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Featured researches published by R. A. Feelders.


European Journal of Endocrinology | 2009

Combined treatment for acromegaly with long-acting somatostatin analogs and pegvisomant: long-term safety for up to 4.5 years (median 2.2 years) of follow-up in 86 patients

Sebastian Neggers; W. W. de Herder; J. A. M. J. L. Janssen; R. A. Feelders; A. J. van der Lely

BACKGROUNDnWe previously reported on the efficacy, safety, and quality of life (QoL) of long-acting somatostatin analogs (SSA) and (twice) weekly pegvisomant (PEG-V) in acromegaly and improvement after the addition of PEG-V to long-acting SSA.nnnOBJECTIVEnTo assess the long-term safety in a larger group of acromegalic patients over a larger period of time: 29.2 (1.2-57.4) months (mean (range)).nnnDESIGNnPegvisomant was added to SSA monotherapy in 86 subjects (37 females), to normalize serum IGF1 concentrations (n=63) or to increase the QoL. The median dosage was 60.0 (20-200) mg weekly.nnnRESULTSnAfter a mean treatment period of 29.2 months, 23 patients showed dose-independent PEG-V related transient liver enzyme elevations (TLEE). TLEE occurred only once during the continuation of combination therapy, but discontinuation and re-challenge induced a second episode of TLEE. Ten of these patients with TLEE also suffered from diabetes mellitus (DM). In our present series, DM had a 2.28 odds ratio (CI 1.16-9.22; p=0.03) higher risk for developing TLEE. During the combined therapy, a clinical significant decrease in tumor size by more than 20% was observed in 14 patients. Two of these patients were previously treated by pituitary surgery, 1 with additional radiotherapy and all other patients received primary medical treatment.nnnCONCLUSIONnLong-term combined treatment with SSA and twice weekly PEG-V up to more than 4 years seems to be safe. Patients with both acromegaly and DM have a 2.28 higher risk of developing TLEE. Clinical significant tumor shrinkage was observed in 14 patients during combined treatment.


The Journal of Clinical Endocrinology and Metabolism | 2009

Quality of Life in Acromegalic Patients during Long-Term Somatostatin Analog Treatment with and without Pegvisomant

Sebastian Neggers; M. O. van Aken; W. W. de Herder; R. A. Feelders; J. A. M. J. L. Janssen; Xavier Badia; Susan M. Webb; A. J. van der Lely

OBJECTIVEnThe objective of the study was to assess whether weekly administration of 40 mg pegvisomant (PEG-V) improves quality of life (QoL) and metabolic parameters in acromegalic patients with normal age-adjusted IGF-I concentrations during long-acting somatostatin analog (SSA) treatment.nnnDESIGNnThis was a prospective, investigator-initiated, double blind, placebo-controlled, crossover study. Twenty acromegalic subjects received either PEG-V or placebo for two consecutive treatment periods of 16 wk, separated by a washout period of 4 wk. Efficacy was assessed as change between baseline and end of each treatment period. QoL was assessed by the Acromegaly Quality of Life Questionnaire (AcroQoL) and the Patient-Assessed Acromegaly Symptom Questionnaire (PASQ).nnnRESULTSnThe AcroQoL (P = 0.008) and AcroQoL physical (P = 0.002) improved significantly after PEG-V was added. The addition of PEG-V also significantly improved the PASQ (P = 0.038) and the single PASQ questions, perspiration (P = 0.024), soft tissue swelling (P = 0.036), and overall health status (P = 0.035). No significant change in Z-score of IGF-I (P = 0.34) was observed during addition of PEG-V. Transient liver enzyme elevations were observed in five subjects (25%).nnnCONCLUSIONnImprovement in quality of life was observed without significant change in IGF-I after the addition of 40 mg pegvisomant weekly to monthly SSA therapy in acromegalic patients who had normalized IGF-I on SSA monotherapy. These data question the current recommendations in how to assess disease activity in acromegaly. Moreover, the findings question the validity of the current approach of medical treatment in which pegvisomant is used only when SSA therapy has failed to normalize IGF-I.


The Journal of Clinical Endocrinology and Metabolism | 2012

The hypercoagulable state in Cushing's disease is associated with increased levels of procoagulant factors and impaired fibrinolysis, but is not reversible after short-term biochemical remission induced by medical therapy.

R. van der Pas; C. de Bruin; F. W. G. Leebeek; M.P.M. de Maat; D. Rijken; Alberto M. Pereira; Johannes A. Romijn; Romana T. Netea-Maier; A.R.M.M. Hermus; Pierre Zelissen; F.H. de Jong; A. J. van der Lely; W. W. de Herder; S. W. J. Lamberts; L. J. Hofland; R. A. Feelders

CONTEXTnCushings disease (CD) is accompanied by an increased risk of venous thromboembolism. Surgery is the primary treatment of CD.nnnOBJECTIVEnThe aim of the study was to compare hemostatic parameters between patients with CD and controls and to evaluate the effect of medical treatment of CD on hemostasis.nnnDESIGN AND SETTINGnDuring 80 d, stepwise medical treatment was applied with the somatostatin analog pasireotide, the dopamine agonist cabergoline, and ketoconazole, which suppresses adrenocortical steroidogenesis, at four university medical centers in The Netherlands.nnnPATIENTSnSeventeen patients with de novo, residual, or recurrent CD were included.nnnMAIN OUTCOME MEASURESnWe measured urinary free cortisol and parameters of coagulation and fibrinolysis.nnnRESULTSnPatients with CD had significantly higher body mass index (P < 0.001), shortened activated partial thromboplastin time (P < 0.01), and higher levels of fibrinogen, Factor VIII, and protein S activity (P < 0.05) compared to healthy control subjects. In addition, fibrinolytic capacity was impaired in patients with CD as reflected by prolonged clot lysis time (P < 0.001) and higher levels of plasminogen activator inhibitor type 1, thrombin-activatable fibrinolysis inhibitor, and α2-antiplasmin (P < 0.01). There were no statistically significant differences in von Willebrand factor:antigen, antithrombin, and protein C activity. After 80 d, 15 of 17 patients had normalized urinary free cortisol excretion. Despite biochemical remission, only slight decreases in antithrombin (P < 0.01) and thrombin-activatable fibrinolysis inhibitor (P < 0.05) levels were observed. Other parameters of coagulation and fibrinolysis did not change significantly.nnnCONCLUSIONSnThe hypercoagulable state in patients with CD, which is explained by both increased production of procoagulant factors and impaired fibrinolysis, is not reversible upon short-term biochemical remission after successful medical therapy. This may have implications for the duration of anticoagulant prophylaxis in patients with (cured) CD.


The Journal of Clinical Endocrinology and Metabolism | 2014

Long-Term Efficacy and Safety of Pegvisomant in Combination With Long-Acting Somatostatin Analogs in Acromegaly

S. Neggers; S. E. Franck; F. W. M. de Rooij; Alof H G Dallenga; R.M.L. Poublon; R. A. Feelders; J. A. M. J. L. Janssen; Michael Buchfelder; L. J. Hofland; Jens Otto Lunde Jørgensen; A. J. van der Lely

BACKGROUNDnTreatment for acromegaly patients with long-acting somatotropin release-inhibiting factor (LA-SRIF) often does not result in complete normalization of IGF-1. Addition of pegvisomant (PEGV), a GH receptor antagonist, could improve this; however, the literature has not described long-term follow-up.nnnOBJECTIVEnTo assess long-term efficacy and safety of this combined treatment in the largest current single-center cohort of patients, from 2004-2013.nnnDESIGNnAcromegaly patients were treated for at least 6 months with a high-dose LA-SRIF. To patients with persistently elevated IGF-1 levels (>1.2 × upper limit of normal) or poor quality of life, PEGV was added as one weekly injection.nnnRESULTSnThe patients (n = 141) were treated with PEGV and LA-SRIFs for a median period of 4.9 years (range, 0.5-9.2). Efficacy, defined as the lowest measured IGF-1 level during treatment, was 97.0%. The median PEGV dose to achieve this efficacy was 80 mg weekly (interquartile range, 60-120 mg). Combination treatment-related adverse events were recorded in 26 subjects (18.4%). Pituitary tumor size increase was observed in one patient. Injection-site reactions were observed in four subjects. In 19 patients (13.5%), transiently elevated liver transaminases of more than three times the upper limit of normal were observed, of which 83% occurred within the first year of combination treatment. Eight patients died, at a mean age of 71 years; none of them were considered treatment-related.nnnCONCLUSIONSnThe combination treatment with LA-SRIFs and PEGV was effective in 97% of the patients, it appears to be a safe medical treatment and it reduces the required dose of PEGV.


Neuroendocrinology | 2010

Biochemical Predictors of Outcome of Pituitary Surgery for Cushing’s Disease

R A Alwani; W. W. de Herder; M. O. van Aken; J. H. van den Berge; E.J. Delwel; A.H.G. Dallenga; F.H. de Jong; S. W. J. Lamberts; A. J. van der Lely; R. A. Feelders

Objective: Transsphenoidal surgery (TS) is the primary therapy for Cushing’s disease (CD). The aims of this retrospective study were twofold: (i) investigate early and late results of TS for CD, and (ii) evaluate various postoperative tests in order to predict the outcome of TS. Methods: We reviewed the long-term outcome in 79 patients with CD who underwent TS (median follow-up 84 months, range 6–197). Within 2 weeks after surgery, morning serum cortisol concentrations were obtained (n = 78) and corticotropin-releasing hormone (CRH) (n = 53) and metyrapone tests (n = 72) were performed. Three groups of outcome were identified: sustained remission, early failure (persistent CD), and late relapse. Results: Immediate postoperative remission was achieved in 51 patients (65%), whereas 28 patients (35%) had persistent CD after TS. Ten patients developed recurrent CD after initial remission (20%). Morning cortisol: all relapses but one recorded serum cortisol >50 nmol/l. A cortisol threshold value of 200 nmol/l has a positive predictive value of 79% for immediate surgical failure (negative predictive failure [NPV] 97%). CRH test: CRH-stimulated peak cortisol ≧600 nmol/l predicted early failure in 78% (NPV 100%). All relapses recorded CRH-stimulated peak cortisol ≧485 nmol/l. Metyrapone test: 11-deoxycortisol ≧345 nmol/l predicted an early failure in 86% of cases (NPV 94%). Conclusion: Predictive factors of surgical failure are morning cortisol ≧200 nmol/l, 11-deoxycortisol ≧345 nmol/l after metyrapone and CRH-stimulated cortisol ≧600 nmol/l. CRH and/or metyrapone testing are not superior to morning cortisol concentration in the prediction of outcome of TS. Careful long-term follow-up remains necessary independent of the outcome of biochemical testing.


Histopathology | 2007

The prognostic value of two different histopathological scoring systems for adrenocortical carcinomas.

H P Van't Sant; N.D. Bouvy; Geert Kazemier; H. J. Bonjer; Wim C. J. Hop; R. A. Feelders; W. W. de Herder; R.R. de Krijger

Aims:u2002 To compare two different multiparameter histopathological scoring indices and determine their prognostic value in patients presenting with adrenocortical carcinoma (ACC).


The Journal of Clinical Endocrinology and Metabolism | 2012

Mifepristone Effects on Tumor Somatostatin Receptor Expression in Two Patients with Cushing's Syndrome due to Ectopic Adrenocorticotropin Secretion

C. de Bruin; L. J. Hofland; Lynnette K. Nieman; P. M. van Koetsveld; A. M. Waaijers; D M Sprij-Mooij; M. van Essen; S. W. J. Lamberts; W. W. de Herder; R. A. Feelders

CONTEXTnTwo patients presented with Cushings syndrome due to ectopic ACTH secretion. Initial localization studies included computed tomography, magnetic resonance imaging, and octreoscans ((111)In-pentreotide scintigraphy), which were negative in both patients. They were treated with the glucocorticoid receptor antagonist mifepristone, with improvement in their clinical symptoms. Follow-up octreoscans after, respectively, 6 and 12 months showed the unequivocal presence of a bronchial carcinoid in both patients.nnnOBJECTIVEnThe objective of the study was to correlate in vivo and in vitro findings in patients with ectopic ACTH-producing syndrome.nnnMETHODSnWe determined the expression of somatostatin and dopamine receptors by immunohistochemistry (patients 1 and 2), quantitative PCR, and in vitro culturing of tumor cells (patient 1 only). IN VITRO RESULTS: Both tumors were strongly positive for somatostatin receptor type 2 (sst(2)) on immunohistochemistry, whereas one of the tumors (patient 1) was also dopamine receptor subtype 2 (D(2)) positive on both immunohistochemistry and quantitative PCR. Octreotide (a sst(2) preferring analog) and cabergoline (D(2) agonist) both decreased the ACTH levels in the cultured tumor cells of patient 1.nnnCONCLUSIONnWe describe two patients with ACTH-producing bronchial carcinoids, in whom a direct down-regulatory effect of glucocorticoid levels on tumoral sst(2) receptor expression is suggested by a remarkable change in octreoscan status after successful mifepristone therapy. Further studies will have to demonstrate whether glucocorticoid lowering or antagonizing therapy may be used to improve the diagnostic accuracy of somatostatin receptor scintigraphy in patients with ectopic ACTH production of unknown primary origin.


The Journal of Clinical Endocrinology and Metabolism | 2009

Effects of Somatostatin Analogs on a Growth Hormone-Releasing Hormone Secreting Bronchial Carcinoid, in Vivo and in Vitro Studies

M. van Hoek; L. J. Hofland; Y. B. de Rijke; F. H. van Nederveen; R.R. de Krijger; P. M. van Koetsveld; Steven W. J. Lamberts; A. J. van der Lely; W. W. de Herder; R. A. Feelders

CONTEXTnA 56-yr-old woman presented with acromegaly, a pulmonary mass, and elevated levels of GHRH, GH, and IGF-I. Histological examination revealed a bronchial carcinoid with positive staining for GHRH. Somatostatin analogs (SAs) can play an important role in the treatment of neuroendocrine tumors, dependent on the somatostatin receptor subtype (sst) expression pattern. The sst pattern in bronchial carcinoids and effects of SAs have not been extensively investigated, particularly not for the recently developed universal SA SOM230 (Pasireotide) that has high affinity for sst1, 2, 3, and 5.nnnOBJECTIVEnOur objective was to investigate the in vivo response of a GHRH-producing bronchial carcinoid to octreotide (OCT), its sst-expression profile, and in vitro responses to different SAs, including SOM230.nnnMETHODSnIn vivo, 50 microg OCT was administered, and plasma GH and GHRH responses were determined. In vitro, the expression of ssts was analyzed by quantitative PCR. Furthermore, the effects of SOM230 and OCT on GHRH secretion were evaluated in primary cell cultures of the carcinoid tissue.nnnRESULTSnIn vivo, OCT administration fully suppressed GH and GHRH levels. In vitro, sst1 mRNA was most abundant, followed by sst2 and sst5. Both SOM230 and OCT inhibited GHRH production dose dependently (SOM230 100 nm vs. control, P = 0.01; OCT 110 nm vs. control, P = 0.05).nnnCONCLUSIONSnIn this case of a GHRH-producing bronchial carcinoid, we demonstrated that SOM230 was a potent inhibitor of GHRH production in vitro and was at least equally potent compared with OCT. Therefore, SOM230 may be a potential therapeutic agent to control GHRH secretion in ectopic acromegaly.


The Journal of Clinical Endocrinology and Metabolism | 2013

Preoperative Normalization of Cortisol Levels in Cushing's Disease After Medical Treatment: Consequences for Somatostatin and Dopamine Receptor Subtype Expression and In Vitro Response to Somatostatin Analogs and Dopamine Agonists.

R. van der Pas; R. A. Feelders; Federico Gatto; C. de Bruin; Alberto M. Pereira; P. M. van Koetsveld; D M Sprij-Mooij; A. M. Waaijers; Fadime Dogan; Stefan Schulz; Johan M. Kros; Steven W. J. Lamberts; L. J. Hofland

CONTEXTnCorticotroph pituitary adenomas often highly express the dopamine 2 receptor (D₂R) and somatostatin receptor subtype 5 (sst₅). The sst₂ expression is relatively low, likely resulting from downregulating effects of high cortisol levels. This may explain why the sst₂-preferring somatostatin analog octreotide, compared with the multi-receptor-targeting somatostatin analog pasireotide, is generally ineffective in Cushings disease.nnnOBJECTIVEnOur objective was to compare sst and D₂R expression levels between adenomas from patients with elevated and normalized preoperative urinary free cortisol excretion.nnnPATIENTS AND DESIGNnCorticotroph adenoma tissue was examined from patients from group 1 (n = 22; elevated preoperative urinary free cortisol) and group 2 (n = 11; mean duration of preoperative normocortisolism 10 weeks). Somatotroph adenoma tissue from 10 acromegalic patients was examined to compare receptor expression profiles.nnnMAIN OUTCOME MEASURESnWe evaluated receptor mRNA and protein expression levels and effects of octreotide, pasireotide, and cabergoline on ACTH secretion by cultured human corticotroph adenoma cells.nnnRESULTSnThe sst₂ mRNA expression in group 2 was 10-fold higher than in group 1 (P < .01), even comparable to that in somatotroph adenomas. There were no statistically significant differences in sst₅ and D₂R mRNA expression or in sst₂, sst₅, and D₂R protein expression between both groups of corticotroph adenomas. In responders, octreotide (n = 2 out of 4; -30.5% ± 10.4%) was less potent than pasireotide (n = 5 out of 6; -47.0% ± 4.2%) and cabergoline (n = 3 out of 4; -41.9% ± 3.1%) with respect to inhibition of ACTH secretion by adenomas from group 2.nnnCONCLUSIONSnAfter achieving normocortisolism induced by medical therapy, cortisol-mediated sst₂ downregulation on corticotroph adenomas appears to be a reversible process at the mRNA but not at the protein level. Octreotide remains less potent than pasireotide and cabergoline with respect to in vitro inhibition of ACTH secretion. Whether sustained normocortisolism induced by medical therapy induces re-expression of functional sst₂ protein in corticotroph adenomas and whether this increases the ACTH-lowering potency of octreotide remains to be established.


Pituitary | 2011

Conversion of daily pegvisomant to weekly pegvisomant combined with long-acting somatostatin analogs, in controlled acromegaly patients

Sebastian Neggers; Wouter W. de Herder; R. A. Feelders; A. J. van der Lely

The efficacy of combined treatment in active acromegaly with both long-acting somatostatin analogs (SRIF) and pegvisomant (PEG-V) has been well established. The aim was to describe the PEG-V dose reductions after the conversion from daily PEG-V to combination treatment. To clarify the individual beneficial and adverse effects, in two acromegaly patients, who only normalized their insulin like growth factor (IGF-I) levels with high-dose pegvisomant therapy. We present two cases of a 31 and 44xa0years old male with gigantism and acromegaly that were controlled subsequently by surgery, radiotherapy, SRIF analogs and daily PEG-V treatment. They were converted to combined treatment of monthly SSA and (twice) weekly PEG-V. High dose SSA treatment was added while the PEG-V dose was decreased during carful monitoring of the IGF-I. After switching from PEG-V monotherapy to SRIF analogs plus pegvisomant combination therapy IGF-I remained normal. However, the necessary PEG-V dose, to normalize IGF-I differed significantly between these two patients. One patient needed twice weekly 100xa0mg, the second needed 60xa0mg once weekly on top of their monthly lanreotide Autosolution injections of 120xa0mg. The weekly dose reduction was 80 and 150xa0mg. After the introducing of lanreotide, fasting glucose and glycosylated haemoglobin concentrations increased. Diabetic medication had to be introduced or increased. No changes in liver tests or in pituitary adenoma size were observed. In these two patients, PEG-V in combination with long-acting SRIF analogs was as effective as PEG-V monotherapy in normalizing IGF-I levels, although significant dose-reductions in PEG-V could be achieved. However, there seems to be a wide variation in the reduction of PEG-V dose, which can be obtained after conversion to combined treatment.

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W. W. de Herder

Erasmus University Rotterdam

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A. J. van der Lely

Erasmus University Rotterdam

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L. J. Hofland

Erasmus University Medical Center

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Sebastian Neggers

Erasmus University Rotterdam

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Leo J. Hofland

Erasmus University Rotterdam

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D M Sprij-Mooij

Erasmus University Rotterdam

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Fadime Dogan

Erasmus University Rotterdam

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J. A. M. J. L. Janssen

Erasmus University Medical Center

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P. M. van Koetsveld

Erasmus University Rotterdam

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