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Dive into the research topics where W. W. de Herder is active.

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Featured researches published by W. W. de Herder.


Virchows Archiv | 2006

TNM staging of foregut (neuro)endocrine tumors: a consensus proposal including a grading system

Guido Rindi; G. Klöppel; H. Alhman; Martyn Caplin; Anne Couvelard; W. W. de Herder; B. Erikssson; Alberto Falchetti; Massimo Falconi; Paul Komminoth; Meike Körner; José Manuel Lopes; A-M. McNicol; Ola Nilsson; Aurel Perren; Aldo Scarpa; J.Y. Scoazec; B. Wiedenmann

The need for standards in the management of patients with endocrine tumors of the digestive system prompted the European Neuroendocrine Tumor Society (ENETS) to organize a first Consensus Conference, which was held in Frascati (Rome) and was based on the recently published ENETS guidelines on the diagnosis and treatment of digestive neuroendocrine tumors (NET). Here, we report the tumor–node–metastasis proposal for foregut NETs of the stomach, duodenum, and pancreas that was designed, discussed, and consensually approved at this conference. In addition, we report the proposal for a working formulation for the grading of digestive NETs based on mitotic count and Ki-67 index. This proposal, which needs to be validated, is meant to help clinicians in the stratification, treatment, and follow-up of patients.


Neuroendocrinology | 2004

Guidelines for the diagnosis and treatment of neuroendocrine gastrointestinal tumours. A consensus statement on behalf of the European Neuroendocrine Tumour Society (ENETS).

Ursula Plöckinger; Guido Rindi; Rudolf Arnold; Barbro Eriksson; E.P. Krenning; W. W. de Herder; A. Goede; Martyn Caplin; Kjell Öberg; Jean Claude Reubi; Ola Nilsson; G. Delle Fave; P. Ruszniewski; Håkan Ahlman; Bertram Wiedenmann

Guidelines for the diagnosis and treatment of neuroendocrine gastrointestinal tumours. A consensus statement on behalf of the European Neuroendocrine Tumour Society (ENETS).


Journal of the National Cancer Institute | 2012

TNM Staging of Neoplasms of the Endocrine Pancreas: Results From a Large International Cohort Study

Guido Rindi; Massimo Falconi; Catherine Klersy; Luca Albarello; Letizia Boninsegna; Markus W. Büchler; Carlo Capella; Martyn Caplin; Anne Couvelard; Claudio Doglioni; G. Delle Fave; L Fischer; Giuseppe Fusai; W. W. de Herder; Henning Jann; Paul Komminoth; R.R. de Krijger; S La Rosa; Tu Vinh Luong; U Pape; Aurel Perren; Philippe Ruszniewski; Alessandra Scarpa; Anja Schmitt; Enrico Solcia; B Wiedenmann

BACKGROUND Both the European Neuroendocrine Tumor Society (ENETS) and the International Union for Cancer Control/American Joint Cancer Committee/World Health Organization (UICC/AJCC/WHO) have proposed TNM staging systems for pancreatic neuroendocrine neoplasms. This study aims to identify the most accurate and useful TNM system for pancreatic neuroendocrine neoplasms. METHODS The study included 1072 patients who had undergone previous surgery for their cancer and for which at least 2 years of follow-up from 1990 to 2007 was available. Data on 28 variables were collected, and the performance of the two TNM staging systems was compared by Cox regression analysis and multivariable analyses. All statistical tests were two-sided. RESULTS Differences in distribution of sex and age were observed for the ENETS TNM staging system. At Cox regression analysis, only the ENETS TNM staging system perfectly allocated patients into four statistically significantly different and equally populated risk groups (with stage I as the reference; stage II hazard ratio [HR] of death = 16.23, 95% confidence interval [CI] = 2.14 to 123, P = .007; stage III HR of death = 51.81, 95% CI = 7.11 to 377, P < .001; and stage IV HR of death = 160, 95% CI = 22.30 to 1143, P < .001). However, the UICC/AJCC/WHO 2010 TNM staging system compressed the disease into three differently populated classes, with most patients in stage I, and with the patients being equally distributed into stages II-III (statistically similar) and IV (with stage I as the reference; stage II HR of death = 9.57, 95% CI = 4.62 to 19.88, P < .001; stage III HR of death = 9.32, 95% CI = 3.69 to 23.53, P = .94; and stage IV HR of death = 30.84, 95% CI = 15.62 to 60.87, P < .001). Multivariable modeling indicated curative surgery, TNM staging, and grading were effective predictors of death, and grading was the second most effective independent predictor of survival in the absence of staging information. Though both TNM staging systems were independent predictors of survival, the UICC/AJCC/WHO 2010 TNM stages showed very large 95% confidence intervals for each stage, indicating an inaccurate predictive ability. CONCLUSION Our data suggest the ENETS TNM staging system is superior to the UICC/AJCC/WHO 2010 TNM staging system and supports its use in clinical practice.


The Lancet | 2005

Combined therapy with somatostatin analogues and weekly pegvisomant in active acromegaly

J Feenstra; W. W. de Herder; Smth ten Have; Aw van den Beld; Richard A. Feelders; Jamjl Janssen; A. J. van der Lely

Pegvisomant monotherapy once daily returns concentrations of insulin-like growth factor I (IGF-I) to normal in most patients with acromegaly, but is very costly. In a 42-week dose-finding study, we assessed the efficacy of the combination of long-acting somatostatin analogues once monthly and pegvisomant once weekly in 26 patients with active acromegaly. Dose of pegvisomant was increased until IGF-I concentration became normal or until a weekly dose of 80 mg was reached. IGF-I reached normal concentrations in 18 of 19 (95%) patients who completed 42 weeks of treatment, with a median weekly dose of 60 mg pegvisomant (range 40-80). No signs of pituitary tumour growth were noted, but mild increases in liver enzymes were observed in ten patients (38%). This combined treatment is effective, might increase compliance, and could greatly reduce the costs of medical treatment for acromegaly in some patients.


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

BACKGROUND We 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. OBJECTIVE To 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)). DESIGN Pegvisomant 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. RESULTS After 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. CONCLUSION Long-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 | 2011

Incidence of Venous Thromboembolism in Patients with Cushing's Syndrome: A Multicenter Cohort Study

D. J. F. Stuijver; B. van Zaane; Richard A. Feelders; J. Debeij; Suzanne C. Cannegieter; A.R.M.M. Hermus; van den Gerrit Berg; Alberto M. Pereira; W. W. de Herder; M. A. E. M. Wagenmakers; Michael Kerstens; Pierre Zelissen; E. Fliers; Nicolaas C. Schaper; Madeleine L. Drent; Olaf M. Dekkers; Victor E. A. Gerdes

CONTEXT Venous thrombosis has frequently been reported in patients with endogenous Cushings syndrome (CS). OBJECTIVE The aim of this study was to evaluate the incidence of venous thromboembolism (VTE) in patients with CS prior to treatment and after surgery. DESIGN AND SETTING We conducted a multicenter cohort study at all university medical centers in The Netherlands. PATIENTS Consecutive patients diagnosed with endogenous CS of benign origin between January 1990 and June 2010 were eligible for inclusion. Patients surgically treated for nonfunctioning pituitary adenoma served as controls for the incidence of postoperative VTE in ACTH-dependent CS. MAIN OUTCOME MEASURES We documented all objectively confirmed VTE during 3 yr prior to, and 3 yr after treatment onset. The incidences of VTE were expressed as incidence rates. RESULTS A total of 473 patients (mean age 42 yr, 363 women) were included (360 ACTH-dependent pituitary CS). The total number of person-years was 2526. Thirty-seven patients experienced VTE during the study period, resulting in an incidence rate of 14.6 [95% confidence interval (CI) 10.3-20.1] per 1000 person-years. The incidence rate for first-ever VTE prior to treatment was 12.9 (95% CI 7.5-12.6) per 1000 person-years (17 events). The risk of postoperative VTE, defined as risk within 3 months after surgery, was 0% for ACTH-independent and 3.4% (95% CI 2.0-5.9) for ACTH-dependent CS (12 events in 350 patients); most events occurred between 1 wk and 2 months after surgery. Compared with the controls, the risk of postoperative VTE in patients undergoing transsphenoidal surgery was significantly greater (P = 0.01). CONCLUSIONS Patients with CS are at high risk of VTE, especially during active disease and after pituitary surgery. Guidelines on thromboprophylaxis are urgently needed.


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

OBJECTIVE The 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. DESIGN This 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). RESULTS The 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%). CONCLUSION Improvement 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 | 2010

Risk Factors for Hemodynamic Instability during Surgery for Pheochromocytoma

H. Bruynzeel; Richard A. Feelders; T. H. N. Groenland; A. H. Van Den Meiracker; C.H.J. van Eijck; Johan F. Lange; W. W. de Herder; Geert Kazemier

BACKGROUND Surgery on pheochromocytoma carries a risk for hemodynamic (HD) instability. The aim of this study was to identify preoperative risk factors for intraoperative HD instability. In addition, efficacy of pretreatment with the alpha-adrenergic receptor (alpha) antagonists phenoxybenzamine (PXB) and doxazosin (DOX) was compared with respect to reduction of intraoperative HD instability. METHODS Seventy-three patients operated in Erasmus Medical Center between 1995 and 2007 were included. Parameters studied were catecholamine type and concentration, tumor diameter, mean arterial pressure (MAP) before and after (MAP(alpha)) pretreatment with alpha-antagonist, postural fall in blood pressure (BP) after pretreatment, type of alpha-blockade, type of operation, and presence of a familial polytumor syndrome. HD instability was assessed by measuring the number and time period MAP was below 60 mm Hg and systolic BP (SBP) was above 160 mm Hg. RESULTS A correlation was found between the intraoperative time periods of SBP above 160 mm Hg and plasma norepinephrine levels (r = 0.23; P < 0.05), tumor diameter (r = 0.36; P < 0.01), and postural BP fall (r = 0.30; P < 0.05). MAP at presentation and after alpha-blockade above 100 mm Hg (BP, 130/85 mm Hg) was related to more and longer episodes with a SBP above 160 mm Hg (P < 0.01). Type of operation or alpha-blockade and presence of a familial polytumor syndrome were not related to intraoperative HD instability. Postoperative MAP was lower in the DOX group than in the PXB group (P < 0.05). CONCLUSION Risk factors for HD instability during surgery for pheochromocytoma include a high plasma NE concentration, larger tumor size, more profound postural BP fall after alpha-blockade, and a MAP above 100 mm Hg (130/85 mm Hg). Efficacy for preventing HD instability was identical for PXB and DOX.


Endocrine-related Cancer | 2014

Incidence of gastroenteropancreatic neuroendocrine tumours: a systematic review of the literature

Merav Fraenkel; Michelle K. Kim; Antongiulio Faggiano; W. W. de Herder; Gerlof D. Valk

Based on the current medical literature, the worldwide incidence of neuroendocrine tumours (NETs) seems to have increased; however, a systematic literature overview is lacking. This study aimed to collect all available data on the incidence of gastroenteropancreatic (GEP)-NETs and characteristics of population to establish their epidemiology. A sensitive MEDLINE search was carried out. The papers were selected via a cascade process that restricted the initial pool of 7991 articles to 33, using predefined inclusion and exclusion criteria. Original articles evaluating the incidence of sporadic GEP-NETs in regional, institutional and national registries were considered. The majority of data originated from the US National Cancer Institute Surveillance, Epidemiology and End Results database and from national cancer registries in Western Europe. Generally, because of the retrospective nature of existing databases the outcomes of studies might be biased, which hinders the drawing of firm conclusions. The age-adjusted incidence of GEP-NETs has increased steadily over the past four decades (1973-2007), increasing 3.65-fold in the USA and 3.8- to 4.8-fold in the UK. Incidence has changed variably from one anatomical site to another. The greatest increase in incidence occurred for gastric and rectal NETs, while the smallest increase occurred for small intestine NETs. There were gender and racial differences, which differed site by site and, in some cases, changed over time. The incidence rates (IRs) of GEP-NETs have increased significantly in the last 40 years. Data are only available from North America, Western Europe and Japan. A site-by-site analysis revealed that the IRs of some NETs increased more than those of others.


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

CONTEXT Cushings disease (CD) is accompanied by an increased risk of venous thromboembolism. Surgery is the primary treatment of CD. OBJECTIVE The 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. DESIGN AND SETTING During 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. PATIENTS Seventeen patients with de novo, residual, or recurrent CD were included. MAIN OUTCOME MEASURES We measured urinary free cortisol and parameters of coagulation and fibrinolysis. RESULTS Patients 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. CONCLUSIONS The 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.

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S. W. J. Lamberts

Erasmus University Rotterdam

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A. J. van der Lely

Erasmus University Rotterdam

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D. J. Kwekkeboom

Erasmus University Rotterdam

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L. J. Hofland

Erasmus University Medical Center

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Richard A. Feelders

Erasmus University Rotterdam

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R. A. Feelders

Erasmus University Medical Center

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E.P. Krenning

Erasmus University Medical Center

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R.R. de Krijger

Erasmus University Rotterdam

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C.H.J. van Eijck

Erasmus University Rotterdam

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Leo J. Hofland

Erasmus University Rotterdam

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