyte trafficking.

Human cancer is characterized by complex molecular perturbations leading to variable clinical behavior, often even in single-disease entities. We performed a feasibility study systematically comparing large-scale gene expression profiles with clinical features in human B-cell chronic lymphocytic leukemia (B-CLL). cDNA microarrays were employed to determine the expression levels of 1,024 selected genes in 54 peripheral blood lymphocyte samples obtained from patients with B-CLL. Statistical analyses were applied to correlate the expression profiles with a number of clinical parameters including patient survival and disease staging. We were able to identify genes whose expression levels significantly correlated with patient survival and/or with clinical staging. Most of these genes code either for cell adhesion molecules (L-selectin, integrin-beta2) or for factors inducing cell adhesion molecules (IL-1beta, IL-8, EGR1), suggesting that prognosis of this disease may be related to a defect in lymphocyte trafficking. This report demonstrates the feasibility of a systematic integration of large-scale gene expression profiles with clinical data as a general approach for dissecting human diseases.

Adult↗

Correlation of clinical data with proteomics profiles in 24 patients with B-cell chronic lymphocytic leukemia.

The development of human cancer is caused by complex molecular perturbations leading to variable clinical behavior often even in single disease entities. To prove that expression profiling on the protein level can be correlated with clinical data we systematically compared in a pilot study the protein expression patterns obtained by 2-dimensional gel electrophoresis with clinical features in human B-cell chronic lymphocytic leukemia (B-CLL), a disease characterized by broad clinical variability. Statistical methods were devised to analyze the spot pattern from 24 patient samples. This analysis allowed the identification of proteins that clearly discriminated between the patient groups with defined chromosomal characteristics or whose expression levels did correlate with clinical parameters such as patient survival. This report demonstrates that the correlation of large-scale protein expression profiles with clinical data can be used to gain new insights into molecular aspects of a disease. The data described here show that B-CLL patient populations with shorter survival times exhibit changed levels of redox enzymes, heat shock protein 27 and protein disulfide isomerase. These molecules may be potentially involved in drug resistance.

Humans↗

Gain of chromosome arm 9p is characteristic of primary mediastinal B-cell lymphoma (MBL): comprehensive molecular cytogenetic analysis and presentation of a novel MBL cell line.

Primary mediastinal B-cell lymphoma (MBL) is an aggressive Non-Hodgkin's Lymphoma, which has been recognized as a distinct disease entity. We performed a comprehensive molecular cytogenetic study analyzing 43 MBLs. By comparative genomic hybridization (CGH), the most common aberrations were gains of chromosome arms 9p and Xq, which were present in 56% and 40% of cases, respectively. Based on the limited resolution of CGH, this technique may underestimate the real incidence of aberrations. Therefore, we also did an interphase cytogenetic study with eight DNA probes mapping to chromosome regions frequently altered in B-cell lymphomas. With this approach, both 9p and Xq gains were found in more than 70% of cases (75% and 87%, respectively). The findings were compared with results obtained in 308 other B-cell lymphomas. Gains in 9p were identified in only six of the 308 cases, and only one of these lymphomas with 9p gains was not primarily extranodal in origin (P < 10-(20) for CGH data and P < 10-(11) for fluorescence in situ hybridization data). We also present a novel MBL cell line, MedB-1, which carries the genetic aberrations characteristic of this entity.

Adolescent↗

Molecular-cytogenetic comparison of mucosa-associated marginal zone B-cell lymphoma and large B-cell lymphoma arising in the gastro-intestinal tract.

Extranodal B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type may represent a model of lymphoma progression, because a small cell component frequently occurs in the large cell variants. We studied 52 extranodal B-cell lymphomas: 18 extranodal marginal zone B-cell lymphomas of MALT type (MZBL,MT), 7 MZBL,MT of the gastro-intestinal tract with a diffuse large B-cell component (giMZBLplusLBCL), and 27 diffuse large B-cell lymphomas of the gastro-intestinal tract without small cell component (giLBCL). Analytical techniques were comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). The translocation t(11;18) was found as the sole aberration in two MZBL,MT only. In contrast to this, t(11;18)-negative MZBL,MT were characterized by frequent gains on chromosome 3 and DNA amplifications on 2p13-p15. Furthermore, we found a clonal lymphoma progression from the small to the large cell component with accumulation of gains and losses of chromosomal material in the large cell component in giMZBLplusLBCL. Aberrations overlapping with MZBL,MT and giMZBLplusLBCL included losses on chromosome 13, amplifications of the REL proto-oncogene, or gains on chromosome 12. In addition, the large cell component revealed gains on 8q24, including amplifications of the MYC proto-oncogene, and losses on 2q. The giLBCL had frequent gains on chromosomes 12 and 9, as well as on 11q, and losses on 6q. We conclude that, based on the distinctive and partly overlapping patterns of genetic aberrations, MALT lymphomas can be divided into different genetic subgroups.

Chromosome Aberrations↗