G. Verhoef
Katholieke Universiteit Leuven
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Featured researches published by G. Verhoef.
Journal of Clinical Oncology | 2003
J. Doorduijn; B. van der Holt; Gw van Imhoff; K. G. van der Hem; Mhh Kramer; M. H. J. Van Oers; Gj Ossenkoppele; M. R. Schaafsma; Lf Verdonck; G. Verhoef; Monique Steijaert; I. Buijt; Ca Uyl-de Groot; M. Van Agthoven; Andries H. Mulder; Pieter Sonneveld
PURPOSE To investigate whether the relative dose-intensity of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy could be improved by prophylactic administration of granulocyte colony-stimulating factor (G-CSF) in elderly patients with aggressive non-Hodgkins lymphoma (NHL). PATIENTS AND METHODS Patients aged 65 to 90 years (median, 72 years) with stage II to IV aggressive NHL were randomly assigned to receive standard CHOP every 3 weeks or CHOP plus G-CSF every 3 weeks on days 2 to 11 of each cycle. RESULTS In 389 eligible patients, the relative dose intensities (RDIs) of cyclophosphamide (median, 96.3% v 93.9%; P =.01) and doxorubicin (median, 95.4% v 93.3%; P =.04) were higher in patients treated with CHOP plus G-CSF. The complete response rates were 55% and 52% for CHOP and CHOP plus G-CSF, respectively (P =.63). The actuarial overall survival at 5 years was 22% with CHOP alone, compared with 24% with CHOP plus G-CSF (P =.76), with a median follow-up of 33 months. Patients treated with CHOP plus G-CSF had an identical incidence of infections, with World Health Organization grade 3 to 4 (34 of 1,191 cycles v 36 of 1,195 cycles). Only the cumulative days with antibiotics were fewer with CHOP plus G-CSF (median, 0 v 6 days; P =.006) than with CHOP alone. The number of hospital admissions and the number of days in hospital were not different. CONCLUSION In elderly patients, G-CSF improved the RDI of CHOP, but this did not lead to a higher complete response rate or better overall survival. G-CSF did not prevent serious infections.
Leukemia | 2004
Peter Vandenberghe; Lucienne Michaux; Iwona Wlodarska; Pierre Zachee; M. A. Boogaerts; D Vanstraelen; Mc Herregods; A. Van Hoof; D Selleslag; Florence Roufosse; M. Maerevoet; G. Verhoef; Jan Cools; D G Gilliland; Anne Hagemeijer; Peter Marynen
Detection of the FIP1L1-PDGFRA fusion gene or the corresponding cryptic 4q12 deletion supports the diagnosis of chronic eosinophilic leukemia (CEL) in patients with chronic hypereosinophilia. We retrospectively characterized 17 patients fulfilling WHO criteria for idiopathic hypereosinophilic syndrome (IHES) or CEL, using nested RT-PCR and interphase fluorescence in situ hybridization (FISH). Eight had FIP1L1-PDGFRA (+) CEL, three had FIP1L1-PDGFRA (−) CEL and six had IHES. FIP1L1-PDGFRA (+) CEL responded poorly to steroids, hydroxyurea or interferon-α, and had a high probability of eosinophilic endomyocarditis (n=4) and disease-related death (n=4). In FIP1L1-PDGFRA (+) CEL, palpable splenomegaly was present in 5/8 cases, serum vitamin B12 was always markedly increased, and marrow biopsies revealed a distinctively myeloproliferative aspect. Imatinib induced rapid complete hematological responses in 4/4 treated FIP1L1-PDGFRA (+) cases, including one female, and complete molecular remission in 2/3 evaluable cases. In the female patient, 1 log reduction of FIP1L1-PDGFRA copy number was reached as by real-time quantitative PCR (RQ-PCR). Thus, correlating IHES/CEL genotype with phenotype, FIP1L1-PDGFRA (+) CEL emerges as a homogeneous clinicobiological entity, where imatinib can induce molecular remission. While RT-PCR and interphase FISH are equally valid diagnostic tools, the role of marrow biopsy in diagnosis and of RQ-PCR in disease and therapy monitoring needs further evaluation.
The American Journal of Surgical Pathology | 1992
Jan Delabie; Elisabeth Vandenberghe; C. Kennes; G. Verhoef; M. P. Foschini; M. Stul; J.J. Cassiman; C. De Wolf-Peeters
This study reports six non-Hodgkins lymphoma cases that we called histiocyte-rich B-cell lymphoma (BCL) because of the prominent reactive histiocytic infiltrate obscuring the malignant B-cell population. The involved lymph nodes are characterized by a mixed nodular and diffuse infiltrate and occasionally feature prominent sinuses. The infiltrate is composed of reactive lymphocytes and numerous histiocytes obscuring a tumor population composed of variably sized scattered cells with irregular or multilobar vesicular nuclei. Immunostaining of paraffin sections for the B-cell marker recognized by L26 helps in the identification of these neoplastic cells. The clonal nature and further evidence of the B-cell lineage of this condition is shown by immunoglobulin gene rearrangements detected in three cases. The six cases of histiocyte-rich BCL are remarkably similar clinically: all presented with stage IVB disease with splenomegaly and follow an aggressive clinical course. Except for these features, our series show striking similarities to paragranuloma lymphocyte-predominant Hodgkins disease, including male preponderance (all patients are male), age distribution (mean age, 41 years), propensity to progress to a diffuse, large B-cell lymphoma (two cases), as well as morphology of the neoplastic B-cell population and expression of Hodgkins cell markers (Leu-M1 positivity after neuraminidase digestion in three cases, Leu-M1 positivity without neuraminidase digestion in one case, and additional epithelial membrane antigen [EMA] positivity in two cases). Both morphologically and clinically, the present series can be differentiated from other types of infiltrate-rich BCL, such as T-cell-rich BCL. Although additional cases will have to be recognized, histiocyte-rich B-cell lymphoma most likely represents a distinct clinicopathological entity. We speculate that it develops from a subset of B cells that also gives rise to the lymphocytic-histocytic (L/H) cell, the Hodgkins cell variant of lymphocyte-predominant Hodgkins disease, paragranuloma subtype.
Journal of Clinical Oncology | 1997
Bob Lowenberg; Marc Boogaerts; Smgj Daenen; G. Verhoef; Anton Hagenbeek; Edo Vellenga; G.J. Ossenkoppele; P. C. Huijgens; Lf Verdonck; J van der Lelie; J. J. Wielenga; H Schouten; Jurg Gmür; A. Gratwohl; Urs Hess; Martin F. Fey; W.L.J. van Putten
PURPOSE The hematopoietic growth factors (HGFs) introduced into induction chemotherapy (CT) of acute myeloid leukemia (AML) might be of benefit to treatment outcome by at least two mechanisms. HGFs given on days simultaneously with CT might sensitize the leukemic cells and enhance their susceptibility to CT. HGFs applied after CT might hasten hematopoietic recovery and reduce morbidity or mortality. MATERIALS AND METHODS We set out to evaluate the use of granulocyte-macrophage colony-stimulating factor (GM-CSF; 5 microg/kg) in a prospective randomized study of factorial design (yes or no GM-CSF during CT, and yes or no GM-CSF after CT) in patients aged 15 to 60 years (mean, 42) with newly diagnosed AML. GM-CSF was applied as follows: during CT only (+/-, n = 64 assessable patients), GM-CSF during and following CT (+/+, n = 66), no GM-CSF (-/-, n = 63), or GM-CSF after CT only (-/+, n = 60). RESULTS The complete response (CR) rate was 77%. At a median follow-up time of 42 months, probabilities of overall survival (OS) and disease-free survival (DFS) at 3 years were 38% and 37% in all patients. CR rates, OS, and DFS did not differ between the treatment groups (intention-to-treat analysis). Neutrophil recovery (1.0 x 10(9)/L) and monocyte recovery were significantly faster in patients who received GM-CSF after CT (26 days v 30 days; neutrophils, P < .001; monocytes, P < .005). Platelet regeneration, transfusion requirements, use of antibiotics, frequency of infections, and duration of hospitalization did not vary as a function of any of the therapeutic GM-CSF modalities. More frequent side effects (eg, fever and fluid retention) were noted in GM-CSF-treated patients predominantly related to the use of GM-CSF during CT. CONCLUSION Priming of AML cells to the cytotoxic effects of CT by the use of GM-CSF during CT or accelerating myeloid recovery by the use of GM-CSF after CT does not significantly improve treatment outcome of young and middle-aged adults with newly diagnosed AML.
Leukemia | 1997
Judith Dierlamm; C Rosenberg; M. Stul; Stefania Pittaluga; I. Wlodarska; L Michaux; M.R.M. Dehaen; G. Verhoef; José Thomas; W de Kelver; T Bakker-Schut; J.J. Cassiman; Ak Raap; C. De Wolf-Peeters; H. Van den Berghe; A. Hagemeijer
Marginal zone B cell lymphoma (MZBCL) represents a distinct subtype of B cell non-Hodgkin’s lymphoma, which has been recently recognized and defined as a disease entity. We investigated 25 cases (18 at primary diagnosis and seven during the course of disease) of MZBCL by comparative genomic hybridization (CGH) and compared these results with cytogenetic, fluorescence in situ hybridization (FISH), and Southern blot data. Twenty of the 25 cases (80%) showed gains (total 49) or losses (total 15) of genetic material. In extranodal, nodal, and splenic MZBCL, material of chromosomes 3 (52% of cases), 18 (32%), X (24%), and 1q (16%) was most frequently gained, whereas losses predominantly involved chromosomes 17 (16%) and 9 (12%). High-level amplifications involving the regions 18q21-23 and 18q21-22, respectively, were detected in two cases. Gains of chromosomes 1q and 8q and losses of chromosome 17 or 17p occurred more frequently in relapsed or progressive lymphomas. For all of the frequently affected chromosomes, CGH allowed narrowing of the relevant subregions including 3q21-23, 3q25-29 and 18q21-23. By Southern blot analysis, the BCL2, BCL6, and CMYC proto-oncogenes were found to be a part of the over-represented regions in two cases, one case, and two cases, respectively, with gains involving 18q, 3q or 8q. In 13 cases, CGH revealed chromosomal imbalances which were not detected by cytogenetic analysis but could be confirmed by FISH or Southern blot analysis in all cases investigated. On the other hand, CGH failed to detect trisomy 3, trisomy 18, and deletion 7q in three cases with a low proportion of tumor cells bearing these abnormalities, as shown by interphase FISH. The characteristic pattern of chromosomal gains and losses detected in this study confirms the distinct nature of MZBCL and may point to chromosomal regions involved in the pathogenesis of these neoplasms.
British Journal of Haematology | 1999
Christine M. Segeren; Pieter Sonneveld; B. van der Holt; Joke W. Baars; Douwe H. Biesma; J. J. Cornellissen; Alexandra J. Croockewit; A. W. Dekker; W. E. Fibbe; B Lowenberg; M. van Marwijk Kooy; M. H. J. Van Oers; D. J. Richel; H Schouten; Edo Vellenga; G. Verhoef; P. Wijermans; S. Wittebol; Hm Lokhorst
We examined the feasibility of achieving a rapid response in patients with previously untreated multiple myeloma by administering vincristine 0.4 mg and doxorubicin 9 mg/m2 as a rapid intravenous infusion for 4 d together with intermittent high‐dose dexamethasone 40 mg (VAD) for remission induction treatment in patients who were scheduled to receive high‐dose therapy. 139 patients (86 male, 53 female; median age 53 years, range 32–65 years; Durie & Salmon stage IIA: 42, IIB: one, IIIA: 89, IIIB: seven) were included in a prospective multicentre study in which VAD was administered as remission induction treatment and was followed by intensified treatment. The response was evaluated according to the criteria of the Eastern Cooperative Oncology Group (ECOG). The results of treatment were evaluable in 134 patients. Five patients died before evaluation. 86 patients (62%) achieved a partial response (PR) and seven patients (5%) achieved a complete response (CR), which equates to a response rate of 67%. The main side‐effect was mild neurotoxicity, which was observed in 18% of the patients. Fever or infections were reported in 27% of the patients. VAD administered as an outpatient regimen, based on rapid intravenous infusion, is an effective induction regimen for untreated myeloma with a 67% response rate and acceptable toxicity.
Annals of Hematology | 2000
Johan Maertens; Katrien Lagrou; H Deweerdt; Ignace Surmont; G. Verhoef; Jan Verhaegen; Marc Boogaerts
Abstract We describe a case of proven disseminated infection by Scedosporium prolificans in a profoundly neutropenic patient. The patient presented with a fever unresponsive to broad-spectrum antibiotics, endophthalmitis, respiratory failure and a renal abscess. The organism was isolated from bronchoalveolar lavage fluid and from pus obtained through a sterile puncture. Review of the English-language literature identified 28 additional cases; these occurred exclusively in severely neutropenic patients (predominantly leukaemia) and in transplant recipients. Apart from two or possibly three cases, dissemination was uniformly fatal due to persistent neutropenia and inherited resistance of these pathogens to currently available antifungal drugs. At present, the optimal treatment of S. prolificans infections is unknown, but reversal of the underlying deficient immune status appears of great importance.
Leukemia | 1998
Tomasz Szczepański; A W Langerak; Ingrid L. M. Wolvers-Tettero; G.J. Ossenkoppele; G. Verhoef; Michel Stul; E. J. Petersen; M. A. C. De Bruijn; M. B. Van't Veer; J J M van Dongen
In order to gain insight into immunoglobulin (Ig) and T cell receptor (TCR) gene rearrangements in adult acute lymphoblastic leukemia (ALL), we studied 48 adult patients: 26 with precursor-B-ALL and 22 with T-ALL. Southern blotting (SB) with multiple DNA probes for the IGH, IGK, TCRB, TCRG, TCRD and TAL1 loci revealed rearrangement patterns largely comparable to pediatric ALL, but several differences were found for precursor-B-ALL patients. Firstly, adult patients showed a lower level of oligoclonality in the IGH gene locus (five out of 26 patients; 19%) despite a comparable incidence of IGH gene rearrangements (24 out of 26 patients; 92%). Secondly, all detected IGK gene deletions (n = 12) concerned rearrangements of the kappa deleting element (Kde) to Vκ gene segments, which represent two-thirds of the Kde rearrangements in pediatric precursor-B-ALL and only half of the Kde rearrangements in mature B cell leukemias. Thirdly, a striking predominance of immature Dδ2-Dδ3 cross-lineage recombinations was observed (seven out of 16 TCRD rearrangements; 44%), whereas more mature Vδ2-Dδ3 gene rearrangements occurred less frequently (six out of 16 TCRD rearrangements; 38% vs >70% in pediatric precursor-B-ALL). Together these data suggest that the Ig/TCR genotype of precursor-B-ALL is more immature and more stable in adults than in children. We also evaluated whether heteroduplex analysis of polymerase chain reaction (PCR) products of rearranged Ig and TCR genes can be used for identification of molecular targets for minimal residual disease (MRD) detection. Using five of the major gene targets (IGH, IGK, TCRG, TCRD and TAL1 deletion), we compared the SB data and heteroduplex PCR results. High concordance between the two methods ranging from 96 to 100% was found for IGK, TCRG and TAL1 genes. The concordance was lower for IGH (70%) and TCRD genes (90%), which may be explained by incomplete or ‘atypical’ rearrangements or by translocations detectable only by SB. Finally, the heteroduplex PCR data indicate, that MRD monitoring is possible in almost 90% of adult precursor-B-ALL and >95% of adult T-ALL patients.
Bone Marrow Transplantation | 1999
Edo Vellenga; Wlj van Putten; M. A. Boogaerts; Simon Daenen; G. Verhoef; Anton Hagenbeek; Andries R. Jonkhoff; P. C. Huijgens; Lf Verdonck; J van der Lelie; Jurg Gmür; P. Wijermans; A. Gratwohl; Urs Hess; Martin F. Fey; B Lowenberg
The clinical use of autologous marrow transplantation in acute myeloid leukemia (AML) has been hampered by the inability to collect adequate numbers of cells after remission induction chemotherapy and the notably delayed hematopoietic regeneration following autograft reinfusion. Here we present a study in which the feasibility of mobilizing stem cells was investigated in newly diagnosed AML. Among 96 AML patients, 76 patients (79%) entered complete remission. Mobilization was undertaken with low dose and high dose schedules of G-CSF in 63 patients, and 54 patients (87%) were leukapheresed. A median of 2.0 × 106 CD34+cells/kg (range 0.1–72.0) was obtained in a median of three leukaphereses following a low dose G-CSF schedule (150 μg/m2) during an average of 20 days. Higher dose regimens of G-CSF (450 μg/m2 and 600 μg/m2) given during an average of 11 days resulted in 28 patients in a yield of 3.6 × 106 CD34+ cells/kg (range 0–60.3) also obtained following three leukaphereses. The low dose and high dose schedules of G-CSF permitted the collection of 2 × 106 CD34-positive cells in 46% and 79% of cases respectively (P = 0.01). Twenty-eight patients were transplanted with a peripheral blood stem cell (PBSC) graft and hemopoietic repopulation was compared with the results of a previous study with autologous bone marrow. Recovery of granulocytes (>0.5 × 109/l, 17 vs 37 days) and platelets (>20 × 109/l; 26 vs 96 days) was significantly faster after peripheral stem cell transplantation compared to autologous bone marrow transplantation. These results demonstrate the feasibility of PBSCT in the majority of cases with AML and the potential advantage of this approach with respect to hemopoietic recovery.
Journal of Clinical Oncology | 2002
R. Achten; G. Verhoef; Lucien Vanuytsel; C. De Wolf-Peeters
PURPOSE Although it has proven difficult to delineate diagnostically reproducible and clinically relevant subgroups, the heterogeneity of diffuse large B-cell lymphomas (DLBCL) is widely acknowledged. In 1992, we reported on six cases that suggested that large B-cell lymphoma rich in stromal histiocytes and T cells may be identified as a distinct clinicopathologic entity within DLBCL. PATIENTS AND METHODS An integrated clinicopathologic study of 40 cases of this DLBCL subtype is presented. RESULTS Distinguishing a DLBCL rich in histiocytes and reactive T cells, designated T-cell/histiocyte--rich large B-cell lymphoma (THR-BCL), may be justified from a clinical point of view. The disease typically affects middle-aged male patients who usually present with advanced-stage disease that is not adequately managed with current therapeutic strategies. Whereas proliferation fraction and p53 overexpression, in addition to the clinical variables incorporated in the International Prognostic Index (IPI), significantly correlate with response to treatment and survival in a univariate analysis, only the IPI score identifies relevant prognostic THR-BCL subpopulations in a multivariate model. The morphologic and immunophenotypic profile of the neoplastic B cells in THR-BCL suggests that they may originate from a germinal center ancestor. CONCLUSION THR-BCL constitutes a distinct clinicopathologic entity that is characterized by an aggressive behavior. Experimental therapeutic strategies may be indicated to obtain a more favorable response to treatment in this disease.