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Dive into the research topics where Erik van Werkhoven is active.

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Featured researches published by Erik van Werkhoven.


Lancet Oncology | 2015

Stereotactic ablative radiotherapy versus lobectomy for operable stage I non-small-cell lung cancer: a pooled analysis of two randomised trials

Joe Y. Chang; Suresh Senan; Marinus A. Paul; Reza J. Mehran; Alexander V. Louie; P Balter; Harry J.M. Groen; Stephen E. McRae; Joachim Widder; Lei Feng; Ben E.E.M. van den Borne; Mark F. Munsell; Coen W. Hurkmans; Donald A. Berry; Erik van Werkhoven; John J. Kresl; Anne-Marie C. Dingemans; Omar Dawood; Cornelis J.A. Haasbeek; Larry S. Carpenter; Katrien De Jaeger; Ritsuko Komaki; Ben J. Slotman; Egbert F. Smit; Jack A. Roth

BACKGROUNDnThe standard of care for operable, stage I, non-small-cell lung cancer (NSCLC) is lobectomy with mediastinal lymph node dissection or sampling. Stereotactic ablative radiotherapy (SABR) for inoperable stage I NSCLC has shown promising results, but two independent, randomised, phase 3 trials of SABR in patients with operable stage I NSCLC (STARS and ROSEL) closed early due to slow accrual. We aimed to assess overall survival for SABR versus surgery by pooling data from these trials.nnnMETHODSnEligible patients in the STARS and ROSEL studies were those with clinical T1-2a (<4 cm), N0M0, operable NSCLC. Patients were randomly assigned in a 1:1 ratio to SABR or lobectomy with mediastinal lymph node dissection or sampling. We did a pooled analysis in the intention-to-treat population using overall survival as the primary endpoint. Both trials are registered with ClinicalTrials.gov (STARS: NCT00840749; ROSEL: NCT00687986).nnnFINDINGSn58 patients were enrolled and randomly assigned (31 to SABR and 27 to surgery). Median follow-up was 40·2 months (IQR 23·0-47·3) for the SABR group and 35·4 months (18·9-40·7) for the surgery group. Six patients in the surgery group died compared with one patient in the SABR group. Estimated overall survival at 3 years was 95% (95% CI 85-100) in the SABR group compared with 79% (64-97) in the surgery group (hazard ratio [HR] 0·14 [95% CI 0·017-1·190], log-rank p=0·037). Recurrence-free survival at 3 years was 86% (95% CI 74-100) in the SABR group and 80% (65-97) in the surgery group (HR 0·69 [95% CI 0·21-2·29], log-rank p=0·54). In the surgery group, one patient had regional nodal recurrence and two had distant metastases; in the SABR group, one patient had local recurrence, four had regional nodal recurrence, and one had distant metastases. Three (10%) patients in the SABR group had grade 3 treatment-related adverse events (three [10%] chest wall pain, two [6%] dyspnoea or cough, and one [3%] fatigue and rib fracture). No patients given SABR had grade 4 events or treatment-related death. In the surgery group, one (4%) patient died of surgical complications and 12 (44%) patients had grade 3-4 treatment-related adverse events. Grade 3 events occurring in more than one patient in the surgery group were dyspnoea (four [15%] patients), chest pain (four [15%] patients), and lung infections (two [7%]).nnnINTERPRETATIONnSABR could be an option for treating operable stage I NSCLC. Because of the small patient sample size and short follow-up, additional randomised studies comparing SABR with surgery in operable patients are warranted.nnnFUNDINGnAccuray Inc, Netherlands Organisation for Health Research and Development, NCI Cancer Center Support, NCI Clinical and Translational Science Award.


Investigational New Drugs | 2015

Phase I/II study with ruthenium compound NAMI-A and gemcitabine in patients with non-small cell lung cancer after first line therapy

Suzanne Leijen; Sjaak Burgers; Paul Baas; Dick Pluim; Matthijs M. Tibben; Erik van Werkhoven; Enzo Alessio; Gianni Sava; Jos H. Beijnen; Jan H. M. Schellens

SummaryBackground This phase I/II study determined the maximal tolerable dose, dose limiting toxicities, antitumor activity, the pharmacokinetics and pharmacodynamics of ruthenium compound NAMI-A in combination with gemcitabine in Non-Small Cell Lung Cancer patients after first line treatment. Methods Initial dose escalation of NAMI-A was performed in a 28xa0day cycle: NAMI-A as a 3xa0h infusion through a port-a-cath at a starting dose of 300xa0mg/m2 at day 1, 8 and 15, in combination with gemcitabine 1,000xa0mg/m2 at days 2, 9 and 16. Subsequently, dose escalation of NAMI-A in a 21xa0day schedule was explored. At the maximal tolerable dose level of this schedule an expansion group was enrolled of which 15 patients were evaluable for response. Results Due to frequent neutropenic dose interruptions in the third week, the 28xa0day schedule was amended into a 21xa0day schedule. The maximal tolerable dose was 300 and 450xa0mg/m2 of NAMI-A (21xa0day schedule). Main adverse events consisted of neutropenia, anemia, elevated liver enzymes, transient creatinine elevation, nausea, vomiting, constipation, diarrhea, fatigue, and renal toxicity. Conclusion NAMI-A administered in combination with gemcitabine is only moderately tolerated and less active in NSCLC patients after first line treatment than gemcitabine alone.


European Urology | 2010

Prognostic Factors for Occult Inguinal Lymph Node Involvement in Penile Carcinoma and Assessment of the High-Risk EAU Subgroup: A Two-Institution Analysis of 342 Clinically Node-Negative Patients

Niels M. Graafland; Wayne Lam; Joost A.P. Leijte; Tet Yap; Maarten P.W. Gallee; Cathy Corbishley; Erik van Werkhoven; Nick Watkin; Simon Horenblas

BACKGROUNDnThe European Association of Urology (EAU) guidelines advise an elective bilateral lymphadenectomy in clinically node-negative (cN0) patients with high-risk penile carcinoma (≥pT2, G3, or lymphovascular invasion [LVI]).nnnOBJECTIVEnOur aim was to assess prognostic factors for occult metastasis and to determine whether current EAU guidelines accurately stratify patients at high risk.nnnDESIGN, SETTING, AND PARTICIPANTSnData of 342 cN0 patients with histologically proven invasive penile squamous cell carcinoma who had undergone the current dynamic sentinel node biopsy (DSNB) protocol were analysed. A complete ipsilateral inguinal lymphadenectomy was only done if the sentinel node was tumour positive.nnnMEASUREMENTSnThe presence of occult metastasis was established by preoperative ultrasound and tumour-positive fine-needle aspiration cytology, tumour-positive sentinel nodes, and groin metastases during follow-up after a negative DSNB procedure. Median follow-up was 31 mo.nnnRESULTS AND LIMITATIONSnSixty-eight of 342 patients (20%) and 87 of 684 groins (13%) had occult nodal involvement including 6 patients (2%) with a groin metastasis after negative DSNB. Corpus spongiosum invasion, corpus cavernosum invasion, histologic grade, and LVI were each significant prognosticators for occult metastasis on univariate analysis. On multivariate analysis, grade (odds ratio [OR]: 3.3 for intermediate and 4.9 for poor, respectively) and LVI (OR: 2.2) remained predictive factors. In total, 245 patients (72%) were classified high risk according to EAU guidelines. Among them, the incidence of occult metastasis was 23% (57 of 245). A potential limitation of this study is the lack of external review.nnnCONCLUSIONSnHistologic grade and LVI are independent prognostic factors for occult metastasis in penile carcinoma. Although both predictors are incorporated into the current EAU guidelines, the stratification of patients needing a lymph node dissection is inaccurate. Approximately 77% of high-risk patients (188 of 245) would have had a negative bilateral inguinal lymphadenectomy. For the time being, DSNB is considered a more suitable staging method than EAU risk stratification for an accurate determination of patients who require lymph node dissection.


The Journal of Urology | 2010

Prognostic Significance of Extranodal Extension in Patients With Pathological Node Positive Penile Carcinoma

Niels M. Graafland; Hester van Boven; Erik van Werkhoven; L. Moonen; Simon Horenblas

PURPOSEnWe assessed the prognostic significance of extranodal extension, defined as tumor extension through the lymph node capsule into the perinodal fibrous-adipose tissue, as well as several other risk factors in node positive penile cancer cases.nnnMATERIALS AND METHODSnWe analyzed prospectively collected data on a consecutive series of 156 chemotherapy naïve patients with proven lymph node involvement who underwent therapeutic regional lymphadenectomy. Postoperative external radiotherapy was indicated when histopathological analysis revealed more tumor than 1 intranodal metastasis. We estimated cancer specific survival using the Kaplan-Meier method. Multivariate analysis was done according to the Cox proportional hazards model of factors statistically significant on univariate analysis.nnnRESULTSnAdjuvant radiotherapy was done in 70 patients (45%). Median followup was 57.8 months. Overall 5-year cancer specific survival was 61%. Men with extranodal extension had significantly decreased 5-year cancer specific survival compared with men without it (42% vs 80%). Other prognostic variables on univariate analysis were bilateral metastatic involvement vs unilateral, 3 or greater unilateral metastatic inguinal nodes vs 2 or fewer, inguinal lymphadenectomy positive margin status vs negative status and pelvic lymph node involvement. Pathological T stage or differentiation grade were not significant predictors of outcome. On multivariate analysis extranodal extension and pelvic lymph node involvement remained associated with decreased cancer specific survival (HR 2.37 and 2.20, respectively).nnnCONCLUSIONSnMetastatic inguinal lymph node extranodal extension and pelvic lymph node involvement are independent predictive parameters of cancer specific survival in patients with pathologically node positive penile carcinoma despite surgery with postoperative radiotherapy.


Oral Oncology | 2015

Determinants of treatment waiting times for head and neck cancer in the Netherlands and their relation to survival

Michel C. van Harten; Frank Hoebers; Kenneth W. Kross; Erik van Werkhoven; Michiel W. M. van den Brekel; Boukje A. C. van Dijk

INTRODUCTIONnWaiting to start treatment has been shown to be associated with tumor progression and upstaging in head and neck squamous cell carcinomas (HNSCCs). This diminishes the chance of cure and might lead to unnecessary mortality. We investigated the association between waiting times and survival in the Netherlands and assessed which factors were associated to longer waiting times.nnnMETHODSnPatient (age, sex, socioeconomic status (SES), tumor (site, stage) and treatment (type, of institute of diagnosis/treatment) characteristics for patients with HNSCC who underwent treatment were extracted from the Netherlands Cancer Registry (NCR) for 2005-2011. Waiting time was defined as the number of days between histopathological diagnosis and start of treatment. Univariable and multivariable Cox regression was used to evaluate survival.nnnRESULTSnIn total, 13,140 patients were included, who had a median waiting time of 37days. Patients who were more likely to wait longer were men, patients with a low SES, oropharynx tumors, stage IV tumors, patients to be treated with radiotherapy or chemoradiation, and patients referred for treatment to a Head and Neck Oncology Center (HNOC) from another hospital. The 5-year overall survival was 58% for all patients. Our multivariable Cox regression model showed that longer waiting time, was significantly related to a higher hazard of dying (p<0.0001).nnnCONCLUSIONnThis is the first large population-based study showing that longer waiting time for surgery, radiotherapy or chemoradiation is a significant negative prognostic factor for HNSCC patients.


The Journal of Urology | 2014

Contemporary management of regional nodes in penile cancer-improvement of survival?

Rosa S. Djajadiningrat; Niels M. Graafland; Erik van Werkhoven; W. Meinhardt; Axel Bex; Henk G. van der Poel; Hester van Boven; Renato A. Valdés Olmos; Simon Horenblas

PURPOSEnThe management of regional nodes of penile squamous cell carcinoma has changed with time due to improved knowledge about diagnosis and treatment. To determine whether changes in the treatment of regional nodes have improved survival, we compared contemporary 5-year cancer specific survival of patients with squamous cell carcinoma of the penis with that of patients in previous cohorts.nnnMATERIALS AND METHODSnIn an observational cohort study of 1,000 patients treated during 56 years 944 were eligible for analysis. Tumors were staged according to the 2009 TNM classification, and patients were divided into 4 cohorts of 1956 to 1987, 1988 to 1993, 1994 to 2000 and 2001 to 2012, reflecting changes in clinical practice regarding regional nodes. Kaplan-Meier survival curves with the log rank test and Cox proportional hazards modeling were used to examine trends in 5-year cancer specific survival.nnnRESULTSnThe 5-year cancer specific survival of patients with cN0 disease treated between 2001 and 2012 was 92% compared to 89% (1994 to 2000), 78% (1988 to 1993) and 85% (1956 to 1987). The 5-year cancer specific survival improved significantly since 1994, the year dynamic sentinel node biopsy was introduced, at 91% (1994 to 2012) vs 82% (1956 to 1993) (p = 0.021). This conclusion still holds after adjustment for pathological T stage and grade of differentiation (HR 2.46, p = 0.01). Extranodal extension, number of tumor positive nodes and pelvic involvement in node positive (pN+) cases were associated with worse 5-year cancer specific survival.nnnCONCLUSIONSnDespite less surgery being performed on regional nodes, 5-year cancer specific survival has improved in patients with cN0 disease. The number of tumor positive nodes, extranodal extension and pelvic involvement were highly associated with worse cancer specific survival in patients with pN+ disease. In this group other treatment strategies are needed as no improvement was observed.


Radiotherapy and Oncology | 2011

Nomogram to predict ipsilateral breast relapse based on pathology review from the EORTC 22881-10882 boost versus no boost trial

Erik van Werkhoven; Guus Hart; Harm van Tinteren; Paula H.M. Elkhuizen; Laurence Collette; Philip Poortmans; Harry Bartelink

BACKGROUND AND PURPOSEnThe EORTC 22881-10882 trial showed that for patients treated with breast conserving therapy (BCT), a 16Gy boost dose significantly improved local control, but increased the risk of breast fibrosis. A model to estimate the risk of ipsilateral breast relapse (IBR) already exists, but now a model has been developed which takes boost treatment into account and is based on centrally reviewed pathology.nnnMATERIALS AND METHODSnA Cox model was developed based on central pathology review data and clinical data of 1603 patients from the EORTC 22881-10882 trial with a median follow-up of 11.5years. From a predefined set of variables, predictors with a maximal effect on 10-year IBR rate >4% were retained in the model. Bootstrap re-sampling was used to assess model calibration and discrimination. The results are presented in the form of a nomogram.nnnRESULTSnApart from young age and no boost, presence of DCIS adjacent to the invasive tumor was associated with increased risk of IBR (HR 1.96, p=0.001). Patients with high grade invasive tumors were younger than patients with low/intermediate grade (p<0.0001). The nomogram includes histologic grade, DCIS, tumor diameter, age, tamoxifen, chemotherapy, and boost with a concordance probability estimate of 0.68.nnnCONCLUSIONSnThe nomogram for predicting IBR 10years after BCT includes seven factors, with young age, presence of DCIS and boost treatment as the most dominant factors. The nomogram estimates IBR and confirms the importance of a boost dose. Combined with a model to predict fibrosis published previously, the nomogram presented here may assist in decision making for individual patients.


The Journal of Urology | 2015

Human papillomavirus prevalence in invasive penile cancer and association with clinical outcome.

Rosa S. Djajadiningrat; Ekaterina S. Jordanova; Bin K. Kroon; Erik van Werkhoven; Jeroen de Jong; Divera T.M. Pronk; Peter J.F. Snijders; Simon Horenblas; Daniëlle A.M. Heideman

PURPOSEnThe incidence of penile cancer is increasing, and is suggested to be explained by changes in sexual practice and increased exposure of men to sexually transmitted high risk human papillomavirus infection. In penile cancers from a Dutch population treated in 1963 to 2001 we found a high risk human papillomavirus prevalence of about 30%. In this study we assessed the prevalence of high risk human papillomavirus-DNA in a more recent, contemporary penile cancer cohort and its association with patient survival.nnnMATERIALS AND METHODSnHigh risk human papillomavirus-DNA presence was assessed by GP5+6+ polymerase chain reaction in 212 formalin fixed, paraffin embedded invasive penile tumor specimens of patients treated between 2001 and 2009. The 5-year disease specific survival was calculated using the Kaplan-Meier method with the log rank test and Cox regression.nnnRESULTSnHigh risk human papillomavirus-DNA was detected in a subset of penile cancer cases (25%, 95% CI 19-31). HPV16 was the predominant type, representing 79% (42 of 53) of all high risk human papillomavirus infections. The 5-year disease specific survival in the high risk human papillomavirus negative group and the high risk human papillomavirus positive group was 82% and 96%, respectively (log rank test p=0.016). Adjusted for stage, grade, lymphovascular invasion and age, human papillomavirus status was still prognostic for disease specific survival (p=0.030) with a hazard ratio of 0.2 (95% CI 0.1-0.9).nnnCONCLUSIONSnHigh risk human papillomavirus-DNA was observed in a quarter of penile cancer cases. No relevant increase in high risk human papillomavirus prevalence in recent decades was observed. The presence of high risk human papillomavirus-DNA in penile cancer confers a survival advantage.


JAMA Oncology | 2016

Angiotensin II-Receptor Inhibition With Candesartan to Prevent Trastuzumab-Related Cardiotoxic Effects in Patients With Early Breast Cancer : A Randomized Clinical Trial

Annelies H. Boekhout; Jourik A. Gietema; Bojana Milojkovic Kerklaan; Erik van Werkhoven; Renske Altena; Aafke Honkoop; Maartje Los; Willem M. Smit; Peter Nieboer; Carolien H. Smorenburg; Caroline M. Mandigers; Agnes J. van der Wouw; Lonneke Kessels; Annette W. G. van der Velden; P.B. Ottevanger; Tineke J. Smilde; Jaap de Boer; Dirk J. van Veldhuisen; Ido P. Kema; Elisabeth G.E. de Vries; Jan H. M. Schellens

IMPORTANCEnThis is the first randomized placebo-controlled evaluation of a medical intervention for the prevention of trastuzumab-related cardiotoxic effects.nnnOBJECTIVEnTo determine as the primary end point whether angiotensin II antagonist treatment with candesartan can prevent or ameliorate trastuzumab-related cardiotoxic effects, defined as a decline in left ventricular ejection fraction (LVEF) of more than 15% or a decrease below the absolute value 45%.nnnDESIGNnThis randomized, placebo-controlled clinical study was conducted between October 2007 and October 2011 in 19 hospitals in the Netherlands, enrolling 210 women with early breast cancer testing positive for human epidermal growth factor receptor 2 (HER2) who were being considered for adjuvant systemic treatment with anthracycline-containing chemotherapy followed by trastuzumab.nnnINTERVENTIONSnA total of 78 weeks of candesartan (32 mg/d) or placebo treatment; study treatment started at the same day as the first trastuzumab administration and continued until 26 weeks after completion of trastuzumab treatment.nnnMAIN OUTCOMES AND MEASURESnThe primary outcome was LVEF. Secondary end points included whether the N-terminal of the prohormone brain natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hs-TnT) can be used as surrogate markers and whether genetic variability in germline ERBB2 (formerly HER2 or HER2/neu) correlates with trastuzumab-related cardiotoxic effects.nnnRESULTSnA total of 206 participants were evaluable (mean age, 49 years; age range, 25-69 years) 103 in the candesartan group (mean age, 50 years; age range, 25-69 years) and 103 in the placebo group (mean age, 50 years; age range, 30-67 years). Of these, 36 manifested at least 1 of the 2 primary cardiac end points. There were 3.8% more cardiac events in the candesartan group than in the placebo group (95% CI, -7% to 15%; Pu2009=u2009.58): 20 events (19%) and 16 events (16%), respectively. The 2-year cumulative incidence of cardiac events was 0.28 (95% CI, 0.13-0.40) in the candesartan group and 0.16 (95% CI, 0.08-0.22) in the placebo group (Pu2009=u2009.56). Candesartan did not affect changes in NT-proBNP and hs-TnT values, and these biomarkers were not associated with significant changes in LVEF. The Ala1170Pro homozygous ERBB2 genotype was associated with a lower likelihood of the occurrence of a cardiac event compared with Pro/Prou2009+u2009Ala/Pro genotypes in multivariate analysis (odds ratio, 0.09; 95% CI, 0.02-0.45; Pu2009=u2009.003).nnnCONCLUSIONS AND RELEVANCEnThe findings do not support the hypothesis that concomitant use of candesartan protects against a decrease in left ventricular ejection fraction during or shortly after trastuzumab treatment in early breast cancer. The ERBB2 germline Ala1170Pro single nucleotide polymorphism may be used to identify patients who are at increased risk of trastuzumab-related cardiotoxic effects.nnnTRIAL REGISTRATIONnclinicaltrials.gov Identifier: NCT00459771.


The Journal of Urology | 2014

Penile sparing surgery for penile cancer-does it affect survival?

Rosa S. Djajadiningrat; Erik van Werkhoven; W. Meinhardt; Bas W.G. van Rhijn; Axel Bex; Henk G. van der Poel; Simon Horenblas

PURPOSEnManagement of squamous cell carcinoma of the penis changed in recent decades in favor of penile sparing surgery. We assessed whether penile sparing therapies were increasingly applied in our penile squamous cell carcinoma cohort with time and whether penile sparing affected 5-year cancer specific survival.nnnMATERIALS AND METHODSnWe reviewed the records of 1,000 patients treated between 1956 and 2012, of whom 859 with invasive tumors were eligible for analysis. Tumors were staged according to the 2009 TNM classification. Binary logistic regression was used to assess penile preservation vs amputation with time. Cancer specific survival was analyzed using the Kaplan-Meier method and multivariable Cox proportional hazards model. Competing risk analysis was done for local recurrence.nnnRESULTSnWith time significantly fewer penile amputations were performed. The 5-year cumulative incidence of local recurrence as the first event after penile preservation was 27% (95% CI 23-32) while after (partial) penectomy it was 3.8% (95% CI 2.3-6.2, Gray test p <0.0001). Patients treated with penile preservation showed no significant difference in survival compared to patients treated with (partial) amputation after adjusting for relevant covariables. Factors associated with cancer specific survival were pathological T stage, pathological N stage and lymphovascular invasion on multivariable analysis. In the penile preservation group local recurrence as a time dependent variable in a Cox model was not associated with cancer specific survival (HR 0.52, 95% CI 0.21-1.24, p = 0.13).nnnCONCLUSIONSnSignificantly more penile preservation therapies were performed in more recent years. Although patients treated with penile preservation experienced more local recurrences, 5-year cancer specific survival was not jeopardized.

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Simon Horenblas

Netherlands Cancer Institute

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Axel Bex

Netherlands Cancer Institute

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Henk G. van der Poel

Netherlands Cancer Institute

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Bas W.G. van Rhijn

Netherlands Cancer Institute

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Jan H. M. Schellens

Netherlands Cancer Institute

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Laura S. Mertens

Netherlands Cancer Institute

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Harry Bartelink

Netherlands Cancer Institute

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