Endoscopically removed rectal NETs: a nationwide cohort study.

PURPOSE: Rectal neuroendocrine tumours (NETs) often present as an incidental finding during colonoscopy. Complete endoscopic resection of low-grade NETs up to 10 mm is considered safe. Whether this is also safe for NETs up to 20 mm is unclear. We performed a nationwide study to determine the risk of lymph node and distant metastases in endoscopically removed NETs. METHODS: All endoscopically removed rectal NETs between 1990 and 2010 were identified using the national pathology database (PALGA). Each NET was stratified according to size, grade and resection margin. Follow-up was until February 2016. RESULTS: Between 1990 and 2010, a total of 310 NETs smaller than 20 mm were endoscopically removed. Mean size of NETs was 7.4 mm (SD 3.5). In 49% of NETs (n = 153), no grade (G) could be assessed from the pathology report, 1% was G2 (n = 3), and the remaining NETs were G1. Median follow up was 11.6 years (range 4.9-26.0). During follow-up, 30 patients underwent surgical resection. Lymph node or distant metastasis was seen in 3 patients (1%) which all had a grade 2 NET. Mean time from endoscopic resection to diagnosis of metastases was 6.1 years (95% CI 2.9-9.2). CONCLUSION: No lymph node or distant metastases were seen in endoscopically removed G1 NETs up to 20 mm during the long follow-up of this nationwide study. This adds evidence to the ENET guideline that endoscopic resection of G1 NETs up to 20 mm appears to be safe.

Low Incidence of Advanced Neoplasia in Serrated Polyposis Syndrome After (Sub)total Colectomy: Results of a 5-Year International Prospective Cohort Study.

INTRODUCTION: Serrated polyposis syndrome (SPS) is accompanied by a substantially increased colorectal cancer (CRC) risk. To prevent or treat CRC in patients with a very high polyp burden, (sub)total colectomy with ileorectal or ileosigmoidal anastomosis is regularly performed. The CRC risk after (sub)total colectomy might be decreased, but evidence is lacking. We aimed to assess the yield of endoscopic surveillance in patients with SPS who underwent (sub)total colectomy. METHODS: For this post hoc analysis, we used prospectively collected data from a large international prospective cohort study. We included patients diagnosed with SPS (World Health Organization type I and/or III) who underwent (sub)total colectomy. Primary endpoint was the cumulative 5-year incidence of CRC and advanced neoplasia (AN). RESULTS: Forty-eight patients (mean age 61 [±7.8]; 52% men) were included and followed up for a median of 4.7 years (interquartile range 4.7-5.1). None of the patients developed CRC during follow-up. Five patients developed AN, corresponding to a cumulative 5-year AN incidence of 13% (95% confidence interval 1.2-23). In 4 patients, AN was diagnosed at the first surveillance endoscopy after study inclusion, and in 1 patient, AN was detected during subsequent rounds of surveillance. The risk of AN was similar for patients with ileorectal and ileosigmoidal anastomosis (logrank P = 0.83). DISCUSSION: (Sub)total colectomy mitigates much of the excess risk of CRC in patients with SPS. Advanced neoplasms are mainly detected at the first endoscopy after (sub)total colectomy. Based on these results, after the first surveillance, intervals might be extended beyond the currently recommended 1-2 years.

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

OBJECTIVE: It is difficult to predict the presence of histological risk factors for lymph node metastasis (LNM) before endoscopic treatment of T1 colorectal cancer (CRC). Therefore, endoscopic therapy is propagated to obtain adequate histological staging. We examined whether secondary surgery following endoscopic resection of high-risk T1 CRC does not have a negative effect on patients' outcomes compared with primary surgery. DESIGN: Patients with T1 CRC with one or more histological risk factors for LNM (high risk) and treated with primary or secondary surgery between 2000 and 2014 in 13 hospitals were identified in the Netherlands Cancer Registry. Additional data were collected from hospital records, endoscopy, radiology and pathology reports. A propensity score analysis was performed using inverse probability weighting (IPW) to correct for confounding by indication. RESULTS: 602 patients were eligible for analysis (263 primary; 339 secondary surgery). Overall, 34 recurrences were observed (5.6%). After adjusting with IPW, no differences were observed between primary and secondary surgery for the presence of LNM (OR 0.97; 95% CI 0.49 to 1.93; p=0.940) and recurrence during follow-up (HR 0.97; 95% CI 0.41 to 2.34; p=0.954). Further adjusting for lymphovascular invasion, depth of invasion and number of retrieved lymph nodes did not alter this outcome. CONCLUSIONS: Our data do not support an increased risk of LNM or recurrence after secondary surgery compared with primary surgery. Therefore, an attempt for an en-bloc resection of a possible T1 CRC without evident signs of deep invasion seems justified in order to prevent surgery of low-risk T1 CRC in a significant proportion of patients.

Clinical risk factors of colorectal cancer in patients with serrated polyposis syndrome: a multicentre cohort analysis.

OBJECTIVE: Serrated polyposis syndrome (SPS) is accompanied by an increased risk of colorectal cancer (CRC). Patients fulfilling the clinical criteria, as defined by the WHO, have a wide variation in CRC risk. We aimed to assess risk factors for CRC in a large cohort of patients with SPS and to evaluate the risk of CRC during surveillance. DESIGN: In this retrospective cohort analysis, all patients with SPS from seven centres in the Netherlands and two in the UK were enrolled. WHO criteria were used to diagnose SPS. Patients who only fulfilled WHO criterion-2, with IBD and/or a known hereditary CRC syndrome were excluded. RESULTS: In total, 434 patients with SPS were included for analysis; 127 (29.3%) were diagnosed with CRC. In a per-patient analysis ≥1 serrated polyp (SP) with dysplasia (OR 2.07; 95% CI 1.28 to 3.33), ≥1 advanced adenoma (OR 2.30; 95% CI 1.47 to 3.67) and the fulfilment of both WHO criteria 1 and 3 (OR 1.60; 95% CI 1.04 to 2.51) were associated with CRC, while a history of smoking was inversely associated with CRC (OR 0.36; 95% CI 0.23 to 0.56). Overall, 260 patients underwent surveillance after clearing of all relevant lesions, during which two patients were diagnosed with CRC, corresponding to 1.9 events/1000 person-years surveillance (95% CI 0.3 to 6.4). CONCLUSION: The presence of SPs containing dysplasia, advanced adenomas and/or combined WHO criteria 1 and 3 phenotype is associated with CRC in patients with SPS. Patients with a history of smoking show a lower risk of CRC, possibly due to a different pathogenesis of disease. The risk of developing CRC during surveillance is lower than previously reported in literature, which may reflect a more mature multicentre cohort with less selection bias.

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

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.

Regional differences in expression of TPH-1, SERT, 5-HT(3) and 5-HT(4) receptors in the human stomach and duodenum.

The aim of this study was to increase the understanding of the role of serotonergic signalling in normal gastroduodenal function at a molecular level. Mucosal biopsy specimens were collected from the fundus, antrum and duodenum of 11 healthy subjects. Serotonin (5-HT)-positive cells were counted and the mRNA levels of tryptophan hydroxylase (TPH), serotonin transporter (SERT), 5-HT(4) receptor and 5-HT(3) receptor subunits were quantified by real-time reverse transcription polymerase chain reaction. The number of 5-HT-positive cells was larger in the duodenum compared with the stomach (P < 0.001). Serotonin transport protein expression was 19-fold higher in the duodenum compared with the antrum and 457-fold higher compared with the fundus (P < 0.001). Tryptophan hydroxylase-1 expression was lower in the duodenum compared with the antrum and fundus (regional differences -2.3 and -3.6, respectively). The 5-HT(4) receptor and the 5-HT(3C) and 5-HT(3E) receptor subunits were more abundantly expressed in duodenum compared with the stomach (P < 0.001). The larger number of 5-HT-positive cells, the higher expression of 5-HT(3) and 5-HT(4) receptors, and in particularly the higher uptake capacity of 5-HT in the duodenum, point out to a more prominent role of serotonergic signalling at the mucosal level in the duodenum compared with the stomach.

The 5-HT4 antagonist R216073 does not affect gastric motor and sensory function in patients with functional dyspepsia.

BACKGROUND: Serotonin and the 5-HT4 receptor play an important role in gastrointestinal motor and sensory functions. While 5-HT4 agonists are known for their prokinetics properties, the effect of 5-HT4 antagonists on upper gastrointestinal functions is largely unknown. AIM: To assess the effect of a 5-HT4 receptor antagonist (R216073) on gastric relaxation and visceral sensitivity in patients with functional dyspepsia. Secondly, the influence of a functional polymorphism in the gene encoding the serotonin transport protein on drug response was determined. METHODS: A double-blind, randomized, placebo-controlled, two-period crossover study was performed in 20 functional dyspepsia patients. The effect of a single dose of 2,000 mg R216073 on gastric relaxation and sensitivity was tested using three-dimensional ultrasonography and a nutrient drinktest. RESULTS: R216073 did not affect partial gastric volumes or upper abdominal sensations scored during three-dimensional ultrasonography (P > 0.05). The maximum tolerated volume or upper abdominal sensations induced by the drinktest were not affected by R216073 (P > 0.05). The serotonin transport protein promoter polymorphism was not associated with any of the end-points of the study. CONCLUSIONS: A single dose of R216073 had no effect on fundic relaxation, drinking capacity, or upper abdominal symptoms in patients with functional dyspepsia.

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

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.

Serotonergic signalling in the stomach and duodenum of patients with gastroparesis.

Serotonin (5-HT) is involved in the regulation of motoric and sensory functions of the upper gastrointestinal tract. The aim of the current study was to determine whether serotonergic signalling is altered in patients with idiopathic gastroparesis. Mucosal biopsy specimens were collected from the duodenum, antrum and fundus of 11 patients with idiopathic gastroparesis and 11 healthy controls. Neuroendocrine cells, specifically 5-HT producing cells, were counted after immunohistochemistry, and non-neuronal mRNA expression levels of tryptophan hydroxylase (TPH)-1, 5-HT transport protein (SERT), 5-HT3 and 5-HT4 receptor were quantified by real time RT-PCR. The number of 5-HT producing cells was comparable between patients and controls. No difference in expression of TPH-1 (rate limiting enzyme in 5-HT biosynthetic pathway) and SERT (responsible for 5-HT uptake) was found between patients and controls (P > 0.05). In the duodenum, the expression of the 5-HT3 receptor subunits and the 5-HT4 receptor was comparable between both groups. However, the 5-HT4(c) splice variant was expressed more abundantly in healthy controls compared to patients (P = 0.015). This study suggests that the delayed gastric emptying and upper abdominal symptoms in idiopathic gastroparesis do not result from altered mucosal 5-HT biosynthetic and uptake capacity.

Candidate genotypes associated with functional dyspepsia.

There is accumulating evidence of a genetic predisposition for developing a functional gastrointestinal (GI) disorder. Identification of the genetic factors may improve understanding of underlying pathophysiological mechanisms. We aimed to test the association of functional polymorphisms in genes involved in serotonergic signalling and G-protein-mediated signal transduction, both affecting gastroduodenal sensory and motor function, with functional dyspepsia (FD). FD patients, send to our tertiary referral centre, were studied (n = 112). Healthy controls (n = 336) free of GI symptoms were matched 1 : 3 for age and gender. Polymorphisms in genes encoding the serotonin receptor type three A subunit (HTR3A), the serotonin transporter (SERT) and the G-protein beta3 subunit (GNB3) were analysed. The FD patients displayed a higher prevalence of the T allele of the GNB3 C825T polymorphism compared to healthy controls (OR = 1.60, 95% CI: 1.03-2.49, P = 0.038). No association between FD and the genotype of the insertion/deletion polymorphism in the promoter of SERT (SERT-P) or HTR3A C178T polymorphism was observed. Tertiary referral FD is associated with the 825T allele of the GNB3 gene. The increased signal transduction associated with this allele may contribute to the abnormalities in gastroduodenal sensory and motor function observed in FD.

Microbiological factors associated with neonatal necrotizing enterocolitis: protective effect of early antibiotic treatment.

AIM: The incidence of necrotizing enterocolitis (NEC) strongly increased in an neonatal intensive care unit (NICU) in 1997 and 1998 compared with previous years, which coincided with increased incidence of nosocomial sepsis. Specific risk factors related to this NICU and a possible relationship between NEC and nosocomial sepsis were studied retrospectively, including all patients with NEC since 1990 and matched controls. METHODS: Clinical and bacteriological data from the period before the development of NEC and a similar period for the controls were collected retrospectively and corrected for birthweight and gestational age. Statistical analysis was performed by a stepwise regression model. RESULTS: Data of 104 neonates with NEC and matched controls were analysed. The median day of onset of NEC was 12 d (range 1-63 d). Significant risk factors for NEC were: insertion of a peripheral artery catheter [odds ratio (OR) 2.3, 95% confidence interval (95% CI) 1.3-3.9] and a central venous catheter (OR 5.6, 95% CI 3.1-10.1), colonization with Klebsiella sp. (OR 3.4, 95% CI 1.5-7.5) and Escherichia coli (OR 2.1, 95% CI 1.0-4.5), and the occurrence of sepsis, in particular due to coagulase-negative staphylococci (OR 2.6, 95% CI 1.4-5.1). The risk for NEC was decreased after the early use (< 48 h after birth) of amoxicillin-clavulanate and gentamicin (OR 0.3, 95% CI 0.2-0.6). CONCLUSION: Insertion of central venous and peripheral arterial catheters is positively associated with NEC, as is colonization with the Gram-negative bacilli Klebsiella and E. coli and the occurrence of sepsis, particularly due to coagulase-negative staphylococci. Early treatment with amoxicillin-clavulanate and gentamicin is negatively associated with NEC and may be protective against NEC.