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Featured researches published by Ben Van Calster.


Neuropsychopharmacology | 2008

Antenatal maternal anxiety is related to HPA-axis dysregulation and self-reported depressive symptoms in adolescence: a prospective study on the fetal origins of depressed mood.

Bea Van den Bergh; Ben Van Calster; Tim Smits; Sabine Van Huffel; Lieven Lagae

Depressive symptomatology can proceed from altered hypothalamic-pituitary-adrenocortex (HPA)-axis function. Some authors stress the role that early life stress (ELS) may play in the pathophysiology of depressive symptoms. However, the involvement of the HPA-axis in linking prenatal ELS with depressive symptoms has not been tested in a prospective-longitudinal study extending until after puberty in humans. Therefore, we examined whether antenatal maternal anxiety is associated with disturbances in HPA-axis regulation and whether the HPA-axis dysregulation mediates the association between antenatal maternal anxiety and depressive symptoms in post-pubertal adolescents. As part of a prospective-longitudinal study, we investigated maternal anxiety at 12–22, 23–32, and 32–40 weeks of pregnancy (wp) with the State Trait Anxiety Inventory (STAI). In the 14–15-year-old offspring (n=58) HPA-axis function was measured through establishing a saliva cortisol day-time profile. Depressive symptoms were measured with the Childrens Depression symptoms Inventory (CDI). Results of regression analyses showed that antenatal exposure to maternal anxiety at 12–22 wp was in both sexes associated with a high, flattened cortisol day-time profile (P=0.0463) which, in female adolescents only, was associated with depressive symptoms (P=0.0077). All effects remained after controlling for maternal smoking, birth weight, obstetrical optimality, maternal postnatal anxiety and puberty phase. Our prospective study demonstrates, for the first time, the involvement of the HPA-axis in the link between antenatal maternal anxiety/prenatal ELS and depressive symptoms for post-pubertal female adolescents.


Journal of Clinical Oncology | 2005

Logistic Regression Model to Distinguish Between the Benign and Malignant Adnexal Mass Before Surgery: A Multicenter Study by the International Ovarian Tumor Analysis Group

Dirk Timmerman; Antonia Carla Testa; Tom Bourne; E. Ferrazzi; Lieveke Ameye; Maya L Konstantinovic; Ben Van Calster; William P. Collins; Ignace Vergote; Sabine Van Huffel; Lil Valentin

PURPOSE To collect data for the development of a more universally useful logistic regression model to distinguish between a malignant and benign adnexal tumor before surgery. PATIENTS AND METHODS Patients had at least one persistent mass. More than 50 clinical and sonographic end points were defined and recorded for analysis. The outcome measure was the histologic classification of excised tissues as malignant or benign. RESULTS Data from 1,066 patients recruited from nine European centers were included in the analysis; 800 patients (75%) had benign tumors and 266 (25%) had malignant tumors. The most useful independent prognostic variables for the logistic regression model were as follows: (1) personal history of ovarian cancer, (2) hormonal therapy, (3) age, (4) maximum diameter of lesion, (5) pain, (6) ascites, (7) blood flow within a solid papillary projection, (8) presence of an entirely solid tumor, (9) maximal diameter of solid component, (10) irregular internal cyst walls, (11) acoustic shadows, and (12) a color score of intratumoral blood flow. The model containing all 12 variables (M1) gave an area under the receiver operating characteristic curve of 0.95 for the development data set (n = 754 patients). The corresponding value for the test data set (n = 312 patients) was 0.94; and a probability cutoff value of .10 gave a sensitivity of 93% and a specificity of 76%. CONCLUSION Because the model was constructed from multicenter data, it is more likely to be generally applicable. The effectiveness of the model will be tested prospectively at different centers.


Lancet Oncology | 2012

Long-term cognitive and cardiac outcomes after prenatal exposure to chemotherapy in children aged 18 months or older: an observational study

Frédéric Amant; Kristel Van Calsteren; Michael Halaska; Mina Mhallem Gziri; Wei Hui; Lieven Lagae; M.A.A.P. Willemsen; Livia Kapusta; Ben Van Calster; Heidi Wouters; Liesbeth Heyns; Sileny Han; Viktor Tomek; Luc Mertens; P.B. Ottevanger

BACKGROUND Chemotherapy for the treatment of maternal cancers during pregnancy has become more acceptable in the past decade; however, the effect of prenatal exposure to chemotherapy on cardiac and neurodevelopmental outcomes of the offspring is still uncertain. We aimed to record the general health, cardiac function, and neurodevelopmental outcomes of children who were prenatally exposed to chemotherapy. METHODS We did an interim analysis of a multicentre observational cohort study assessing children who were prenatally exposed to maternal cancer staging and treatment, including chemotherapy. We assessed children at birth, at age 18 months, and at age 5-6, 8-9, 11-12, 14-15, or 18 years. We did clinical neurological examinations, tests of the general level of cognitive functioning (Bayley or intelligence quotient [IQ] test), electrocardiography and echocardiography, and administered a questionnaire on general health and development. From age 5 years, we also did audiometry, the Auditory Verbal Learning Test, and subtasks of the Childrens Memory Scale, and the Test of Everyday Attention for Children, and we also completed the Child Behavior Checklist. This study is registered with ClinicalTrials.gov, number NCT00330447. FINDINGS 236 cycles of chemotherapy were administered in 68 pregnancies. We assessed 70 children, born at a median gestational age of 35·7 weeks (range 28·3-41·0; IQR 3·3; 47 women at <37 weeks), with a median follow-up period of 22·3 months (range 16·8-211·6; IQR 54·9). Although neurocognitive outcomes were within normal ranges, cognitive development scores were lower for children who were born preterm than for those born at full term. When controlling for age, sex, and country, the score for IQ increased by an average 11·6 points (95% CI 6·0-17·1) for each additional month of gestation (p<0·0001). Our measurements of the childrens behaviour, general health, hearing, and growth corresponded with those of the general population. Cardiac dimensions and functions were within normal ranges. We identified a severe neurodevelopmental delay in both members of one twin pregnancy. INTERPRETATION Fetal exposure to chemotherapy was not associated with increased CNS, cardiac or auditory morbidity, or with impairments to general health and growth compared with the general population. However, subtle changes in cardiac and neurocognitive measurements emphasise the need for longer follow-up. Prematurity was common and was associated with impaired cognitive development. Therefore, iatrogenic preterm delivery should be avoided when possible. FUNDING Research Foundation-Flanders; Research Fund-K U Leuven; Agency for Innovation by Science and Technology; Stichting tegen Kanker; Clinical Research Fund-University Hospitals Leuven; and Belgian Cancer Plan, Ministery of Health.


Fertility and Sterility | 2011

Pregnancy of unknown location: a consensus statement of nomenclature, definitions, and outcome

Kurt T. Barnhart; Norah M. van Mello; Tom Bourne; E. Kirk; Ben Van Calster; C. Bottomley; K. Chung; G. Condous; Steven R. Goldstein; Petra J. Hajenius; Ben Willem J. Mol; T.A. Molinaro; Katherine O'Flynn O'Brien; Richard Husicka; Mary D. Sammel; Dirk Timmerman

OBJECTIVE To improve the interpretation of future studies in women who are initially diagnosed with a pregnancy of unknown location (PUL), we propose a consensus statement with definitions of population, target disease, and final outcome. DESIGN A review of literature and a series of collaborative international meetings were used to develop a consensus for definitions and final outcomes of women initially diagnosed with a PUL. RESULT(S) Global differences were noted in populations studied and in the definitions of outcomes. We propose to define initial ultrasound classification of findings into five categories: definite ectopic pregnancy (EP), probable EP, PUL, probable intrauterine pregnancy (IUP), and definite IUP. Patients with a PUL should be followed and final outcomes should be categorized as visualized EP, visualized IUP, spontaneously resolved PUL, and persisting PUL. Those with the transient condition of a persisting PUL should ultimately be classified as nonvisualized EP, treated persistent PUL, resolved persistent PUL, or histologic IUP. These specific categories can be used to characterize the natural history or location (intrauterine vs. extrauterine) of any early gestation where the initial location is unknown. CONCLUSION(S) Careful definition of populations and classification of outcomes should optimize objective interpretation of research, allow objective assessment of future reproductive prognosis, and hopefully lead to improved clinical care of women initially identified to have a PUL.


Journal of Clinical Oncology | 2008

Prospective Study to Assess Short-Term Intra-Articular and Tenosynovial Changes in the Aromatase Inhibitor–Associated Arthralgia Syndrome

Leilani Morales; Steven Pans; K. Verschueren; Ben Van Calster; Robert Paridaens; Rene Westhovens; Dirk Timmerman; Luc De Smet; Ignace Vergote; Marie-Rose Christiaens; Patrick Neven

PURPOSE Arthralgia is an adverse class effect of aromatase inhibitors (AIs). To date, its exact mechanism remains unclear. The purpose of this study was to investigate the changes in clinical rheumatologic features and magnetic resonance imaging (MRI) of hands and wrists in AI and tamoxifen users. PATIENTS AND METHODS This is a prospective single-center study including 17 consecutive postmenopausal patients with early breast cancer receiving either tamoxifen (n = 5) or an AI (n = 12). At baseline and after 6 months, patients filled in a rheumatologic history questionnaire and a rheumatologic examination including a grip strength test was done. At the same time points, MRI of both hands and wrists was performed. The primary end point was tenosynovial changes from baseline on MRI. Secondary end points were changes from baseline for morning stiffness, grip strength, and intra-articular fluid on MRI. Wilcoxon signed ranks was used to test changes from baseline and the Spearman correlation coefficient to assess the association between rheumatologic and MRI changes from baseline. RESULTS At 6 months, patients on AI had a decrease in grip strength (P = .0049) and an increase in tenosynovial changes (P = .0010). The decrease in grip strength correlated well with the tenosynovial changes on MRI (P = .0074). Only minor changes were seen in patients on tamoxifen. AI users reported worsening of morning stiffness and showed an increase in intra-articular fluid on MRI. CONCLUSION The functional impairment of hands in the AI-associated arthralgia syndrome is characterized by tenosynovial changes on MRI correlating with a significant decrease in hand grip strength.


European Journal of Clinical Investigation | 2012

Assessing the incremental value of diagnostic and prognostic markers: A review and illustration

Ewout W. Steyerberg; Michael J. Pencina; Hester F. Lingsma; Michael W. Kattan; Andrew J. Vickers; Ben Van Calster

Eur J Clin Invest 2011


Lancet Oncology | 2012

Treatment of breast cancer during pregnancy: an observational study

Sibylle Loibl; Sileny Han; Gunter von Minckwitz; Marijke Bontenbal; Alistair Ring; J Giermek; Tanja Fehm; Kristel Van Calsteren; Sabine C. Linn; Bettina Schlehe; Mina Mhallem Gziri; Pj Westenend; Volkmar Müller; Liesbeth Heyns; Brigitte Rack; Ben Van Calster; Nadia Harbeck; Miriam Lenhard; Michael Halaska; Manfred Kaufmann; Valentina Nekljudova; Frédéric Amant

BACKGROUND Little is known about the treatment of breast cancer during pregnancy. We aimed to determine whether treatment for breast cancer during pregnancy is safe for both mother and child. METHODS We recruited patients from seven European countries with a primary diagnosis of breast cancer during pregnancy; data were collected retrospectively if the patient was diagnosed before April, 2003 (when the registry began), or prospectively thereafter, irrespective of the outcome of pregnancy and the type and timing of treatment. The primary endpoint was fetal health for up to 4 weeks after delivery. The registry is ongoing. The study is registered with ClinicalTrials.gov, number NCT00196833. FINDINGS From April, 2003, to December, 2011, 447 patients were registered, 413 of whom had early breast cancer. Median age was 33 years (range 22-51). At the time of diagnosis, median gestational age was 24 weeks (range 5-40). 197 (48%) of 413 women received chemotherapy during pregnancy with a median of four cycles (range one to eight). 178 received an anthracycline, 15 received cyclophosphamide, methotrexate, and fluorouracil, and 14 received a taxane. Birthweight was affected by chemotherapy exposure after adjustment for gestational age (p=0·018), but not by number of chemotherapy cycles (p=0·71). No statistical difference between the two groups was observed for premature deliveries before the 37th week of gestation. 40 (10%) of 386 infants had side-effects, malformations, or new-born complications; these events were more common in infants born before the 37th week of gestation than they were in infants born in the 37th week or later (31 [16%] of 191 infants vs nine [5%] of 195 infants; p=0·0002). In infants for whom maternal treatment was known, adverse events were more common in those who received chemotherapy in utero compared with those who were not exposed (31 [15%] of 203 vs seven [4%] of 170 infants; p=0·00045). Two infants died; both were exposed to chemotherapy and delivered prematurely, but both deaths were thought not to be related to treatment. Median disease-free survival for women with early breast cancer was 70·6 months (95% CI 62·1-105·5) in women starting chemotherapy during pregnancy and 94·4 months (lower 95% CI 64·4; upper 95% CI not yet reached) in women starting chemotherapy after delivery (unadjusted hazard ratio 1·13 [95% CI 0·76-1·69]; p=0·539). INTERPRETATION Although our data show that infants exposed to chemotherapy in utero had a lower birthweight at gestational age than did those who were unexposed, and had more complications, these differences were not clinically significant and, since none of the infants was exposed to chemotherapy in the first trimester, were most likely related to premature delivery. Delay of cancer treatment did not significantly affect disease-free survival for mothers with early breast cancer. Because preterm birth was strongly associated with adverse events, a full-term delivery seems to be of paramount importance. FUNDING BANSS Foundation, Biedenkopf, Germany and the Belgian Cancer Plan, Ministry of Health, Belgium.


Journal of Clinical Oncology | 2013

Prognosis of Women With Primary Breast Cancer Diagnosed During Pregnancy: Results From an International Collaborative Study

Frédéric Amant; Gunter von Minckwitz; Sileny Han; Marijke Bontenbal; Alistair Ring; J Giermek; Hans Wildiers; Tanja Fehm; Sabine C. Linn; Bettina Schlehe; Patrick Neven; Pj Westenend; Volkmar Müller; Kristel Van Calsteren; Brigitte Rack; Valentina Nekljudova; Nadia Harbeck; Michael Untch; Petronella O. Witteveen; Kathrin Schwedler; Christoph Thomssen; Ben Van Calster; Sibylle Loibl

PURPOSE We aimed to determine the prognosis of patients with breast cancer diagnosed during pregnancy (BCP). PATIENTS AND METHODS In this cohort study, a multicentric registry of patients with BCP (from Cancer in Pregnancy, Leuven, Belgium, and GBG 29/BIG 02-03) compiled pro- and retrospectively between 2003 and 2011 was compared with patients who did not have associated pregnancies, using an age limit of 45 years. Patients with a diagnosis postpartum were excluded. The main analysis was performed using Cox proportional hazards regression of disease-free survival (DFS) and overall survival (OS) on exposure (pregnant or not), adjusting for age, stage, grade, hormone receptor status, human epidermal growth factor 2 status, histology, type of chemotherapy, use of trastuzumab, radiotherapy, and hormone therapy. RESULTS The registry contained 447 women with BCP, mainly originating from Germany and Belgium, of whom 311 (69.6%) were eligible for analysis. The nonpregnant group consisted of 865 women. Median age was 33 years for the pregnant and 41 years for the nonpregnant patients. Median follow-up was 61 months. The hazard ratio of pregnancy was 1.34 (95% CI, 0.93 to 1.91; P = .14) for DFS and 1.19 (95% CI, 0.73 to 1.93; P = .51) for OS. Cox regression estimated that the 5-year DFS rate for pregnant patients would have increased from 65% to 71% if these patients had not been pregnant. Likewise, the 5-year OS rate would have increased from 78% to 81%. CONCLUSION The results show similar OS for patients diagnosed with BCP compared with nonpregnant patients. This information is important when patients are counseled and supports the option to start treatment with continuation of pregnancy.


Journal of Clinical Oncology | 2007

Inclusion of CA-125 Does Not Improve Mathematical Models Developed to Distinguish Between Benign and Malignant Adnexal Tumors

Dirk Timmerman; Ben Van Calster; D. Jurkovic; Lil Valentin; Antonia Carla Testa; Jean Pierre Bernard; Caroline Van Holsbeke; Sabine Van Huffel; Ignace Vergote; Tom Bourne

PURPOSE To test the value of serum CA-125 measurements alone or as part of a multimodal strategy to distinguish between malignant and benign ovarian tumors before surgery based on a large prospective multicenter study (International Ovarian Tumor Analysis). PATIENTS AND METHODS Patients with at least one persistent ovarian mass preoperatively underwent transvaginal ultrasonography using gray scale imaging to assess tumor morphology and color Doppler imaging to obtain indices of blood flow. RESULTS Data from 809 patients recruited from nine centers were included in the analysis; 567 patients (70%) had benign tumors and 242 (30%) had malignant tumors-of these 152 were primary invasive (62.8%), 52 were borderline malignant (21.5%), and 38 were metastatic (15.7%). A logistic regression model including CA-125 (M2) resulted in an area under the receiver operating characteristic curve (AUC) of 0.934 and did not outperform a published (M1) without serum CA-125 information (AUC, 0.936). Specifically designed new models including CA-125 for premenopausal women (M3) and for postmenopausal women (M4) did not perform significantly better than the model without CA-125 (M1; AUC, 0.891 v AUC, 0.911 and AUC, 0.975 v AUC, 0.949, respectively). In postmenopausal patients, serum CA-125 alone (AUC, 0.920) and the risk of malignancy index (AUC, 0.924) performed very well. Results were very similar when the models were prospectively tested on a group of 345 new patients with adnexal masses of whom 126 had malignant tumors (37%). CONCLUSION Adding information on CA-125 to clinical information and ultrasound information does not improve discrimination of mathematical models between benign and malignant adnexal masses.


BMJ | 2014

Evaluating the risk of ovarian cancer before surgery using the ADNEX model to differentiate between benign, borderline, early and advanced stage invasive, and secondary metastatic tumours: prospective multicentre diagnostic study.

Ben Van Calster; Kirsten Van Hoorde; Lil Valentin; Antonia Carla Testa; D. Fischerova; Caroline Van Holsbeke; L. Savelli; D. Franchi; E. Epstein; Jeroen Kaijser; Vanya Van Belle; A. Czekierdowski; S. Guerriero; R. Fruscio; Chiara Lanzani; Felice Scala; Tom Bourne; Dirk Timmerman

Objectives To develop a risk prediction model to preoperatively discriminate between benign, borderline, stage I invasive, stage II-IV invasive, and secondary metastatic ovarian tumours. Design Observational diagnostic study using prospectively collected clinical and ultrasound data. Setting 24 ultrasound centres in 10 countries. Participants Women with an ovarian (including para-ovarian and tubal) mass and who underwent a standardised ultrasound examination before surgery. The model was developed on 3506 patients recruited between 1999 and 2007, temporally validated on 2403 patients recruited between 2009 and 2012, and then updated on all 5909 patients. Main outcome measures Histological classification and surgical staging of the mass. Results The Assessment of Different NEoplasias in the adneXa (ADNEX) model contains three clinical and six ultrasound predictors: age, serum CA-125 level, type of centre (oncology centres v other hospitals), maximum diameter of lesion, proportion of solid tissue, more than 10 cyst locules, number of papillary projections, acoustic shadows, and ascites. The area under the receiver operating characteristic curve (AUC) for the classic discrimination between benign and malignant tumours was 0.94 (0.93 to 0.95) on temporal validation. The AUC was 0.85 for benign versus borderline, 0.92 for benign versus stage I cancer, 0.99 for benign versus stage II-IV cancer, and 0.95 for benign versus secondary metastatic. AUCs between malignant subtypes varied between 0.71 and 0.95, with an AUC of 0.75 for borderline versus stage I cancer and 0.82 for stage II-IV versus secondary metastatic. Calibration curves showed that the estimated risks were accurate. Conclusions The ADNEX model discriminates well between benign and malignant tumours and offers fair to excellent discrimination between four types of ovarian malignancy. The use of ADNEX has the potential to improve triage and management decisions and so reduce morbidity and mortality associated with adnexal pathology.

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Dirk Timmerman

Cambridge University Hospitals NHS Foundation Trust

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Sabine Van Huffel

The Catholic University of America

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Tom Bourne

Imperial College London

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Ignace Vergote

Universitaire Ziekenhuizen Leuven

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Ewout W. Steyerberg

Erasmus University Rotterdam

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Caroline Van Holsbeke

Katholieke Universiteit Leuven

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Patrick Neven

Katholieke Universiteit Leuven

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Antonia Carla Testa

Catholic University of the Sacred Heart

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