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Featured researches published by Barbara Hildebrandt.


Journal of Clinical Oncology | 2007

Time-Dependent Prognostic Scoring System for Predicting Survival and Leukemic Evolution in Myelodysplastic Syndromes

Luca Malcovati; Ulrich Germing; Andrea Kuendgen; Matteo G. Della Porta; Cristiana Pascutto; Rosangela Invernizzi; Aristoteles Giagounidis; Barbara Hildebrandt; Paolo Bernasconi; S. Knipp; Corinna Strupp; Mario Lazzarino; Carlo Aul; Mario Cazzola

PURPOSE The aims of this study were to identify the most significant prognostic factors in myelodysplastic syndromes (MDS) taking into account both their values at clinical onset and their changes in time and to develop a dynamic model for predicting survival and leukemic evolution that can be applied at any time during the course of the disease. PATIENTS AND METHODS We studied a learning cohort of 426 MDS patients diagnosed at the Department of Hematology, San Matteo Hospital, Pavia, Italy, between 1992 and 2004, and a validation cohort of 739 patients diagnosed at the Heinrich-Heine-University Hospital, Düsseldorf, Germany, between 1982 and 2003. All patients were reclassified according to WHO criteria. Univariable and multivariable analyses were performed using Cox models with time-dependent covariates. RESULTS The most important variables for the prognostic model were WHO subgroups, karyotype, and transfusion requirement. We defined a WHO classification-based prognostic scoring system (WPSS) that was able to classify patients into five risk groups showing different survivals (median survival from 12 to 103 months) and probabilities of leukemic evolution (P < .001). WPSS was shown to predict survival and leukemia progression at any time during follow-up (P < .001), and its prognostic value was confirmed in the validation cohort. CONCLUSION WPSS is a dynamic prognostic scoring system that provides an accurate prediction of survival and risk of leukemic evolution in MDS patients at any time during the course of their disease. This time-dependent system seems particularly useful in lower risk patients and may be used for implementing risk-adapted treatment strategies.


Blood | 2007

New insights into the prognostic impact of the karyotype in MDS and correlation with subtypes: evidence from a core dataset of 2124 patients

Detlef Haase; Ulrich Germing; Julie Schanz; Michael Pfeilstöcker; Thomas Nösslinger; Barbara Hildebrandt; Andrea Kündgen; Michael Lübbert; Regina Kunzmann; Aristoteles Giagounidis; Carlo Aul; Lorenz Trümper; Otto Krieger; Reinhard Stauder; Thomas Müller; Friedrich Wimazal; Peter Valent; Christa Fonatsch; Christian Steidl

We have generated a large, unique database that includes morphologic, clinical, cytogenetic, and follow-up data from 2124 patients with myelodysplastic syndromes (MDSs) at 4 institutions in Austria and 4 in Germany. Cytogenetic analyses were successfully performed in 2072 (97.6%) patients, revealing clonal abnormalities in 1084 (52.3%) patients. Numeric and structural chromosomal abnormalities were documented for each patient and subdivided further according to the number of additional abnormalities. Thus, 684 different cytogenetic categories were identified. The impact of the karyotype on the natural course of the disease was studied in 1286 patients treated with supportive care only. Median survival was 53.4 months for patients with normal karyotypes (n = 612) and 8.7 months for those with complex anomalies (n = 166). A total of 13 rare abnormalities were identified with good (+1/+1q, t(1q), t(7q), del(9q), del(12p), chromosome 15 anomalies, t(17q), monosomy 21, trisomy 21, and -X), intermediate (del(11q), chromosome 19 anomalies), or poor (t(5q)) prognostic impact, respectively. The prognostic relevance of additional abnormalities varied considerably depending on the chromosomes affected. For all World Health Organization (WHO) and French-American-British (FAB) classification system subtypes, the karyotype provided additional prognostic information. Our analyses offer new insights into the prognostic significance of rare chromosomal abnormalities and specific karyotypic combinations in MDS.


Journal of Clinical Oncology | 2012

New Comprehensive Cytogenetic Scoring System for Primary Myelodysplastic Syndromes (MDS) and Oligoblastic Acute Myeloid Leukemia After MDS Derived From an International Database Merge

Julie Schanz; Heinz Tüchler; Francesc Solé; Mar Mallo; Elisa Luño; José Cervera; Isabel Granada; Barbara Hildebrandt; Marilyn L. Slovak; Kazuma Ohyashiki; Christian Steidl; Christa Fonatsch; Michael Pfeilstöcker; Thomas Nösslinger; Peter Valent; Aristoteles Giagounidis; Carlo Aul; Michael Lübbert; Reinhard Stauder; Otto Krieger; Guillermo Garcia-Manero; Stefan Faderl; Sherry Pierce; Michelle M. Le Beau; John M. Bennett; Peter L. Greenberg; Ulrich Germing; Detlef Haase

PURPOSE The karyotype is a strong independent prognostic factor in myelodysplastic syndromes (MDS). Since the implementation of the International Prognostic Scoring System (IPSS) in 1997, knowledge concerning the prognostic impact of abnormalities has increased substantially. The present study proposes a new and comprehensive cytogenetic scoring system based on an international data collection of 2,902 patients. PATIENTS AND METHODS Patients were included from the German-Austrian MDS Study Group (n = 1,193), the International MDS Risk Analysis Workshop (n = 816), the Spanish Hematological Cytogenetics Working Group (n = 849), and the International Working Group on MDS Cytogenetics (n = 44) databases. Patients with primary MDS and oligoblastic acute myeloid leukemia (AML) after MDS treated with supportive care only were evaluated for overall survival (OS) and AML evolution. Internal validation by bootstrap analysis and external validation in an independent patient cohort were performed to confirm the results. RESULTS In total, 19 cytogenetic categories were defined, providing clear prognostic classification in 91% of all patients. The abnormalities were classified into five prognostic subgroups (P < .001): very good (median OS, 61 months; hazard ratio [HR], 0.5; n = 81); good (49 months; HR, 1.0 [reference category]; n = 1,809); intermediate (26 months; HR, 1.6; n = 529); poor (16 months; HR, 2.6; n = 148); and very poor (6 months; HR, 4.2; n = 187). The internal and external validations confirmed the results of the score. CONCLUSION In conclusion, these data should contribute to the ongoing efforts to update the IPSS by refining the cytogenetic risk categories.


Cancer | 2006

The histone deacetylase (HDAC) inhibitor valproic acid as monotherapy or in combination with all-trans retinoic acid in patients with acute myeloid leukemia.

Andrea Kuendgen; Mathias Schmid; Richard Schlenk; Sabine Knipp; Barbara Hildebrandt; Christian Steidl; Ulrich Germing; Rainer Haas; Hartmut Dohner; Norbert Gattermann

Valproic acid (VPA) inhibits histone deacetylase activity and, synergizing with all‐trans retinoic acid (ATRA), achieves differentiation induction of myeloid blast cells in vitro.


Leukemia | 2004

Clinical, morphological, cytogenetic, and prognostic features of patients with myelodysplastic syndromes and del(5q) including band q31

Aristoteles Giagounidis; Ulrich Germing; S Haase; Barbara Hildebrandt; Brigitte Schlegelberger; Claudia Schoch; Ludwig Wilkens; M Heinsch; H Willems; M. Aivado; Carlo Aul

We analyzed data of 76 consecutive patients with myelodysplastic syndrome (MDS) and isolated del(5q) (n=66) or del(5q) plus one additional chromosomal abnormality (n=10) included in our MDS database over the last 26 years. The median age of our patient population was 66.8 years. The male to female ratio was 1:1.7. In all, 14 patients (18%) had advanced MDS with an increased medullary blast count. A total of 17 patients (22%) had significant dysplasia in the nonmegakaryocytic cell lines. Nearly half of the study population showed erythroid hypoplasia in the bone marrow. The projected median survival of patients with isolated del(5q) is 146 months for a median follow-up of 67 months. Patients with an increased medullary blast count and those with an additional chromosomal abnormality have a significantly shorter overall survival (24 and 45 months, respectively) than patients with isolated del(5q). We did not find survival differences for different cytogenetic breakpoints, nor did the amount of dysplasia have an impact on survival in our population. In total, 29 patients have died. Deaths occurred primarily due to transformation into acute leukemia, infection, or cardiac failure. Our data support the current definition of a separate entity of MDS with del(5q) that has been suggested by the World Health Organization.


Annals of Hematology | 2005

Results of a phase 2 study of valproic acid alone or in combination with all-trans retinoic acid in 75 patients with myelodysplastic syndrome and relapsed or refractory acute myeloid leukemia

Andrea Kuendgen; Sabine Knipp; Frank Fox; Corinna Strupp; Barbara Hildebrandt; Christian Steidl; Ulrich Germing; Rainer Haas; Norbert Gattermann

Valproic acid (VPA) inhibits histone deacetylase activity and induces differentiation of acute myeloid leukemia (AML) blasts in vitro. We observed clinical responses to VPA in patients with myelodysplastic syndrome (MDS) and AML. Here, we report follow-up data on 75 patients. Of these, 66 were started on VPA monotherapy, with later addition of all-trans retinoic acid (ATRA) in patients who did not respond or relapsed. Nine patients were treated with VPA + ATRA from the start. Median treatment duration was 4 months for VPA and 2 months for ATRA. Hematological improvement, according to international working group criteria for MDS, was observed in 18 patients (24%). Median response duration was 4 months. ATRA exerted no additional effect in patients receiving the combination from the start or benefited primary VPA nonresponders. However, of ten VPA responders who relapsed, four achieved a second response after addition of ATRA. Response rates were strongly dependent on disease type according to WHO classification. We found a response rate of 52% in MDS patients with a normal blast count (refractory sideroblastic anemia, refractory cytopenia with multilineage dysplasia, and refractory sideroblastic cytopenia with multilineage dysplasia). The response rate was 6% in refractory anemia with excess blasts (I + II), 16% in AML, and 0% in chronic myelomonocytic leukemia. Bone marrow blast count was the only variable that predicted responses. We conclude that VPA is clinically useful in low-risk MDS. For patients with high-risk MDS, VPA may be combined with chemotherapy or demethylating drugs. If patients relapse after an initial response to VPA, ATRA has the potential to induce a prolonged second response.


Leukemia | 2005

Refinement of the international prognostic scoring system (IPSS) by including LDH as an additional prognostic variable to improve risk assessment in patients with primary myelodysplastic syndromes (MDS)

Ulrich Germing; Barbara Hildebrandt; Michael Pfeilstöcker; Thomas Nösslinger; Peter Valent; Christa Fonatsch; Michael Lübbert; Detlef Haase; Christian Steidl; Otto Krieger; Reinhard Stauder; A. Giagounidis; C Strupp; Andrea Kündgen; T Mueller; Rainer Haas; Norbert Gattermann; Carlo Aul

The international prognostic scoring system (IPSS) is considered the gold standard for risk assessment in primary myelodysplastic syndromes (MDS). This score includes several prognostic factors except serum lactate dehydrogenase (LDH). We evaluated the prognostic power of LDH as an additional variable in IPSS-based risk assessment. For this purpose, a total of 892 patients with primary MDS registered by the Austrian–German cooperative MDS study group was analyzed retrospectively. Multivariate analysis confirmed the value of established parameters such as medullary blasts, karyotype and peripheral cell counts and showed that elevated LDH was associated with decreased overall survival (P<0.00005) and increased risk of AML development (P<0.00005), independent of the system used to classify MDS (FAB or WHO). Moreover, elevated LDH was found to be a significant predictor of poor survival within each IPSS risk group and within each FAB group except RAEB-T. To exploit these results for refined prognostication, each IPSS risk group was split into two separate categories (A=normal LDH vs B=elevated LDH). Using this LDH-assisted approach, it was possible to identify MDS patients with unfavorable prognosis within the low and intermediate IPSS risk groups. We propose that the IPSS+LDH score should improve clinical decision-making and facilitate proper risk stratification in clinical trials.


Blood | 2013

Development and validation of a prognostic scoring system for patients with chronic myelomonocytic leukemia

Esperanza Such; Ulrich Germing; Luca Malcovati; José Cervera; Andrea Kuendgen; Matteo G. Della Porta; Benet Nomdedeu; Leonor Arenillas; Elisa Luño; Blanca Xicoy; M.L. Amigo; David Valcárcel; Kathrin Nachtkamp; Ilaria Ambaglio; Barbara Hildebrandt; Ignacio Lorenzo; Mario Cazzola; Guillermo Sanz

The natural course of chronic myelomonocytic leukemia (CMML) is highly variable but a widely accepted prognostic scoring system for patients with CMML is not available. The main aim of this study was to develop a new CMML-specific prognostic scoring system (CPSS) in a large series of 558 patients with CMML (training cohort, Spanish Group of Myelodysplastic Syndromes) and to validate it in an independent series of 274 patients (validation cohort, Heinrich Heine University Hospital, Düsseldorf, Germany, and San Matteo Hospital, Pavia, Italy). The most relevant variables for overall survival (OS) and evolution to acute myeloblastic leukemia (AML) were FAB and WHO CMML subtypes, CMML-specific cytogenetic risk classification, and red blood cell (RBC) transfusion dependency. CPSS was able to segregate patients into 4 clearly different risk groups for OS (P < .001) and risk of AML evolution (P < .001) and its predictive capability was confirmed in the validation cohort. An alternative CPSS with hemoglobin instead of RBC transfusion dependency offered almost identical prognostic capability. This study confirms the prognostic impact of FAB and WHO subtypes, recognizes the importance of RBC transfusion dependency and cytogenetics, and offers a simple and powerful CPSS for accurately assessing prognosis and planning therapy in patients with CMML.


Journal of Clinical Oncology | 2011

Coalesced Multicentric Analysis of 2,351 Patients With Myelodysplastic Syndromes Indicates an Underestimation of Poor-Risk Cytogenetics of Myelodysplastic Syndromes in the International Prognostic Scoring System

Julie Schanz; Christian Steidl; Christa Fonatsch; Michael Pfeilstöcker; Thomas Nösslinger; Heinz Tuechler; Peter Valent; Barbara Hildebrandt; Aristoteles Giagounidis; Carlo Aul; Michael Lübbert; Reinhard Stauder; Otto Krieger; Guillermo Garcia-Manero; Hagop Kantarjian; Ulrich Germing; Detlef Haase; Elihu H. Estey

PURPOSE The International Prognostic Scoring System (IPSS) remains the most commonly used system for risk classification in myelodysplastic syndromes (MDSs). The IPSS gives more weight to blast count than to cytogenetics. However, previous publications suggested that cytogenetics are underweighted in the IPSS. Here we investigate the prognostic impact of cytogenetic subgroups compared with that of bone marrow blast count in a large, multicentric, international patient cohort. PATIENTS AND METHODS In total, 2,351 patients with MDS who have records in the German-Austrian and the MD Anderson Cancer Center databases were included and analyzed in univariate and multivariate models regarding overall survival and risk of transformation to acute myeloid leukemia (AML). The data were analyzed separately for patients treated with supportive care without specific therapy, with AML-like chemotherapy, or with other therapy regimens (low-dose chemotherapy, demethylating agents, immune modulating agents, valproic acid, and cyclosporine). RESULTS The prognostic impact of poor-risk cytogenetic findings (as defined by the IPSS classification) on overall survival was as unfavorable as an increased (> 20%) blast count. The hazard ratio (compared with an abnormal karyotype or a bone marrow blast count < 5%) was 3.3 for poor-risk cytogenetics, 4.8 for complex abnormalities harboring chromosomes 5 and/or 7, and 3.1 for a blast count of 21% to 30% (P < .01 for all categories). The predictive power of the IPSS cytogenetic subgroups was unaffected by type of therapy given. CONCLUSION The independent prognostic impact of poor-risk cytogenetics on overall survival is equivalent to the impact of high blast counts. This finding should be considered in the upcoming revision of the IPSS.


Cancer Research | 2009

Hyperactivation of the Insulin-like Growth Factor Receptor I Signaling Pathway Is an Essential Event for Cisplatin Resistance of Ovarian Cancer Cells

Niels Eckstein; Kati Servan; Barbara Hildebrandt; Anne Pölitz; Georg von Jonquieres; Sybille Wolf-Kümmeth; Inge Napierski; Alexandra Hamacher; Matthias U. Kassack; Jan Budczies; Manfred Beier; Manfred Dietel; Brigitte Royer-Pokora; Carsten Denkert; Hans-Dieter Royer

Platinum plays a central role in the therapy of ovarian cancer, and the emergence of platinum resistance is a major obstacle for clinical management of the disease. We treated A2780 ovarian cancer cells by weekly cycles of cisplatin over a period of 6 months and unveiled that enhanced insulin-like growth factor I receptor (IGF-IR) expression and autocrine IGF-I are associated with hyperactivation of the IGF-IR and phosphatidylinositol-3-OH kinase (PI3K) pathways in cisplatin-resistant cells. IGF-IR expression levels increased during treatment cycles and correlated with cisplatin resistance. Purified IGF-I induced cisplatin resistance in diverse ovarian cancer cell lines, and small molecule inhibitors proved that IGF-IR and PI3K are essential for cisplatin resistance. Similar results were obtained with BG-1 ovarian cancer cells. Cytogenetic and array comparative genomic hybridization analyses revealed selection and de novo formation of chromosomal alterations during resistance development. An analysis of gene expression profiles of primary ovarian carcinomas identified the regulatory subunit PIK3R2 of PI3-kinase as a significant negative prognosis factor for ovarian cancer. We conclude that targeting the IGF-IR and the PI3K pathways is a promising new strategy to treat cisplatin-resistant ovarian carcinomas.

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Ulrich Germing

University of Düsseldorf

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Carlo Aul

University of Düsseldorf

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Andrea Kuendgen

University of Düsseldorf

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Detlef Haase

University of Göttingen

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Corinna Strupp

University of Düsseldorf

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Rainer Haas

Ludwig Maximilian University of Munich

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Julie Schanz

University of Göttingen

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Peter Valent

Medical University of Vienna

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