COMPUTER-AIDED DIAGNOSIS IMPROVES CHARACTERIZATION OF BARRETT'S NEOPLASIA BY GENERAL ENDOSCOPISTS.

BACKGROUND & AIMS: Characterization of visible abnormalities in Barrett esophagus (BE) patients can be challenging, especially for unexperienced endoscopists. This results in suboptimal diagnostic accuracy and poor inter-observer agreement. Computer-aided diagnosis (CADx) systems may assist endoscopists. We aimed to develop, validate and benchmark a CADx system for BE neoplasia. METHODS: The CADx system received pretraining with ImageNet with consecutive domain-specific pretraining with GastroNet which includes 5 million endoscopic images. It was subsequently trained and internally validated using 1,758 narrow-band imaging (NBI) images of early BE neoplasia (352 patients) and 1,838 NBI images of non-dysplastic BE (173 patients) from 8 international centers. CADx was tested prospectively on corresponding image and video test sets with 30 cases (20 patients) of BE neoplasia and 60 cases (31 patients) of non-dysplastic BE. The test set was benchmarked by 44 general endoscopists in two phases (phase 1: no CADx assistance; phase 2: with CADx assistance). Ten international BE experts provided additional benchmark performance. RESULTS: Stand-alone sensitivity and specificity of the CADx system were 100% and 98% for images and 93% and 96% for videos, respectively. CADx outperformed general endoscopists without CADx assistance in terms of sensitivity (p=0.04). Sensitivity and specificity of general endoscopist increased from 84% to 96% and 90 to 98% with CAD assistance (p<0.001), respectively. CADx assistance increased endoscopists' confidence in characterization (p<0.001). CADx performance was similar to Barrett experts. CONCLUSION: CADx assistance significantly increased characterization performance of BE neoplasia by general endoscopists to the level of expert endoscopists. The use of this CADx system may thereby improve daily Barrett surveillance.

Incidence and Prediction of Unrelated Mortality After Successful Endoscopic Eradication Therapy for Barrett's Neoplasia.

BACKGROUND & AIMS: Follow-up (FU) strategies after endoscopic eradication therapy (EET) for Barrett's neoplasia do not consider the risk of mortality from causes other than esophageal adenocarcinoma (EAC). We aimed to evaluate this risk during long-term FU, and to assess whether the Charlson Comorbidity Index (CCI) can predict mortality. METHODS: We included all patients with successful EET from the nationwide Barrett registry in the Netherlands. Data were merged with National Statistics for accurate mortality data. We evaluated annual mortality rates (AMRs, per 1000 person-years) and standardized mortality ratio for other-cause mortality. Performance of the CCI was evaluated by discrimination and calibration. RESULTS: We included 1154 patients with a mean age of 64 years (±9). During median 59 months (p25-p75 37-91; total 6375 person-years), 154 patients (13%) died from other causes than EAC (AMR, 24.1; 95% CI, 20.5-28.2), most commonly non-EAC cancers (n = 58), cardiovascular (n = 31), or pulmonary diseases (n = 26). Four patients died from recurrent EAC (AMR, 0.5; 95% CI, 0.1-1.4). Compared with the general Dutch population, mortality was significantly increased for patients in the lowest 3 age quartiles (ie, age <71 years). Validation of CCI in our population showed good discrimination (Concordance statistic, 0.78; 95% CI, 0.72-0.84) and fair calibration. CONCLUSION: The other-cause mortality risk after successful EET was more than 40 times higher (48; 95% CI, 15-99) than the risk of EAC-related mortality. Our findings reveal that younger post-EET patients exhibit a significantly reduced life expectancy when compared with the general population. Furthermore, they emphasize the strong predictive ability of CCI for long-term mortality after EET. This straightforward scoring system can inform decisions regarding personalized FU, including appropriate cessation timing. (NL7039).

Towards a robust and compact deep learning system for primary detection of early Barrett's neoplasia: Initial image-based results of training on a multi-center retrospectively collected data set.

INTRODUCTION: Endoscopic detection of early neoplasia in Barrett's esophagus is difficult. Computer Aided Detection (CADe) systems may assist in neoplasia detection. The aim of this study was to report the first steps in the development of a CADe system for Barrett's neoplasia and to evaluate its performance when compared with endoscopists. METHODS: This CADe system was developed by a consortium, consisting of the Amsterdam University Medical Center, Eindhoven University of Technology, and 15 international hospitals. After pretraining, the system was trained and validated using 1.713 neoplastic (564 patients) and 2.707 non-dysplastic Barrett's esophagus (NDBE; 665 patients) images. Neoplastic lesions were delineated by 14 experts. The performance of the CADe system was tested on three independent test sets. Test set 1 (50 neoplastic and 150 NDBE images) contained subtle neoplastic lesions representing challenging cases and was benchmarked by 52 general endoscopists. Test set 2 (50 neoplastic and 50 NDBE images) contained a heterogeneous case-mix of neoplastic lesions, representing distribution in clinical practice. Test set 3 (50 neoplastic and 150 NDBE images) contained prospectively collected imagery. The main outcome was correct classification of the images in terms of sensitivity. RESULTS: The sensitivity of the CADe system on test set 1 was 84%. For general endoscopists, sensitivity was 63%, corresponding to a neoplasia miss-rate of one-third of neoplastic lesions and a potential relative increase in neoplasia detection of 33% for CADe-assisted detection. The sensitivity of the CADe system on test sets 2 and 3 was 100% and 88%, respectively. The specificity of the CADe system varied for the three test sets between 64% and 66%. CONCLUSION: This study describes the first steps towards the establishment of an unprecedented data infrastructure for using machine learning to improve the endoscopic detection of Barrett's neoplasia. The CADe system detected neoplasia reliably and outperformed a large group of endoscopists in terms of sensitivity.

Clinical Relevance of Random Biopsies From the Esophagogastric Junction After Complete Eradication of Barrett's Esophagus is Low.

BACKGROUND & AIMS: Although random histological sampling from the esophagogastric junction (EGJ) after complete eradication of Barrett's esophagus (BE) is recommended, its clinical relevance is questionable. This study aimed to assess the incidence and long-term outcomes of findings from random EGJ biopsies in a nationwide cohort with long-term follow-up. METHODS: We included all patients with successful endoscopic eradication therapy (EET), defined as complete endoscopic eradication of all visible BE (CE-BE), for early BE neoplasia from the Dutch registry. Patients were treated and followed-up in 9 expert centers according to a joint protocol. Outcomes included the incidence of intestinal metaplasia (IM) at the EGJ (EGJ-IM) and the association between IM and visible (dysplastic) BE recurrence. RESULTS: A total of 1154 patients were included with a median follow-up of 43 months (interquartile range, 22-69 months). At the time of CE-BE, persisting EGJ-IM was found in 7% of patients (78/1154), which was reproduced during further follow-up in 46% of patients (42/78). No significant association existed between persisting EGJ-IM at CE-BE and recurrent non-dysplastic or dysplastic BE (hazard ratio [HR], 1.15; 95% confidence interval [CI], 0.63-2.13 and HR, 0.73; 95% CI, 0.17-3.06, respectively). Among patients with no EGJ-IM at the time of CE-BE (1043/1154; 90%), EGJ-IM recurred in 7% (72/1043) after a median of 21 months (interquartile range, 15-36 months), and was reproduced during further follow-up in 26% of patients (19/72). No association was found between recurrent EGJ-IM and non-dysplastic or dysplastic recurrence (HR, 1.18; 95% CI, 0.67-2.06 and HR, 0.27; 95% CI, 0.04-1.96, respectively). CONCLUSION: Because EGJ-IM was not associated with a higher risk for recurrent disease, we recommend to consider abandoning random EGJ sampling after successful EET, under the condition that care is provided in expert centers, and the esophagus, including the EGJ, is carefully inspected (Netherlands Trial Register, NL7309).

Dysplastic Recurrence After Successful Treatment for Early Barrett's Neoplasia: Development and Validation of a Prediction Model.

BACKGROUND & AIMS: The combination of endoscopic resection and radiofrequency ablation is the treatment of choice for eradication of Barrett's esophagus (BE) with dysplasia and/or early cancer. Currently, there are no evidence-based recommendations on how to survey patients after successful treatment, and most patients undergo frequent follow-up endoscopies. We aimed to develop and externally validate a prediction model for visible dysplastic recurrence, which can be used to personalize surveillance after treatment. METHODS: We collected data from the Dutch Barrett Expert Center Registry, a nationwide registry that captures outcomes from all patients with BE undergoing endoscopic treatment in the Netherlands in a centralized care setting. We used predictors related to demographics, severity of reflux, histologic status at baseline, and treatment characteristics. We built a Fine and Gray survival model with least absolute shrinkage and selection operator penalization to predict the incidence of visible dysplastic recurrence after initial successful treatment. The model was validated externally in patients with BE treated in Switzerland and Belgium. RESULTS: A total of 1154 patients with complete BE eradication were included for model building. During a mean endoscopic follow-up of 4 years, 38 patients developed recurrent disease (1.0%/person-year). The following characteristics were independently associated with recurrence (strongest to weakest predictor): a new visible lesion during treatment phase, higher number of endoscopic resection treatments, male sex, increasing BE length, high-grade dysplasia or cancer at baseline, and younger age. External validation showed a C-statistic of 0.91 (95% confidence interval, 0.86-0.94) with good calibration. CONCLUSIONS: This is the first externally validated model to predict visible dysplastic recurrence after successful endoscopic eradication treatment of BE with dysplasia or early cancer. On external validation, our model has good discrimination and calibration. This model can help clinicians and patients to determine a personalized follow-up strategy.

Development and External Validation of a Model to Predict Complex Treatment After Radiofrequency Ablation for Barrett's Esophagus With Early Neoplasia.

BACKGROUND & AIMS: Endoscopic eradication therapy for Barrett's esophagus (BE)-related neoplasia is safe and leads to complete eradication in the majority of patients. However, a subgroup will experience a more complex treatment course with a risk for failure or disease progression. Early identification of these patients may improve patient counseling and treatment outcomes. We aimed to develop a prognostic model for a complex treatment course. METHODS: We collected data from a nationwide registry that captures outcomes for all patients undergoing endoscopic eradication therapy for early BE neoplasia. A complex treatment course was defined as neoplastic progression, treatment failure, or the need for endoscopic resection during the radiofrequency ablation treatment phase. We developed a prognostic model using logistic regression. We externally validated our model in an independent registry. RESULTS: A total of 1386 patients were included, of whom 78 (6%) had a complex treatment course. Our model identified patients with a BE length of 9 cm or longer with a visible lesion containing high-grade dysplasia/cancer, and patients with less than 50% squamous conversion after radiofrequency ablation were identified as high risk for a complex treatment. This applied to 8% of the study population and included 93% of all treatment failures and 76% of all patients with advanced neoplastic progression. The model appeared robust in multiple sensitivity analyses and performed well in external validation (area under the curve, 0.84). CONCLUSIONS: We developed a prognostic model that identified patients with a BE length of 9 cm or longer and high-grade dysplasia/esophageal adenocarcinoma and those with poor squamous regeneration as high risk for a complex treatment course. The good performance in external validation suggests that it may be used in clinical management (Netherlands Trial Register: NL7039).

Analysis of metastases rates during follow-up after endoscopic resection of early "high-risk" esophageal adenocarcinoma.

BACKGROUND AND AIMS: After endoscopic resection (ER) of early esophageal adenocarcinoma (EAC), the optimal management of patients with high-risk histologic features for lymph node metastases (ie, submucosal invasion, poor differentiation grade, or lymphovascular invasion) remains unclear. We aimed to evaluate outcomes of endoscopic follow-up after ER for high-risk EAC. METHODS: For this retrospective cohort study, data were collected from all Dutch patients managed with endoscopic follow-up (endoscopy, EUS) after ER for high-risk EAC between 2008 and 2019. We distinguished 3 groups: intramucosal cancers with high-risk features, submucosal cancers with low-risk features, and submucosal cancers with high-risk features. The primary outcome was the annual risk for metastases during follow-up, stratified for baseline histology. RESULTS: One hundred twenty patients met the selection criteria. Median follow-up was 29 months (interquartile range, 15-48). Metastases were observed in 5 of 25 (annual risk, 6.9%; 95% confidence interval [CI], 3.0-15) high-risk intramucosal cancers, 1 of 55 (annual risk, .7%; 95% CI, 0-4.0) low-risk submucosal cancers, and 3 of 40 (annual risk, 3.0%; 95% CI, 0-7.0) high-risk submucosal cancers. CONCLUSIONS: Whereas the annual metastasis rate for high-risk submucosal EAC (3.0%) was somewhat lower than expected in comparison with previous reported percentages, the annual metastasis rate of 6.9% for high-risk intramucosal EAC is new and worrisome. This calls for further prospective studies and suggests that strict follow-up of this small subgroup is warranted until prospective data are available.

Impact of expert center endoscopic assessment of confirmed low grade dysplasia in Barrett's esophagus diagnosed in community hospitals.

BACKGROUND : The optimal management for patients with low grade dysplasia (LGD) in Barrett's esophagus (BE) is unclear. According to the Dutch national guideline, all patients with LGD with histological confirmation of the diagnosis by an expert pathologist (i. e. "confirmed LGD"), are referred for a dedicated re-staging endoscopy at an expert center. We aimed to assess the diagnostic value of re-staging endoscopy by an expert endoscopist for patients with confirmed LGD. METHODS : This retrospective cohort study included all patients with flat BE diagnosed in a community hospital who had confirmed LGD and were referred to one of the nine Barrett Expert Centers (BECs) in the Netherlands. The primary outcome was the proportion of patients with prevalent high grade dysplasia (HGD) or cancer during re-staging in a BEC. RESULTS : Of the 248 patients with confirmed LGD, re-staging in the BEC revealed HGD or cancer in 23 % (57/248). In 79 % (45/57), HGD or cancer in a newly detected visible lesion was diagnosed. Of the remaining patients, re-staging in the BEC showed a second diagnosis of confirmed LGD in 68 % (168/248), while the remaining 9 % (23/248) had nondysplastic BE. CONCLUSION : One quarter of patients with apparent flat BE with confirmed LGD diagnosed in a community hospital had prevalent HGD or cancer after re-staging at an expert center. This endorses the advice to refer patients with confirmed LGD, including in the absence of visible lesions, to an expert center for re-staging endoscopy.

Incidence and outcomes of poor healing and poor squamous regeneration after radiofrequency ablation therapy for early Barrett's neoplasia.

BACKGROUND: Endoscopic eradication therapy with radiofrequency ablation (RFA) is effective in most patients with Barrett's esophagus (BE). However, some patients experience poor healing and/or poor squamous regeneration. We evaluated incidence and treatment outcomes of poor healing and poor squamous regeneration. METHODS: We included all patients treated with RFA for early BE neoplasia from a nationwide Dutch registry based on a joint treatment protocol. Poor healing (active inflammatory changes or visible ulcerations ≥ 3 months post-RFA), poor squamous regeneration (< 50 % squamous regeneration), and treatment success (complete eradication of BE [CE-BE]) were evaluated. RESULTS: 1386 patients (median BE C2M5) underwent RFA with baseline low grade dysplasia (27 %), high grade dysplasia (30 %), or early cancer (43 %). In 134 patients with poor healing (10 %), additional time and acid suppression resulted in complete esophageal healing, and 67/134 (50 %) had normal squamous regeneration with 97 % CE-BE. Overall, 74 patients had poor squamous regeneration (5 %). Compared with patients with normal regeneration, patients with poor squamous regeneration had a higher risk for treatment failure (64 % vs. 2 %, relative risk [RR] 27 [95 % confidence interval [CI] 18-40]) and progression to advanced disease (15 % vs. < 1 %, RR 30 [95 %CI 12-81]). Higher body mass index, longer BE segment, reflux esophagitis, and < 50 % squamous regeneration after baseline endoscopic resection were independently associated with poor squamous regeneration in multivariable logistic regression. CONCLUSIONS: In half of the patients with poor healing, additional time and acid suppression led to normal squamous regeneration and excellent treatment outcomes. In patients with poor squamous regeneration, however, the risk for treatment failure and progression to advanced disease was significantly increased.

Favorable effect of endoscopic reassessment of clinically staged T2 esophageal adenocarcinoma: a multicenter prospective cohort study.

BACKGROUND : Clinical tumor stage of esophageal adenocarcinoma (EAC) is determined by endoscopic ultrasound and/or computed tomography scan, which have low accuracy for stages T1 and T2, potentially leading to overtreatment. We aimed to assess the proportion of cT2 EACs downstaged to cT1 after endoscopic reassessment (ERA) by an experienced interventional endoscopist. METHODS : We performed a prospective multicenter cohort study. Patients with cT2N0M0 EAC were included and underwent ERA. The primary outcome was proportion of cT2 EACs downstaged to cT1 after ERA. RESULTS : 15/25 included patients (60 %) were downstaged from cT2 to cT1 EAC after ERA and underwent attempted endoscopic resection. Endoscopic resection was aborted in 3/15 patients because of tumor invasion into the muscle layer; all three underwent successful surgical resection. Endoscopic resection was successful in 12/15 patients (80 %), all of whom had pT1 tumors. Overall, 10/25 (40 %) were treated with endoscopic resection alone. CONCLUSIONS : ERA downstaged about half of the cT2 tumors to cT1, rendering them suitable for endoscopic resection. ERA had substantial clinical impact on therapeutic management, preventing overtreatment in 40 % of patients.

Long-term outcomes after endoscopic treatment for Barrett's neoplasia with radiofrequency ablation ± endoscopic resection: results from the national Dutch database in a 10-year period.

OBJECTIVE: Radiofrequency ablation (RFA)±endoscopic resection (ER) is the preferred treatment for early neoplasia in Barrett's oesophagus (BE). We aimed to report short-term and long-term outcomes for all 1384 patients treated in the Netherlands (NL) from 2008 to 2018, with uniform treatment and follow-up (FU) in a centralised setting. DESIGN: Endoscopic therapy for early BE neoplasia in NL is centralised in nine expert centres with specifically trained endoscopists and pathologists that adhere to a joint protocol. Prospectively collected data are registered in a uniform database. Patients with low/high-grade dysplasia or low-risk cancer, were treated by ER of visible lesions followed by trimonthly RFA sessions of any residual BE until complete eradication of BE (CE-BE). Patients with ER alone were not included. RESULTS: After ER (62% of cases; 43% low-risk cancers) and median 1 circumferential and 2 focal RFA (p25-p75 0-1; 1-2) per patient, CE-BE was achieved in 94% (1270/1348). Adverse events occurred in 21% (268/1386), most commonly oesophageal stenosis (15%), all were managed endoscopically. A total of 1154 patients with CE-BE were analysed for long-term outcomes. During median 43 months (22-69) and 4 endoscopies (1-5), 38 patients developed dysplastic recurrence (3%, annual recurrence risk 1%), all were detected as endoscopically visible abnormalities. Random biopsies from a normal appearing cardia showed intestinal metaplasia (IM) in 14% and neoplasia in 0%. A finding of IM in the cardia was reproduced during further FU in only 33%, none progressed to neoplasia. Frequent FU visits in the first year of FU were not associated with recurrence risk. CONCLUSION: In a setting of centralised care, RFA±ER is effective for eradication of Barrett's related neoplasia and has remarkably low rates of dysplastic recurrence. Our data support more lenient FU intervals, with emphasis on careful endoscopic inspection. Random biopsies from neosquamous epithelium and cardia are of questionable value. NETHERLANDS TRIAL REGISTER NUMBER: NL7039.

Individual risk calculator to predict lymph node metastases in patients with submucosal (T1b) esophageal adenocarcinoma: a multicenter cohort study.

BACKGROUND: Lymph node metastasis (LNM) is possible after endoscopic resection of early esophageal adenocarcinoma (EAC). This study aimed to develop and internally validate a prediction model that estimates the individual risk of metastases in patients with pT1b EAC. METHODS: A nationwide, retrospective, multicenter cohort study was conducted in patients with pT1b EAC treated with endoscopic resection and/or surgery between 1989 and 2016. The primary end point was presence of LNM in surgical resection specimens or detection of metastases during follow-up. All resection specimens were histologically reassessed by specialist gastrointestinal pathologists. Subdistribution hazard regression analysis was used to develop the prediction model. The discriminative ability of this model was assessed using the c-statistic. RESULTS: 248 patients with pT1b EAC were included. Metastases were seen in 78 patients, and the 5-year cumulative incidence was 30.9 % (95 % confidence interval [CI] 25.1 %-36.8 %). The risk of metastases increased with submucosal invasion depth (subdistribution hazard ratio [SHR] 1.08, 95 %CI 1.02-1.14, for every increase of 500 µm), lymphovascular invasion (SHR 2.95, 95 %CI 1.95-4.45), and for larger tumors (SHR 1.23, 95 %CI 1.10-1.37, for every increase of 10 mm). The model demonstrated good discriminative ability (c-statistic 0.81, 95 %CI 0.75-0.86). CONCLUSIONS: A third of patients with pT1b EAC experienced metastases within 5 years. The probability of developing post-resection metastases was estimated with a personalized predicted risk score incorporating tumor invasion depth, tumor size, and lymphovascular invasion. This model requires external validation before implementation into clinical practice.

Extending treatment criteria for Barrett's neoplasia: results of a nationwide cohort of 138 endoscopic submucosal dissection procedures.

BACKGROUND: The use of endoscopic submucosal dissection (ESD) is gradually expanding for treatment of neoplasia in Barrett's esophagus (BE). We aimed to report outcomes of all ESDs for BE neoplasia performed in the Netherlands. METHODS: Retrospective assessment of outcomes, using treatment and follow-up data from a joint database. RESULTS: 130/138 patients had complete ESDs, with 126/130 (97 %) en bloc resections. Median (interquartile range (IQR)) procedure time was 121 minutes (90-180). Pathology findings were high grade dysplasia (HGD) (5 %) or esophageal adenocarcinoma (EAC) T1a (43 %) or T1b (52 %; 19 % sm1, 33 % ≥ sm2). Among resections of HGD or T1a EAC lesions, 87 % (95 %CI 75 %-92 %) were both en bloc and R0; the corresponding value for T1b EAC lesions was 49 % (36 %-60 %). Among R1 resections, 10/34 (29 %) showed residual cancer, all detected at first endoscopic follow-up. The remaining 24 patients (71 %) showed no residual neoplasia. Six of these patients underwent surgery with no residual tumor; the remaining 18 underwent endoscopic follow-up during median 31 months with 1 local recurrence (annual recurrence rate 2 %). Among R0 resections, annual local recurrence rate during median 27 months was 0.5 %. CONCLUSION: In expert hands, ESD allows safe removal of bulky intraluminal neoplasia and submucosal cancer. ESD of the latter showed R1 resection margins in 50 %, yet only one third had persisting neoplasia at follow-up. To better stratify R1 patients with an indication for additional surgery, repeat endoscopy after healing of the ESD might be a helpful possible prognostic factor for residual cancer.

Endoscopic full-thickness resection of T1 colorectal cancers: a retrospective analysis from a multicenter Dutch eFTR registry.

BACKGROUND: Complete endoscopic resection and accurate histological evaluation for T1 colorectal cancer (CRC) are critical in determining subsequent treatment. Endoscopic full-thickness resection (eFTR) is a new treatment option for T1 CRC < 2 cm. We aimed to report clinical outcomes and short-term results. METHODS: Consecutive eFTR procedures for T1 CRC, prospectively recorded in our national registry between November 2015 and April 2020, were retrospectively analyzed. Primary outcomes were technical success and R0 resection. Secondary outcomes were histological risk assessment, curative resection, adverse events, and short-term outcomes. RESULTS: We included 330 procedures: 132 primary resections and 198 secondary scar resections after incomplete T1 CRC resection. Overall technical success, R0 resection, and curative resection rates were 87.0 % (95 % confidence interval [CI] 82.7 %-90.3 %), 85.6 % (95 %CI 81.2 %-89.2 %), and 60.3 % (95 %CI 54.7 %-65.7 %). Curative resection rate was 23.7 % (95 %CI 15.9 %-33.6 %) for primary resection of T1 CRC and 60.8 % (95 %CI 50.4 %-70.4 %) after excluding deep submucosal invasion as a risk factor. Risk stratification was possible in 99.3 %. The severe adverse event rate was 2.2 %. Additional oncological surgery was performed in 49/320 (15.3 %), with residual cancer in 11/49 (22.4 %). Endoscopic follow-up was available in 200/242 (82.6 %), with a median of 4 months and residual cancer in 1 (0.5 %) following an incomplete resection. CONCLUSIONS: eFTR is relatively safe and effective for resection of small T1 CRC, both as primary and secondary treatment. eFTR can expand endoscopic treatment options for T1 CRC and could help to reduce surgical overtreatment. Future studies should focus on long-term outcomes.

Lymphovascular invasion quantification could improve risk prediction of lymph node metastases in patients with submucosal (T1b) esophageal adenocarcinoma.

AIM: To quantify lymphovascular invasion (LVI) and to assess the prognostic value in patients with pT1b esophageal adenocarcinoma. METHODS: In this nationwide, retrospective cohort study, patients were included if they were treated with surgery or endoscopic resection for pT1b esophageal adenocarcinoma. Primary endpoint was the presence of metastases, lymph node metastases, or distant metastases, in surgical resection specimens or during follow-up. A prediction model to identify risk factors for metastases was developed and internally validated. RESULTS: 248 patients were included. LVI was distributed as follows: no LVI (n = 196; 79.0%), 1 LVI focus (n = 16; 6.5%), 2-3 LVI foci (n = 21; 8.5%) and ≥4 LVI foci (n = 15; 6.0%). Seventy-eight patients had metastases. The risk of metastases was increased for tumors with 2-3 LVI foci [subdistribution hazard ratio (SHR) 3.39, 95% confidence interval (CI) 2.10-5.47] and ≥4 LVI foci (SHR 3.81, 95% CI 2.37-6.10). The prediction model demonstrated a good discriminative ability (c-statistic 0.81). CONCLUSION: The risk of metastases is higher when more LVI foci are present. Quantification of LVI could be useful for a more precise risk estimation of metastases. This model needs to be externally validated before implementation into clinical practice.

Endoscopic full-thickness resection (eFTR) of colorectal lesions: results from the Dutch colorectal eFTR registry.

BACKGROUND: Endoscopic full-thickness resection (eFTR) is a minimally invasive resection technique that allows definite diagnosis and treatment for complex colorectal lesions ≤ 30 mm unsuitable for conventional endoscopic resection. This study reports clinical outcomes from the Dutch colorectal eFTR registry. METHODS: Consecutive patients undergoing eFTR in 20 hospitals were prospectively included. The primary outcome was technical success, defined as macroscopic complete en bloc resection. Secondary outcomes were: clinical success, defined as tumor-free resection margins (R0 resection); full-thickness resection rate; and adverse events. RESULTS : Between July 2015 and October 2018, 367 procedures were included. Indications were difficult polyps (non-lifting sign and/or difficult location; n = 133), primary resection of suspected T1 colorectal cancer (CRC; n = 71), re-resection after incomplete resection of T1 CRC (n = 150), and subepithelial tumors (n = 13). Technical success was achieved in 308 procedures (83.9 %). In 21 procedures (5.7 %), eFTR was not performed because the lesion could not be reached or retracted into the cap. In the remaining 346 procedures, R0 resection was achieved in 285 (82.4 %) and full-thickness resection in 288 (83.2 %). The median diameter of resected specimens was 23 mm. Overall adverse event rate was 9.3 % (n = 34/367): 10 patients (2.7 %) required emergency surgery for five delayed and two immediate perforations and three cases of appendicitis. CONCLUSION : eFTR is an effective and relatively safe en bloc resection technique for complex colorectal lesions with the potential to avoid surgery. Further studies assessing the role of eFTR in early CRC treatment with long-term outcomes are needed.

Learning endoscopic resection in the esophagus.

BACKGROUND: Endoscopic resection is the cornerstone of endoscopic management of esophageal early neoplasia. However, endoscopic resection is a complex technique requiring knowledge and expertise. Our aims were to identify the most important learning points in performing endoscopic resection in a training setting and to provide information on how to improve endoscopic resection technique. METHODS: Six gastroenterologists at centers with multidisciplinary expertise in upper gastrointestinal oncology participated in a structured endoscopic resection training program, consisting of four training days with lectures and hands-on training on live pigs, further one-to-one hands-on training days, and written feedback (by an expert) on videos of unsupervised endoscopic resection procedures. The first 20 endoscopic resections of each participant were prospectively registered. Ninety learning points were independently identified by participants using a standardized questionnaire and by an expert providing written feedback on 33 unsupervised endoscopic resection videos. Three expert endoscopists selected and ranked the most important learning points in a consensus meeting. Results. The top 10 tips (illustrated by unique videos of three perforations) were: (1) allow time for inspection and use a high-definition endoscope; (2) create a preprocedural plan by placing electrocoagulation markings; (3) know the management of bleeding; (4) optimize the endoscopic view by repeatedly cleaning out stomach and target area; (5) use a therapeutic endoscope during resection; (6) always perform a test suction; (7) keep instruments close to the tip; (8) lift edges in piecemeal endoscopic cap resections; (9) know the management of perforation; (10) pin specimens down. CONCLUSIONS: This study summarized the most important learning points for performing endoscopic resection encountered during a structured endoscopic resection training program.

Simplified protocol for focal radiofrequency ablation using the HALO90 device: short-term efficacy and safety in patients with dysplastic Barrett's esophagus.

BACKGROUND AND STUDY AIMS: The standard protocol for focal radiofrequency ablation (RFA) of Barrett's esophagus comprises two applications of radiofrequency energy, cleaning of the ablated areas and catheter, and two further applications (2 × 15 J/cm(2) - cleaning - 2 × 15 J/cm(2)). A simplified protocol (3 × 15 J/cm(2), no cleaning) proved noninferior to standard protocol for individual islands of Barrett's esophagus, but may be associated with higher stenosis rates when applied circumferentially and sequentially over time. We evaluated the efficacy and safety of the above mentioned simplified protocol. PATIENTS AND METHODS: Barrett's esophagus patients undergoing focal RFA using the simplified protocol in four tertiary referral centers were retrospectively included. During each focal ablation, the gastroesophageal junction (GEJ) was ablated circumferentially in addition to Barrett's esophagus islands or tongues. Sessions continued at 8 to 12-week intervals until complete resolution of Barrett's esophagus. Primary outcome parameters comprised complete remission of dysplasia and of intestinal metaplasia, and stenosis requiring dilation. RESULTS: 83 patients with dysplastic Barrett's esophagus (median Prague classification C1M3) were enrolled; 66/83 (80 %) had endoscopic resection of a visible lesion before RFA. Intention-to-treat analysis showed complete remission of dysplasia in 78/83 (94 %) and of intestinal metaplasia in 72/83 (87 %). Stenosis requiring dilation developed in 9/83 (11 %), necessitating a median 2 dilation sessions (range 1 - 9), with ≥ 8 sessions in three patients. CONCLUSION: A treatment algorithm incorporating the simplified protocol of 3 × 15 J/cm(2), with no cleaning, for all focal RFA sessions, appears effective. The associated number and severity of stenoses, however, raises safety concerns.