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Dive into the research topics where R.J. van Klaveren is active.

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Featured researches published by R.J. van Klaveren.


The New England Journal of Medicine | 2009

Management of Lung Nodules Detected by Volume CT Scanning

R.J. van Klaveren; Matthijs Oudkerk; M. Prokop; Ernst Th. Scholten; Kris Nackaerts; Rene Vernhout; C.A. van Iersel; K.A.M. van den Bergh; S. van't Westeinde; C. van der Aalst; Dong Ming Xu; Ying Wang; Yingru Zhao; Hester Gietema; B.J. de Hoop; Hendricus Groen; de Truuske Bock; van Peter Ooijen; Carla Weenink; Johny Verschakelen; J.W.J. Lammers; Wim Timens; D. Willebrand; Annemieke Vink; W.P.T.M. Mali; H.J. de Koning

BACKGROUND The use of multidetector computed tomography (CT) in lung-cancer screening trials involving subjects with an increased risk of lung cancer has highlighted the problem for the clinician of deciding on the best course of action when noncalcified pulmonary nodules are detected by CT. METHODS A total of 7557 participants underwent CT screening in years 1, 2, and 4 of a randomized trial of lung-cancer screening. We used software to evaluate a noncalcified nodule according to its volume or volume-doubling time. Growth was defined as an increase in volume of at least 25% between two scans. The first-round screening test was considered to be negative if the volume of a nodule was less than 50 mm(3), if it was 50 to 500 mm(3) but had not grown by the time of the 3-month follow-up CT, or if, in the case of those that had grown, the volume-doubling time was 400 days or more. RESULTS In the first and second rounds of screening, 2.6% and 1.8% of the participants, respectively, had a positive test result. In round one, the sensitivity of the screen was 94.6% (95% confidence interval [CI], 86.5 to 98.0) and the negative predictive value 99.9% (95% CI, 99.9 to 100.0). In the 7361 subjects with a negative screening result in round one, 20 lung cancers were detected after 2 years of follow-up. CONCLUSIONS Among subjects at high risk for lung cancer who were screened in three rounds of CT scanning and in whom noncalcified pulmonary nodules were evaluated according to volume and volume-doubling time, the chances of finding lung cancer 1 and 2 years after a negative first-round test were 1 in 1000 and 3 in 1000, respectively. (Current Controlled Trials number, ISRCTN63545820.)


British Journal of Cancer | 2002

Multicentre phase II study of gemcitabine and cisplatin in malignant pleural mesothelioma

J.W van Haarst; P. Baas; Christian Manegold; J H Schouwink; Jacobus A. Burgers; H.G de Bruin; W J Mooi; R.J. van Klaveren; M.J.A. de Jonge; J. Van Meerbeeck

Malignant pleural mesothelioma is a notoriously chemoresistant tumour. However, a recent single institution study showed an impressive activity of gemcitabine and cisplatin. Our aim is to investigate the efficacy and toxicity of a gemcitabine and cisplatin combination in selected and chemo-naive patients with histologically proven malignant pleural mesothelioma. Method: Gemcitabine 1250 mg m−2 was administered on day 1 and day 8 and cisplatin 80 mg m−2 was administered on day 1 in a 3-week cycle with a maximum of six cycles. Response and toxicity evaluations were performed according to WHO and NCIC-CTC criteria. Pathology and radiology were centrally reviewed. Results show that in 25 evaluable patients, four PR were observed (ORR 16%, 95% CI 1–31%). Responses of seven patients were unevaluable. No unexpected toxicity occurred. Time to progression was 6 months (5–7 months) with a median survival from registration of 9.6 months (95% CI 8–12 months). In conclusion this trial excludes with 90% power a response rate of greater than 30% in patients with malignant pleural mesothelioma using a combination of gemcitabine and cisplatin at the proposed dose and schedule.


Acta Oncologica | 2006

Lung tumor tracking during stereotactic radiotherapy treatment with the CyberKnife: Marker placement and early results

Joost J. Nuyttens; J.-B. Prévost; J. Praag; Mischa S. Hoogeman; R.J. van Klaveren; Peter C. Levendag; Peter M. T. Pattynama

Lung tumor tracking during stereotactic radiotherapy with the CyberKnife requires the insertion of markers in or close to the tumor. To reduce the risk of pneumothorax, three methods of marker placement were used: 1) intravascular coil placement, 2) percutaneous intrathoracal, and 3) percutaneous extrathoracal placement. We investigated the toxicity of marker placement and the tumor response of the lung tumor tracking treatment. Markers were placed in 20 patients with 22 tumors: 13 patients received a curative treatment, seven a palliative. The median Charlson Comorbidity Score was 4 (range: 1–8). Platinum fiducials and intravascular embolisation coils were used as markers. In total, 78 markers were placed: 34 intrathoracal, 23 intravascular and 21 extrathoracal. The PTV equaled the GTV + 5 mm. A median dose of 45 Gy (range: 30–60 Gy, in 3 fractions) was prescribed to the 70–85% isodose. The response was evaluated with a CTscan performed 6–8 weeks after the last treatment and routinely thereafter. The median follow-up was 4 months (range: 2–11). No severe toxicity due to the marker placement was seen. Pneumothorax was not seen. The local control was 100%. Four tumors in four patients showed a complete response, 15 tumors in 14 patients a partial response, and three tumors in two patients with metastatic disease had stable disease. No severe toxicity of marker placement was seen due to the appropriate choice of one of the three methods. CyberKnife tumor tracking with markers is feasible and resulted in excellent tumor response. Longer follow-up is needed to validate the local control.


Thorax | 2011

CT-quantified emphysema in male heavy smokers: association with lung function decline

F. A. A. Mohamed Hoesein; B.J. de Hoop; Pieter Zanen; Hester Gietema; Cas Kruitwagen; B. van Ginneken; Ivana Išgum; C. Mol; R.J. van Klaveren; Arie Dijkstra; Hjm Groen; H. M. Boezen; D. S. Postma; Mathias Prokop; J.W.J. Lammers

Background Emphysema and small airway disease both contribute to chronic obstructive pulmonary disease (COPD), a disease characterised by accelerated decline in lung function. The association between the extent of emphysema in male current and former smokers and lung function decline was investigated. Methods Current and former heavy smokers participating in a lung cancer screening trial were recruited to the study and all underwent CT. Spirometry was performed at baseline and at 3-year follow-up. The 15th percentile (Perc15) was used to assess the severity of emphysema. Results 2085 men of mean age 59.8 years participated in the study. Mean (SD) baseline Perc15 was −934.9 (19.5) HU. A lower Perc15 value correlated with a lower forced expiratory volume in 1 s (FEV1) at baseline (r=0.12, p<0.001). Linear mixed model analysis showed that a lower Perc15 was significantly related to a greater decline in FEV1 after follow-up (p<0.001). Participants without baseline airway obstruction who developed it after follow-up had significantly lower mean (SD) Perc15 values at baseline than those who did not develop obstruction (−934.2 (17.1) HU vs −930.2 (19.7) HU, p<0.001). Conclusion Greater baseline severity of CT-detected emphysema is related to lower baseline lung function and greater rates of lung function decline, even in those without airway obstruction. CT-detected emphysema aids in identifying non-obstructed male smokers who will develop airflow obstruction.


British Journal of Cancer | 2010

Short-term health-related quality of life consequences in a lung cancer CT screening trial (NELSON)

K.A.M. van den Bergh; Marie-Louise Essink-Bot; Gerard J. J. M. Borsboom; E. Th Scholten; Mathias Prokop; H.J. de Koning; R.J. van Klaveren

Background:In lung cancer CT screening, participants often have an indeterminate screening result at baseline requiring a follow-up CT. In subjects with either an indeterminate or a negative result after screening, we investigated whether health-related quality of life (HRQoL) changed over time and differed between groups in the short term.Methods:A total of 733 participants in the NELSON trial received four questionnaires: T0, before randomisation; T1, 1 week before the baseline screening; T2, 1 day after the screening; and T3, 2 months after the screening results but before the 3-month follow-up CT. HRQoL was measured as generic HRQoL (the 12-item Short Form, SF-12; the EuroQol questionnaire, EQ-5D), anxiety (the Spielberger State-Trait Anxiety Inventory, STAI-6), and lung-cancer-specific distress (the Impact of Event Scale, IES). For analyses, repeated-measures analysis of variance was used, adjusted for covariates.Results:Response to each questionnaire was 88% or higher. Scores on SF-12, EQ-5D, and STAI-6 showed no clinically relevant changes over time. At T3, IES scores that were clinically relevant increased after an indeterminate result, whereas these scores showed a significant decrease after a negative result. At T3, differences in IES scores between the two baseline result groups were both significant and clinically relevant (P<0.01).Conclusion:This longitudinal study among participants of a lung cancer screening programme showed that in the short term recipients of an indeterminate result experienced increased lung-cancer-specific distress, whereas the HRQoL changes after a negative baseline screening result may be interpreted as a relief.


European Respiratory Journal | 2011

Long-term effects of lung cancer computed tomography screening on health-related quality of life: the NELSON trial

K.A.M. van den Bergh; Marie-Louise Essink-Bot; Gerard J. J. M. Borsboom; Ernst Th. Scholten; R.J. van Klaveren; H.J. de Koning

The long-term effects of lung cancer computed tomography (CT) screening on health-related quality of life (HRQoL) have not yet been investigated. In the Dutch–Belgian Randomised Lung Cancer Screening Trial (NELSON trial), 1,466 participants received questionnaires before randomisation (T0), 2 months after baseline screening (screen group only; T1) and at 2-yr follow-up (T2). HRQoL was measured as generic HRQoL (12-item short-form questionnaire and EuroQoL questionnaire), anxiety (Spielberger State-Trait Anxiety Inventory) and lung cancer-specific distress (impact of event scale (IES)). Repeated measures of ANOVA were used to analyse differences between the screen and control groups, and between indeterminate (requiring a follow-up CT) and negative screening result groups. At T0 and T2 there were no significant differences in HRQoL scores over time between the screen and control groups, or between the indeterminate or negative second-round screening result group. There was a temporary increase in IES scores after an indeterminate baseline result (T0: mean 4.0 (95% CI 2.8–5.3); T1: mean 7.8 (95% CI 6.5–9.0); T2: mean 4.5 (95% CI 3.3–5.8)). At 2-yr follow-up, the HRQoL of screened subjects was similar to that of control subjects, the unfavourable short-term effects of an indeterminate baseline screening result had resolved and an indeterminate result at the second screening round had no impact on HRQoL.


Radiology | 2008

Effect of nodule characteristics on variability of semiautomated volume measurements in pulmonary nodules detected in a lung cancer screening program.

Ying Wang; R.J. van Klaveren; H. J. van der Zaag-Loonen; de Truuske Bock; Hester Gietema; Dong Ming Xu; Anne Leusveld; H.J. de Koning; Ernst Th. Scholten; Johny Verschakelen; Mathias Prokop; Matthijs Oudkerk

PURPOSE To retrospectively assess volume measurement variability in solid pulmonary nodules (volume, 15-500 mm(3)) detected at lung cancer screening and to quantify the independent effects of nodule morphology, size, and location. MATERIALS AND METHODS This retrospective study was a substudy of the screening program that was approved by the Dutch Ministry of Health, and all participants provided written informed consent. Two independent readers used semiautomated software to measure the volume of pulmonary nodules detected in 6774 participants aged 50-75 years (5917 men). Nodules were classified according to their location (purely intraparenchymal, pleural based, juxtavascular, or fissure attached), morphology (smooth, polylobulated, spiculated, or irregular), and size (<or=50 mm(3) or >50 mm(3)). The level of agreement was expressed by using the absolute values of the relative volume differences (RVDs). Multivariate logistic regression analysis was performed, and odds ratios (ORs) were computed to quantify the independent effects of morphology, location, and size on RVD categories. RESULTS Altogether, 4225 nodules in 2239 participants were included. Complete agreement in volume was obtained for 3646 (86%) of the nodules. Disagreement was small (absolute value of RVD < 5%) for 173 (4%) nodules, moderate (absolute value of RVD >or= 5% but < 15%) for 232 (6%), and large (absolute value of RVD >or= 15%) for 174 (4%). Multivariate analysis showed that the ORs of volume disagreement were 15.7, 3.1, and 1.9 for irregular, spiculated, and polylobulated nodules, respectively; 3.5, 2.6, and 2.1 for juxtavascular, pleural-based, and fissure-attached nodules, respectively; and 1.3 for large nodules compared with smooth, purely intraparenchymal, and small reference nodules. CONCLUSION Nodule morphology, location, and size influence volume measurement variability, particularly for juxtavascular and irregular nodules.


European Radiology | 2007

Neglectable benefit of searching for incidental findings in the Dutch-Belgian lung cancer screening trial (NELSON) using low-dose multidetector CT

J. C. M. van de Wiel; Y. Wang; Dong Ming Xu; H. J. van der Zaag-Loonen; E. van der Jagt; R.J. van Klaveren; Matthijs Oudkerk

The purpose of this study was to prospectively determine the frequency and spectrum of incidental findings (IFs) and their clinical implications in a high risk population for lung cancer undergoing low-dose multidetector computed tomography (MDCT) screening for lung cancer. Scans of 1,929 participants were evaluated for lung lesions and IFs by two radiologists. IFs were categorised as not clinically relevant or possibly clinically relevant. Findings were considered possibly clinically relevant if they could require further evaluation or could have substantial clinical implications. All possibly clinically relevant IFs were reviewed by a third radiologist, who determined its clinical relevance. Of all 1,929 participants, 1,410 (73%) had not clinically relevant IFs and 163 (8%) had possibly clinically relevant IFs of which 129 (79%) were indeed considered clinically relevant. Additional imaging was performed mainly by ultrasound (112 of 118, 96%). All but one lesion were concluded to be benign, mostly cysts (n = 115, 80%). Only 21 (1%) participants had findings with clinical implications. In one participant a malignancy was found, yet without any clinical benefit since no curative treatment was possible. Based on our results, we advise against systematically searching for and reporting of IFs in lung cancer screening studies using low-dose MDCT.


European Respiratory Journal | 2011

The impact of a lung cancer computed tomography screening result on smoking abstinence

C.M. van der Aalst; R.J. van Klaveren; K.A.M. van den Bergh; Marc C. Willemsen; H.J. de Koning

Receiving a lung cancer computed tomography screening result might be a teachable moment for smoking cessation, but it might also unintentionally reassure smokers to continue smoking. The objective of the present study was to investigate whether test results were associated with smoking abstinence in the Dutch–Belgian Randomised Controlled Lung Cancer Screening Trial (NELSON trial). Two random samples of male smokers who had received either only negative test results (n = 550) or one or more indeterminate test result (n = 440) were sent a questionnaire 2 yrs after randomisation. Smokers with an indeterminate result reported more quit attempts (p = 0.02), but the prolonged abstinence rate in smokers receiving a negative test (46 (8.9%) out of 519 subjects) was comparable with the abstinence rate in smokers with one or more indeterminate results (48 (11.5%) out of 419 subjects) (p = 0.19). A statistically insignificant increase was found after one or more indeterminate test result (10.9 and 15.0%, respectively) compared with receiving only negative test results (8.9%) (p = 0.26). In conclusion, the outcome of the screening test had no impact on future smoking abstinence in male smokers, although all results suggest more favourable implications after one or more follow-up recommendations. Screening test outcomes could be used as a teachable moment for smoking cessation.


European Respiratory Journal | 2001

Lung cancer screening by low-dose spiral computed tomography.

R.J. van Klaveren; Jdf Habbema; Jesper Holst Pedersen; H.J. de Koning; Matthijs Oudkerk; Henk C. Hoogsteden

The poor prognosis of lung cancer has barely changed in the last decades, but the prognosis is better when the disease is detected earlier. Lung cancer screening by chest radiography did not lead to a decrease in lung cancer mortality, presumably because the chest radiograph is a poor screening tool with low sensitivity. With the advent of the low-dose spiral computed tomography (CT) scan it has become feasible to detect early invasive stage I lung cancer in 8-90% of cases. This technique could possibly decrease lung cancer mortality, but the extent of this effect is as yet unknown, and whether lung cancer screening will be cost-effective is yet to be determined. These questions can only be resolved in a randomized controlled trial with lung cancer mortality as an unbiased end-point. In this review, the initiatives to evaluate low dose spiral CT screening for lung cancer in Japan, USA and Europe are presented. In the USA and Japan, evaluation is in one-armed studies, whereas in many European countries randomized trials are now being planned and several one-armed studies have been initiated. A formal collaboration among these countries has now been set up. It is strongly recommended that lung cancer screening be evaluated in randomized trials in order to allow evidence-based health policy decisions to be made on this subject.

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H.J. de Koning

Erasmus University Rotterdam

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Matthijs Oudkerk

University Medical Center Groningen

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Rene Vernhout

Erasmus University Rotterdam

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Joachim Aerts

Erasmus University Rotterdam

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Mathias Prokop

Radboud University Nijmegen

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Maurits Demedts

Katholieke Universiteit Leuven

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