Long-term behaviour of Cs-137, Cs-133 and K in beech trees of French forests

In the long-term after atmospheric deposit onto a forest ecosystem, Cs-137 becomes incorporated into the biogeochemical cycle of stable elements and progressively reaches a quasi-equilibrium state. This study aimed at determining to what extent Cs-137 activity distribution in tree vegetation could be predicted from that of stable caesium (Cs-133) and potassium (K), which are known to be stable chemical analogues and competitors for Cs-137 intake in tree organs. Field campaigns that focused on beech trees (Fagus sylvatica L.) were conducted in 2021 in three French forest stands with contrasted characteristics regarding either the contribution of global vs. Chornobyl fallouts, soil or climatic conditions. Decades after Cs-137 fallouts, it was found that more than 80% of the total radioactive inventory in the system remained confined in the top 20 cm mineral layers, while organic layers and beech vegetation (including roots) contributed each to less than 1.5%. The enhanced downward migration of Cs-137 in cambisol than podzol forest sites was presumably due to migration of clay particles and bioturbation. The distribution of Cs-137 and Cs-133 inventories in beech trees was very similar among sites but differed from that of K due a higher accumulation of Cs isotopes in roots (40-50% vs. < 25% for K). The aggregated transfer factor (Tag) of Cs-137 calculated for aerial beech organs were all lower than those reported in literature more than 20 years ago, this suggesting a decrease of bioavailability in soil due to ageing processes. Regarding their variability, Tags were generally lower by a factor 5 at the cambisol site, which was fairly well explained by a much higher value of RIP (radiocesium immobilisation potential). Cs-137 concentrations in trees organs normalized by the soil exchangeable fractions were linearly correlated to those of Cs-133 and the best fit was found for the linear regression model without intercept indicating that no more contribution of the foliar uptake could be observed on long term. Provided that the vertical distribution of caesium concentrations and fine root density are properly measured or estimated, Cs-133 was shown to be a much better proxy than K to estimate the root transfer of Cs-137.

Influence of artificial intelligence on the diagnostic performance of endoscopists in the assessment of Barrett's esophagus: a tandem randomized and video trial

BACKGROUND

This study evaluated the effect of an artificial intelligence (AI)-based clinical decision support system on the performance and diagnostic confidence of endoscopists in their assessment of Barrett's esophagus (BE).

METHODS

96 standardized endoscopy videos were assessed by 22 endoscopists with varying degrees of BE experience from 12 centers. Assessment was randomized into two video sets: group A (review first without AI and second with AI) and group B (review first with AI and second without AI). Endoscopists were required to evaluate each video for the presence of Barrett's esophagus-related neoplasia (BERN) and then decide on a spot for a targeted biopsy. After the second assessment, they were allowed to change their clinical decision and confidence level.

RESULTS

AI had a stand-alone sensitivity, specificity, and accuracy of 92.2%, 68.9%, and 81.3%, respectively. Without AI, BE experts had an overall sensitivity, specificity, and accuracy of 83.3%, 58.1%, and 71.5%, respectively. With AI, BE nonexperts showed a significant improvement in sensitivity and specificity when videos were assessed a second time with AI (sensitivity 69.8% [95%CI 65.2%-74.2%] to 78.0% [95%CI 74.0%-82.0%]; specificity 67.3% [95%CI 62.5%-72.2%] to 72.7% [95%CI 68.2%-77.3%]). In addition, the diagnostic confidence of BE nonexperts improved significantly with AI.

CONCLUSION

BE nonexperts benefitted significantly from additional AI. BE experts and nonexperts remained significantly below the stand-alone performance of AI, suggesting that there may be other factors influencing endoscopists' decisions to follow or discard AI advice.

First report from the International Evaluation of Endoscopic classification Japan NBI Expert Team: International multicenter web trial

OBJECTIVES

Narrow-band imaging (NBI) contributes to real-time optical diagnosis and classification of colorectal lesions. The Japan NBI Expert Team (JNET) was introduced in 2011. The aim of this study was to explore the diagnostic accuracy of JNET when applied by European and Japanese endoscopists not familiar with this classification.

METHODS

This study was conducted by 36 European Society of Gastrointestinal Endoscopy (ESGE) and 49 Japan Gastroenterological Endoscopy Society (JGES) non-JNET endoscopists using still images of 150 lesions. For each lesion, nonmagnified white-light, nonmagnified NBI, and magnified NBI images were presented. In the magnified NBI, the evaluation area was designated by region of interest (ROI). The endoscopists scored histological prediction for each lesion.

RESULTS

In ESGE members, the sensitivity, specificity, and accuracy were respectively 73.3%, 94.7%, and 93.0% for JNET Type 1; 53.0%, 64.9%, and 62.1% for Type 2A; 43.9%, 67.7%, and 55.1% for Type 2B; and 38.1%, 93.7%, and 85.1% for Type 3. When Type 2B and 3 were considered as one category of cancer, the sensitivity, specificity, and accuracy for differentiating high-grade dysplasia and cancer from the others were 59.9%, 72.5%, and 63.8%, respectively. These trends were the same for JGES endoscopists.

CONCLUSION

The diagnostic accuracy of the JNET classification was similar between ESGE and JGES and considered to be sufficient for JNET Type 1. On the other hand, the accuracy for Types 2 and 3 is not sufficient; however, JNET 2B lesions should be resected en bloc due to the risk of cancers and JNET 3 can be treated by surgery due to its high specificity.

[Acute abdomen-Rare cause in an 80-year-old female patient under immunosuppressive treatment]

An 80-year-old woman presented to the emergency department due to abdominal pain. She had a history of opportunistic pneumonia under the effects of immunosuppression after the diagnosis of autoimmune hepatitis. The imaging showed an omental cake formation and the suspicion of peritoneal carcinomatosis. The patient developed an acute abdomen during the hospital stay, followed by exploratory laparotomy. In the presence of extensive intra-abdominal abscess formation both surgically acquired material and blood culture revealed disseminated nocardiosis. The course was fatal due to fulminant septic shock.

Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2024

1:  ESGE recommends cold snare polypectomy (CSP), to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of diminutive polyps (≤ 5 mm).Strong recommendation, high quality of evidence. 2:  ESGE recommends against the use of cold biopsy forceps excision because of its high rate of incomplete resection.Strong recommendation, moderate quality of evidence. 3:  ESGE recommends CSP, to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of small polyps (6-9 mm).Strong recommendation, high quality of evidence. 4:  ESGE recommends hot snare polypectomy for the removal of nonpedunculated adenomatous polyps of 10-19 mm in size.Strong recommendation, high quality of evidence. 5:  ESGE recommends conventional (diathermy-based) endoscopic mucosal resection (EMR) for large (≥ 20 mm) nonpedunculated adenomatous polyps (LNPCPs).Strong recommendation, high quality of evidence. 6:  ESGE suggests that underwater EMR can be considered an alternative to conventional hot EMR for the treatment of adenomatous LNPCPs.Weak recommendation, moderate quality of evidence. 7:  Endoscopic submucosal dissection (ESD) may also be suggested as an alternative for removal of LNPCPs of ≥ 20 mm in selected cases and in high-volume centers.Weak recommendation, low quality evidence. 8:  ESGE recommends that, after piecemeal EMR of LNPCPs by hot snare, the resection margins should be treated by thermal ablation using snare-tip soft coagulation to prevent adenoma recurrence.Strong recommendation, high quality of evidence. 9:  ESGE recommends (piecemeal) cold snare polypectomy or cold EMR for SSLs of all sizes without suspected dysplasia.Strong recommendation, moderate quality of evidence. 10:  ESGE recommends prophylactic endoscopic clip closure of the mucosal defect after EMR of LNPCPs in the right colon to reduce to reduce the risk of delayed bleeding.Strong recommendation, high quality of evidence. 11:  ESGE recommends that en bloc resection techniques, such as en bloc EMR, ESD, endoscopic intermuscular dissection, endoscopic full-thickness resection, or surgery should be the techniques of choice in cases with suspected superficial invasive carcinoma, which otherwise cannot be removed en bloc by standard polypectomy or EMR.Strong recommendation, moderate quality of evidence.

Western outcomes of circumferential endoscopic submucosal dissection for early esophageal squamous cell carcinoma

BACKGROUND AND AIMS

Circumferential endoscopic submucosal dissection (cESD) in the esophagus has been reported to be feasible in small Eastern case series. We assessed the outcomes of cESD in the treatment of early esophageal squamous cell carcinoma (ESCC) in Western countries.

METHODS

We conducted an international study at 25 referral centers in Europe and Australia using prospective databases. We included all patients with ESCC treated with cESD before November 2022. Our main outcomes were curative resection according to European guidelines and adverse events.

RESULTS

A total of 171 cESDs were performed on 165 patients. En bloc and R0 resections rates were 98.2% (95% confidence interval [CI], 95.0-99.4) and 69.6% (95% CI, 62.3-76.0), respectively. Curative resection was achieved in 49.1% (95% CI, 41.7-56.6) of the lesions. The most common reason for noncurative resection was deep submucosal invasion (21.6%). The risk of stricture requiring 6 or more dilations or additional techniques (incisional therapy/stent) was high (71%), despite the use of prophylactic measures in 93% of the procedures. The rates of intraprocedural perforation, delayed bleeding, and adverse cardiorespiratory events were 4.1%, 0.6%, and 4.7%, respectively. Two patients died (1.2%) of a cESD-related adverse event. Overall and disease-free survival rates at 2 years were 91% and 79%.

CONCLUSIONS

In Western referral centers, cESD for ESCC is curative in approximately half of the lesions. It can be considered a feasible treatment in selected patients. Our results suggest the need to improve patient selection and to develop more effective therapies to prevent esophageal strictures.

Stroma AReactive Invasion Front Areas (SARIFA) proves prognostic relevance in gastric carcinoma and is based on a tumor-adipocyte interaction indicating an altered immune response

BACKGROUND

Recently, we presented Stroma AReactive Invasion Front Areas (SARIFA) as a new histomorphologic negative prognostic biomarker in gastric cancer. It is defined as direct contact between tumor cells and fat cells. The aim of this study was to further elucidate the underlying genomic, transcriptional, and immunological mechanisms of the SARIFA phenomenon.

METHODS

To address these questions, SARIFA was classified on H&E-stained tissue sections of three cohorts: an external cohort (n = 489, prognostic validation), the TCGA-STAD cohort (n = 194, genomic and transcriptomic analysis), and a local cohort (n = 60, digital spatial profiling (whole transcriptome) and double RNA in situ hybridization/immunostaining of cytokines).

RESULTS

SARIFA status proved to be an independent negative prognostic factor for overall survival in an external cohort of gastric carcinomas. In TCGA-STAD cohort, SARIFA is not driven by distinct genomic alterations, whereas the gene expression analyses showed an upregulation of FABP4 in SARIFA-positive tumors. In addition, the transcriptional regulations of white adipocyte differentiation, triglyceride metabolism, and catabolism were upregulated in pathway analyses. In the DSP analysis of SARIFA-positive tumors, FABP4 and the transcriptional regulation of white adipocyte differentiation were upregulated in macrophages. Additionally, a significantly lower expression of the cytokines IL6 and TNFα was observed at the invasion front.

CONCLUSIONS

SARIFA proves to be a strong negative prognostic biomarker in advanced gastric cancer, implicating an interaction of tumor cells with tumor-promoting adipocytes with crucial changes in tumor cell metabolism. SARIFA is not driven by tumor genetics but is very likely driven by an altered immune response as a causative mechanism.

Evaluation of a single-use gastroscope in patients presenting with suspected upper gastrointestinal hemorrhage: a pilot feasibility study (One-Scope I)

BACKGROUND : Outbreaks of multidrug-resistant bacteria due to contaminated duodenoscopes and infection risks during the COVID-19 pandemic have driven the development of single-use endoscopes. The first single-use gastroscope is now available in Europe. Besides waste disposal and cost issues, the infection risk and performance remain unclear. We aimed to evaluate a single-use gastroscope in patients with signs of upper gastrointestinal bleeding. METHODS : 20 consecutive patients presenting with clinical signs of upper gastrointestinal bleeding between October and November 2022 were included in this case series. The primary aim was technical success, defined as access to the descending duodenum and adequate assessment of the upper gastrointestinal tract for the presence of a bleeding site. RESULTS : The primary aim was achieved in 19/20 patients (95 %). The bleeding site was identified in 18 patients. A therapeutic intervention was performed in six patients (two cap-mounted clips, one standard hemostatic clip, two variceal band ligations, one hemostatic powder, two adrenaline injections); technical and clinical success were achieved in all six patients. Two crossovers to a standard gastroscope occurred. CONCLUSIONS : Use of single-use gastroscopes may be feasible for patients presenting for urgent endoscopic evaluation and treatment of upper gastrointestinal bleeding.

Wide-area transepithelial sampling with computer-assisted analysis to detect high grade dysplasia and cancer in Barrett's esophagus: a multicenter randomized study

BACKGROUND

Current surveillance for Barrett's esophagus (BE), consisting of four-quadrant random forceps biopsies (FBs), has an inherent risk of sampling error. Wide-area transepithelial sampling (WATS) may increase detection of high grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). In this multicenter randomized trial, we aimed to evaluate WATS as a substitute for FB.

METHODS

Patients with known BE and a recent history of dysplasia, without visible lesions, at 17 hospitals were randomized to receive either WATS followed by FB or vice versa. All WATS samples were examined, with computer assistance, by at least two experienced pathologists at the CDx Diagnostics laboratory. Similarly, all FBs were examined by two expert pathologists. The primary end point was concordance/discordance for detection of HGD/EAC between the two techniques.

RESULTS

172 patients were included, of whom 21 had HGD/EAC detected by both modalities, 18 had HGD/EAC detected by WATS but missed by FB, and 12 were detected by FB but missed by WATS. The detection rate of HGD/EAC did not differ between WATS and FB (P = 0.36). Using WATS as an adjunct to FB significantly increased the detection of HGD/EAC vs. FB alone (absolute increase 10 % [95 %CI 6 % to 16 %]). Mean procedural times in minutes for FB alone, WATS alone, and the combination were 6.6 (95 %CI 5.9 to 7.1), 4.9 (95 %CI 4.1 to 5.4), and 11.2 (95 %CI 10.5 to 14.0), respectively.

CONCLUSIONS

Although the combination of WATS and FB increases dysplasia detection in a population of BE patients enriched for dysplasia, we did not find a statistically significant difference between WATS and FB for the detection of HGD/EAC as single modality.

Detection of duodenal villous atrophy on endoscopic images using a deep learning algorithm

BACKGROUND AND AIMS

Celiac disease with its endoscopic manifestation of villous atrophy (VA) is underdiagnosed worldwide. The application of artificial intelligence (AI) for the macroscopic detection of VA at routine EGD may improve diagnostic performance.

METHODS

A dataset of 858 endoscopic images of 182 patients with VA and 846 images from 323 patients with normal duodenal mucosa was collected and used to train a ResNet18 deep learning model to detect VA. An external dataset was used to test the algorithm, in addition to 6 fellows and 4 board-certified gastroenterologists. Fellows could consult the AI algorithm's result during the test. From their consultation distribution, a stratification of test images into "easy" and "difficult" was performed and used for classified performance measurement.

RESULTS

External validation of the AI algorithm yielded values of 90%, 76%, and 84% for sensitivity, specificity, and accuracy, respectively. Fellows scored corresponding values of 63%, 72%, and 67% and experts scored 72%, 69%, and 71%, respectively. AI consultation significantly improved all trainee performance statistics. Although fellows and experts showed significantly lower performance for difficult images, the performance of the AI algorithm was stable.

CONCLUSIONS

In this study, an AI algorithm outperformed endoscopy fellows and experts in the detection of VA on endoscopic still images. AI decision support significantly improved the performance of nonexpert endoscopists. The stable performance on difficult images suggests a further positive add-on effect in challenging cases.

Endoscopic submucosal dissection for superficial esophageal squamous cell carcinoma: long-term follow-up in a Western center

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD) has been established as a treatment modality for superficial esophageal squamous cell carcinoma (ESCC). Long-term follow-up data are lacking in Western countries. The aim of this study was to analyze long-term survival in a Western center.

METHODS

Patients undergoing ESD for ESCC were included. The analysis was performed retrospectively using a prospectively collected database.

RESULTS

R0 resection rate was 96.7% (59/61 lesions in 58 patients). Twenty-seven patients (46.6%) fulfilled the curative resection criteria (M1/M2) (group A), 11 patients (19.0%) had M3 lesions without lymphovascular invasion (LVI) (group B), and 20 patients (34.5%) had lesions with submucosal invasion or LVI (group C). Additional treatment was recommended after non-curative resection. It was not performed in 20/31 patients (64.5%), mainly because of comorbidities (75%). Twenty-nine out of 58 (50.0%) patients died during a mean follow-up of 3.7 years. Death was related to ESCC in 17.2% (5/29) of patients. The disease-specific survival rate after curative resection was 100%. Overall survival rates after 5 years were 61.5%, 63.6% and 28.1% for groups A, B, and C, respectively. The overall survival was significantly worse after non-curative resection (p=0.038).

CONCLUSION

Non-curative resection is frequent after ESD for ESCC in Western patients. The long-term prognosis is limited and mainly determined by comorbidity. Early diagnosis and pre-interventional assessments need to be improved.

Vessel and tissue recognition during third-space endoscopy using a deep learning algorithm

In this study, we aimed to develop an artificial intelligence clinical decision support solution to mitigate operator-dependent limitations during complex endoscopic procedures such as endoscopic submucosal dissection and peroral endoscopic myotomy, for example, bleeding and perforation. A DeepLabv3-based model was trained to delineate vessels, tissue structures and instruments on endoscopic still images from such procedures. The mean cross-validated Intersection over Union and Dice Score were 63% and 76%, respectively. Applied to standardised video clips from third-space endoscopic procedures, the algorithm showed a mean vessel detection rate of 85% with a false-positive rate of 0.75/min. These performance statistics suggest a potential clinical benefit for procedure safety, time and also training.

Quantitative analysis of submucosal excision depth in endoscopic resection for early Barrett's cancer

BACKGROUND : Following endoscopic resection of early-stage Barrett's esophageal adenocarcinoma (BEA), further oncologic management then fundamentally relies upon the accurate assessment of histopathologic risk criteria, which requires there to be sufficient amounts of submucosal tissue in the resection specimens. METHODS : In 1685 digitized tissue sections from endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) performed for 76 early BEA cases from three experienced centers, the submucosal thickness was determined, using software developed in-house. Neoplastic lesions were manually annotated. RESULTS : No submucosa was seen in about a third of the entire resection area (mean 33.8 % [SD 17.2 %]), as well as underneath cancers (33.3 % [28.3 %]), with similar results for both resection methods and with respect to submucosal thickness. ESD results showed a greater variability between centers than EMR. In T1b cancers, a higher rate of submucosal defects tended to correlate with R1 resections. CONCLUSION : The absence of submucosa underneath about one third of the tissue of endoscopically resected BEAs should be improved. Results were more center-dependent for ESD than for EMR. Submucosal defects can potentially serve as a parameter for standardized reports.

Modified endoscopic mucosal resection techniques for treating precancerous colorectal lesions

Endoscopic mucosal resection (EMR) is a technique allowing efficacious and minimally invasive resection of precancerous lesions across the entire gastrointestinal tract. However, conventional EMR, involving injection of fluid into the submucosal space, is imperfect, given the high rate of recurrence of post-endoscopic resection adenoma, especially after piecemeal resection. In light of these observations, modifications of the technique have been proposed to overcome the weakness of conventional EMR. Some of them were designed to maximize the chance of en bloc resection—cap-assisted EMR, underwater EMR, tip-in EMR, precutting, assisted by ligation device—while others were designed to minimize the complications (cold EMR). In this review, we present their modes of action and summarize the evidence regarding their efficacy and safety.

Underwater vs Conventional Endoscopic Mucosal Resection of Large Sessile or Flat Colorectal Polyps: A Prospective Randomized Controlled Trial

BACKGROUND & AIMS

Conventional endoscopic mucosal resection (CEMR) with submucosal injection is the current standard for the resection of large, nonmalignant colorectal polyps. We investigated whether underwater endoscopic mucosal resection (UEMR) is superior to CEMR for large (20-40mm) sessile or flat colorectal polyps.

METHODS

In this prospective randomized controlled study, patients with sessile or flat colorectal polyps between 20 and 40 mm in size were randomly assigned to UEMR or CEMR. The primary outcome was the recurrence rate after 6 months. Secondary outcomes included en bloc and R0 resection rates, number of resected pieces, procedure time, and adverse events.

RESULTS

En bloc resection rates were 33.3% in the UEMR group and 18.4% in the CEMR group (P = .045); R0 resection rates were 32.1% and 15.8% for UEMR vs CEMR, respectively (P = .025). UEMR was performed with significantly fewer pieces compared to CEMR (2 pieces: 45.5% UEMR vs 17.7% CEMR; P = .001). The overall recurrence rate did not differ between both groups (P = .253); however, subgroup analysis showed a significant difference in favor of UEMR for lesions of >30 mm to ≤40 mm in size (P = .031). The resection time was significantly shorter in the UEMR group (8 vs 14 minutes; P < .001). Adverse events did not differ between both groups (P = .611).

CONCLUSIONS

UEMR is superior to CEMR regarding en bloc resection, R0 resection, and procedure time for large colorectal lesions and shows significantly lower recurrence rates for lesions >30 mm to ≤40 mm in size. UEMR should be considered for the endoscopic resection of large colorectal polyps.

Semiautomatic analysis of tumor proportion in colon cancer: Lessons from a validation study

The tumor stroma ratio (TSR) is a promising histopathologic prognostic biomarker, which could allow for more accurate risk stratification and improved patient management in colorectal cancer. The purpose of our research was to validate the results of a previous study, which had suggested that not only a low but also a high tumor proportion (TP) might be an independent risk factor for occurrence of distant metastasis and worse overall survival using a semiautomatic image analysis approach with the open-source software ImageJ. We investigated 253 pT3 and pT4 adenocarcinomas of no special type. The previously established thresholds (PES-cut-offs) used to classify the patients (previous 3-tiered-classification) according to the tumor proportion (TP) in a highTP (TP ≥ 54%), a mediumTP (TP < 54% ∩ TP >15%) and a lowTP (TP ≤ 15%) group did not show a significant risk stratification. Even the adjustment of these threshold revealed no significant results. Therefore, a receiver-operating characteristic (ROC) analysis was performed to establish the cut-off with the most significant predictive power and a "new 2-tiered-classification" using this cut-off (40% at MinTP) showed a significantly shorter absence of metastasis for patients with a low TP (p = 0.007). These results confirm that a low TP is associated with an adverse prognosis. This study did not confirm the previous assumption that a high TP might also be a risk factor for occurrence of metastasis. Furthermore, it demonstrates that this semiautomatic technique is not superior to the established method, so that approaches to enhance prognostic techniques should continue.

Endoscopic Submucosal Dissection in Europe: Results of 1000 Neoplastic Lesions From the German Endoscopic Submucosal Dissection Registry

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) enables the curative resection of early malignant lesions and is associated with reduced recurrence risk. Due to the lack of comprehensive ESD data in the West, the German ESD registry was set up to evaluate relevant outcomes of ESD.

METHODS

The German ESD registry is a prospective uncontrolled multicenter study. During a 35-month period, 20 centers included 1000 ESDs of neoplastic lesions. The results were evaluated in terms of en bloc, R0, curative resection rates, and recurrence rate after a 3-month and 12-month follow-up. Additionally, participating centers were grouped into low-volume (≤20 ESDs/y), middle-volume (20-50/y), and high-volume centers (>50/y). A multivariate analysis investigating risk factors for noncurative resection was performed.

RESULTS

Overall, en bloc, R0, and curative resection rates of 92.4% (95% confidence interval [CI], 0.90-0.94), 78.8% (95% CI, 0.76-0.81), and 72.3% (95% CI, 0.69-0.75) were achieved, respectively. The overall complication rate was 8.3% (95% CI, 0.067-0.102), whereas the recurrence rate after 12 months was 2.1%. High-volume centers had significantly higher en bloc, R0, curative resection rates, and recurrence rates and lower complication rates than middle- or low-volume centers. The lesion size, hybrid ESD, age, stage T1b carcinoma, and treatment outside high-volume centers were identified as risk factors for noncurative ESD.

CONCLUSION

In Germany, ESD achieves excellent en bloc resection rates but only modest curative resection rates. ESD requires a high level of expertise, and results vary significantly depending on the center's yearly case volume.

Stroma AReactive Invasion Front Areas (SARIFA) - a new prognostic biomarker in gastric cancer related to tumor-promoting adipocytes

Compared to other malignancies, there is a lack of easy-to-evaluate biomarkers for gastric cancer, which is associated with an adverse clinical outcome in many cases. Here, we present Stroma AReactive Invasion Front Areas (SARIFA) as a new histological prognostic marker. We defined SARIFA as the direct contact between a cluster of tumor glands/cells comprising at least five tumor cells and inconspicuous surrounding adipose tissue at the invasion front. A total of 480 adenocarcinomas of the stomach and the gastroesophageal junction from two different collections were classified according to SARIFA. To understand the potential underlying mechanisms, a transcriptome analysis was conducted using digital spatial profiling (DSP). It was found that 20% of the tumors were SARIFA-positive. Kappa values between the three pathologists were good in both collections: 0.74 and 0.78. Patients who presented SARIFA-positive tumors had a significantly lower overall survival in Collections A (median: 20.0 versus 44.0 months; p = 0.014, n = 160) and B (median: 15.0 versus 41.0 months; p < 0.0001, n = 320). SARIFA positivity emerged as a negative independent prognostic factor for overall survival (HR 1.638, 95% CI 1.153-2.326, p = 0.006). Using DSP, the most upregulated genes in SARIFA-positive cases were those associated with triglyceride catabolism and endogenous sterols. COL15A1, FABP2, and FABP4 were differentially expressed in positive cases. At the protein level, the expression of proteins related to lipid metabolism was confirmed. SARIFA combines low inter-observer variability, minimal effort, and high prognostic relevance, and is therefore an extremely promising biomarker related to tumor-promoting adipocytes in gastric cancer. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Endoscopic prediction of submucosal invasion in Barrett's cancer with the use of artificial intelligence: a pilot study

BACKGROUND

The accurate differentiation between T1a and T1b Barrett's-related cancer has both therapeutic and prognostic implications but is challenging even for experienced physicians. We trained an artificial intelligence (AI) system on the basis of deep artificial neural networks (deep learning) to differentiate between T1a and T1b Barrett's cancer on white-light images.

METHODS

Endoscopic images from three tertiary care centers in Germany were collected retrospectively. A deep learning system was trained and tested using the principles of cross validation. A total of 230 white-light endoscopic images (108 T1a and 122 T1b) were evaluated using the AI system. For comparison, the images were also classified by experts specialized in endoscopic diagnosis and treatment of Barrett's cancer.

RESULTS

The sensitivity, specificity, F1 score, and accuracy of the AI system in the differentiation between T1a and T1b cancer lesions was 0.77, 0.64, 0.74, and 0.71, respectively. There was no statistically significant difference between the performance of the AI system and that of experts, who showed sensitivity, specificity, F1, and accuracy of 0.63, 0.78, 0.67, and 0.70, respectively.

CONCLUSION

This pilot study demonstrates the first multicenter application of an AI-based system in the prediction of submucosal invasion in endoscopic images of Barrett's cancer. AI scored equally to international experts in the field, but more work is necessary to improve the system and apply it to video sequences and real-life settings. Nevertheless, the correct prediction of submucosal invasion in Barrett's cancer remains challenging for both experts and AI.

Endoscopic full-thickness resection and its treatment alternatives in difficult-to-treat lesions of the lower gastrointestinal tract: a cost-effectiveness analysis

Objective

Endoscopic full-thickness resection (EFTR) has shown efficacy and safety in the colorectum. The aim of this analysis was to investigate whether EFTR is cost-effective in comparison with surgical and endoscopic treatment alternatives.

Design

Real data from the study cohort of the prospective, single-arm WALL RESECT study were used. A simulated comparison arm was created based on a survey that included suggested treatment alternatives to EFTR of the respective lesions. Treatment costs and reimbursement were calculated in euro according to the coding rules of 2017 and 2019 (EFTR). R0 resection rate was used as a measure of effectiveness. To assess cost-effectiveness, the average cost-effectiveness ratio (ACER) and the incremental cost-effectiveness ratio (ICER) were determined. Calculations were made both from the perspective of the care provider as well as of the payer.

Results

The cost per case was €2852.20 for the EFTR group, €1712 for the standard endoscopic resection (SER) group, €8895 for the surgical resection group and €5828 for the pooled alternative treatment to EFTR. From the perspective of the care provider, the ACER (mean cost per R0 resection) was €3708.98 for EFTR, €3115.10 for SER, €8924.05 for surgical treatment and €7169.30 for all pooled and weighted alternatives to EFTR. The ICER (additional cost per R0 resection compared with EFTR) was €5196.47 for SER, €26 533.13 for surgical resection and €67 768.62 for the pooled rate of alternatives. Results from the perspective of the payer were similar.

Conclusion

EFTR is cost-effective in comparison with surgical and endoscopic treatment alternatives in the colorectum.

Convolutional Neural Networks for the evaluation of cancer in Barrett's esophagus: Explainable AI to lighten up the black-box

Even though artificial intelligence and machine learning have demonstrated remarkable performances in medical image computing, their level of accountability and transparency must be provided in such evaluations. The reliability related to machine learning predictions must be explained and interpreted, especially if diagnosis support is addressed. For this task, the black-box nature of deep learning techniques must be lightened up to transfer its promising results into clinical practice. Hence, we aim to investigate the use of explainable artificial intelligence techniques to quantitatively highlight discriminative regions during the classification of early-cancerous tissues in Barrett's esophagus-diagnosed patients. Four Convolutional Neural Network models (AlexNet, SqueezeNet, ResNet50, and VGG16) were analyzed using five different interpretation techniques (saliency, guided backpropagation, integrated gradients, input × gradients, and DeepLIFT) to compare their agreement with experts' previous annotations of cancerous tissue. We could show that saliency attributes match best with the manual experts' delineations. Moreover, there is moderate to high correlation between the sensitivity of a model and the human-and-computer agreement. The results also lightened that the higher the model's sensitivity, the stronger the correlation of human and computational segmentation agreement. We observed a relevant relation between computational learning and experts' insights, demonstrating how human knowledge may influence the correct computational learning.

Influence of ponds on hazardous metal distribution in sediments at a catchment scale (agricultural critical zone, S-W France)

Eight potentially toxic trace elements were investigated together with the physicochemical characteristics of sediments collected upstream, downstream, and from various ponds from three adjacent carbonated agricultural catchments in southwestern France. Geochemical indices with local references and multivariate data analysis revealed a significant enrichment of Cd, followed by Ni and Cu in sediments, originating from agricultural practices, especially in the upper catchments sensitive to erosion processes. Five other PTEs (As, Pb, Co, Cr, and Zn) mostly originated from the weathering process of the molasse. Clay minerals and/or iron oxides were the main controlling factors for most PTEs. In ponds, Cd was regulated by Ca co-precipitation favoured by the long hydraulic retention time and increased pH, whereas it was mostly controlled by silicates in stream sediments. Copper, Pb, and Cd were the highly extractable metals, suggesting the risk of a hazardous environment. Multivariate analysis revealed that several environmental factors affected the spatial variation of PTE concentrations in sediments as well as the trapping role of ponds (texture, slope, soil erosion, pond size and position, discharge, hydraulic retention time) in this area of intensive agricultural practices. Our conclusions are useful for pond management in a context of increasing water demand and climate warming.

Gastric cancer- endoscopic treatment of early lesions, the West learns from the East

Gastric cancer still has one of the highest incidence rates worldwide. Screening programs have been established in high incidence regions, especially in Asia, but in the West, screening for gastric cancer is not generally recommended. Gastroscopy is the gold standard for diagnosing gastric cancer. For the treatment of early gastric cancer, endoscopic resection is the method of choice. With the ESD technique, larger lesions can be resected en-bloc. Guideline and extended guideline criteria for the choice of lesions for ESD have been evaluated extensively, initially in Asia and later in the West as well. For lesions which are out of indication, a surgical approach must be recommended. To detect early recurrence or metachronous lesions, follow-up should be performed after ER.

[Mesothelial proliferation of the tunica vaginalis testis]

Proliferative changes seen in reactive mesothelial hyperplasia of a hydrocele sac may mimic malignant mesothelioma. There is no immunohistochemical staining that reliably separates benign from malignant mesothelial proliferations. However, the combined analysis of BAP1 by immunohistochemistry and CDKN2A by FISH has been reported to yield both a high specificity and sensitivity in this differential diagnosis. In addition, the evaluation of risk factors such as asbestos exposure or prior traumata may be helpful for the correct diagnosis. Exclusion of stromal invasion, which is diagnostic for malign mesothelioma, is of utmost importance. Therefore, extended histological workup is essential.

Assisting Barrett's esophagus identification using endoscopic data augmentation based on Generative Adversarial Networks

Barrett's esophagus figured a swift rise in the number of cases in the past years. Although traditional diagnosis methods offered a vital role in early-stage treatment, they are generally time- and resource-consuming. In this context, computer-aided approaches for automatic diagnosis emerged in the literature since early detection is intrinsically related to remission probabilities. However, they still suffer from drawbacks because of the lack of available data for machine learning purposes, thus implying reduced recognition rates. This work introduces Generative Adversarial Networks to generate high-quality endoscopic images, thereby identifying Barrett's esophagus and adenocarcinoma more precisely. Further, Convolution Neural Networks are used for feature extraction and classification purposes. The proposed approach is validated over two datasets of endoscopic images, with the experiments conducted over the full and patch-split images. The application of Deep Convolutional Generative Adversarial Networks for the data augmentation step and LeNet-5 and AlexNet for the classification step allowed us to validate the proposed methodology over an extensive set of datasets (based on original and augmented sets), reaching results of 90% of accuracy for the patch-based approach and 85% for the image-based approach. Both results are based on augmented datasets and are statistically different from the ones obtained in the original datasets of the same kind. Moreover, the impact of data augmentation was evaluated in the context of image description and classification, and the results obtained using synthetic images outperformed the ones over the original datasets, as well as other recent approaches from the literature. Such results suggest promising insights related to the importance of proper data for the accurate classification concerning computer-assisted Barrett's esophagus and adenocarcinoma detection.

Complication risk despite preventive endoscopic measures in patients undergoing endoscopic mucosal resection of large duodenal adenomas

BACKGROUND : Endoscopic mucosal resection (EMR) is the standard treatment of ampullary and nonampullary duodenal adenomas. EMR of large (10-29 mm) and giant (≥ 30 mm) lesions carries a risk of complications such as delayed bleeding and perforation. Prospective data on duodenal EMR are scarce. This study aimed to evaluate the efficacy of endoscopic procedures (clipping and coagulation of visible vessels) to prevent complications after EMR of large and giant lesions. METHODS : 110 patients with 118 adenomas (29 ampullary and 89 nonampullary) were included prospectively. RESULTS : 15 lesions were small (12.7 %), 68 were large (57.6 %), and 35 were giant (29.7 %). Endoscopic prevention of delayed complications was performed in 81.4 % (n = 96) of all lesions and 94.3 % (n = 33) of giant lesions. Complete resection was achieved in 111 lesions (94.1 %). Complications were 22 delayed bleedings (18.6 %), 3 intraprocedural perforations (2.5 %), 2 delayed perforations (1.7 %), and 1 stricture (0.8 %). Major complications were associated with lesions size ≥ 30 mm (28.6 % vs. 9.6 %; P = 0.02) and ampullary adenomas (27.6 % vs. 11.2 %; P = 0.07). All minor bleeding and 75 % of major bleeding episodes were treated endoscopically; 25 % of major bleedings needed radiologic embolization. Two fatal courses were observed when delayed perforation occurred after EMR of giant lesions. Residual adenoma was detected in 20.4 % at first follow-up. CONCLUSIONS : EMR of giant duodenal neoplasia carries a substantial risk of major complications and recurrences. Resection technique and prevention of delayed complications need to be improved. Further measures should be evaluated in randomized studies.

Double-endoscope assisted endoscopic submucosal dissection for treating tumors in rectum and distal colon by expert endoscopists: a feasibility study

Background

Colorectal endoscopic submucosal dissection (ESD) is an effective but challenging procedure. To facilitate ESD, several methods that apply traction are available; however, the optimal one remains to be established. The aim of this study was to evaluate the feasibility and safety of the double-endoscope assisted ESD (DEA-ESD) by improving traction to treat complex colorectal lesions.

Methods

Naïve or previously treated lesions in the rectum and sigmoid colon were included. A grasping forceps advanced through a small-caliber endoscope (GIF-XP190N, Olympus Medical Systems, Tokyo, Japan, 5.4 mm outer diameter) was used to apply traction to the mucosal flap. Lesions were deemed complex when they exceeded a total of nine points on the SMSA scoring system (size, morphology, site, and access) and recurrent when they were previously treated with endoscopic mucosal resection (EMR). Outcome measures included procedural success, total procedure time, complications, and recurrence rate at 3-month follow-up.

Results

Nine patients (mean age 62.3 ± 14.5 years) were included; five had rectal and four had tumors in the sigmoid colon. The median SMSA score was 14 (SMSA Level IV—complex polyp), while three patients were pre-treated with EMR. DEA-ESD was technically feasible in all cases. En bloc resection and R0 resection rates were 100%, respectively, with a mean procedure time of 128.4 ± 54.1 min. No immediate or delayed complications occurred.

Conclusions

DEA-ESD is a feasible and safe method for treating complex or recurrent tumors in the rectum and distal colon.

Electronic supplementary material

The online version of this article (10.1007/s10151-020-02308-4) contains supplementary material, which is available to authorized users.

[Screening gastroscopy in Germany - first results of the pilot phase of the Prä-GIT study]

The primary aim of the Prä-GIT study is to collect information on the prevalence and course of precancerous and early malignant lesions in the upper GIT (uGIT) as well as risk factors associated with these lesions in asymptomatic individuals. Study participants presenting for a screening colonoscopy will undergo an additional endoscopic examination of the uGIT in the same session. 5000 participants in 30 endoscopy clinics in Bayern will be included. The pilot study presented here was performed to test the main study protocol as well as the acceptance of an additional uGIT endoscopic examination.

METHODS

 Three endoscopy clinics in Bayern took part in the three-month pilot study between October and December 2018. Patients presenting for a screening colonoscopy in these clinics were offered an additional endoscopic examination of the uGIT which was performed according to a standard operating procedure (SOP). Furthermore, data on dietary habits and lifestyle, as well as biological samples, were collected.

RESULTS

 52 participants were included in three clinics in Altötting, Augsburg and Regensburg. The average age was 63.4 years. The average time spent per uGIT endoscopy was 11 minutes. No complications occurred. One participant showed a polyp of the recessus piriformis. Refluxesophagitis was seen in 21 participants, four participants had Barrett's esophagus with histological evidence of low-grade dysplasia in one patient, and an esophageal polyp with low-grade dysplasia was seen in one participant. Helicobacter-pylori gastritis was documented in 12 participants. Corpus-dominant atrophy was described in one participant, while a duodenal adenoma with low-grade dysplasia was seen in two participants. 100 % and 89 % of study participants gave a blood or a stool sample, respectively. All participants answered the questionnaire on dietary and lifestyle habits.

CONCLUSION

 The Prä-GIT study was designed to generate a database for premalignant and early cancerous lesions of the uGIT in Germany in asymptomatic individuals presenting for a regular screening colonoscopy. The current pilot study has delivered important insights into the feasibility of the main study protocol. Additionally, the pilot study has shown a high rate of acceptance of an additional uGIT examination in this study population.

Methods that Assist Traction during Endoscopic Submucosal Dissection of Superficial Gastrointestinal Cancers: A Systematic Literature Review

Endoscopic submucosal dissection (ESD) is a well-established method for the treatment of early-stage gastrointestinal neoplasms. Adequate submucosal exposure is one of the most significant factors related to an effective and safe dissection. The aim of this systematic review was to evaluate the effcacy and safety of various methods that assist traction during ESD of precancerous and earlystage neoplastic lesions of the gastrointestinal tract. We performed an electronic search of the MEDLINE and the Cochrane Controlled Trials Register databases for relevant studies published up to May 2019. Trials exclusively recruiting patients undergoing ESD for superficial gastrointestinal cancer were considered eligible for inclusion. Thirty-three articles including 3,134 patients met the inclusion criteria. The studies evaluated different approaches for widening the endoscopic view, including magnetic anchor-guided ESD (3 studies), use of a second endoscope (5 studies), clip-involving technique (21 studies), and miscellaneous methods (4 studies). Among them, only 6 were randomized controlled trials evaluating different approaches. Overall, the implementation of methods that assist traction during ESD significantly improved the operating time and R0 resection rate and decreased the rate of complications (bleeding and perforation). Interventions that assist traction seem effcacious in improving tissue traction, thus facilitating ESD performance.

A technical review of artificial intelligence as applied to gastrointestinal endoscopy: clarifying the terminology

Background and aim  The growing number of publications on the application of artificial intelligence (AI) in medicine underlines the enormous importance and potential of this emerging field of research. In gastrointestinal endoscopy, AI has been applied to all segments of the gastrointestinal tract most importantly in the detection and characterization of colorectal polyps. However, AI research has been published also in the stomach and esophagus for both neoplastic and non-neoplastic disorders. The various technical as well as medical aspects of AI, however, remain confusing especially for non-expert physicians. This physician-engineer co-authored review explains the basic technical aspects of AI and provides a comprehensive overview of recent publications on AI in gastrointestinal endoscopy. Finally, a basic insight is offered into understanding publications on AI in gastrointestinal endoscopy.

Outcomes of endoscopic submucosal dissection (ESD) during live endoscopy events (LEE) - a 13-year follow-up

Background and study aims  There are no data showing the outcome of ESD during live endoscopy events (LEE). ESD performed during the Augsburg Endo-Update LEE were compared with matched routine procedures with the aim of demonstrating non-inferiority of LEE ESD. Patients and methods  ESD performed during the Endo-Update between 2006 and 2018 were reviewed. The controls were routine procedures matched according to age, location and lesion size. Resection, recurrence, survival and complication rates, procedure time and propofol sedation were assessed. Clinically relevant margins were assumed for resection and complication rates, procedure time and propofol sedation quantity. Results  Thirty-eight ESD were performed in the given time period, and were compared with 38 matched routine ESD. En bloc and curative resection rates in the LEE group and in the control group were 100 % and 87 % as well as 84 % and 71 % respectively, while procedure times were 135 and 125 minutes, respectively. Non-inferiority was demonstrated for resection rates and procedure time. The complication rate was lower in the LEE group as compared with the control group (5 % vs 13 %) while propofol sedation was similar in both groups (863 mg vs 872 mg). Recurrence and 5-year survival rates for both groups were 4 % vs 0 % and 70 % vs 65% respectively. Conclusions  The resection rate and procedure time of ESD during LEE was non-inferior to those of routine ESD procedures. Comparison of the complication rates, however, was inconclusive owing to the low patient number and complication risk in both groups.

Immunoglobulin G4 (IgG4)-related disease of the stomach - a challenging differential diagnosis in suspected gastric cancer

BACKGROUND

 Immunoglobulin G4-related disease (IgG4-RD) can involve different organs and is diagnosed by a combination of clinicopathological features, including storiform fibrosclerosis infiltrated by numerous IgG4-positive plasma cells that frequently forms tumor-like lesions with or without associated obliterative phlebitis. Involvement of the stomach is rare and can occur as part of a multiorgan involvement of IgG4-RD or as isolated gastric involvement.

CASE REPORT

 We report 2 female patients with therapy-refractory gastric ulcers associated with gastric wall thickening and lymphadenopathy that were highly suggestive of gastric cancer or lymphoma. Biopsies failed to confirm a diagnosis, and IgG4-RD was diagnosed only after surgical resection in both patients. The previous literature on gastric IgG4-RD is summarized and shows different characteristics in patients with multiorgan IgG4-RD and isolated gastric IgG4-RD. As reported for autoimmune pancreatitis type 1, patients with multiorgan IgG4-RD are mainly elderly men with frequently elevated serum IgG4 concentrations. In contrast, isolated gastric IgG4-RD predominantly affects female patients with normal serum IgG4 levels. Surgical resection is commonly performed due to the clinical suspicion of malignancy and the absence of findings indicative of IgG4-RD on biopsy. Today, diagnosis is confirmed histopathologically only after resection.

CONCLUSION

 IgG4-RD should be taken into account when gastric malignancy is suspected endoscopically or radiologically and biopsies fail to confirm the presence of a malignancy (especially subepithelial tumors or refractory gastric ulcers). Serum IgG4 concentrations are insufficient to confirm localized gastric IgG4-RD. Diagnostic workups need to be improved to avoid unnecessary surgical resections with the attendant potential morbidity and mortality.

Over-the-scope clip in peptic ulcer bleeding: clinical success in primary and secondary treatment and factors associated with treatment failure

Background and study aims  It is unclear if the clinical success rate of the over-the-scope-clip (OTSC) in peptic ulcer bleeding (PUB) is comparable when it is used in the first- or in the second-line of treatment. Patients and methods  Data on endoscopic treatment (first- vs. second-line) in PUB with OTSC and clinical data were analyzed. The primary outcome was the clinical success of hemostasis, defined as the absence of recurrent bleeding or further intervention. Secondary outcomes were factors associated with OTSC failure. Results  From April 2014 to March 2018, 100 patients (age 72 [20 - 98] y, female 36 %) with PUB in the stomach or the duodenum were treated endoscopically with the OTSC. The OTSC was used as a first-line procedure (primary-OTSC) in 66 pts. Successful hemostasis could be achieved in 90.9 %. After failure of an initial endoscopic treatment, 34 patients were treated with the OTSC (secondary-OTSC) and the treatment was successful in 94.1 %. Recurrent bleeding occurred in n = 10 for primary-OTSC (16.7 %) and in n = 7 pts in the secondary-OTSC (21.9 %) ( P  = 0.81). Clinical success in the primary-OTSC was 75.8 % and 73.5 % in the secondary-OTSC respectively. Conclusions  The OTSC has a high rate of initial bleeding control in first- and second line treatment of PUB. OTSC failure occurs more often in the duodenum than in the stomach and results in longer intensive care unit stay, higher amount of transfusions, and a higher reimbursement per case.

Topographic mapping of a specimen after endoscopic submucosal dissection

Background and study aims  Mapping of pathologic specimens after endoscopic submucosal dissection (ESD) is common practice in Asian countries, especially in Japan. However, there is a lack of awareness for this technique in Europe. In this report, we demonstrate the feasibility and benefits of topographic mapping in a Western setting.

Favorable radiation field decrease in gastric marginal zone lymphoma : Experience of the German Study Group on Gastrointestinal Lymphoma (DSGL)

PURPOSE

Long-term impact of stage-adapted field reduction in a large cohort of gastric marginal zone lymphoma (gMZL) patients treated conservatively with curative radiation therapy (RT).

PATIENTS AND METHODS

Prospective analysis of paper records of 290 patients with stage IE-IIE gMZL, treated in 78 radiotherapeutic institutions in Germany from 1992-2013. Stage-adapted radiation fields decreased from extended field (EF) to involved field (IF) over the course of three consecutive prospective trials of the German Study Group on Gastrointestinal Lymphoma (DSGL). Treatment results were compared between the three cohorts.

RESULTS

Overall collective with median age of 60 years, slight male predominance (m:f = 1.1:1) and ratio of disease stage I:stage II = 2.1:1. Median follow-up 6.4 years in total: 13.0 years in the first gastrointestinal study (GIT 1992), 8.2 years in the second (GIT 1996) and 4.7 years in the third study (DSGL 01/2003). Stage-adapted radiation field decrease together with further technological development led to reduced relative frequencies of acute/chronic adverse effects and until now was accompanied by lower disease recurrence. The third study design with smallest field size (IF in stage I, locoregional EF in stage II) achieved the best survival outcome at the 5‑year follow-up (overall survival 92.7%, event-free survival 89.5% and lymphoma-specific survival 100.0%). Disease relapse observed in 10 patients. Cumulative incidence of disease-specific death was 1.7% of the followed patients. Primary disease stage associated with lymphoma-specific survival.

CONCLUSION

Stage-adapted reduction towards IF in gMZL resulted in favorable adverse effects, local control and survival rates. These results support further decreases in modern RT of gMZL.

Endoscopic submucosal dissection for rectal neoplasia extending to the dentate line: European experience

Background and study aims  The ideal treatment strategy for rectal neoplasia extending to the dentate line (RNDL) is not well defined. Endoscopic mucosal resection (EMR) and submucosal dissection (ESD) compete with surgical techniques such as transanal endoscopic microsurgery (TEM). Non-Asian data and prospective data on ESD are lacking. The study aim was to evaluate the role of ESD in treatment of RNDL in a Western center. Patients and methods  Eighty-six patients with rectal adenomas were included. ESD was performed in 86 rectal adenomas including 24 RNDLs (27.9 %) and 62 lesions distant from the dentate line (72.1 %). Results  En bloc resection rate was comparable (91.7 % vs. 93.5 %, P  = 0.670) between ESD for RNDL and non-RNDL. R0 resection rate was significantly lower in ESD for RNDL compared to that for non-RNDL (70.8 % vs 88.7 %; P  = 0.039), but most non-R0 resection was unclear margin (Rx) and was not obvious positive margin (R1). Accordingly, the recurrence rate after ESD for RNDL (4.5 %) was not statistically different from that for non-RNDL (0 %, P  = 0.275) and was lower than that previously reported for EMR. Median procedure time was 127 vs. 110 minutes ( P  = 0.182). Risk of delayed bleeding (20.8 % vs. 0 %, P  = 0.001) and postinterventional pain (33.3 % vs. 14.5 %, P  = 0.07) increased in RNDL cases, but they were managed conservatively. Incidence of stricture (4.2 % vs. 1.6 %, P  = 0.483) and perforation (0 % vs. 1.6 %, P  = 1.000) were similar. Conclusions  ESD is a feasible and safe resection technique for RNDLs. A randomized controlled trial comparing ESD to other methods (EMR or transanal surgery) is warranted.

Colonoscopic full-thickness resection using an over-the-scope device: a prospective multicentre study in various indications

OBJECTIVE

Endoscopic full-thickness resection (EFTR) is a novel treatment of colorectal lesions not amenable to conventional endoscopic resection. The aim of this prospective multicentre study was to assess the efficacy and safety of the full-thickness resection device.

DESIGN

181 patients were recruited in 9 centres with the indication of difficult adenomas (non-lifting and/or at difficult locations), early cancers and subepithelial tumours (SET). Primary endpoint was complete en bloc and R0 resection.

RESULTS

EFTR was technically successful in 89.5%, R0 resection rate was 76.9%. In 127 patients with difficult adenomas and benign histology, R0 resection rate was 77.7%. In 14 cases, lesions harboured unsuspected cancer, another 15 lesions were primarily known as cancers. Of these 29 cases, R0 resection was achieved in 72.4%; 8 further cases had deep submucosal infiltration >1000 µm. Therefore, curative resection could only be achieved in 13/29 (44.8%). In the subgroup with SET (n=23), R0 resection rate was 87.0%. In general, R0 resection rate was higher with lesions ≤2 cm vs >2 cm (81.2% vs 58.1%, p=0.0038). Adverse event rate was 9.9% with a 2.2% rate of emergency surgery. Three-month follow-up was available from 154 cases and recurrent/residual tumour was evident in 15.3%.

CONCLUSION

EFTR has a reasonable technical efficacy especially in lesions ≤2 cm with acceptable complication rates. Curative resection rate for early cancers was too low to recommend its primary use in this indication. Further comparative studies have to show the clinical value and long-term outcome of EFTR in benign colorectal lesions.

TRIAL REGISTRATION NUMBER

NCT02362126; Results.

Anthropogenic contribution and influencing factors on metal features in fluvial sediments from a semi-arid Mediterranean river basin (Tafna River, Algeria): A multi-indices approach

Metals in river sediments from a semi-arid Mediterranean basin were investigated from upstream to downstream during contrasting hydrological conditions in 2014 and 2015. The level and origin of the contamination were evaluated using several geochemical and isotopic indicators. Elements were grouped by their level of contamination: high (Pb > Cd > Zn > Cu) and low (Al, Fe, Cr, Co, Ni). Multiple local sources of contamination were identified (industrial, agricultural and domestic waste), as well as very specific ones (gasoline station) and diffuse pollution from atmospheric deposition (gasoline, ores, aerosols). During storm events, the upstream dams can either be secondary sources of contamination or dilutors through particles derived from natural erosion. The contamination was slowed downstream due to the river geomorphology, but eventually washed into the Mediterranean Sea by intense storm events. Naturally derived elements (Co, Ni, Cr, As) were associated with Al, Fe and Mn oxides or clays, and anthropogenic originated metals with phosphorus (Cd and Zn), sulphur (Cu) and POC (Pb enrichment). Cadmium and Pb were the most available metals upstream and at the outlet, but their availability was not strictly related to their degree of contamination. These conclusions could be drawn thanks to an approach by multiple indicators.