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Featured researches published by Koen Kessels.


Endoscopy | 2013

Reassessment of the predictive value of the Forrest classification for peptic ulcer rebleeding and mortality: can classification be simplified?

Nicolette L. de Groot; Martijn G. van Oijen; Koen Kessels; Maarten Hemmink; Bas L. Weusten; Robin Timmer; Wouter L. Hazen; Niels van Lelyveld; Reinoud Vermeijden; Wouter L. Curvers; Bert C. Baak; Robert Verburg; Joukje H. Bosman; Laetitia R. H. de Wijkerslooth; Janne de Rooij; Niels G. Venneman; Marieke Pennings; Koen van Hee; Bob C. H. Scheffer; Rachel L. van Eijk; Ruby Meiland; Peter D. Siersema; A. J. Bredenoord

BACKGROUND AND STUDY AIMS This study aimed to reassess whether the Forrest classification is still useful for the prediction of rebleeding and mortality in peptic ulcer bleedings and, based on this, whether the classification could be simplified. PATIENTS AND METHODS Prospective registry data on peptic ulcer bleedings were collected and categorized according to the Forrest classification. The primary outcomes were 30-day rebleeding and all-cause mortality rates. Receiver operating characteristic curves were used to test whether simplification of the Forrest classification into high risk (Forrest Ia), increased risk (Forrest Ib-IIc), and low risk (Forrest III) classes could be an alternative to the original classification. RESULTS In total, 397 patients were included, with 18 bleedings (4.5%) being classified as Forrest Ia, 73 (18.4%) as Forrest Ib, 86 (21.7%) as Forrest IIa, 32 (8.1%) as Forrest IIb, 59 (14.9%) as Forrest IIc, and 129 (32.5%) as Forrest III. Rebleeding occurred in 74 patients (18.6%). Rebleeding rates were highest in Forrest Ia peptic ulcers (59%). The odds ratios for rebleeding among Forrest Ib-IIc ulcers were similar. In subgroup analysis, predicting rebleeding using the Forrest classification was more reliable for gastric ulcers than for duodenal ulcers. The simplified Forrest classification had similar test characteristics to the original Forrest classification. CONCLUSION The Forrest classification still has predictive value for rebleeding of peptic ulcers, especially for gastric ulcers; however, it does not predict mortality. Based on these results, a simplified Forrest classification is proposed. However, further studies are needed to validate these findings.


United European gastroenterology journal | 2014

Prediction scores or gastroenterologists' Gut Feeling for triaging patients that present with acute upper gastrointestinal bleeding

N. L. de Groot; Mgh van Oijen; Koen Kessels; M Hemmink; Blam Weusten; Robin Timmer; Wouter L. Hazen; N van Lelyveld; J.R. Vermeijden; Wouter L. Curvers; Lc Baak; Robert Verburg; Jh Bosman; Lrh de Wijkerslooth; J de Rooij; Niels G. Venneman; M Pennings; K van Hee; Rch Scheffer; Rl van Eijk; R Meiland; Peter D. Siersema; A. J. Bredenoord

Introduction Several prediction scores for triaging patients with upper gastrointestinal (GI) bleeding have been developed, yet these scores have never been compared to the current gold standard, which is the clinical evaluation by a gastroenterologist. The aim of this study was to assess the added value of prediction scores to gastroenterologists’ Gut Feeling in patients with a suspected upper GI bleeding. Methods We prospectively evaluated Gut Feeling of senior gastroenterologists and asked them to estimate: (1) the risk that a clinical intervention is needed; (2) the risk of rebleeding; and (3) the risk of mortality in patients presenting with suspected upper GI bleeding, subdivided into low, medium, or high risk. The predictive value of the gastroenterologists’ Gut Feeling was compared to the Blatchford and Rockall scores for various outcomes. Results We included 974 patients, of which 667 patients (68.8%) underwent a clinical intervention. During the 30-day follow up, 140 patients (14.4%) developed recurrent bleeding and 44 patients (4.5%) died. Gut Feeling was independently associated with all studied outcomes, except for the predicted mortality after endoscopy. Predictive power, based on the AUC of the Blatchford and Rockall prediction scores, was higher than the Gut Feeling of the gastroenterologists. However, combining both the Blatchford and Rockall scores and the Gut Feeling yielded the highest predictive power for the need of an intervention (AUC 0.88), rebleeding (AUC 0.73), and mortality (AUC 0.71 predicted before and 0.77 predicted after endoscopy, respectively). Conclusions Gut Feeling is an independent predictor for the need of a clinical intervention, rebleeding, and mortality in patients presenting with upper GI bleeding; however, the Blatchford and Rockall scores are stronger predictors for these outcomes. Combining Gut Feeling with the Blatchford and Rockall scores resulted in the most optimal prediction.


The American Journal of Gastroenterology | 2017

Risk for Incomplete Resection after Macroscopic Radical Endoscopic Resection of T1 Colorectal Cancer: A Multicenter Cohort Study

Yara Backes; W. H. de Vos tot Nederveen Cappel; J van Bergeijk; F ter Borg; Matthijs P. Schwartz; B.W.M. Spanier; Joost M.J. Geesing; Koen Kessels; M Kerkhof; John N. Groen; Frank H.J. Wolfhagen; Tom Seerden; N van Lelyveld; G J A Offerhaus; Peter D. Siersema; Miangela M. Lacle; Leon M. Moons

Objectives:The decision to perform secondary surgery after endoscopic resection of T1 colorectal cancer (CRC) depends on the risk of lymph node metastasis and the risk of incomplete resection. We aimed to examine the incidence and risk factors for incomplete endoscopic resection of T1 CRC after a macroscopic radical endoscopic resection.Methods:Data from patients treated between 2000 and 2014 with macroscopic complete endoscopic resection of T1 CRC were collected from 13 hospitals. Incomplete resection was defined as local recurrence at the polypectomy site during follow-up or malignant tissue in the surgically resected specimen in case secondary surgery was performed. Multivariate regression analysis was performed to analyze factors associated with incomplete resection.Results:In total, 877 patients with a median follow-up time of 36.5 months (interquartile range 16.0–68.3) were included, in whom secondary surgery was performed in 358 patients (40.8%). Incomplete resection was observed in 30 patients (3.4%; 95% confidence interval (CI) 2.3–4.6%). Incomplete resection rate was 0.7% (95% CI 0–2.1%) in low-risk T1 CRC vs. 4.4% (95% CI 2.7–6.5%) in high-risk T1 CRC (P=0.04). Overall adverse outcome rate (incomplete resection or metastasis) was 2.1% (95% CI 0–5.0%) in low-risk T1 CRC vs. 11.7% (95% CI 8.8–14.6%) in high-risk T1 CRC (P=0.001). Piecemeal resection (adjusted odds ratio 2.60; 95% CI 1.20–5.61, P=0.02) and non-pedunculated morphology (adjusted odds ratio 2.18; 95% CI 1.01–4.70, P=0.05) were independent risk factors for incomplete resection. Among patients in whom no additional surgery was performed, who developed recurrent cancer, 41.7% (95% CI 20.8–62.5%) died as a result of recurrent cancer.Conclusions:In the absence of histological high-risk factors, a ‘wait-and-see’ policy with limited follow-up is justified. Piecemeal resection and non-pedunculated morphology are independent risk factors for incomplete endoscopic resection of T1 CRC.


Rare diseases (Austin, Tex.) | 2017

Sending family history questionnaires to patients before a colonoscopy improves genetic counseling for hereditary colorectal cancer

Koen Kessels; Joey Eisinger; Tom G. W. Letteboer; G. Johan A. Offerhaus; Peter D. Siersema; Leon M. Moons

To investigate whether sending a family history questionnaire to patients prior to undergoing colonoscopy results in an increased availability of family history and better genetic counseling.


Diseases of The Colon & Rectum | 2013

Adherence to microsatellite instability testing in young-onset colorectal cancer patients

Koen Kessels; Herma H. Fidder; Nicolette L. de Groot; Tom G. W. Letteboer; Robin Timmer; Thijs van Dalen; E. C. J. Consten; G. Johan A. Offerhaus; Peter D. Siersema

BACKGROUND: In 1997, the Bethesda guidelines recommended microsatellite instability testing for colorectal cancer in patients younger than 45 years to screen for Lynch syndrome. In 2004, these guidelines were revised to set the screening age at younger than 50 years. OBJECTIVE: The aim of this study was to investigate to what extent these guidelines were followed in young patients with colorectal cancer in the Mid-Netherlands and to identify the predictors of nonadherence. DESIGN: This is a retrospective cohort study. SETTINGS: This study was conducted in 1 academic and 5 nonacademic hospitals. PATIENTS: All patients diagnosed with colorectal cancer younger than 45 years in the period 1999 to 2004 and younger than 50 years in the period 2005 to 2008 were included. Patients known to be affected by or at risk for Lynch syndrome before diagnosis were excluded. MAIN OUTCOME MEASURES: Patient and tumor characteristics, including microsatellite instability testing results, were collected from the database of the Comprehensive Cancer Center, the National Pathological Archive, participating hospitals, and the regional institute of clinical genetics. Logistic regression analysis was performed to detect a trend in adherence over the years and to identify the predictors of nonadherence. RESULTS: A total of 335 patients were identified. Microsatellite instability testing was performed in 130/335 (39%) patients. Adherence did not improve in the period 1999 to 2008. We found that older age at diagnosis (OR 0.96, 95% CI 0.92–1.00), male sex (OR 0.60, 95% CI 0.38–0.95), and stage IV colorectal cancer (OR 0.45, 95% CI 0.24–0.84) were independent predictors of nonadherence, whereas proximal tumor localization, poor differentiation, and mucinous histology were not. LIMITATIONS: This study was limited by its retrospective design. CONCLUSIONS: Adherence to the Bethesda guidelines in young-onset colorectal cancer is low, particularly in older and male patients and in patients with metastatic disease, which suggests that efforts to improve adherence are needed.


Modern Pathology | 2017

Diagnosis of T1 colorectal cancer in pedunculated polyps in daily clinical practice : a multicenter study

Yara Backes; Leon M. Moons; Marco R Novelli; Jeroen van Bergeijk; John N. Groen; Tom Seerden; Matthijs P. Schwartz; Wouter H. de Vos tot Nederveen Cappel; B.W.M. Spanier; Joost M.J. Geesing; Koen Kessels; Marjon Kerkhof; Peter D. Siersema; G. Johan A. Offerhaus; Anya N. A. Milne; Miangela M. Lacle

T1 colorectal cancer can be mimicked by pseudo-invasion in pedunculated polyps. British guidelines are currently one of the few which recommend diagnostic confirmation of T1 colorectal cancer by a second pathologist. The aim of this study was to provide insights into the accuracy of histological diagnosis of pedunculated T1 colorectal cancer in daily clinical practice. A sample of 128 cases diagnosed as pedunculated T1 colorectal cancer between 2000 and 2014 from 10 Dutch hospitals was selected for histological review. Firstly, two Dutch expert gastrointestinal pathologists reviewed all hematoxylin-eosin stained slides. In 20 cases the diagnosis T1 colorectal cancer was not confirmed (20/128; 16%). The discordant cases were subsequently discussed with a third Dutch gastrointestinal pathologist and a consensus diagnosis was agreed. The revised diagnoses were pseudo-invasion in 10 cases (10/128; 8%), high-grade dysplasia in 4 cases (4/128; 3%), and equivocal in 6 cases (6/128; 5%). To further validate the consensus diagnosis, the discordant cases were reviewed by an independent expert pathologist from the United Kingdom. A total of 39 cases were reviewed blindly including the 20 cases with a revised diagnosis and 19 control cases where the Dutch expert panel agreed with the original reporting pathologists diagnosis. In 19 of the 20 cases with a revised diagnosis the British pathologist agreed that T1 colorectal cancer could not be confirmed. Additionally, amongst the 19 control cases the British pathologist was unable to confirm T1 colorectal cancer in a further 4 cases and was equivocal in 3 cases. In conclusion, both generalist and expert pathologists experience diagnostic difficulty distinguishing pseudo-invasion and high-grade dysplasia from T1 colorectal cancer. In order to prevent overtreatment, review of the histology of pedunculated T1 colorectal cancers by a second pathologist should be considered with discussion of these cases at a multidisciplinary meeting.


Clinical Gastroenterology and Hepatology | 2018

Pedunculated Morphology of T1 Colorectal Tumors Associates With Reduced Risk of Adverse Outcome

Koen Kessels; Yara Backes; Sjoerd G. Elias; Aneya Van Den Blink; G. Johan A. Offerhaus; Jeroen van Bergeijk; John N. Groen; Tom Seerden; Matthijs P. Schwartz; Wouter H. de Vos tot Nederveen Cappel; B.W.M. Spanier; Joost M.J. Geesing; Marjon Kerkhof; Peter D. Siersema; Paul Didden; Jurjen J. Boonstra; Lorenza Alvarez Herrero; Frank H.J. Wolfhagen; Frank ter Borg; Anja U. van Lent; Jochim S. Terhaar sive Droste; Wouter L. Hazen; Ruud W.M. Schrauwen; Frank P. Vleggaar; Miangela M. Lacle; Leon M. Moons

BACKGROUND & AIMS Risk stratification for adverse events, such as metastasis to lymph nodes, is based only on histologic features of tumors. We aimed to compare adverse outcomes of pedunculated vs nonpedunculated T1 colorectal cancers (CRC). METHODS We performed a retrospective study of 1656 patients diagnosed with T1CRC from 2000 through 2014 at 14 hospitals in The Netherlands. The median follow‐up time of patients was 42.5 months (interquartile range, 18.5–77.5 mo). We evaluated the association between tumor morphology and the primary composite end point, adverse outcome, adjusted for clinical variables, histologic variables, resection margins, and treatment approach. Adverse outcome was defined as metastasis to lymph nodes, distant metastases, local recurrence, or residual tissue. Secondary end points were tumor metastasis, recurrence, and incomplete resection. RESULTS Adverse outcome occurred in 67 of 723 patients (9.3%) with pedunculated T1CRCs vs 155 of 933 patients (16.6%) with nonpedunculated T1CRCs. Pedunculated morphology was independently associated with decreased risk of adverse outcome (adjusted odds ratio [OR], 0.59; 95% CI, 0.42–0.83; P = .003). Metastasis, incomplete resection, and recurrence were observed in 5.8%, 4.6%, and 3.9% of pedunculated T1CRCs vs 10.6%, 8.0%, and 6.6% of nonpedunculated T1CRCs, respectively. Pedunculated morphology was independently associated with a reduced risk of metastasis (adjusted OR, 0.62; 95% CI, 0.41–0.94; P = .03), incomplete resection (adjusted OR, 0.57; 95% CI, 0.36–0.91; P = .02), and recurrence (adjusted hazard ratio, 0.52; 95% CI, 0.32–0.85; P = .009). Metastasis, incomplete resection, and recurrence did not differ significantly between low‐risk pedunculated vs nonpedunculated T1CRCs (0.8% vs 2.9%, P = .38; 1.5% vs 0%, P = .99; 1.5% vs 0%; P = .99). However, incomplete resection and recurrence were significantly lower for high‐risk pedunculated vs nonpedunculated T1CRCs (6.5% vs 12.5%; P = .007; 4.4% vs 8.6%; P = .03). CONCLUSIONS In a retrospective study of patients with T1CRC, we found pedunculated morphology to be associated independently with a decreased risk of adverse outcome in a T1CRC population at high risk of adverse outcome. Incorporating morphologic features of tumors in risk assessment could help predict outcomes of patients with T1CRC and help identify the best candidates for surgery.


Gut | 2018

Endoscopic resection of high-risk T1 colorectal carcinoma prior to surgical resection has no adverse effect on long-term outcomes

Anouk Overwater; Koen Kessels; Sjoerd G. Elias; Yara Backes; B.W.M. Spanier; Tom Seerden; Hendrikus J. Pullens; W. H. de Vos tot Nederveen Cappel; A van den Blink; G J A Offerhaus; J van Bergeijk; M Kerkhof; Joost M.J. Geesing; John N. Groen; N van Lelyveld; F ter Borg; Frank H.J. Wolfhagen; Peter D. Siersema; Miangela M. Lacle; Leon M. Moons


BMC Medicine | 2017

The prognostic value of lymph node yield in the earliest stage of colorectal cancer: a multicenter cohort study

Yara Backes; Sjoerd G. Elias; Bibie S Bhoelan; John N. Groen; Jeroen van Bergeijk; Tom Seerden; Hendrikus J. Pullens; B.W.M. Spanier; Joost M.J. Geesing; Koen Kessels; Marjon Kerkhof; Peter D. Siersema; Wouter H. de Vos tot Nederveen Cappel; Niels van Lelyveld; Frank H.J. Wolfhagen; Frank ter Borg; G. Johan A. Offerhaus; Miangela M. Lacle; Leon M. Moons


Gastrointestinal Endoscopy | 2017

Extent of unnecessary surgery for benign rectal polyps in the Netherlands

Laurien J. van Nimwegen; Leon M. Moons; Joost M.J. Geesing; L. René Arensman; Miangela M. Lacle; Ivo A. M. J. Broeders; Peter P. Viergever; John N. Groen; Koen Kessels; Matthijs P. Schwartz

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Peter D. Siersema

Radboud University Nijmegen

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Marjon Kerkhof

Erasmus University Rotterdam

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