Christophe Ravoet
Université libre de Bruxelles
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Featured researches published by Christophe Ravoet.
British Journal of Haematology | 2001
Michael Lübbert; Pierre W. Wijermans; Regina Kunzmann; Gregor Verhoef; André Bosly; Christophe Ravoet; Marc André; Augustin Ferrant
Decitabine (5‐aza‐2′‐deoxycytidine) acts as a powerful demethylating agent in vitro. Clinically, low‐dose decitabine ameliorates cytopenias including induction of trilineage responses in ≈50% of patients with high‐risk myelodysplastic syndrome (MDS). We examined the incidence and kinetics of cytogenetic responses to decitabine in these patients. Of 115 successfully karyotyped patients, 61 (53%) had clonal chromosomal abnormalities prior to treatment. Major cytogenetic responses were observed in 19 patients (31% of those with abnormal cytogenetics, 17% of all patients by intention‐to‐treat) after a median of three courses (range, 2–6) until best cytogenetic response. Progressive decrease of the abnormal clone over time was also determined using fluorescence in situ hybridization (FISH) analysis in two patients. Median duration of cytogenetic responses was 7·5 months (range, 3–15). Analysis of response by the International Prognostic Scoring System (IPSS) cytogenetic risk groups revealed three out of five cytogenetic responses (60%) in the IPSS ‘low‐risk’ group, 6 out of 30 with ‘intermediate risk’ (20%) and 10 out of 26 in the ‘high‐risk’ group (38%). Median survival in these cytogenetic subgroups was 30, 8 and 13 months respectively. The relative risk of death in patients achieving a major cytogenetic response was 0·38 (95% confidence interval 0·17–0·88) compared with patients in whom the cytogenetically abnormal clone persisted (P = 0·0213). In conclusion, repeated courses of low‐dose decitabine induce cytogenetic remissions in a substantial number of elderly MDS patients with pre‐existing chromosomal abnormalites; these are associated with improved survival compared with patients in whom the cytogenetically abnormal clone persists. Patients with ‘high‐risk’ chromosomal abnormalities may particularly benefit from this treatment.
Blood | 2009
Lionel Ades; Simone Boehrer; Thomas Prebet; Odile Beyne-Rauzy; Laurence Legros; Christophe Ravoet; Francois Dreyfus; Aspasia Stamatoullas; Marie Pierre Chaury; Jacques Delaunay; Guy Laurent; Norbert Vey; Sara Burcheri; Rose-Marie Mbida; Natacha Hoarau; Claude Gardin; Pierre Fenaux
Higher-risk MDS with del5q carry a poor prognosis. In this phase 2 trial, 47 patients with higher-risk MDS received lenalidomide 10 mg/day. International Prognostic Scoring System was high in 60%, intermediate-2 risk in 40%. del 5q was isolated, with one additional and more than one additional abnormality in 19%, 23%, and 58% patients, respectively. Thirteen (27%) patients achieved hematologic response, including 7 hematologic complete remission (CR) (with complete [4] or partial [3] cytogenetic response), 2 marrow CR and 4 hematologic improvement erythroid, and 12 became red blood cell (RBC) transfusion independent, for a median duration of 6.5 months. Median CR duration was 11.5 months. Six of 9 (67%) patients with isolated del 5q achieved CR, versus 1 of 11 and none of 27 patients with one or more than one additional abnormality, respectively (P < .001). Seven of 20 (35%) with initial platelets more than 100,000/mm(3) obtained CR, compared with none of the 27 with lower platelet counts less than 100,000/mm(3) (P = .001). Our data support a potential role of lenalidomide in higher-risk MDS with isolated del 5q.
Leukemia Research | 2010
Sophie Park; Charikleia Kelaidi; Rosa Sapena; D. Vassilieff; Odile Beyne-Rauzy; Valérie Coiteux; Norbert Vey; Christophe Ravoet; Stéphane Cheze; Christian Rose; Laurence Legros; Aspasia Stamatoullas; Martine Escoffre-Barbe; Agnès Guerci; M.P. Chaury; Pierre Fenaux; Francois Dreyfus
ESAs are increasingly used to treat anemia of lower risk MDS, even before RBC transfusion requirement. From a previously published patient cohort treated with ESAs, we selected 112 patients with de novo low or int-1 IPSS MDS with Hb<10 g/dl, serum EPO<500 UI/l and who had never been transfused. Erythroid response rate at 12 weeks was 63.1% (IWG 2006). In multivariate analysis, an interval between diagnosis and ESA onset<6 months, Hb level>9 g/dl, and serum EPO<100 UI/l predicted better response to ESA while shorter interval between diagnosis and ESA onset (p=0.01), lower serum EPO (p=0.04) and WHO diagnosis of RCMD-RS (p=0.03) were associated with longer response. Median interval from diagnosis to transfusion dependency was 80 months and 35 months, respectively, in patients with onset of ESA < 6 months and ≥ 6 months from diagnosis (p=0.007). Those results support early onset of ESA in lower risk MDS, to better avoid the consequences of anemia. Early introduction of ESA may also delay the need for RBC transfusions, hypothetically by slowing the disease course, but prospective studies are required to further assess this point.
Leukemia Research | 2014
Michel Delforge; Dominik Selleslag; Yves Beguin; Agnès Triffet; Philippe Mineur; Koen Theunissen; Carlos Graux; Fabienne Trullemans; Dominique Boulet; Koen Van Eygen; Lucien Noens; Jan Lemmens; Pascal Pierre; Randal D'hondt; Augustin Ferrant; Dries Deeren; Ann Van de Velde; Wim Wynendaele; Marc André; Robrecht De Bock; André Efira; Dimitri A. Breems; Anne Deweweire; Kurt Geldhof; Wim Pluymers; Amanda R. Harrington; Karen MacDonald; Ivo Abraham; Christophe Ravoet
BACKGROUND Most patients with myelodysplastic syndromes (MDS) require transfusions at the risk of iron overload and associated organ damage, and death. Emerging evidence indicates that iron chelation therapy (ICT) could reduce mortality and improve survival in transfusion-dependent MDS patients, especially those classified as International Prognostic Scoring System (IPSS) Low or Intermediate-1 (Low/Int-1). METHODS Follow-up of a retrospective study. Sample included 127 Low/Int-1 MDS patients from 28 centers in Belgium. Statistical analysis stratified by duration (≥6 versus <6 months) and quality of chelation (adequate versus weak). RESULTS Crude chelation rate was 63% but 88% among patients with serum ferritin ≥1000 μg/L. Of the 80 chelated patients, 70% were chelated adequately mainly with deferasirox (26%) or deferasirox following deferoxamine (39%). Mortality was 70% among non-chelated, 40% among chelated, 32% among patients chelated ≥6 m, and 30% among patients chelated adequately; with a trend toward reduced cardiac mortality in chelated patients. Overall, median overall survival (OS) was 10.2 years for chelated and 3.1 years for non-chelated patients (p<0.001). For patients chelated ≥6 m or patients classified as adequately chelated, median OS was 10.5 years. Mortality increased as a function of average monthly transfusion intensity (HR=1.08, p=0.04) but was lower in patients receiving adequate chelation or chelation ≥6 m (HR=0.24, p<0.001). CONCLUSION Six or more months of adequate ICT is associated with markedly better overall survival. This suggests a possible survival benefit of ICT in transfusion-dependent patients with lower-risk MDS.
Leukemia & Lymphoma | 2004
Christophe Ravoet; Sonia DeMartin; Raymonde Gerard; Michel Dehon; Marie-Odile Peny; Bénédicte Petit; Bernard Husson
In order to assess the contribution of FC to the diagnosis of lymph node disorders we retrospectively compared the pathological and the FC diagnosis made in 118 consecutive lymph node biopsies. Pathological diagnosis included non malignant conditions (n = 43), B-cell Non Hodgkin lymphoma (NHL) (n = 30), T-cell NHL (1 case), carcinoma (n = 18), Hodgkin lymphoma (HL) (n = 15), melanoma (n = 2), chronic myelocytic leukemia (n = 12), miscellaneous non-lymphoid tissues (n = 6) and undetermined conditions (n = 2). Among the 116 assessable samples, FC was in agreement with histology in 102 cases (87.9%; 95%CI = 81-93) which included 38 benign conditions (90%; 95% CI = 77-97%), 29 NHL (96.7%; 95% CI = 83-100), 18 carcinomas (100%; 95% CI = 81-100), and 12 HL (80.0%; 95% CI = 52-96). Discrepancies (14 cases) included 3 HL undiagnosed by FC and 2 granulomatous adenitis with an erroneous FC diagnosis of HL. Finally, a malignant condition was suspected only by FC in 5 cases (1 carcinoma, 2 B-cell and 2 T-cell NHL) and subsequently demonstrated by additional diagnostic procedures. In conclusion, this study confirms that FC performed on fresh lymph node samples is a powerful diagnostic tool in patients with malignant lymphoma. A few cases left undiagnosed by classical pathological analysis can be recognized by FC. Carcinoma is readily identified by FC analysis, while some benign conditions and Hodgkin lymphoma can be misdiagnosed with the use of FC, although the potential of FC to properly recognize HL is improving compared to previously reported studies. FC is a useful adjunct to pathological analysis of lymph node specimens.
Leukemia | 2007
Stef Meers; Ahmad Kasran; Louis Boon; Jan Lemmens; Christophe Ravoet; Marc Boogaerts; Gregor Verhoef; Catherine M. Verfaillie; Michel Delforge
Immune mechanisms have been shown to contribute to the process of myelodysplastic syndromes (MDS)-related bone marrow (BM) failure. The aim of this study was to evaluate the possible contribution of activated monocytes through CD40–CD40L(CD154) interactions with activated T helper cells. We demonstrated in 77 predominantly lower risk MDS patients that the CD40 receptor was expressed significantly higher on monocytes and that CD40L was expressed significantly higher on T helper cells in peripheral blood (PB) and BM. Increased levels of CD40 and CD40L were detected in the same patients. In addition, stimulation of the CD40 receptor on purified PB monocytes led to a significantly higher tumor necrosis factor alpha production in patients. Co-culture of BM mononuclear cells of 21 patients in the presence of a blocking CD40 monoclonal antibody (ch5D12) led to a significant increase in the number of colony-forming units. A correlation was seen between increased CD40 expression on monocytes with patients’ age below 60 years and with the cytogenetic abnormality trisomy 8. These results demonstrate that CD40 expression on monocytes may identify a subgroup of MDS patients in whom immune-mediated hematopoietic failure is part of the disease process. As such, the CD40–CD40L-based activation of monocytes might be a target to counteract MDS-related BM failure.
British Journal of Haematology | 2012
Shanti Natarajan-Amé; Sophie Park; Lionel Ades; Norbert Vey; Agnès Guerci-Bresler; Jean-Yves Cahn; Gabriel Etienne; Dominique Bordessoule; Christophe Ravoet; Laurence Legros; Stéphane Cheze; Aspasia Stamatoullas; Elisabeth Berger; Aline Schmidt; Aude Charbonnier; M.P. Chaury; Thorsten Braun; Pierre Fenaux; Francois Dreyfus
Marrow cells from patients with higher‐risk myelodysplastic syndrome (MDS) exhibit constitutive nuclear factor (NF)‐κB activation. The proteasome inhibitor, bortezomib, has limited efficacy as a single agent in acute myeloid leukaemia. Its activity on leukaemic cell lines is potentiated by chemotherapy. We treated 43 higher‐risk MDS patients with bortezomib (1·5 mg/m2, days 1, 4, 8 and 11) and low dose cytarabine arabinoside (LDAC; 10 mg/m2, then 20 mg/m2 from days 1–14), every 28 d for four cycles. Median follow‐up was 29·7 months. Responses were seen in 12 of the 43 patients (28%), including complete response (CR, n = 1), marrow‐CR (n = 3), partial response (PR, n = 5) and haematological improvement (HI, n = 3). Responses were seen in 12 (36%) of the 33 previously untreated patients (11% CR, 13% PR, 2·5% HI), compared to none in the 12 previously treated patients (P < 0·01). Responders had better overall survival (median 18·2 vs. 10 months). One CR and 3 marrow‐CRs were seen in patients with complex karyotypes. Main toxicity was haematological, responsible for infection in six patients and bleeding in 3. Three patients with Grade 1–2 pre‐treatment haematotoxicity developed Grade 3–4 toxicity. Neuropathy was seen in 12% of patients. The addition of bortezomib to LDAC in higher‐risk MDS may improve results obtained with LDAC alone, especially in patients with unfavourable karyotypes.
Leukemia & Lymphoma | 2000
Françoise Tassin; Walthère Dewé; Nicole Schaaf; Christian Herens; Christophe Ravoet; Adelin Albert; Yves Beguin; Jean-Michel Paulus
Marrow dysplasia is a major characteristic of patients with myelodysplastic syndrome (MDS), along with marrow blastosis, cytopenia and cytogenetic anomalies. However, the impact of the degree of marrow dysplasia on survival has not been fully assessed. In this retrospective analysis of 111 patients selected according to the IPSS criteria of MDS diagnosis, the presence or absence of 21 dysplasia characteristics recognizable in bone marrow smears stained by the May-Griinwald-Giemsa method was correlated with patient survival. Using Cox proportional hazards regression analysis, megaloblastosis (MEGALO), neutrophil agran-ularity (AGRAN) and hypogranularity (HYPOGRAN) were highly significant predictors (p < 0.005), and Pelger-Huët anomaly (PELGHUET) a significant predictor (p = 0.05), of patient survival. The regression analysis yielded a dysplasia-based risk index (D1) where DI = 1.26 MEGALO + 0.82 AGRAN - 1.08 HYPOGRAN + 0.45 PELGHUET. The two subgroups of 60 and 47 patients with DI ≤ 0 and > 0 showed highly significant differences in median survivals (2.6 vs 1.1 yrs; p <0.0001). Multivariate analysis further showed that DI offered additional predictive power that was independent of that provided by the IPSS (p=0.002 and 0.001 respectively). Analysis of survival curves stratified for IPSS and DI showed that the additional predictive power offered by inclusion of the DI essentially concerned the IPSS low/INT-1 risk categories. Further stratification for age did not improve survival prediction. The data indicate that a set of 4 dysplasia parameters can offer some prediction for survival of MDS patients in addition to that provided by the IPSS. Further mul-ticenter studies should aim at including some form of evaluation of the degree of dysplasia in prognostic systems.
European Journal of Haematology | 2009
Walter Feremans; Geneviève Bastin; F Le Moine; Christophe Ravoet; Jean Pierre Delville; Olivier Pradier; G Wallef; Paul Capel; Micheline Lambermont
Abstract: Very high‐dose chemotherapy with autologous blood stem cell (BSC) rescue becomes more and more widely performed. In order to simplify the technique, a large volume apheresis programme combined with an uncontrolled rate cryopreservation at –80°C was developed. Twenty‐six patients suffering from multiple myeloma (n = 8), non‐Hodgkins lymphoma (n = 7), dysgerminoma (n = 4), breast cancer (n = 3), Hodgkins disease (n = 2), acute lymphoblastic leukaemia (n = 1) and acute myelocytic leukaemia (n = 1) were autografted after a classical high‐dose chemotherapy regimen. A single large volume apheresis was sufficient to obtain the threshold value of CD34+ BSC in 24/26 transplantations. The haematological recovery was favourably comparable with the previously published data obtained with controlled rate frozen BSC: median time to granulocytes > 1000/μL and to a self‐supporting platelet count > 20,000/μL, respectively, 10.5 and 12 d. The treatment‐related mortality was confined to 1/26 BSCT. These results indicate that this easy and cost‐saving policy of BSCT is efficacious and safe: sustained long‐term haematopoiesis, reduced morbidity and mortality were observed.
Acta Clinica Belgica | 2015
Yves Beguin; Dominik Selleslag; Stef Meers; Carlos Graux; Greet Bries; Dries Deeren; Inge Vrelust; Christophe Ravoet; Koen Theunissen; Verena Voelter; Hélène Potier; Fabienne Trullemans; Lucien Noens; Philippe Mineur
Abstract Objectives: We evaluated azacitidine (Vidaza®) safety and efficacy in patients with myelodysplastic syndrome (MDS), acute myeloid leukaemia (AML), and chronic myelomonocytic leukaemia (CMML), in a real-life setting. Treatment response, dose, and schedule were assessed. Methods: This non-interventional, post-marketing survey included 49/50 patients receiving azacitidine at 14 Belgian haematology centres from 2010–2012. Treatment-emergent adverse events (TEAEs), including treatment-related TEAEs, and serious TEAEs (TESAEs) were recorded throughout the study. Treatment response [complete response (CR), partial response (PR), haematological improvement (HI), stable disease (SD), treatment failure (TF)) and transfusion-independence (TI) were evaluated at completion of a 1-year observation period (1YOP) or at treatment discontinuation, and overall survival (OS), at study conclusion. Results: The median age of patients was 74·7 (range: 43·9–87·8) years; 69·4% had MDS, 26·5% had primary or secondary AML, and 4·1% had CMML. Treatment-related TEAEs, grade 3–4 TEAEs, and TESAEs were reported in 67·3%, 28·6%, and 18·4% of patients, respectively. During 1YOP, patients received a median of 7 (1–12) treatment cycles. Treatment response was assessed for 38/49 patients. Among MDS and CMML patients (n = 29), 41·4% had CR, PR, or HI, 41·4% had SD, and 17·2% had TF. Among AML patients (n = 9), 44·4% had CR or PR, 33·3% had SD, and 22·2% had TF. TI was observed in 14/32 (43·8%) patients who were transfusion-dependent at baseline. Median (95% confidence interval) OS was 490 (326–555) days; 1-year OS estimate was 0·571 (0·422–0·696). Conclusions: Our data support previous findings that azacitidine has a clinically acceptable safety profile and shows efficacy.