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Featured researches published by Jeroen Liesker.


Annals of Oncology | 2012

Circulating tumor cells in small-cell lung cancer: a predictive and prognostic factor

Thijo J. N. Hiltermann; Milind M. Pore; A. P. van den Berg; Wim Timens; H. M. Boezen; Jeroen Liesker; J. H. Schouwink; W. J. A. Wijnands; Gerald S. M. A. Kerner; Frank A.E. Kruyt; H. Tissing; Arjan G.J. Tibbe; Leonardus Wendelinus Mathias Marie Terstappen; Harry J.M. Groen

BACKGROUND Initial response of small-cell lung cancer (SCLC) to chemotherapy is high, and recurrences occur frequently, leading to early death. This study investigated the prognostic value of circulating tumor cells (CTCs) in patients with SCLC and whether changes in CTCs can predict response to chemotherapy. Patients and methods In this multicenter prospective study, blood samples for CTC analysis were obtained from 59 patients with SCLC before, after one cycle, and at the end of chemotherapy. CTCs were measured using CellSearch systems. RESULTS At baseline, lower numbers of CTCs were observed for 21 patients with limited SCLC (median = 6, range 0-220) compared with 38 patients with extensive stage (median = 63, range 0-14,040). Lack of measurable CTCs (27% of patients) was associated with prolonged survival (HR 3.4; P ≤ 0.001). CTCs decreased after one cycle of chemotherapy; this decrease was not associated with tumor response after four cycles of chemotherapy. CTC count after the first cycle of chemotherapy was the strongest predictor for overall survival (HR 5.7; 95% CI 1.7-18.9; P = 0.004). CONCLUSION Absolute CTCs after one cycle of chemotherapy in patients with SCLC is the strongest predictor for response on chemotherapy and survival. Patients with low initial CTC numbers lived longer than those with higher CTCs.BACKGROUND Initial response of small-cell lung cancer (SCLC) to chemotherapy is high, and recurrences occur frequently, leading to early death. This study investigated the prognostic value of circulating tumor cells (CTCs) in patients with SCLC and whether changes in CTCs can predict response to chemotherapy. PATIENTS AND METHODS In this multicenter prospective study, blood samples for CTC analysis were obtained from 59 patients with SCLC before, after one cycle, and at the end of chemotherapy. CTCs were measured using CellSearch® systems. RESULTS At baseline, lower numbers of CTCs were observed for 21 patients with limited SCLC (median = 6, range 0-220) compared with 38 patients with extensive stage (median = 63, range 0-14 040). Lack of measurable CTCs (27% of patients) was associated with prolonged survival (HR 3.4; P ≤ 0.001). CTCs decreased after one cycle of chemotherapy; this decrease was not associated with tumor response after four cycles of chemotherapy. CTC count after the first cycle of chemotherapy was the strongest predictor for overall survival (HR 5.7; 95% CI 1.7-18.9; P = 0.004). CONCLUSION Absolute CTCs after one cycle of chemotherapy in patients with SCLC is the strongest predictor for response on chemotherapy and survival. Patients with low initial CTC numbers lived longer than those with higher CTCs.


International Journal of Chronic Obstructive Pulmonary Disease | 2009

Change in inflammation in out-patient COPD patients from stable phase to a subsequent exacerbation

Erik Bathoorn; Jeroen Liesker; Dirkje S. Postma; Gerard H. Koëter; Marco van der Toorn; Sicco van der Heide; H. Alec Ross; Antoon J. M. van Oosterhout; Huib Kerstjens

Background Inflammation increases during exacerbations of COPD, but only a few studies systematically assessed these changes. Better identification of these changes will increase our knowledge and potentially guide therapy, for instance by helping with quicker distinction of bacterially induced exacerbations from other causes. Aim To identify which inflammatory parameters increase during COPD exacerbations compared to stable disease, and to compare bacterial and non-bacterial exacerbations. Methods In 45 COPD patients (37 male/8 female, 21 current smokers, mean age 65, FEV1 52% predicted, pack years 38) sputum was collected during a stable phase and subsequently during an exacerbation. Results Sputum total cell counts (9.0 versus 7.9 × 106/mL), eosinophils (0.3 versus 0.2 × 106/mL), neutrophils (6.1 versus 5.8 × 106/mL), and lymphocytes (0.07 versus 0.02 × 106/mL) increased significantly during an exacerbation compared to stable disease. A bacterial infection was demonstrated by culture in 8 sputum samples obtained during an exacerbation. These exacerbations had significantly increased sputum total cell and neutrophil counts, leukotriene-B4, myeloperoxidase, interleukin-8 and interleukin-6, and tumor necrosis factor-α (TNF-α) levels, and were also associated with more systemic inflammation compared to exacerbations without a bacterial infection. Sputum TNF-α level during an exacerbation had the best test characteristics to predict a bacterial infection. Conclusion Sputum eosinophil, neutrophil, and lymphocyte counts increase during COPD exacerbations. The increase in systemic inflammation during exacerbations seems to be limited to exacerbations caused by bacterial infections of the lower airways. Sputum TNF-α is a candidate marker for predicting airway bacterial infection.


Respiratory Medicine | 2011

Sputum inflammation predicts exacerbations after cessation of inhaled corticosteroids in COPD

Jeroen Liesker; Erik Bathoorn; Dirkje S. Postma; Judith M. Vonk; Wim Timens; Huib Kerstjens

INTRODUCTION The GOLD guidelines advocate not to institute inhaled corticosteroids (ICS) in patients with mild-to-moderate COPD. However, many patients do use ICS and in some patients, withdrawal is associated with deteriorating lung function and increased exacerbation rates. Unfortunately, physicians do not know in which patients they can stop ICS treatment safely. AIM To identify predictors of COPD exacerbations after ICS withdrawal. METHODS During ICS treatment, post-bronchodilator spirometry, body plethysmography, and health status assessment were performed in 68 COPD patients using ICS. Additionally, sputum cell differentials, supernatant leukotriene B(4), eosinophilic cationic protein, and myeloperoxidase, serum C-reactive protein and soluble intracellular adhesion molecule, and urinary desmosine were assessed. Sputum was also analysed for mRNA levels of haemoxygenase-1, tumour necrosis factor-α, RANTES, interleukin 5(IL-5), IL-10, IL-12, IL-13, transforming growth factor-β, and interferon-γ. STATISTICS Cox regression analyses were performed using time to exacerbation as outcome variable to identify significant hazards for a COPD exacerbation after ICS withdrawal. RESULTS Higher sputum % eosinophils, higher sputum MPO/neutrophil level, longer duration of COPD symptoms, <40 packyears smoking, and ICS withdrawal in November, December or January were significant hazards (all p<0.05) for experiencing a COPD exacerbation after ICS withdrawal in a monovariate model. In a multivariate model, all factors proved independent predictors except for sputum MPO/neutrophil level. CONCLUSIONS Decisions on whether or not inhaled corticosteroids can be safely withdrawn in mild-to-moderate COPD can be facilitated by assessment of sputum inflammation, particularly eosinophil numbers, next to packyears smoking, season, and duration of COPD symptoms.


International Journal of Chronic Obstructive Pulmonary Disease | 2009

Reticular basement membrane in asthma and COPD: Similar thickness, yet different composition

Jeroen Liesker; Nick H. T. ten Hacken; Mieke Zeinstra-Smith; S. R. Rutgers; Dirkje S. Postma; Wim Timens

Background Reticular basement membrane (RBM) thickening has been variably associated with asthma and chronic obstructive pulmonary disease (COPD). Even if RBM thickness is similar in both diseases, its composition might still differ. Objective To assess whether RBM thickness and composition differ between asthma and COPD. Methods We investigated 24 allergic asthmatics (forced expiratory volume in one second [FEV1] 92% predicted), and 17 nonallergic COPD patients (FEV1 60% predicted), and for each group a control group of similar age and smoking habits (12 and 10 persons, respectively). Snap-frozen sections of bronchial biopsies were stained with hematoxylin/eosin and for collagen I, III, IV, V, laminin and tenascin. RBM thickening was assessed by digital image analysis. Relative staining intensity of each matrix component was determined. Results Mean (SD) RBM thickness was not significantly different between asthma and COPD 5.5 (1.3) vs 6.0 (1.8) μm, but significantly larger than in their healthy counterparts, ie, 4.7 (0.9) and 4.8 (1.2) μm, respectively. Collagen I and laminin stained significantly stronger in asthma than in COPD. Tenascin stained stronger in asthma than in healthy controls of similar age, and stronger in COPD controls than in asthma controls (p < 0.05). Conclusion RBM thickening occurs both in asthma and COPD. We provide supportive evidence that its composition differs in asthma and COPD.


COPD: Journal of Chronic Obstructive Pulmonary Disease | 2008

Anti-Inflammatory Effects of Combined Budesonide/Formoterol in COPD Exacerbations

Erik Bathoorn; Jeroen Liesker; Dirkje S. Postma; Martin Boorsma; Eva Bondesson; Gerard H. Koëter; Henk F. Kauffman; Antoon J. M. van Oosterhout; Huib Kerstjens

Systemic corticosteroids and additional short-acting ββ2-agonists are commonly used in exacerbations of chronic obstructive pulmonary disease (COPD). In this double-blind study, the combination of a high-dose inhaled corticosteroid with a rapid-onset long-acting ββ2-agonist was evaluated in the treatment of out-patient COPD exacerbations. The primary aim was to compare 14-day treatment effects of budesonide/formoterol to placebo on sputum eosinophils and, secondarily, on other indices of inflammation, forced expiratory flow in one second (FEV1), symptoms, health status, and adverse events. Forty-five patients not using steroids (37 male, 21/24 current/ex smoker, median packyears 38, age 65 years, FEV1 61% predicted), experiencing a COPD exacerbation, were treated at home with budesonide/formoterol (320/9 μg 4 times daily), prednisolone (30 mg daily), or placebo for 14 days. Sputum eosinophils were significantly reduced by budesonide/formoterol (−57%) compared to placebo (+24%) (p = 0.01). Budesonide/formoterol reduced total symptom scores significantly (p = 0.01) compared to placebo. The increase in FEV1 by 2 weeks of treatment with budesonide/formoterol (125 ml) was not significantly different from that of placebo (43 ml) (p = 0.07). Budesonide/ formoterol treatment did not suppress morning serum cortisol compared to placebo (−16 %; p = 0.50). In conclusion, budesonide/formoterol reduces sputum eosinophils and improves symptoms in the treatment of out-patient COPD exacerbations.


PLOS ONE | 2013

Common and rare EGFR and KRAS mutations in a Dutch non-small-cell lung cancer population and their clinical outcome

Gerald S. M. A. Kerner; Ed Schuuring; Johanna Sietsma; Thijo J. N. Hiltermann; Remge M. Pieterman; Gerard P. J. de Leede; John W.G. van Putten; Jeroen Liesker; Tineke E. J. Renkema; Peter van Hengel; Inge Platteel; Wim Timens; Harry J.M. Groen

Introduction In randomly assigned studies with EGFR TKI only a minor proportion of patients with NSCLC have genetically profiled biopsies. Guidelines provide evidence to perform EGFR and KRAS mutation analysis in non-squamous NSCLC. We explored tumor biopsy quality offered for mutation testing, different mutations distribution, and outcome with EGFR TKI. Patient and Methods Clinical data from 8 regional hospitals were studied for patient and tumor characteristics, treatment and overall survival. Biopsies sent to the central laboratory were evaluated for DNA quality and subsequently analyzed for mutations in exons 18–21 of EGFR and exon 2 of KRAS by bidirectional sequence analysis. Results Tumors from 442 subsequent patients were analyzed. For 74 patients (17%) tumors were unsuitable for mutation analysis. Thirty-eight patients (10.9%) had EGFR mutations with 79% known activating mutations. One hundred eight patients (30%) had functional KRAS mutations. The mutation spectrum was comparable to the Cosmic database. Following treatment in the first or second line with EGFR TKI median overall survival for patients with EGFR (n = 14), KRAS (n = 14) mutations and wild type EGFR/KRAS (n = 31) was not reached, 20 and 9 months, respectively. Conclusion One out of every 6 tumor samples was inadequate for mutation analysis. Patients with EGFR activating mutations treated with EGFR-TKI have the longest survival.


Respiratory Medicine | 2004

Cognitive performance in patients with COPD

Jeroen Liesker; Dirkje S. Postma; Rypko J Beukema; Nick H. T. ten Hacken; Thys van der Molen; Roland Riemersma; Ed H van Zomeren; Huib Kerstjens


Chest | 2002

A Systematic Review of the Effects of Bronchodilators on Exercise Capacity in Patients With COPD

Jeroen Liesker; Peter J. Wijkstra; Nick H. T. ten Hacken; Gerard H. Koëter; Dirkje S. Postma; Huib Kerstjens


Chest | 2007

Safety of Sputum Induction During Exacerbations of COPD

Erik Bathoorn; Jeroen Liesker; Dirkje S. Postma; Gerard H. Koëter; Antoon J. M. van Oosterhout; Huib Kerstjens


Respiratory Medicine | 2007

Mast cell numbers in airway smooth muscle and PC20AMP in asthma and COPD

Jeroen Liesker; ten Nicolaas Hacken; S. R. Rutgers; Mieke Zeinstra-Smith; Dirkje S. Postma; Wim Timens

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Dirkje S. Postma

University Medical Center Groningen

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Huib Kerstjens

University Medical Center Groningen

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Mieke Zeinstra-Smith

University Medical Center Groningen

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S. R. Rutgers

University Medical Center Groningen

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Wim Timens

University Medical Center Groningen

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Nick H. T. ten Hacken

University Medical Center Groningen

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Erik Bathoorn

University Medical Center Groningen

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Gerard H. Koëter

University Medical Center Groningen

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Harry J.M. Groen

University Medical Center Groningen

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Thijo J. N. Hiltermann

University Medical Center Groningen

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