Resectability of Small Duodenal Tumors: A Randomized Controlled Trial Comparing Underwater Endoscopic Mucosal Resection and Cold Snare Polypectomy

INTRODUCTION

Underwater endoscopic mucosal resection (UEMR) and cold snare polypectomy (CSP) are novel endoscopic procedures for superficial nonampullary duodenal epithelial tumors (SNADET). However, consensus on how to use both procedures appropriately has not been established. In this study, we evaluated treatment outcomes of both procedures, including resectability.

METHODS

In this single-center randomized controlled study conducted between January 2020 and June 2022, patients with SNADET ≤12 mm were randomly allocated to UEMR and CSP groups. The primary end point was sufficient vertical R0 resection (SVR0), which was defined as R0 resection including a sufficient submucosal layer. We compared treatment outcomes including SVR0 rate between groups.

RESULTS

The SVR0 rate was significantly higher in the UEMR group than in the CSP group (65.6% vs 41.5%, P = 0.01). By contrast, the R0 resection rate was not significantly different between study groups (70.3% vs 61.5%, P = 0.29). The submucosal layer thickness was significantly greater in the UEMR group than in the CSP group (median 546 [range, 309-833] μm vs 69 [0-295] μm, P < 0.01). CSP had a shorter total procedure time (median 12 [range, 8-16] min vs 1 [1-3] min, P < 0.01) and fewer total bleeding events (9.4% vs 1.5%, P = 0.06).

DISCUSSION

UEMR has superior vertical resectability compared with CSP, but CSP has a shorter procedure time and fewer bleeding events. Although CSP is preferable for most small SNADET, UEMR should be selected for lesions that cannot be definitively diagnosed as mucosal low-grade neoplasias.

Closure of large mucosal defects for prevention of strictures after duodenal endoscopic submucosal dissection (with video)

BACKGROUND AND AIMS

Although lesions occupying a large circumference are associated with the risk of post-endoscopic submucosal dissection (ESD) strictures, the corresponding data for duodenal lesions are unknown. We aimed to analyze the incidence of post-ESD strictures after wide-field duodenal ESD.

METHODS

In this retrospective study of duodenal lesions treated with ESD between July 2010 and August 2021, we included lesions that resulted in mucosal defects occupying more than half of the circumference and excluded lesions located in bulbs and involving Vater's papilla. We analyzed the incidence rates of stricture and luminal narrowing, in addition to bleeding and perforation as the outcomes in this study. Stricture was defined as the inability of the endoscope to pass through the lumen. A single endoscopist reviewed all endoscopic images and judged the degree of luminal narrowing.

RESULTS

Eighty lesions were included, of which 2 involved mucosal defects occupying more than 90% of the circumference. The wound was closed, at least partially, in 90% in all lesions and in 86% of lesions with a mucosal defect occupying more than 75% of the circumference. None of the lesions caused delayed perforation and stricture, whereas 2 lesions caused delayed bleeding. Only 6 lesions caused luminal narrowing. When examined by the degree of closure, the rate of luminal narrowing increased with complete closure, incomplete closure, and nonclosure (4.9%, 9.1%, and 25.0%, respectively).

CONCLUSIONS

Suturing may prevent post-ESD bleeding and perforation as well as stricture formation in cases of duodenal tumors, with mucosal defects occupying a large circumference.

Red dichromatic imaging reduces bleeding and hematoma during submucosal injection in esophageal endoscopic submucosal dissection

BACKGROUND

Bleeding and hematoma formation during submucosal injection in esophageal endoscopic submucosal dissection (ESD) reduce the visibility of the submucosa. Red dichromatic imaging (RDI) is an endoscopic technique that provides better visualization of the deep submucosal blood vessels. We speculated that blood vessel injury could be avoided with RDI. This pilot study evaluated the role of RDI in preventing bleeding and hematoma formation during esophageal ESD.

METHODS

This was a single-center retrospective observational study. We examined 60 patients who underwent ESD with white light imaging (WLI) and RDI. A single endoscopist reviewed all of the surgical videos to document the incidence and severity of bleeding episodes. Eighteen videos provided adequate quality and detail, and the number of blood vessels traversing the mucosal incision lines of the lesions in these videos was evaluated under WLI and RDI.

RESULTS

The WLI group had a significantly higher incidence of hematomas per unit area compared to the RDI group (0.18/cm² [range 0-0.38] vs. 0 [0-0.18]/cm², p = 0.024). The WLI group also had a significantly higher incidence of total bleeding episodes compared to the RDI group (42.9% [range 21.7-60.4] vs 16.7% [range 13.8-22.9], p < 0.001). Significantly more blood vessels were visible under RDI compared to WLI (5 [range 4-8] vs. 2 [range 1-5], p = 0.0020).

CONCLUSION

RDI reduced the incidence of bleeding and hematoma formation during submucosal injection in esophageal ESD. It was assumed that the improvement of blood vessel visibility by RDI might have contributed to the result.

Differential diagnosis of superficial duodenal epithelial tumor and non-neoplastic lesion in duodenum by magnified endoscopic examination with image-enhanced endoscopy

BACKGROUND

Differential diagnosis of superficial duodenal epithelial tumors (SDETs) and non-neoplastic lesions (NNLs) in duodenum by endoscopy is difficult. Here, we attempted to distinguish them by magnified endoscopic examination with image-enhanced endoscopy (IEE-ME).

METHODS

Various IEE-ME findings of 95 SDETs who underwent endoscopic resection and 58 NNLs who underwent biopsy were retrospectively reviewed.

RESULTS

When we compared the IEE-ME findings of SDETs and NNLs, the presence of demarcation line (DL) (97.9% vs. 79.3%, P = 0.0002), white opaque substance (WOS) (84.2% vs. 1.7%, P < 0.0001) and light blue crest (LBC) (93.7% vs. 32.8%, P < 0.0001) and the absence of enlarged marginal epithelium (EME) (98.9% vs. 62.1%, P < 0.0001) were significantly more frequent in SDETs than NNLs. When divided into each superficial structure, it was the most effective to evaluate the combination of WOS and LBC as SDET with open-loop structure (OLS), and the combination of DL and EME as SDET with closed-loop structure (CLS). However, LBC was excluded because of low inter- and intra-observer agreements. Finally, the sensitivity, specificity and accuracy for the diagnosis of SDETs were 88.4%, 98.3% and 92.2%, respectively, and we developed an algorithm for the differential diagnosis of duodenal lesions.

CONCLUSION

We could distinguish SDET from NNL, diagnosed SDET as presence of WOS indicated OLS of superficial structure, and presence of DL and absence of EME indicated CLS of superficial structure.

Efficacy of partial injection underwater endoscopic mucosal resection for superficial duodenal epithelial tumor: Propensity score-matched study (with video)

BACKGROUND AND AIM

Underwater endoscopic mucosal resection (UEMR) has been reported as effective endoscopic treatment for superficial duodenal epithelial tumors (SDETs). However, it has been reported that a notable problem of UEMR for SDETs is that en bloc resection rate is relatively low. Therefore, we proposed a novel technique to improve en bloc resection rate: UEMR combining partial submucosal injection (PI-UEMR). The aim of this study is to evaluate efficacy and safety of PI-UEMR for SDETs by comparing to UEMR.

METHODS

This is a retrospective observational study in a single center. The patients who underwent UEMR or PI-UEMR from June 2010 to August 2020 were included in this study. Eligible patients were selected from included patients in a 1:1 ratio using propensity score matching. The clinical outcomes of endoscopic resection (procedure time, en bloc resection rate, complication rate [immediate perforation, delayed bleeding, delayed perforation]), and histopathological diagnosis (adenoma/cancer) were compared between each group.

RESULTS

Two hundred and twenty-eight patients were included in this study. Of included patients, 47 patients were selected in each group by propensity score matching. There were no statistical differences in procedure time (11 ± 1.2 min vs. 9 ± 1.2 min, P = 0.30), complication rate (immediate perforation [0% vs. 2%, P = 0.12], delayed bleeding [0% vs. 2%, P = 0.12], and no delayed perforation) and histopathological diagnosis (adenoma; 100% vs. 96%, P = 0.14) in each group. However, en bloc resection rate of PI-UEMR was significantly higher than UEMR (96% vs. 83%, P < 0.05).

CONCLUSION

Partial submucosal injection UEMR might be superior procedure for en bloc resection in SDETs compare to UEMR.

Feasibility Study of Partial Submucosal Injection Technique Combining Underwater EMR for Superficial Duodenal Epithelial Tumors

BACKGROUND AND AIMS

Endoscopic mucosal resection (EMR) and Underwater EMR have been reported as effective endoscopic treatment for superficial duodenal tumor (SDET). However, a notable problem of EMR for SDET is technical difficulty for the lesion with non-lifting sign, and it of UEMR is that en bloc resection rate is relatively low. Therefore, we performed partial submucosal injection combining UEMR (PI-UEMR). The aim of this study is to evaluate feasibility and safety of this technique for duodenal tumor.

METHODS

This is a prospective observational study from tertiary care hospital. We performed PI-UEMR in patients with SDET that is 13-20 mm in diameter, or less than 13 mm with technical difficulty for EMR and UEMR from January 2019 to March 2020. Primary outcome was en bloc resection rate. Secondary outcomes were R0 resection rate, mean total procedure time, intra- and post-procedure complication.

RESULTS

Thirty patients were included in this study. Mean age was 62 ± 12 years old. Three fourths lesions were located at anal side from major papilla. Median lesion size was 12 mm [IQR 10-16 mm]. Twenty-four cases were taken endoscopic biopsy in prior hospital and observed biopsy scar. En bloc resection rate was 97%. Ro resection rate was 83%. Mean total procedure time was 17 ± 12 min. And there was an only one case of complication, intra-procedure bleeding that was controllable endoscopically.

CONCLUSIONS

PI-UEMR might be very useful and safe technique of endoscopic resection for SDET including relatively large lesions.

Feasibility of endoscopic resection for large pedunculated duodenal lesions (with video)

BACKGROUND

A standard treatment method for pedunculated duodenal lesions has not yet been established. This study aimed to evaluate the feasibility of endoscopic resection (ER) for pedunculated duodenal lesions, especially for large lesions.

METHODS

This study retrospectively reviewed cases of pedunculated duodenal lesions treated with ER at our institute between July 2010 and January 2021. We collected data on the clinical characteristics and treatment outcomes. In addition, the cases were divided based on the treatment provided for the lesion, i.e., the ESD and snare resection groups, and we compared the data between the two groups.

RESULTS

Thirty-eight cases were included in this study. The overall en bloc resection rate was 95%. No perforation occurred in any of the cases. There were 10 cases treated with ESD, which were considered difficult to achieve en bloc resection using snare forceps, and 28 cases treated with snare resection. Although the median lesion size was significantly larger in the ESD group than in the snare resection group (27 [range 23-66] vs. 19 [range 6-55] mm, P = 0.0052), treatment outcomes were not significantly different between the two groups. Among the 10 cases treated using ESD, en bloc resection was achieved in all cases, along with specimen retrieval without any perforations, despite the large size of the lesions.

CONCLUSION

ER could be performed to achieve a high en bloc resection rate without any perforations in pedunculated duodenal lesions, even in extremely large (e.g., ≧ 60 mm) lesions, suggesting that ER is feasible and may be an alternative to surgical resection for large pedunculated duodenal lesions.

Endoscopic hand suturing for mucosal defect closure after gastric endoscopic submucosal dissection may reduce the risk of postoperative bleeding in patients receiving antithrombotic therapy

OBJECTIVES

Endoscopic hand suturing (EHS) is expected to decrease the risk of post-endoscopic submucosal dissection (ESD) bleeding by closing mucosal defects. We investigated the efficacy of EHS after gastric ESD in patients with antithrombotic agents.

METHODS

In this prospective single-arm trial, patients taking antithrombotic agents for cardiovascular disease, arrhythmia, cerebrovascular disease and/or peripheral arterial disease and having <3-cm gastric neoplasms were recruited. The mucosal defects after ESD were closed by EHS in which the needle was delivered through an overtube, and the mucosal rim of the defect was continuously sutured in a linear fashion by manipulating the needle grasped with the needle holder, followed by cutting the remnant suture and retrieval of the needle. The primary endpoint was the incidence of postoperative bleeding within 4 weeks after ESD.

RESULTS

Twenty-two lesions in 20 patients (continuing antiplatelet agents in 11, anticoagulant agents in eight, both in one) underwent ESD followed by EHS. All defects (median size, 30 mm; range, 12-51 mm) were completely closed by EHS and remained closed on postoperative day 3. The median number of stitches was six (range, 4-8) and median suturing time was 36 (range, 24-60) min. There were no adverse events during/after EHS or postoperative bleeding.

CONCLUSIONS

Postoperative bleeding was not observed in patients taking antithrombotic agents without perioperative cessation. EHS appears to be useful for prevention of post-gastric ESD bleeding in high-risk patients. (Clinical registration number: UMIN000024184).

Predictors of technical difficulty for complete closure of mucosal defects after duodenal endoscopic resection

BACKGROUND AND AIMS

It has been reported that the prophylactic closure of mucosal defects after duodenal endoscopic resection (ER) can reduce delayed adverse events; however, under certain circumstances, this can be technically challenging. Therefore, the aim of this study was to determine the predictors of difficulty during the complete closure of mucosal defects after duodenal ER.

METHODS

This was a retrospective study of duodenal lesions that underwent ER between July 2010 and May 2020. We reviewed the endoscopic images and analyzed the relationships between the degree of closure or closure time and clinical features of the lesions using univariate and multivariate analyses.

RESULTS

We analyzed 698 lesions. The multivariate analysis revealed that lesion location in the medial or anterior wall (odds ratio, 2.8; 95% confidence interval, 1.36-5.85; P < .01) and a large lesion size (odds ratio, 1.4; 95% confidence interval, 1.07-1.89; P = .03) were independent predictors of an increased risk of incomplete closure. Moreover, a large lesion size (β coefficient, .304; P < .01), an occupied circumference over 50% (β coefficient, .178; P < .01), intraoperative perforation (β coefficient, .175; P < .01), treatment period (β coefficient, .143; P < .01), and treatment with endoscopic submucosal dissection (β coefficient, .125; P < .01) were independently and positively correlated with a prolonged closure time in the multiple regression analysis.

CONCLUSIONS

This study revealed that lesion location in the medial or anterior wall and lesion size affected the incomplete closure of mucosal defects after duodenal ER, and lesion size, occupied circumference, intraoperative perforation, treatment period, and treatment method affected closure time.

External drainage of bile and pancreatic juice after endoscopic submucosal dissection for duodenal neoplasm: Feasibility study (with video)

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) for superficial duodenal epithelial tumors (SDETs) is technically difficult and has a high risk of adverse events. Endoscopic nasobiliary and nasopancreatic duct drainage (ENBPD) may reduce the risk of delayed adverse events by preventing exposure of the post-ESD mucosal defect to bile and pancreatic juice. This study was performed to evaluate the safety and feasibility of ENBPD after duodenal ESD.

METHODS

Patients who underwent ESD for SDETs from July 2010 to March 2020 were included. We collected data on the success rate of ENBPD, adverse events due to insertion of a side-viewing endoscope, and pancreatitis after ENBPD. We also collected the clinical outcomes of duodenal ESD, including the incidence rate of delayed adverse events (defined as bleeding or perforation found after the endoscopic procedure).

RESULTS

Among 70 patients without complete closure of the post-ESD mucosal defect, ENBPD was successfully performed in all 25 patients including 21 cases inserted immediately after ESD and four cases inserted later. There were no adverse events associated with ENBPD procedure intraoperatively, while pancreatitis after ENBPD occurred in four patients (16.0%). No patients who underwent immediate ENBPD required intervention for an intra-abdominal abscess or delayed perforation, whereas 3 of 49 patients (6.1%) who did not undergo immediate ENBPD required surgery or drainage of an abscess.

CONCLUSIONS

Endoscopic nasobiliary and nasopancreatic duct drainage is technically feasible and might provide effective prophylaxis for delayed adverse events, even if a large mucosal defect is present after ESD.

Water pressure method for duodenal endoscopic submucosal dissection (with video)

BACKGROUND AND AIMS

Duodenal endoscopic submucosal dissection (ESD) is considered technically challenging and has a high risk of adverse events. However, we recently made some progress with the ESD technique and device by introducing 2 features: a water pressure (WP) method and a second-generation ESD knife (DualKnife) with a water jet function (DualKnife J). The present study aimed to assess whether these changes improved the clinical outcomes of duodenal ESD.

METHODS

This was a retrospective observational study. Among all patients who underwent ESD for superficial duodenal epithelial tumors from June 2010 to December 2018, patients in whom a single expert performed the procedure were included in this study. Various factors, including the use of the WP method and ESD devices (DualKnife or DualKnife J) and the treatment phase (early, mid, and late), were analyzed to determine whether they were associated with intraprocedural perforation and procedure time. Treatment phase was assigned by dividing the study population equally into 3 subgroups according to the treatment phase.

RESULTS

The procedure time was significantly shorter, and the proportion of patients with intraprocedural perforations was the lowest in the late phase. Multivariate analysis of the use of the WP method revealed that it significantly decreased the intraprocedural perforation rate (odds ratio, 0.39; 95% confidence interval, 0.16-0.96), and analysis of the use of both the WP method (β coefficient, -0.40; P < .01) and the DualKnife J (β coefficient, -0.10; P = .032) revealed they were independently and negatively correlated with procedure time.

CONCLUSION

The present study reveals that the WP method significantly reduced the intraprocedural perforation rate and that both the WP method and the DualKnife J significantly shortened procedure times for duodenal ESD.

Feasibility study comparing underwater endoscopic mucosal resection and conventional endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumor < 20 mm

BACKGROUND AND AIM

Underwater endoscopic mucosal resection (UEMR) has been reported as an alternative to conventional EMR for superficial non-ampullary duodenal epithelial tumors (SNADET). However, the detailed outcomes are unclear. This study aimed to compare the clinical outcomes between UEMR and EMR for SNADET <20 mm.

PATIENTS AND METHODS

This is a retrospective observational study using a prospective maintained database. From November 2017 to December 2018, 104 consecutive cases of attempted UEMR for SNADET <20 mm were prospectively allocated. A total of 240 cases of attempted EMR were chosen as historical controls. We compared technical success rate, defined as the resection rate without conversion to ESD; en bloc resection rate; R0 resection rate; and adverse event rate. Next, multivariate analyses were constructed to identify predictors of conversion to ESD, piecemeal resection, and RX or R1 (RX/R1) resection.

RESULTS

Technical success rate of UEMR was significantly higher than that of EMR (87% and 70%, P < 0.01). En bloc resection and R0 resection rates of UEMR were significantly lower than those of EMR (en bloc resection: 87% vs 96%, P < 0.01; R0 resection: 67% vs 80%, P = 0.05). Concerning adverse events, there were no significant differences. In multivariate analyses, attempted EMR, lesion size and depressed type were independent predictors of conversion to ESD. Attempted UEMR was an independent predictor of piecemeal resection and RX/R1 resection.

CONCLUSION

The present study indicated that UEMR could be a feasible endoscopic resection method for SNADET (UMIN000025442).

Endoscopic suturing promotes healing of mucosal defects after gastric endoscopic submucosal dissection: endoscopic and histologic analyses in in vivo porcine models (with video)

BACKGROUND AND AIMS

Endoscopic suturing of mucosal defects after endoscopic submucosal dissection (ESD) is expected to prevent postoperative adverse events. We aimed to endoscopically and histologically evaluate the healing process of post-ESD mucosal defects closed with endoscopic hand suturing (EHS) in in vivo porcine models.

METHODS

Twelve mucosal defects (2 cm in size) were created in 2 pigs (6 defects per pig). Initially, 2 defects were created: one was closed with EHS (sutured group) and the other was kept open (control group). On postoperative days (PODs) 7 and 14, 2 additional defects were created in each session, and they were treated in the same manner as in the initial procedure. On POD 21, the entire stomach, with the 6 lesion sites, was extracted for histologic evaluation after endoscopic observation.

RESULTS

Endoscopically, all sutured sites remained closed in all sessions (PODs 7, 14, and 21). Histologically, on POD 14, the epithelium and muscularis mucosae were appropriately connected. The mucosae were covered with the epithelium without inversion of the mucosal edge in the sutured group, whereas the ulcer bed was exposed in the control group. Furthermore, the degree of neovascularity and fibroblasts in the submucosa was smaller in the sutured group than that in the control group.

CONCLUSIONS

Our findings suggest that endoscopic suturing promotes healing of post-ESD mucosal defects histologically in in vivo porcine models. Thus, endoscopic mucosal closure after ESD might be clinically useful for the prevention of delayed perforation/bleeding if secure suturing is performed endoscopically.

Management of perforation related to endoscopic submucosal dissection for superficial duodenal epithelial tumors

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is being performed more frequently as a local treatment for superficial duodenal epithelial tumors (SDETs). However, ESD for SDETs is technically difficult because of specific anatomic features that increase the risk of perforation and often require surgery. This study was performed to evaluate the management of ESD-related perforation in patients with SDETs.

METHODS

Patients who underwent ESD for SDETs from July 2010 to December 2018 were studied. We collected data on complete closure, insertion of endoscopic nasobiliary and pancreatic duct drainage (ENBPD) tubes, and additional interventions. We also evaluated clinical outcomes, including the fasting period, hospital stay, and maximum serum C-reactive protein level.

RESULTS

ESD was completed in 264 patients with SDETs. Perforation was observed in 36 patients, including 4 patients with delayed perforation. Among 32 patients with intraoperative perforation, complete closure was achieved in 13 patients. Compared with patients without complete closure, the fasting period and hospital stay were significantly shorter and the maximum serum C-reactive protein level was significantly lower in patients with complete closure, which were equivalent to those in patients without perforation. In patients without complete closure for mucosal defect, no additional interventions were required when an ENBPD tube was inserted, whereas 2 patients without ENBPD tube insertion underwent additional interventions such as percutaneous drainage and a surgical operation.

CONCLUSIONS

Perforation associated with ESD for SDETs required complex conservative management with complete closure or insertion of an ENBPD tube.

How I do it: Endoscopic diagnosis for superficial non-ampullary duodenal epithelial tumors

There are no reports on detailed endoscopic diagnosis of superficial non-ampullary duodenal epithelial tumors (SNADET) except for relatively small case series. Herein, we conducted a prospective observational study to investigate the relationship between endoscopic findings and histopathological diagnosis of SNADET. A total of 163 SNADET diagnosed using magnified endoscopic examination with image-enhanced endoscopy (IEE-ME) were prospectively registered in this study. We investigated location, size, macroscopic type, color, and IEE-ME findings including surface structure (closed- or open-loop) and presence of white opaque substance (WOS) in SNADET. We analyzed association between these findings and histopathological diagnosis of SNADET based on the Vienna classification (VCL) using logistic regression analysis. In univariate analysis, lesion size, superficial structure, and WOS deposition showed statistical significance, and the oral side of the lesion location showed statistical tendency for association with VCL C4/5. In multivariate analysis, lesion size (odds ratio [OR], 2.92; 95% CI, 1.94-4.39; P < 0.05) and negative WOS (OR, 5.59; 95% CI, 1.72-18.1; P < 0.05) were significantly associated with VCL C4/5 lesions. Superficial structures with a closed-loop pattern on the surface showed statistical tendency for predicting VCL C4/5 lesions (OR, 2.15; 95% CI, 0.86-5.37; P = 0.10). Based on these findings, we concluded that negative WOS by IEE-ME and lesion size were independent predictors of VCL C4/5 SNADET. These factors may help us to understand of pathophysiology of SNADET and to select appropriate therapeutic strategies.

Feasibility of endoscopic submucosal dissection for colorectal neoplasia at anastomotic sites: a retrospective study

BACKGROUND

Metachronous colorectal lesions sometimes occur at anastomotic sites following colorectal surgery, which increases the risk of developing colorectal cancer. However, these lesions are difficult to treat even with minimally invasive methods such as endoscopic submucosal dissection (ESD). Thus, we aimed to evaluate the outcomes of ESD for colorectal lesions at anastomotic sites following colorectal surgery.

METHODS

We retrospectively investigated 11 patients with post-surgical colorectal lesions at anastomotic sites who later underwent ESD from May 2010 to April 2019 at Keio University Hospital, Tokyo, Japan. We examined the patients' background (tumor location, macroscopic type, tumor size, histological type, and depth of invasion) and treatment outcomes (procedure duration, en bloc resection rate, R0 resection rate, and adverse events).

RESULTS

The patients' mean age was 66 years. There were two lesions in the transverse colon, six in the rectum, one in the anal canal, and two in the ileal pouch. The median tumor size was 25 mm. The macroscopic types were the protruded type (1 lesion) and the flat or depressed type (10 lesions). The pathological diagnoses were adenoma (4 lesions), intramucosal cancer (corresponding to high-grade dysplasia) (6 lesions), and muscularis propria cancer (1 lesion). The median procedure duration was 50 min; en bloc resection rate was 88.9% and R0 resection rate was 66.7%. The only adverse event was delayed post-ESD bleeding.

CONCLUSIONS

A high en bloc resection rate without perforation was achieved with ESD for lesions at anastomotic sites. Although ESD for lesions at anastomotic sites is a technically challenging procedure because of severe submucosal fibrosis, this approach could prevent the need for repeated surgical resection.

Predictors of technical difficulty with duodenal ESD

Background and study aims  Duodenal endoscopic submucosal dissection (ESD) is still considered technically challenging; however, few studies have objectively analyzed predictors of the technical difficulty. Therefore, the aim of the current study was to elucidate predictors of the technical difficulty of duodenal ESD. Patients and methods  This was a retrospective observational study. From June 2010 to June 2017, a total of 174 consecutive patients with superficial duodenal epithelial neoplasia who underwent ESD were included in this study. We tried to identify predictors for technical difficulty of ESD by defining technical difficulty as either procedure time > 100 minutes or intraprocedural perforation. Moreover, we constructed a scoring system consisting of factors that were significant in the multivariate analysis. Results  The proportion of patients with technical difficulty was 34.5 %. In the multivariate analysis, lesion location in flexural part [odds ratio (OR), 2.61; 95 % confidence interval (CI), 1.02 - 6.68], larger lesion size (> 40 mm) (OR, 5.26; 95% CI, 2.15 - 12.9), and occupied circumference > 50 % of the duodenum (OR, 5.80; 95 % CI, 1.83 - 18.4) were associated with technical difficulty. Conclusion  A lesion location in flexural part, lesion size >40 mm and occupied circumference > 50 % were risk factors for technical difficulty of duodenal ESD.

Current Status and Challenges of Endoscopic Treatments for Duodenal Tumors

BACKGROUND

Superficial tumors of the duodenum, other than ampullary tumors, have been traditionally considered rare. However, reports of this kind of tumor have increased in recent times, and the demand for minimally invasive treatments have also increasing.

SUMMARY

Adenomas and intramucosal carcinomas are target lesions for treatment. A preoperative diagnosis has not been established, but unnecessary biopsies increase the difficulty of treatment and should be avoided. Cold snare polypectomy, endoscopic mucosal resection (EMR), and underwater EMR are treatment options for small lesions. Endoscopic submucosal dissection enables secure resection even for large lesions, but it is technically demanding and associated with a higher complication rate. After endoscopic resections, exposure of digestive juices is believed to cause delayed complications. To prevent these complications, several closing and covering methods are proposed, with favorable clinical results. Key message: A treatment method should be chosen based on each patient's situation. With any of the treatment methods, post-resection measures are required to prevent delayed complications. Secure closure of resection wounds seems promising.

Clinical impact of closure of the mucosal defect after duodenal endoscopic submucosal dissection

BACKGROUND AND AIMS

Delayed adverse events (bleeding or perforation) are major concerns associated with duodenal endoscopic submucosal dissection (ESD). The aim of this study was to assess the efficacy of prophylactic closure of the mucosal defect after duodenal ESD.

METHODS

This is a retrospective study from a university hospital. One hundred sixty-eight patients (173 lesions) who underwent duodenal ESD between July 2010 and June 2017 were included in this study. The study participants were divided into 3 subgroups according to the degree of closure: complete group, incomplete group, and unclosed group. The proportion of delayed adverse events, maximum serum level of C-reactive protein (CRP), and total length of hospital stay were compared among these subgroups. Moreover, a multivariate logistic regression model was constructed to identify the risk factors for delayed adverse events.

RESULTS

The proportion of delayed adverse events in the complete group, incomplete group, and unclosed group were 1.7%, 25%, and 15.6%, respectively. The difference between the complete group and the other groups was significant (P < .01). The maximum serum CRP level was much lower (1.51 ± 2.18 mg/dL vs 6.28 ± 10.0 mg/dL, P < .01), and the length of hospital stay was significantly shorter in the complete group than in the incomplete/unclosed group (median [range] 5 [5-14] days vs 8 [4-59] days, P < .01). Multivariate analysis revealed that complete closure had a significant decrease in delayed adverse events (odds ratio [OR], 0.055; 95% confidence interval [CI], 0.01-0.29; P < .01), and a lesion located distal from the descending part showed a statistical tendency to an increase in delayed adverse events (OR, 4.48; 95% CI, 0.85-23.6; P = .08).

CONCLUSION

The present study revealed that complete closure of the mucosal defect after duodenal ESD significantly decreased the number of delayed adverse events and improved other outcomes.

Outcomes of endoscopic resection for superficial duodenal epithelial neoplasia

BACKGROUND AND AIMS

Pancreaticoduodenectomy is an invasive procedure, and endoscopic resection (ER) is an alternative therapy. However, details regarding the outcomes of ER are unknown, especially for superficial duodenal epithelial neoplasia (SDET). The aim of this study was to elucidate the outcomes of ER for SDET and to compare EMR with endoscopic submucosal dissection (ESD).

METHODS

This was a retrospective observational study. From June 2010 to June 2017, 320 cases of endoscopically resected SDET (146 EMR-treated cases and 174 ESD-treated cases) were included in this study. We analyzed the proportions of en bloc resection, R0 resection, perforation, and bleeding as outcomes of ER and compared outcomes between the EMR and ESD groups. Next, we collected data on the features and clinical course of cases with adverse events.

RESULTS

The proportions of en bloc resection and R0 resection among all cases were 96.6% and 83.4%, respectively. In over 95% of cases, ESD achieved en bloc resection, regardless of lesion size. The incidences of perforation and bleeding were 8.8% and 3.4%, respectively, and the former was largely successfully managed by conservative treatment. The mortality rate was 0%, and all patients were discharged with a median hospital stay of 8.5 days (range, 4-52 days). Evaluation of the hospital stay duration according to lesion circumference revealed a significantly longer duration for lesions present on the medial wall than for other lesions (median 41 vs 7 days, P = .0331).

CONCLUSION

The present study revealed that ER achieved secure en bloc resection, with the treatment type (ESD or EMR) selected according to the lesion size. A lesion located on the medial wall was associated with worse outcomes, such as prolonged hospital stay after perforation.

Potential for peritoneal cancer cell seeding in endoscopic full-thickness resection for early gastric cancer

BACKGROUND AND AIMS

During endoscopic full-thickness resection (EFTR) for cancers, whether exposure of the lumen to the abdominal cavity during the procedure is acceptable is controversial because of the potential risk of tumor cell seeding. To assess the possibility of transplantation as a result of contact with tumor cells during the procedure, we prospectively investigated the ability of cancer cells to be detached by touching the tumor surface.

METHODS

In 48 patients with a single early gastric cancer resected by endoscopic submucosal dissection, stamp cytology was performed by touching the surface of the specimens to glass slides. Samples were obtained from cancerous and noncancerous areas, constituting the study and control groups, respectively. The detection rate of malignant class IV or V (C-IV/C-V) samples was investigated with Papanicolaou staining. The rate of CD44v9-positive cases, a cancer stem cell marker, was assessed in C-IV/C-V samples with immunohistochemical staining.

RESULTS

Detection rates of C-IV/C-V samples in the cancerous group (53/192 slides, 27.6%) differed significantly from those of the C-IV/C-V samples in the noncancerous group (0/96 slides, 0%). Among the 53 slides of C-IV/C-V samples in the cancerous group, CD44v9 cells were expressed in 18 slides (34.0%).

CONCLUSIONS

These data suggest that cancer cells, including cancer stem cells, in early gastric cancers are easily detached via contact with the tumor surface. In EFTR, a nonexposure approach is recommended to avoid the risk of iatrogenic cancer cell seeding via contact with and transplantation of cancer cells.

Endoscopic hand-suturing for defect closure after gastric endoscopic submucosal dissection: a pilot study in animals and in humans

Background and study aims Mucosal suturing enables reliable and optimal defect closure after endoscopic treatments. We developed and investigated the feasibility of endoscopic hand-suturing (EHS) after gastric endoscopic submucosal dissection (ESD) in porcine in vivo models and in human clinical cases. Patients and methods EHS involving continuous suturing of the mucosal layers using a through-the-scope needle-holder and absorbable barbed suture, was performed after gastric ESD in six live pigs and in eight consecutive patients. Success rates, adverse events, and suture maintenance were subsequently investigated. Results EHS was successfully completed in all six pigs and eight patients (100 %) without severe adverse events. However, at 1 week postoperatively the suture closures had not been maintained in all six porcine cases and in the first four clinical cases. In the later four clinical cases, wider and tight suturing of the mucosal edges ensured that the defects remained closed until postoperative week 4. Conclusion EHS is a feasible procedure that may facilitate secure and refined endoscopic surgeries. Mucosal closure in such cases can be maintained using firm suturing.Clinical trial number: UMIN000017125.

Decompression surgery and intraoperative radiation therapy (IORT) for metastatic spinal tumors

20515

Background: Metastatic spinal tumors often cause spinal cord compression and jeopardize the quality of life of the patients much. To decrease the local symptomatic recurrence rate, we have been adding IORT to decompression surgery. Methods: For those patients whose life expectancy was more than 6 months were eligible for this treatment. Posterior decompression by laminectomy of the involved vertebrae was performed. Following decompression, the patient was irradiated the lesions intraoperatively with electrons generated from Microtron by shielding the spinal cord with lead plate. The central aspects of the vertebrae were irradiated by scattered electrons detouring from the edge of the lead shield up to 40% of the administered dose. Following IORT, posterior instrumentation was performed. External beam radiotherapy might be added pre- and/or postoperatively when considered necessary. Results: 108 patients were treated between 1992–2005. There were 58 males and 50 females. Age ranged from 26 to 85 with a median of 62.5. By primary sites, 26 breast, 24 kidney, 18 colorectum, 17 lung 12 prostate and 11 thyroid cases were included. Irradiated spines were cervical in 6, thoracic in 76, and lumbar/sacral in 27. Overall median follow-up period was 12.7months. Median IORT dose was 20Gy (range 15–26Gy) and median electron energy was 16MeV (range 11–22MeV). There were 37 cases with preoperative RT and 41 cases with postoperative RT. Overall median survival time was 14.5months (breast 15.3, kidney 22.6, colorectum 5.7, lung 6.2, prostate 31.6, thyroid 60.6months). Neurological response rate was 73.1%. Ambulatory rates were 87.0% for success and 80.6% for rescue by Klimo's definition(2005). There were only 8 symptomatic relapses (7%). As for major complications, only one myelopathy has been observed. Conclusions: Decompression surgery and IORT for metastatic spinal tumors with impending spinal cord compression was a promising treatment modality with excellent local control and neurological response rate and with minimal toxicity especially for those patients with long-term prognosis.

No significant financial relationships to disclose.

Relationship between the follicular cells and marginal layer cells of the anterior pituitary

In the anterior pituitaries of adult rats of both sexes, follicular cells resemble marginal layer cells in fine structure. Numerous occurrences of cilia were electronmicroscopically confirmed on the free surface of both cells. The absence of secretory granules, the poor development of endoplasmic reticula and abundant free ribosomes and polysomes are the other coincidental cytological properties between both cells showing the immaturity. Thus, the two cells seem to be intimately related. The follicular cells may play an important role in the mitotic activity of the gland. Cilia and microvilli on the free surface of follicular cells are not easily changed by some experimental conditions.