Bert Bonsing

Dr. Bert Bonsing

orcid

Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
10 April 2022 in Journal of Clinical Oncology
Verified
Journal Article
Closed access
EVEva Versteijne
Eva Versteijne
JDJacob L. van Dam
Jacob L. van Dam
MSMustafa Suker
Mustafa Suker
QJQuisette P. Janssen
Quisette P. Janssen
KGKarin Groothuis
Karin Groothuis
FGfor the Dutch Pancreatic Cancer Group
for the Dutch Pancreatic Cancer Group
PURPOSE: The benefit of neoadjuvant chemoradiotherapy in resectable and borderline resectable pancreatic cancer remains controversial. Initial results of the PREOPANC trial failed to demonstrate a statistically significant overall survival (OS) benefit. The long-term results are reported. METHODS: In this multicenter, phase III trial, patients with resectable and borderline resectable pancreatic cancer were randomly assigned (1:1) to neoadjuvant chemoradiotherapy or upfront surgery in 16 Dutch centers. Neoadjuvant chemoradiotherapy consisted of three cycles of gemcitabine combined with 36 Gy radiotherapy in 15 fractions during the second cycle. After restaging, patients underwent surgery followed by four cycles of adjuvant gemcitabine. Patients in the upfront surgery group underwent surgery followed by six cycles of adjuvant gemcitabine. The primary outcome was OS by intention-to-treat. No safety data were collected beyond the initial report of the trial. RESULTS: Between April 24, 2013, and July 25, 2017, 246 eligible patients were randomly assigned to neoadjuvant chemoradiotherapy (n = 119) and upfront surgery (n = 127). At a median follow-up of 59 months, the OS was better in the neoadjuvant chemoradiotherapy group than in the upfront surgery group (hazard ratio, 0.73; 95% CI, 0.56 to 0.96; P = .025). Although the difference in median survival was only 1.4 months (15.7 months v 14.3 months), the 5-year OS rate was 20.5% (95% CI, 14.2 to 29.8) with neoadjuvant chemoradiotherapy and 6.5% (95% CI, 3.1 to 13.7) with upfront surgery. The effect of neoadjuvant chemoradiotherapy was consistent across the prespecified subgroups, including resectable and borderline resectable pancreatic cancer. CONCLUSION: Neoadjuvant gemcitabine-based chemoradiotherapy followed by surgery and adjuvant gemcitabine improves OS compared with upfront surgery and adjuvant gemcitabine in resectable and borderline resectable pancreatic cancer.

9 March 2016 in Trials
Verified
Journal Article
Open access
PDF file
F(for the Dutch Pancreatic Cancer Group (DPCG)
for the Dutch Pancreatic Cancer Group (DPCG)
EVEva Versteijne
Eva Versteijne
Casper Van EijckCasper Van Eijck
Casper Van Eijck
CPCornelis J. A. Punt
Cornelis J. A. Punt
MSMustafa Suker
Mustafa Suker
GTGeertjan van Tienhoven
Geertjan van Tienhoven
Pancreatic cancer is the fourth largest cause of cancer death in the United States and Europe with over 100,000 deaths per year in Europe alone. The overall 5-year survival ranges from 2–7 % and has hardly improved over the last two decades. Approximately 15 % of all patients have resectable disease at diagnosis, and of those, only a subgroup has a resectable tumour at surgical exploration. Data from cohort studies have suggested that outcome can be improved by preoperative radiochemotherapy, but data from well-designed randomized studies are lacking. Our PREOPANC phase III trial aims to test the hypothesis that median overall survival of patients with resectable or borderline resectable pancreatic cancer can be improved with preoperative radiochemotherapy. The PREOPANC trial is a randomized, controlled, multicentric superiority trial, initiated by the Dutch Pancreatic Cancer Group. Patients with (borderline) resectable pancreatic cancer are randomized to A: direct explorative laparotomy or B: after negative diagnostic laparoscopy, preoperative radiochemotherapy, followed by explorative laparotomy. A hypofractionated radiation scheme of 15 fractions of 2.4 gray (Gy) is combined with a course of gemcitabine, 1,000 mg/m2/dose on days 1, 8 and 15, preceded and followed by a modified course of gemcitabine. The target volumes of radiation are delineated on a 4D CT scan, where at least 95 % of the prescribed dose of 36 Gy in 15 fractions should cover 98 % of the planning target volume. Standard adjuvant chemotherapy is administered in both treatment arms after resection (six cycles in arm A and four in arm B). In total, 244 patients will be randomized in 17 hospitals in the Netherlands. The primary endpoint is overall survival by intention to treat. Secondary endpoints are (R0) resection rate, disease-free survival, time to locoregional recurrence or distant metastases and perioperative complications. Secondary endpoints for the experimental arm are toxicity and radiologic and pathologic response. The PREOPANC trial is designed to investigate whether preoperative radiochemotherapy improves overall survival by means of increased (R0) resection rates in patients with resectable or borderline resectable pancreatic cancer. Trial open for accrual: 3 April 2013 The Netherlands National Trial Register – NTR3709 (8 November 2012) EU Clinical Trials Register – 2012-003181-40 (11 December 2012)

1 October 2022 in Journal of Clinical Oncology
Verified
Journal Article
Closed access
DKDerk C.F. Klatte
Derk C.F. Klatte
BBBas Boekestijn
Bas Boekestijn
MWMartin N.J.M. Wasser
Martin N.J.M. Wasser
SSShirin Feshtali Shahbazi
Shirin Feshtali Shahbazi
IIIsaura S. Ibrahim
Isaura S. Ibrahim
MLMonique E. van Leerdam
Monique E. van Leerdam
PURPOSE: Pancreatic cancer surveillance in high-risk individuals may lead to detection of pancreatic ductal adenocarcinoma (PDAC) at an earlier stage and with improved survival. This study evaluated the yield and outcomes of 20 years of prospective surveillance in a large cohort of individuals with germline pathogenic variants (PVs) in CDKN2A. METHODS: Prospectively collected data were analyzed from individuals participating in pancreatic cancer surveillance. Surveillance consisted of annual magnetic resonance imaging with magnetic resonance cholangiopancreatography and optional endoscopic ultrasound. RESULTS: Three hundred forty-seven germline PV carriers participated in surveillance and were followed for a median of 5.6 (interquartile range 2.3-9.9) years. A total of 36 cases of PDAC were diagnosed in 31 (8.9%) patients at a median age of 60.4 (interquartile range 51.3-64.1) years. The cumulative incidence of primary PDAC was 20.7% by age 70 years. Five carriers (5 of 31; 16.1%) were diagnosed with a second primary PDAC. Thirty (83.3%) of 36 PDACs were considered resectable at the time of imaging. Twelve cases (12 of 36; 33.3%) presented with stage I disease. The median survival after diagnosis of primary PDAC was 26.8 months, and the 5-year survival rate was 32.4% (95% CI, 19.1 to 54.8). Individuals with primary PDAC who underwent resection (22 of 31; 71.0%) had an overall 5-year survival rate of 44.1% (95% CI, 27.2 to 71.3). Nine (2.6%; 9 of 347) individuals underwent surgery for a suspected malignant lesion, which proved to not be PDAC, and this included five lesions with low-grade dysplasia. CONCLUSION: This long-term surveillance study demonstrates a high incidence of PDAC in carriers of a PV in CDKN2A. This provides evidence that surveillance in such a high-risk population leads to detection of early-stage PDAC with improved resectability and survival.

8 June 2023 in Annals of Surgery
Verified
Journal Article
Open access
JMJ. Sven D. Mieog
J. Sven D. Mieog
BBBert Bonsing
Bert Bonsing
FGfor the Dutch Pancreatic Cancer Group
for the Dutch Pancreatic Cancer Group
Objective: To assess the feasibility, proficiency, and mastery learning curves for robotic pancreatoduodenectomy (RPD) in “second-generation” RPD centers following a multicenter training program adhering to the IDEAL framework. Background: The long learning curves for RPD reported from “pioneering” expert centers may discourage centers interested in starting an RPD program. However, the feasibility, proficiency, and mastery learning curves may be shorter in “second-generation” centers that participated in dedicated RPD training programs, although data are lacking. We report on the learning curves for RPD in “second-generation” centers trained in a dedicated nationwide program. Methods: Post hoc analysis of all consecutive patients undergoing RPD in 7 centers that participated in the LAELAPS-3 training program, each with a minimum annual volume of 50 pancreatoduodenectomies, using the mandatory Dutch Pancreatic Cancer Audit (March 2016–December 2021). Cumulative sum analysis determined cutoffs for the 3 learning curves: operative time for the feasibility (1) risk-adjusted major complication (Clavien-Dindo grade ≥III) for the proficiency, (2) and textbook outcome for the mastery, (3) learning curve. Outcomes before and after the cutoffs were compared for the proficiency and mastery learning curves. A survey was used to assess changes in practice and the most valued “lessons learned.” Results: Overall, 635 RPD were performed by 17 trained surgeons, with a conversion rate of 6.6% (n=42). The median annual volume of RPD per center was 22.5±6.8. From 2016 to 2021, the nationwide annual use of RPD increased from 0% to 23% whereas the use of laparoscopic pancreatoduodenectomy decreased from 15% to 0%. The rate of major complications was 36.9% (n=234), surgical site infection 6.3% (n=40), postoperative pancreatic fistula (grade B/C) 26.9% (n=171), and 30-day/in-hospital mortality 3.5% (n=22). Cutoffs for the feasibility, proficiency, and mastery learning curves were reached at 15, 62, and 84 RPD. Major morbidity and 30-day/in-hospital mortality did not differ significantly before and after the cutoffs for the proficiency and mastery learning curves. Previous experience in laparoscopic pancreatoduodenectomy shortened the feasibility (−12 RPDs, −44%), proficiency (−32 RPDs, −34%), and mastery phase learning curve (−34 RPDs, −23%), but did not improve clinical outcome. Conclusions: The feasibility, proficiency, and mastery learning curves for RPD at 15, 62, and 84 procedures in “second-generation” centers after a multicenter training program were considerably shorter than previously reported from “pioneering” expert centers. The learning curve cutoffs and prior laparoscopic experience did not impact major morbidity and mortality. These findings demonstrate the safety and value of a nationwide training program for RPD in centers with sufficient volume.

12 March 2007 in BMC Surgery
Verified
Journal Article
Open access
PDF file
NGNiels A van der Gaag
Niels A van der Gaag
SCSteve Mm de Castro
Steve Mm de Castro
ERErik Aj Rauws
Erik Aj Rauws
MBMarco J Bruno
Marco J Bruno
Casper Van EijckCasper Van Eijck
Casper Van Eijck
DGDirk J Gouma
Dirk J Gouma
Surgery in patients with obstructive jaundice caused by a periampullary (pancreas, papilla, distal bile duct) tumor is associated with a higher risk of postoperative complications than in non-jaundiced patients. Preoperative biliary drainage was introduced in an attempt to improve the general condition and thus reduce postoperative morbidity and mortality. Early studies showed a reduction in morbidity. However, more recently the focus has shifted towards the negative effects of drainage, such as an increase of infectious complications. Whether biliary drainage should always be performed in jaundiced patients remains controversial. The randomized controlled multicenter DROP-trial (DRainage vs. Operation) was conceived to compare the outcome of a 'preoperative biliary drainage strategy' (standard strategy) with that of an 'early-surgery' strategy, with respect to the incidence of severe complications (primary-outcome measure), hospital stay, number of invasive diagnostic tests, costs, and quality of life.

11 June 2010 in BMC Medical Genetics
Verified
Journal Article
Open access
PDF file
FHFrederik J Hes
Frederik J Hes
MWMarjan M Weiss
Marjan M Weiss
SWSanne A Woortman
Sanne A Woortman
Noel de MirandaNoel de Miranda
Noel de Miranda
PBPatrick A van Bunderen
Patrick A van Bunderen
ECEleonora Pm Corssmit
Eleonora Pm Corssmit
Germline mutations of the succinate dehydrogenase subunit B gene (SDHB) predispose carriers for paragangliomas, and current estimates of the chance of mutation carriers actually developing tumors (penetrance) are high. We evaluate the phenotype and penetrance of a germline SDHB mutation in a large and clinically well-characterized paraganglioma family.