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Featured researches published by Ronald M. van Dam.


Journal of Clinical Oncology | 2011

Wait-and-See Policy for Clinical Complete Responders After Chemoradiation for Rectal Cancer

Monique Maas; Regina G. H. Beets-Tan; Doenja M. J. Lambregts; Guido Lammering; Patty J. Nelemans; Sanne M. E. Engelen; Ronald M. van Dam; Rob L. Jansen; M. N. Sosef; Jeroen W. A. Leijtens; Karel W.E. Hulsewé; Jeroen Buijsen; Geerard L. Beets

PURPOSE Neoadjuvant chemoradiotherapy for rectal cancer can result in complete disappearance of tumor and involved nodes. In patients without residual tumor on imaging and endoscopy (clinical complete response [cCR]) a wait-and-see-policy (omission of surgery with follow-up) might be considered instead of surgery. The purpose of this prospective cohort study was to evaluate feasibility and safety of a wait-and-see policy with strict selection criteria and follow-up. PATIENTS AND METHODS Patients with a cCR after chemoradiotherapy were prospectively selected for the wait-and-see policy with magnetic resonance imaging (MRI) and endoscopy plus biopsies. Follow-up was performed 3 to 6 monthly and consisted of MRI, endoscopy, and computed tomography scans. A control group of patients with a pathologic complete response (pCR) after surgery was identified from a prospective cohort study. Functional outcome was measured with the Memorial Sloan-Kettering Cancer Center (MSKCC) bowel function questionnaire and Wexner incontinence score. Long-term outcome was estimated by using Kaplan-Meier curves. RESULTS Twenty-one patients with cCR were included in the wait-and-see policy group. Mean follow-up was 25 ± 19 months. One patient developed a local recurrence and had surgery as salvage treatment. The other 20 patients are alive without disease. The control group consisted of 20 patients with a pCR after surgery who had a mean follow-up of 35 ± 23 months. For these patients with a pCR, cumulative probabilities of 2-year disease-free survival and overall survival were 93% and 91%, respectively. CONCLUSION A wait-and-see policy with strict selection criteria, up-to-date imaging techniques, and follow-up is feasible and results in promising outcome at least as good as that of patients with a pCR after surgery. The proposed selection criteria and follow-up could form the basis for future randomized studies.


Annals of Surgery | 2016

Recommendations for laparoscopic liver resection: a report from the second international consensus conference held in Morioka.

Go Wakabayashi; Daniel Cherqui; David A. Geller; Joseph E. Buell; Hironori Kaneko; Ho Seong Han; Horacio Asbun; Nicholas O'Rourke; Minoru Tanabe; Alan J. Koffron; Allan Tsung; Olivier Soubrane; Marcel Autran Cesar Machado; Brice Gayet; Roberto Troisi; Patrick Pessaux; Ronald M. van Dam; Olivier Scatton; Mohammad Abu Hilal; Giulio Belli; Choon Hyuck David Kwon; Bjørn Edwin; Gi Hong Choi; Luca Aldrighetti; Xiujun Cai; Sean Clemy; Kuo-Hsin Chen; Michael R. Schoen; Atsushi Sugioka; Chung-Ngai Tang

OBJECTIVE This review aims to assess the impact of implementing dedicated emergency surgical services, in particular acute care surgery, on clinical outcomes. BACKGROUND The optimal model for delivering high-quality emergency surgical care remains unknown. Acute Care Surgery (ACS) is a health care model combining emergency general surgery, trauma, and critical care. It has been adopted across the United States in the management of surgical emergencies. METHOD A systematic review was performed after PRISMA recommendations using the MEDLINE, Embase, and Psych-Info databases. Studies assessing different care models and institutional factors affecting the delivery of emergency general surgery were included. RESULTS Twenty-seven studies comprising 744,238 patients were included in this review. In studies comparing ACS with traditional practice, mortality and morbidity were improved. Moreover, time to senior review, delays to operating theater, and financial expenditure were often reduced. The elements of ACS models varied but included senior clinicians present onsite during office hours and dedicated to emergency care while on-call. Referrals were made to specialist centers with primary surgical assessments taking place on surgical admissions units rather than in the emergency department. Twenty-four-hour access to dedicated emergency operating rooms was also described. CONCLUSIONS ACS models as well as centralized units and hospitals with dedicated emergency operating rooms, access to radiology and intensive care facilities (ITU) are all factors associated with improved clinical and financial outcomes in the delivery of emergency general surgery. There is, however, no consensus on the elements that constitute an ideal ACS model and how it can be implemented into current surgical practice.


BMC Surgery | 2006

Perioperative strategy in colonic surgery; LAparoscopy and/or FAst track multimodal management versus standard care (LAFA trial)

Jan Wind; Jan Hofland; Benedikt Preckel; Markus W. Hollmann; Patrick M. Bossuyt; Dirk J. Gouma; Mark I. van Berge Henegouwen; Jan Willem Fuhring; Cornelis H.C. Dejong; Ronald M. van Dam; Miguel A. Cuesta; Astrid Noordhuis; Dick de Jong; Edith van Zalingen; Alexander Engel; T. Hauwy Goei; I. Erica de Stoppelaar; Willem F. van Tets; Bart A. van Wagensveld; Annemiek Swart; Maarten J. L. J. van den Elsen; Michael F. Gerhards; Laurens T. de Wit; Muriel A. M. Siepel; Anna A. W. van Geloven; Jan-Willem Juttmann; Wilfred Clevers; Willem A. Bemelman

BackgroundRecent developments in large bowel surgery are the introduction of laparoscopic surgery and the implementation of multimodal fast track recovery programs. Both focus on a faster recovery and shorter hospital stay.The randomized controlled multicenter LAFA-trial (LAparoscopy and/or FAst track multimodal management versus standard care) was conceived to determine whether laparoscopic surgery, fast track perioperative care or a combination of both is to be preferred over open surgery with standard care in patients having segmental colectomy for malignant disease.Methods/designThe LAFA-trial is a double blinded, multicenter trial with a 2 × 2 balanced factorial design. Patients eligible for segmental colectomy for malignant colorectal disease i.e. right and left colectomy and anterior resection will be randomized to either open or laparoscopic colectomy, and to either standard care or the fast track program. This factorial design produces four treatment groups; open colectomy with standard care (a), open colectomy with fast track program (b), laparoscopic colectomy with standard care (c), and laparoscopic surgery with fast track program (d). Primary outcome parameter is postoperative hospital length of stay including readmission within 30 days. Secondary outcome parameters are quality of life two and four weeks after surgery, overall hospital costs, morbidity, patient satisfaction and readmission rate.Based on a mean postoperative hospital stay of 9 +/- 2.5 days a group size of 400 patients (100 each arm) can reliably detect a minimum difference of 1 day between the four arms (alfa = 0.95, beta = 0.8). With 100 patients in each arm a difference of 10% in subscales of the Short Form 36 (SF-36) questionnaire and social functioning can be detected.DiscussionThe LAFA-trial is a randomized controlled multicenter trial that will provide evidence on the merits of fast track perioperative care and laparoscopic colorectal surgery in patients having segmental colectomy for malignant disease.


American Journal of Pathology | 2010

Human Intestinal Ischemia-Reperfusion–Induced Inflammation Characterized : Experiences from a New Translational Model

Joep Grootjans; Kaatje Lenaerts; Joep P. M. Derikx; Robert A. Matthijsen; Adriaan P. de Bruïne; Annemarie A. van Bijnen; Ronald M. van Dam; Cornelis H.C. Dejong; Wim A. Buurman

Human intestinal ischemia-reperfusion (IR) is a frequent phenomenon carrying high morbidity and mortality. Although intestinal IR-induced inflammation has been studied extensively in animal models, human intestinal IR induced inflammatory responses remain to be characterized. Using a newly developed human intestinal IR model, we show that human small intestinal ischemia results in massive leakage of intracellular components from ischemically damaged cells, as indicated by increased arteriovenous concentration differences of intestinal fatty acid binding protein and soluble cytokeratin 18. IR-induced intestinal barrier integrity loss resulted in free exposure of the gut basal membrane (collagen IV staining) to intraluminal contents, which was accompanied by increased arteriovenous concentration differences of endotoxin. Western blot for complement activation product C3c and immunohistochemistry for activated C3 revealed complement activation after IR. In addition, intestinal IR resulted in enhanced tissue mRNA expression of IL-6, IL-8, and TNF-alpha, which was accompanied by IL-6 and IL-8 release into the circulation. Expression of intercellular adhesion molecule-1 was markedly increased during reperfusion, facilitating influx of neutrophils into IR-damaged villus tips. In conclusion, this study for the first time shows the sequelae of human intestinal IR-induced inflammation, which is characterized by complement activation, production and release of cytokines into the circulation, endothelial activation, and neutrophil influx into IR-damaged tissue.


PLOS ONE | 2008

Rapid Reversal of Human Intestinal Ischemia-Reperfusion Induced Damage by Shedding of Injured Enterocytes and Reepithelialisation

Joep P. M. Derikx; Robert A. Matthijsen; Adriaan P. de Bruïne; Annemarie A. van Bijnen; Erik Heineman; Ronald M. van Dam; Cornelis H.C. Dejong; Wim A. Buurman

Background Intestinal ischemia-reperfusion (IR) is a phenomenon related to physiological conditions (e.g. exercise, stress) and to pathophysiological events (e.g. acute mesenteric ischemia, aortic surgery). Although intestinal IR has been studied extensively in animals, results remain inconclusive and data on human intestinal IR are scarce. Therefore, an experimental harmless model for human intestinal IR was developed, enabling us to clarify the sequelae of human intestinal IR for the first time. Methods and Findings In 30 patients undergoing pancreatico-duodenectomy we took advantage of the fact that in this procedure a variable length of jejunum is removed. Isolated jejunum (5 cm) was subjected to 30 minutes ischemia followed by reperfusion. Intestinal Fatty Acid Binding Protein (I-FABP) arteriovenous concentration differences across the bowel segment were measured before and after ischemia to assess epithelial cell damage. Tissue sections were collected after ischemia and at 25, 60 and 120 minutes reperfusion and stained with H&E, and for I-FABP and the apoptosis marker M30. Bonferronis test was used to compare I-FABP differences. Mean (SEM) arteriovenous concentration gradients of I-FABP across the jejunum revealed rapidly developing epithelial cell damage. I-FABP release significantly increased from 290 (46) pg/ml before ischemia towards 3,997 (554) pg/ml immediately after ischemia (p<0.001) and declined gradually to 1,143 (237) pg/ml within 1 hour reperfusion (p<0.001). Directly after ischemia the intestinal epithelial lining was microscopically normal, while subepithelial spaces appeared at the villus tip. However, after 25 minutes reperfusion, enterocyte M30 immunostaining was observed at the villus tip accompanied by shedding of mature enterocytes into the lumen and loss of I-FABP staining. Interestingly, within 60 minutes reperfusion the epithelial barrier resealed, while debris of apoptotic, shedded epithelial cells was observed in the lumen. At the same time, M30 immunoreactivity was absent in intact epithelial lining. Conclusions This is the first human study to clarify intestinal IR induced cell damage and repair and its direct consequences. It reveals a unique, endogenous clearing mechanism for injured enterocytes: rapid detachment of damaged apoptotic enterocytes into the lumen. This process is followed by repair of the epithelial continuity within an hour, resulting in a normal epithelial lining.


Gastroenterology | 2011

Level of Activation of the Unfolded Protein Response Correlates With Paneth Cell Apoptosis in Human Small Intestine Exposed to Ischemia/Reperfusion

Joep Grootjans; Caroline M. Hodin; Jacco J. de Haan; Joep P. M. Derikx; Fons Verheyen; Ronald M. van Dam; Cornelis H.C. Dejong; Wim A. Buurman; Kaatje Lenaerts

BACKGROUND & AIMS In the intestine, Paneth cells participate in the innate immune response. Their highly secretory function makes them susceptible to environmental conditions that cause endoplasmic reticulum (ER) stress. We investigated whether intestinal ischemia/reperfusion (I/R) induces ER stress, thereby activating the unfolded protein response (UPR), and whether excessive UPR activation affects Paneth cells. In addition, we investigated the consequences of Paneth cell compromise during physical barrier damage. METHODS Jejunal I/R was studied using a human experimental model (n = 30 patients). Activation of the UPR was assessed using immunofluorescence for binding protein and quantitative polymerase chain reaction analyses for C/EBP homologous protein (CHOP), growth arrest and DNA-damage inducible protein 34 (GADD34), and X-box binding protein 1 (XBP1) splicing. Paneth cell apoptosis was assessed by double staining for lysozyme and M30. Male Sprague-Dawley rats underwent either intestinal I/R to investigate UPR activation and Paneth cell apoptosis, or hemorrhagic shock with or without intraperitoneal administration of dithizone, to study consequences of Paneth cell compromise during physical intestinal damage. In these animals, bacterial translocation and circulating tumor necrosis factor-α and interleukin-6 levels were assessed. RESULTS In jejunum samples from humans and rats, I/R activated the UPR and resulted in Paneth cell apoptosis. Apoptotic Paneth cells showed signs of ER stress, and Paneth cell apoptosis correlated with the extent of ER stress. Apoptotic Paneth cells were shed into the crypt lumen, significantly lowering their numbers. In rats, Paneth cell compromise increased bacterial translocation and inflammation during physical intestinal damage. CONCLUSIONS ER stress-induced Paneth cell apoptosis contributes to intestinal I/R-induced bacterial translocation and systemic inflammation.


Hpb | 2013

A systematic review of outcomes in patients undergoing liver surgery in an enhanced recovery after surgery pathways

M.M.E. Coolsen; Edgar M. Wong-Lun-Hing; Ronald M. van Dam; Aart A. van der Wilt; Karem Slim; Kristoffer Lassen; Cornelis H.C. Dejong

OBJECTIVES Enhanced recovery after surgery (ERAS) or fast-track protocols have been implemented in different fields of surgery to attenuate the surgical stress response and accelerate recovery. The objective of this study was to systematically review the literature on outcomes of ERAS protocols applied in liver surgery. METHODS The MEDLINE, EMBASE, PubMed and Cochrane Library databases were searched for randomized controlled trials (RCTs), case-control studies and case series published between January 1966 and October 2011 comparing adult patients undergoing elective liver surgery in an ERAS programme with those treated in a conventional manner. The primary outcome measure was hospital length of stay (LoS). Secondary outcome measures were time to functional recovery, and complication, readmission and mortality rates. RESULTS A total of 307 articles were found, six of which were included in the review. These comprised two RCTs, three case-control studies and one retrospective case series. Median LoS ranged from 4 days in an ERAS group to 11 days in a control group. Morbidity, mortality and readmission rates did not differ significantly between the groups. Only two studies assessed time to functional recovery. Functional recovery in these studies was reached 2 days before discharge. CONCLUSIONS This systematic review suggests that ERAS protocols can be successfully implemented in liver surgery. Length of stay is reduced without compromising morbidity, mortality or readmission rates.


Hpb | 2009

The effect of a multimodal fast-track programme on outcomes in laparoscopic liver surgery: a multicentre pilot study

Jan H.M.B. Stoot; Ronald M. van Dam; Olivier R. Busch; Richard van Hillegersberg; Marieke T. de Boer; Steven W.M. Olde Damink; Marc H.A. Bemelmans; Cornelis H.C. Dejong

OBJECTIVES This study was conducted to evaluate the added value of an enhanced recovery after surgery (ERAS) programme in laparoscopic liver resections for solid tumours. METHODS Patients undergoing laparoscopic liver resection between July 2005 and July 2008 were included. Indications for resections included presumed benign and malignant liver lesions. Primary outcome was total length of hospital stay (LOS). Secondary outcomes were functional recovery, complications, conversions, blood loss and duration of operation. RESULTS Thirteen patients were treated by laparoscopic liver resections in the ERAS programme in one centre (group 1). Their outcomes were compared with outcomes of 13 laparoscopic procedures performed either before the introduction of the ERAS programme during 2003-2005 in the same centre or during the same period in other centres using traditional care (group 2). Median total LOS was 5.0 days (range 3-10 days) in group 1 and 7.0 days (3-12 days) in group 2. This difference was not statistically significant. Functional recovery occurred 2 days earlier in group 1 (median 3.0 days [range 1-7 days] vs. median 5.0 days [range 2-8 days]; P < 0.044). There were no significant differences in complications, conversions or duration of operation. Blood loss was significantly less in the ERAS group (median 50 ml [range 50-200 ml] vs. median 250 ml [range 50-800 ml]; P < 0.002). CONCLUSIONS This exploratory, multicentre, fast-track laparoscopic liver resection study is the first such study conducted. Although small, the study suggests that a multimodal enhanced recovery programme in laparoscopic liver surgery is feasible, safe and may lead to accelerated functional recovery and reductions in LOS.


Trials | 2012

Open versus laparoscopic left lateral hepatic sectionectomy within an enhanced recovery ERAS® programme (ORANGE II – Trial): study protocol for a randomised controlled trial

Ronald M. van Dam; Edgar M. Wong-Lun-Hing; Gerard J P van Breukelen; Jan H.M.B. Stoot; Joost R. van der Vorst; Marc H.A. Bemelmans; Steven W. M. Olde Damink; Kristoffer Lassen; Cornelis H.C. Dejong

BackgroundThe use of lLaparoscopic liver resection in terms of time to functional recovery, length of hospital stay (LOS), long-term abdominal wall hernias, costs and quality of life (QOL) has never been studied in a randomised controlled trial. Therefore, this is the subject of the international multicentre randomised controlled ORANGE II trial.MethodsPatients eligible for left lateral sectionectomy (LLS) of the liver will be recruited and randomised at the outpatient clinic. All randomised patients will undergo surgery in the setting of an ERAS programme. The experimental design produces two randomised arms (open and laparoscopic LLS) and a prospective registry. The prospective registry will be based on patients that cannot be randomised because of the explicit treatment preference of the patient or surgeon, or because of ineligibility (not meeting the in- and exclusion criteria) for randomisation in this trial. Therefore, all non-randomised patients undergoing LLS will be approached to participate in the prospective registry, thereby allowing acquisition of an uninterrupted prospective series of patients. The primary endpoint of the ORANGE II trial is time to functional recovery. Secondary endpoints are postoperative LOS, percentage readmission, (liver-specific) morbidity, QOL, body image and cosmetic result, hospital and societal costs over 1 year, and long-term incidence of incisional hernias. It will be assumed that in patients undergoing laparoscopic LLS, length of hospital stay can be reduced by two days. A sample size of 55 patients in each randomisation arm has been calculated to detect a 2-day reduction in LOS (90% power and α = 0.05 (two-tailed)).The ORANGE II trial is a multicenter randomised controlled trial that will provide evidence on the merits of laparoscopic surgery in patients undergoing LLS within an enhanced recovery ERAS programme.Trial registrationClinicalTrials.gov NCT00874224.


Archives of Surgery | 2012

Clinical outcome in relation to timing of surgery in chronic pancreatitis: a nomogram to predict pain relief

Usama Ahmed Ali; Vincent B. Nieuwenhuijs; Casper H.J. van Eijck; Hein G. Gooszen; Ronald M. van Dam; Olivier R. Busch; Marcel G. W. Dijkgraaf; Femke A. Mauritz; Sjoerd Jens; Jay Mast; Harry van Goor; Marja A. Boermeester

OBJECTIVE To evaluate the effect of timing of surgery on the long-term clinical outcome of surgery in chronic pancreatitis (CP). DESIGN Cohort study with long-term follow-up. SETTING Five specialized academic centers. PATIENTS Patients with CP treated surgically for pain. INTERVENTIONS Pancreatic resection and drainage procedures for pain relief. MAIN OUTCOME MEASURES Pain relief (pain visual analogue score ≤4), pancreatic function, and quality of life. RESULTS We included 266 patients with median follow-up of 62 months (interquartile range, 31-112). Results were presented as odds ratios (ORs)with 95% confidence intervals after correction for bias using bootstrap-corrected analysis. Pain relief was achieved in 149 patients (58%). Surgery within 3 years of symptoms was independently associated with more pain relief (OR, 1.8; 95% CI, 1.0-3.4; P = .03) and less endocrine pancreatic insufficiency (OR, 0.57; 95% CI, 0.33-0.96; P = .04). More pain relief was also observed in patients not taking opioids preoperatively (OR, 2.1; 95% CI, 1.2-4.0; P = .006) and who had 5 or fewer endoscopic treatments prior to surgery (OR, 2.5; 95% CI, 1.1-6.3; P = .04). The probability of achieving pain relief varied between 23% and 75%, depending on these risk factors. CONCLUSIONS The timing of surgery is an important risk factor for clinical outcome in CP. Surgery may need to be considered at an earlier phase than it is now, preferably within 3 years of symptomatic CP. Likelihood of postoperative pain relief can be calculated on an individual basis using the presented nomogram.

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Bert A. Bonsing

Leiden University Medical Center

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Erwin van der Harst

Erasmus University Rotterdam

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