Barbara A. Bastiaansen

Incidence of Colonic Neoplasia in Patients With Serrated Polyposis Syndrome Who Undergo Annual Endoscopic Surveillance

BACKGROUND & AIMS Patients with serrated polyposis syndrome (SPS) are advised to undergo endoscopic surveillance for early detection of polyps and prevention of colorectal cancer (CRC). The optimal surveillance and treatment regimen is unknown. We performed a prospective study to evaluate a standardized endoscopic treatment protocol in a large cohort of patients with SPS. METHODS We followed a cohort of patients with SPS who received annual endoscopic surveillance at the Academic Medical Centre in Amsterdam, The Netherlands from January 2007 through December 2012. All patients underwent clearing colonoscopy with removal of all polyps ≥3 mm. After clearance, subsequent follow-up colonoscopies were scheduled annually. The primary outcomes measure was the incidence of CRC and polyps. Secondary outcomes were the incidence of complications and the rate of preventive surgery. RESULTS Successful endoscopic clearance of all polyps ≥3 mm was achieved in 41 of 50 (82%) patients. During subsequent annual surveillance, with a median follow-up time of 3.1 years (interquartile range, 1.5-4.3 years), CRC was not detected. The cumulative risks of detecting CRC, advanced adenomas, or large (≥10 mm) serrated polyps after 3 surveillance colonoscopies were 0%, 9%, 34%, respectively. Twelve patients (24%) were referred for preventive surgery; 9 at initial colonoscopy and 3 during surveillance. Perforations or severe bleeding did not occur. CONCLUSIONS Annual surveillance with complete removal of all polyps ≥3 mm with timely referral of selected high-risk patients for prophylactic surgery prevents development of CRC in SPS patients without significant morbidity. Considering the substantial risk of polyp recurrence, close endoscopic surveillance in SPS seems warranted. www.trialregister.nl ID NTR2757.

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.

Polyp Morphology: An Interobserver Evaluation for the Paris Classification Among International Experts

OBJECTIVES:The Paris classification is an international classification system for describing polyp morphology. Thus far, the validity and reproducibility of this classification have not been assessed. We aimed to determine the interobserver agreement for the Paris classification among seven Western expert endoscopists.METHODS:A total of 85 short endoscopic video clips depicting polyps were created and assessed by seven expert endoscopists according to the Paris classification. After a digital training module, the same 85 polyps were assessed again. We calculated the interobserver agreement with a Fleiss kappa and as the proportion of pairwise agreement.RESULTS:The interobserver agreement of the Paris classification among seven experts was moderate with a Fleiss kappa of 0.42 and a mean pairwise agreement of 67%. The proportion of lesions assessed as “flat” by the experts ranged between 13 and 40% (P<0.001). After the digital training, the interobserver agreement did not change (kappa 0.38, pairwise agreement 60%).CONCLUSIONS:Our study is the first to validate the Paris classification for polyp morphology. We demonstrated only a moderate interobserver agreement among international Western experts for this classification system. Our data suggest that, in its current version, the use of this classification system in daily practice is questionable and it is unsuitable for comparative endoscopic research. We therefore suggest introduction of a simplification of the classification system.

Automatic optical diagnosis of small colorectal lesions by laser-induced autofluorescence

BACKGROUND AND STUDY AIMS Endoscopic optical diagnosis can potentially replace histopathological evaluation of small colorectal lesions. The aim of this study was to evaluate diagnostic performance of WavSTAT, a novel system for automatic optical diagnosis based on laser-induced autofluorescence spectroscopy. PATIENTS AND METHODS Consecutive patients who were scheduled for colonoscopy were included in the study. Each detected lesion with a size of ≤ 9 mm was differentiated using high resolution endoscopy (HRE) by the endoscopist, who then reported this as a low or high confidence call. Thereafter, all lesions were analyzed using WavSTAT. Histopathology was used as the reference standard. The primary outcome measures were the accuracy of WavSTAT to differentiate between adenomatous and nonadenomatous lesions, and the accuracy of an algorithm combining HRE (lesions differentiated with high confidence) and WavSTAT (all remaining lesions). The secondary outcome measure was the accuracy of on-site recommended surveillance intervals. RESULTS At total of 87 patients with 207 small colorectal lesions were evaluated. Accuracy and negative predictive value of WavSTAT were 74.4 % and 73.5 %, respectively. The corresponding figures for the algorithm were 79.2 % and 73.9 %, respectively. Accuracy of on-site recommended surveillance interval was 73.7 % for WavSTAT alone and 77.2 % for the algorithm of HRE and WavSTAT. CONCLUSIONS Both accuracy of WavSTAT alone and the algorithm combining HRE with WavSTAT proved to be insufficient for the in vivo differentiation of small colorectal lesions, and do not fulfill American Society for Gastrointestinal Endoscopy performance thresholds for assessment of diminutive lesions. Future studies should assess whether combining WavSTAT with more advanced imaging techniques could result in a higher accuracy.Netherlands Trial Registry (NTR 3235).

Robotic-assisted flexible colonoscopy: preliminary safety and efficiency in humans.

BACKGROUND AND AIMS The flexible endoscope is used as a platform for minimally invasive interventions. However, control of the conventional endoscope and multiple instruments is difficult. Robotic assistance could provide a solution and better control for a single operator. A novel platform should also enable interventions in areas that are currently difficult to reach. This study evaluates the safety and efficacy of a robotic platform that guides a conventional endoscope through the large bowel. METHODS Adult patients scheduled for routine diagnostic colonoscopy were included in this feasibility study. The endoscope was introduced using a robotic add-on to provide tip bending and air/water actuation. The endoscopist directly controlled the endoscope shaft. Upon cecal intubation, the add-on was detached and the procedure continued using conventional control. Primary evaluation parameters were the number of serious adverse events and the percentage of successful cecal intubations. RESULTS The procedure was performed on 22 consecutive patients who all gave informed consent. There were no serious adverse events. Cecal intubation was successful in 15 patients (68%) using the robotic add-on. Six cases were completed after conversion to conventional control: 3 cases were converted to pass sharp angulation in the flexures and 3 cases were converted after technical difficulties. One case was not successful with either technique because of severe diverticulosis. CONCLUSIONS The robotic add-on steering module allows safe endoscope intubation to reach intervention sites throughout the large bowel. The next step is to clinically evaluate complementary instrument and shaft-guiding modules in therapeutic procedures.

Extracolonic cancer risk in Dutch patients with APC (adenomatous polyposis coli)-associated polyposis

Background Screening of patients with familial adenomatous polyposis (FAP) have led to a substantial reduction in mortality due to colorectal cancer (CRC). Recent guidelines suggest that surveillance of non-intestinal malignancies should also be considered in those patients. However, the value of these surveillance programmes is unknown. The aims of this study were (1) to assess the occurrence of extracolonic malignancies in a large series of adenomatous polyposis coli (APC) mutation carriers and (2) to evaluate the causes of death. Methods All APC mutation carriers were selected from the Dutch polyposis registry. Data on causes of death were collected. Pathology reports were retrieved from the Dutch Pathology Registry. Results A total of 85 extracolonic malignancies were diagnosed in 74 of 582 APC mutation carriers. Duodenal and skin cancers were the most prevalent cancers. Thyroid cancer was observed in only 1.5% of the cases. The main cause of death was cancer (59% of all deaths), with 42% due to CRC and 21% due to duodenal cancer. One patient died from thyroid cancer. The second and third most common causes of death were cardiovascular disease (13% of all deaths) and desmoid tumours (11% of all deaths), respectively. Conclusion Extending surveillance programmes to other cancers will not contribute significantly to the survival of patients with FAP.

Polypectomy skills of gastroenterology fellows: can we improve them?

Background and aims: Currently, most training programs for gastroenterology (GI) fellows lack systematic training in polypectomy. Systematic education and direct feedback with the direct observational polypectomy skills (DOPyS) method is a simple and inexpensive way to train GI fellows in practical endoscopy. Our primary aim was to evaluate whether a lecture-based training course could improve the polypectomy skills of GI fellows. As a secondary aim, the interobserver agreement among the three assessors was evaluated. Participants and methods: We invited GI fellows to record five polypectomies, after which they attended a training course consisting of three lectures on polyps and polypectomy methods given by expert endoscopists. After training, the fellows recorded five polypectomies again. All videos were blindly assessed by three expert endoscopists, who used the DOPyS method. Results: Eight GI fellows participated in this study. There was no significant difference in the median overall competency scores before and after training; before training, 25 % (10/40) of the polypectomies were scored as “pass,” compared with 37.5 % (15/40) after training (P = 0.56). The interobserver agreement among the experts was fair (intraclass correlation coefficient [ICC] 0.34, 95 % confidence interval [CI] 0.14 – 0.52). Conclusions: Our lecture-based training course did not result in an improvement in overall competency scores for the polypectomy skills of GI fellows. Besides, the overall quality of the polypectomy techniques of the fellows was considered low. To optimize polypectomy training and competency, we believe that direct feedback in the endoscopy suite and hands-on training by dedicated teachers are essential.

Optical diagnosis of malignant colorectal polyps: is it feasible?

Background and study aims: As colorectal cancer screening programs are being implemented worldwide, an increasing number of early (T1) cancers are being diagnosed. These cancers should be recognized during colonoscopy because they require a specific therapeutic approach. Several studies have shown that Asian experts can reliably recognize T1 cancers during colonoscopy. In daily practice, however, accurate endoscopic diagnosis of T1 cancers still seems challenging. We evaluated the performance of optical diagnosis of T1 cancers by European colonoscopy experts, general gastroenterologists and gastrointestinal fellows. Patients and methods: We collected endoscopic images of 43 colonic lesions: 19 T1 cancers (excluding intramucosal carcinoma) and 24 benign polyps ranging from 7 mm to 30 mm in size. Seven colonoscopy experts, 7 general gastroenterologists, and 14 gastrointestinal fellows assessed these images. We calculated sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) and their 95 % confidence intervals for optical diagnosis of T1 cancers. Results: Overall sensitivity for correct diagnosis of T1 cancers was 60 % (95 % CI;45 – 72). Sensitivity was highest for experts (67 %: 95 %CI; 48 – 81), when compared to general gastroenterologists (53 %: 95 %CI; 37 – 69) and gastrointestinal fellows (59 %: 95 %CI;45 – 72). The overall NPV was 75 % (95 %CI;60 – 86); NPV was lowest for general gastroenterologists 72 % (95 %CI;57 – 83) vs 78 % (95 %CI;63 – 89) for experts and 75 % (95 %CI;60 – 85) for gastrointestinal fellows. Conclusions: In this image-based study, both sensitivity for the optical diagnosis of a T1 cancer and NPV for excluding a T1 cancer were insufficient. Experts performed best with a sensitivity of 67 % and a NPV of 78 %, while the performance of fellows in the last year of training was comparable to that of experts. Our study indicates that training for endoscopic diagnosis for T1 cancers is urgently needed to ensure optimal clinical practice for treatment of these lesions.

Cap-assisted forward-viewing endoscopy to visualize the ampulla of Vater and the duodenum in patients with familial adenomatous polyposis.

Background and study aims Guidelines recommend surveillance endoscopy with both forward- and side-viewing endoscopes to identify duodenal and ampullary adenomas in patients with familial adenomatous polyposis (FAP). We hypothesized that both the duodenum and the ampulla of Vater can be completely visualized during cap-assisted forward-viewing endoscopy. Patients and methods A total of 40 patients with FAP underwent forward-viewing endoscopy with a short cap attached to the tip of the gastroscope, with the aim of visualizing both the duodenum and the ampulla of Vater. If unsuccessful, the procedure was followed by a side-viewing endoscopy. Adverse events were reported. Results The duodenum, including the ampulla of Vater, was completely visualized using the cap in 38/40 patients (95.0 %). The ampulla could not be visualized using the cap in two patients, both of whom underwent additional side-viewing endoscopy, which was successful. No adverse events occurred. Conclusions This study showed that cap-assisted endoscopy can be used effectively and safely to visualize both the duodenum and the ampulla of Vater in patients with FAP. This practice might reduce burden, time, and costs of an additional side-viewing endoscopy.

Adrenal Lesions in Patients With (attenuated) Familial Adenomatous Polyposis and Mutyh-associated Polyposis

BACKGROUND: The reported proportion of patients with familial adenomatous polyposis who have adrenal lesions varies between 7% and 13% compared with 4% in the general population; the prevalence of adrenal lesions in patients with attenuated familial adenomatous polyposis and MUTYH-associated polyposis is unknown. Data on the clinical relevance and clinical course are limited. OBJECTIVE: We aimed to report on the frequency, characteristics, and progression of adrenal lesions in polyposis patients. DESIGN: This was a historical cohort study. SETTINGS: The study was performed at the Academic Medical Center, Amsterdam. PATIENTS: All of the patients with familial adenomatous polyposis, attenuated familial adenomatous polyposis, and MUTYH-associated polyposis were included. Medical charts and imaging reports were analyzed for data on adrenal lesions. A radiologist reassessed all of the images. Patients had not routinely been screened for adrenal lesions. MAIN OUTCOME MEASURES: The frequency, characteristics, and progression of adrenal lesions in patients with polyposis who underwent abdominal imaging were assessed. Findings were compared with a reference. RESULTS: A total of 39 adrenal lesions were identified in 23 (26%) of 90 patients with familial adenomatous polyposis, 2 (18%) of 11 with attenuated familial adenomatous polyposis, and 5 (24%) of 21 with MUTYH-associated polyposis. Mean age at time of detection was 50.7 years (range, 17.1–83.3 y). Median lesion size at baseline was 1.4 cm (range, 1.0–5.0 cm) versus 1.7 cm (range, 1.0–5.7 cm) after a median of 3.5 years (range, 1.0–11.4 y). Two patients were diagnosed with a hyperfunctioning lesion, and 4 underwent adrenalectomy: 3 lesions appeared benign, and 1 was oncocytic of uncertain malignant potential. The OR for detecting at least 1 lesion in a patient with polyposis versus reference was 6.2 (95% CI, 3.2–12.3), with no significant differences in ORs among the 3 syndromes. LIMITATIONS: The study was limited by its retrospective design. CONCLUSIONS: Adrenal lesions are frequent in patients with polyposis who undergo abdominal imaging. They appear to follow a benign and slowly progressive course and are mostly nonhyperfunctioning. See Abstract Video at http://links.lww.com/DCR/A323.