Faculty Bibliography

INTRODUCTION: Endoscopic submucosal dissection (ESD) and endoscopic full-thickness resection (EFTR) are therapeutic alternatives to surgery for resection of colon and rectal lesions. In regards to large colon and rectal polyps and tumors, both ESD and EFTR have high en bloc resection rates and low recurrence rates, but are limited by training, procedure length, stability, and instrumentation. The Robotic System (RS) is a new robot-assisted endoscopic platform with multiple degrees of freedom allowing improved visualization, dexterity, and tissue manipulation with traction. This is the first U.S. experience assessing the feasibility and safety of robot-assisted ESD and EFTR in resection of distal colon and rectal lesions and its implication for polyps and tumors.
METHOD(S): This is a multicenter retrospective study from five institutions. Patients with distal colon or rectal lesions who underwent either ESD or EFTR with the RS were included. Each patient's clinical history, endoscopic findings, procedural records, and pathology records were reviewed.
RESULT(S): Forty-one patients underwent either ESD or EFTR with the RS for distal colon or rectal lesions, with an average total resection time of 135.0 minutes (s 62.8, n = 24). On average, lesions were 9.3 cm from the anal verge (range: 2 cm to 17 cm, n = 35) and were 30.0 mm in max diameter (range: 9 to 77 mm, n = 28). There were 13 (31.7%) neoplasms and 23 (56.1%) adenomatous polyps; other lesions included inflammatory polyps, diffuse nodular lymphoid hyperplasia, and granulation tissue-all were suspicious for malignancy. Neoplasms included 11 adenocarcinomas and 2 GISTs. Adenomatous polyps included 11 tubular adenomas and 11 tubulovillous adenomas. Twenty-nine out of 34 patients (85.3%) with either adenomatous polyps or adenocarcinoma were successfully removed with the RS alone. Of these, 23 (79.3%) demonstrated clean margins on pathology. Post-endoscopic complications included rectal pain and bleeding.
CONCLUSION(S): This report demonstrates a role of robotic endoscopy for the safe and effective treatment of natural orifice endoscopic surgical resection, with its benefits including traction and triangulation. As endoscopic surgery in the form of ESD evolves, refinement of the tools and techniques of the robotic platform will allow endoscopists to have shorter learning curves and resection of distal colon and rectal polyps and tumors to have higher negative margin rates, potentially allowing more endoscopists the ability to perform ESD

Background: Lumen-apposing self-expandable metal stents (LAMS) have transformed the management of pancreatic fluid collections over the last two decades. There has since been significant interest in expanding the utility of LAMS for additional therapies such as the management of benign luminal strictures. However, there remains little data on their efficacy and safety when used for this indication. The goal of this study was to define the technical success, clinical success, and complication rates of LAMS when used in the management of benign strictures Methods: This was a retrospective multicenter evaluation of the safety, efficacy, and long-term clinical durability of LAMS in the treatment of benign strictures. The study took place between June 2018 and November 2019. Data collection included demographic information, indication, stent size, use of concurrent balloon dilation including dilation diameter, stent stabilization technique, intra-procedure and post-procedure complications, clinical improvement, and post-procedure follow up outcomes.
Result(s): 30 patients underwent placement of LAMS for a benign luminal stricture, with one having two stents placed during the index procedure at separate areas of stenoses resulting in a total of 31 stents placed. In total, 19 stents were 15 x 10 mm and 12 stents were 20 x 10 mm. No intra-procedural complications were noted. The technical success of deployment was 100%. Clinical resolution of symptoms was present in 25 (83%) patients. Of the patients who experienced clinical improvement, 17 underwent stent removal after an average of 6.4 weeks, and clinical recurrence occurred in 7 (41%) patients. The mean time to recurrence of symptoms after stent removal was 7 weeks. Univariate subgroup analysis revealed 15 x 10 mm stents were associated with clinical improvement (OR 12.86, 95% CI: 1.27-130.57, p 0.031). Each patient who did not clinically improve developed pain (3) or stent migration (2). In total 11 (37%) patients developed minor post-procedure adverse event. Stent migration was seen in 5 (17%) cases. Bleeding and pain were noted in 1 (3%) and 7 (23%) patients, respectively. Ulceration was found in 4 patients.
Conclusion(s): LAMS is a durable, safe option for patients with benign luminal strictures. Overall technical success was 100% and clinical success was 83%. The data also suggests better clinical outcomes with 15 x 10 mm stents, when compared to 20 x 10 mm stents. Pain is the most common adverse event but easily managed. [Formula presented]
Copyright

Endoscopic mucosal resection (EMR) is standard of care for removal of large laterally spreading colon polyps, but is often complicated by residual neoplastic tissue which is difficult to resect using standard methods.Large prospective studies from tertiary referral centers report 20% recurrence and 13% incomplete resection (A Moss2015). We introduced a new technique to improve resection of visible residual neoplasia (S Andrawes, 2014).Hot avulsion (HA) is a combination of mechanical traction with simultaneous application of short bursts of cutting current to shear adherent tissue, primarily neoplastic remnants which cannot be removed with a snare due to inability to grasp tissue.Use of hot biopsy forceps has been largely discarded due to concern for perforation,serositis,and delayed bleeding.A change in methodology, which emphasizes mechanical traction and cutting current, has altered the application with minimal risk.The advent of this technique has resulted in reduction of incomplete resection of difficult polyps. We performed a retrospective single center review of all consecutive patients undergoing EMR with adjuctive HA over a 3 year period by a single endoscopist to establish a safety profile for HA.Data collection included patient demographics, polyp size and location, intra and post-procedural complications, and time to onset of complications. A total of 134(55%) women and 110(45%) men, mean age 65, were included with 254 unique polyps (using hot avulsion) removed in 244 colonoscopies.10 patients had more than one polyp removed in a session.Average polyp size was 34mm.Polyps were predominantly in the right colon (69%). No clinically significant intra-procedural bleeding was noted.Two intra-procedure perforations were noted and were treated endoscopically.One was directly related to hot avulsion and treated with endoscopic suturing.The other was related to EMR and was closed using hemostatic clips.One patient(0.4%) was found to have a controlled perforation on CT imaging on day 4 post-op resolved with conservative management.It is unclear if this related to EMR or HA.Clinically significant bleeding requiring intervention occurred in six cases (5 treated with clips and 1 with coagulation).Importantly, there was no evidence of post polypectomy syndrome or transmural injury. Perforation definitely related to HA occurred in one patient and was endoscopically recognized and treated.A single delayed perforation of unclear cause was managed conservatively. Post-procedure bleeding required intervention in six patients and felt to be unrelated to the use of HA. Using appropriate parameters for this method, we conclude that hot avulsion is a safe method for adjunctive removal of visible residual neoplasia. [Formula presented] [Formula presented]
Copyright

The full thickness resection device (FTRD) has become a safe and effective alternative to endoscopic submucosal dissection (ESD) in select cases.One obvious limitation of the FTRD is lesion size, generally less than 20mm.But because polyp size is one of the strongest predictors of advanced histology, many larger lesions may be amenable to a combined approach involving endoscopic mucosal resection (EMR) of the laterally spreading components and full-thickness resection (FTR) of the invasive, non-lifting portion.To our knowledge, a comparison of FTR alone to hybrid EMR + FTR has not been previously published in North America.We report our initial experience using the FTRD alone compared to a hybrid technique combining EMR and FTR in consecutive patients with lesions unresectable by conventional EMR alone. This is a single-center retrospective analysis of prospectively-collected data on consecutive patients who underwent attempted FTR alone or hybrid EMR/FTR.All consecutive patients in whom FTR was attempted during the study were included in this analysis, whether or not FTR was successful.Primary outcomes included technical success, clinical success, R0 resection, and adverse events.Secondary outcomes included procedure duration, adverse events, and subsequent need for surgery.ariataes collected included patient demographics, anticoagulant use, and lesion characteristics. A total of 62 patients underwent either FTR alone (33 patients) or hybrid EMR + FTR(29 patients).The mean lesion size was larger for the hybrid group (36 mm, range 15-60 mm) as compared to FTR alone (19 mm, range 7-40 mm, p<0.01).The FTR procedure was technically successful in 55 of 62 patients (89%).Of these 55 patients, 53 (96%) had R0 resection margins.There was no difference in R0 resection rate among those who underwent hybrid FTR + EMR, (23/24, 96%) versus those who underwent underwent FTR alone (30/31, 97%).In cases of technical failure, R0 resection was not assessed. Two significant adverse events occurred that were directly related to FTR.One patient developed acute appendicitis following FTR of a 15 mm polyp at the appendiceal orifice.One patient suffered an inadvertent perforation.This was immediately identified and successfully closed endoscopically.No bleeding-related adverse events were noted. We demonstrate high rates of technical success, clinical success, R0 resection, and safety.While this is the first study to compare hybrid EMR + FTR to FTR alone from North America, several groups have demonstrated its efficacy and safety elsewhere.In conclusion, our study shows FTR is a safe and effective method to resect large and complex colorectal lesions, and that a hybrid EMR + FTR technique can expand the pool of resectable lesions.Further multi-center prospective studies with the device are needed to assess its long-term safety, efficacy, and curative resection rates. [Formula presented] [Formula presented]
Copyright

Introduction: Pancreatic cystic lesions (PCL) are increasingly identified on cross-sectional imaging. Types include intraductal papillary mucinous neoplasms (IPMN), mucinous cystic neoplasms (MCN), serous cystadenoma (SCA), solid pseudopapillary tumors (SPT) and pseudocysts. Given the risk of malignancy associated with MCN and IPMN with high risk features, accurate PCL diagnosis is essential. Endoscopic ultrasound (EUS) with fine needle aspiration (FNA) of cyst fluid for cytology remains important for the classification of PCL, but is limited by the ability to obtain a sufficient sample and cellularity of fluid. The specificity for malignant cytology is 94%, but sensitivity remains low at 51%. Recently, introduction of a novel microforceps biopsy (MFB) device (Moray Micro Forceps, US Endoscopy, Mentor, OH) has enabled EUS-guided through-the-needle biopsies of PCL through a 19-gauge needle. The aim of this study is to compare the technical success and diagnostic yield for PCL using MFB versus cyst fluid studies alone, along with identifying adverse events associated with MFB.
Method(s): We conducted a retrospective chart review of adult patients with PCL diagnosed by cross sectional imaging undergoing EUS-guided FNA with MFB at 2 tertiary academic centers from November 2016 to November 2019. FNA of PCL was performed and cyst fluid was sent for cytology, carcinoembryonic antigen (CEA) levels, and mutational analysis. Cyst biopsy was performed using MFB.
Result(s): 14 patients were included. 71% were female. Median age was 60 years. Location of cysts in pancreas were head (4), body (6), and tail (4). MFB was technically successful in 12 of 14 cases (yield 86%) including 1 case where no cyst fluid was able to be obtained. There were no reported adverse outcomes (bleeding, pancreatitis, perforation, infection, abdominal pain). MFB diagnosed IPMN in 2 patients, neither of which were identified by cytology but were identified by fluid mutational analysis; MCN in 2 patients, 1 of which was identified by cytology; and SCA in 1 patient where cytology was concerning for a mucinous lesion. Both MFB and cytology were concerning for pseudocyst in 1 patient who ultimately was found to have MCN.
Discussion(s): The technical success of MFB is high and is associated with increased overall diagnostic yield without significant adverse events. For distinguishing PCL types, MFB provided additive diagnostic information to fluid cytology in 4 of 14 patients in our study. Including mutational analysis which identified IPMN in 2 patients where cytology was negative, MFB still provided further diagnostic information in 2 additional patients. This study suggests that the addition of MFB to EUS-guided sampling for cytology, CEA and mutational analysis further augments PCL diagnosis. Future studies should elucidate the role of MFB in combination with mutational analysis. [Formula presented]
Copyright

Introduction: The incidence of duodenal polyps is approximately 1% in retrospective studies and up to 4.6% in one prospective study. Resection of suspected adenomas is recommended as they have a high incidence of development of high grade dysplasia or cancer. Endoscopic resection is associated with high rates of bleeding and perforation. Technical complexity, including involvement of the major papilla need for forward and side- viewing endoscopes, and angulation of the folds makes complete resection challenging. We present a large cohort of duodenal polyp resections including large complex polyps to emphasize complications and to provide recommendation for best clinical practice.
Aim(s): To evaluate the overall safety and efficacy of endoscopic resection of duodenal polyps Methods: A retrospective review of a database of duodenal polyps resected by a single endoscopist (GBH)between June 2016 and November 2018 was performed. The database includes ampullary and non-ampullary and sporadic or genetic syndrome associated (Familial adenomatous polpyposis, Peutz-Jeghers)polyps. Polyps resected by cold biopsy were excluded. This is a descriptive study which includes patient demographics, polyp size and location, resection technique, pathology, complications, and recurrence.
Result(s): The study included 69 procedures to remove 80 polyps total. Size ranged from 0.5cm to 7.0cm and 41 (51%)of the polyps were greater than 2 cm. Endoscopic technique was predominantly snare mucosal resection. Polyps greater than 5cm were generally not resected in a single procedure due to risk of complications and by intention underwent serial resection procedures. Intraprocedural bleeding occurred in 13% of procedures and was controlled entirely endoscopically. Post-polypectomy bleeding occurred in 10% and was managed either endoscopically or conservatively in all cases without surgery. Among larger polyps >2cm, the post-polypectomy bleeding rate was 12.5%. No bleeding was seen in the 22 polypectomy defects closed with clips. A total of three perforations occurred. One required surgical management, one was closed with an over-the-scope clip, and one was closed with a combination of endoscopic sutures and clips. Two patients underwent surgery for incomplete endoscopic resection. Follow up data was available for 27 patients with a mean of 10 months. Excluding the 5 patients who underwent serial procedures to complete resection, there were 7 recurrences out of 22 complete resections (32%).
Conclusion(s): This large series shows that duodenal polyp resection can be successfully performed with appropriate precautions. In contradistinction to the colon, there is little disadvantage to multiple sessions to reduce bleeding risk. Closure of defects with clips when feasible reduces the risk of bleeding. All patients with unclosed defects greater than 2cm should be admitted for overnight observation. [Figure presented][Figure presented]
Copyright

EFTR is a safe and effective for resection of colorectal lesions. One limitation to EFTR, however, is lesion size, typically requiring size less than 2cm. For larger lesions, a hybrid technique using EMR followed by EFTR has been described, though this can be associated with risk for perforation with deployment of the clip into the EMR defect.We present our initial experience with hybrid EMR-EFTR in a series of consecutive patients treated in our center, and compare results to EFTR alone.
Study Design: Single-center retrospective cohort study,comparing consecutive pts who underwent EFTR alone(45%)to those who required EMR with EFTR(55%).All procedures were performed by a single, trained endoscopist.Primary outcomes were technical success,R0 resection with respect to vertical margins,and adverse events.Pt demographics,indication,and lesion/procedural characteristics were collected and analyzed.
Method(s): Standard colonoscopy was performed, advancing to the lesion to be resected.In those who underwent EFTR alone, the periphery of the lesion was marked with a cautery probe in four quadrants. The colonoscope was then withdrawn and a second colonoscope with attached cap,clip,snare,and sleeve was reintroduced and advanced to the lesion.Alligator forceps were used to grasp the lesion and retract it within the cap.Full thickness clip was then deployed followed by snare excision of entrapped tissue.For those in the hybrid group with lesions deemed too large for EFTR,we first performed EMR of the periphery to reduce lesion size and allow for EFTR of the central target area.In all cases, tissue was pinned,measured,and sent to pathology.
Result(s): Primary indication for hybrid EMR-EFTR was lesion size.Mean lesion size in the EFTR group was 16mm and 34mm in the hybrid group. Mean procedure time was 67 minutes in EFTR group and 100 minutes in the hybrid group. Histology confirmed R0 resection in 93% in EFTR group and negative vertical margins were found in 78% of lesions in hybrid group. 2 of 4 patients in the hybrid group with positive vertical margins were due to technical failure.In 1 pt the snare was inadvertently closed,with tissue resection prior to clip deployment resulting in a wall defect. A dual grasping forceps was used to pull the margins of the defect into the cap followed by clip deployment with no adverse sequelae. Complications were relatively rare. 1pt who did not take antibiotic as prescribed developed appendicitis, which required surgery 72hrs after procedure.1pt underwent elective surgery for a T2 cancer. Surgical specimen and lymph nodes showed no evidence of invasive cancer
Conclusion(s): Hybrid EMR-EFTR for colorectal lesions is a safe and effective for resection of lesions that are otherwise too large for EFTR alone.There were no adverse events related to deployment of the clip into tissue with EMR defect.This approach is a alternative to ESD or surgery. [Figure presented][Figure presented]
Copyright

Background: The majority of benign colorectal lesions can be removed using endoscopic mucosal resection techniques. For lesions that are tethered down, nonlifting, invasive or in anatomically challenging locations, advanced endoscopic techniques or surgical resection are typically required. A novel endoscopic full-thickness resection (FTR) device (FTRD, Ovesco Endoscopy, Tuebingen, Germany) was recently approved for use in the United States. Safety and efficacy data on the use of this device have not previously been reported from North America. We present our initial experience with the over-the-scope FTRD in a series of consecutive patients treated in our center. Study Design: We performed a single-center retrospective cohort study, of consecutive patients who underwent endoscopic FTR since its approval in mid-2017. All procedures were performed by a single experienced endoscopist who received training in the use of the device. Primary outcomes were technical success, R0 resection, and adverse events. Patient demographics, indication, and procedural characteristics were collected and analyzed. Method: Routine colonoscopy with an adult colonoscope was advanced to the lesion to be resected. The peripheries of the lesions were marked with a specific cautery probe in four quadrants. The colonoscope was then withdrawn and a second colonoscope with the attached hood, clip, snare, and sleeve was re-introduced and advanced to the lesion. An alligator forceps was used to grasp the lesion to pull it into the hood. The full thickness 'bearclaw' clip was then deployed followed immediately by snare excision of the entrapped tissue. The tissue was pinned, measured, and then sent to pathology. Results: FTR was attempted in a total of 10 patients (Table 1). The primary indication for FTR was non-lifting adenoma (5 patients, 50%). For three patients the indication was an inaccessible location (appendiceal/diverticular), and another two were referred for removal of subepithelial carcinoids. The size of the lesions averaged 16 mm and ranged up to 40 mm in one patient in whom a hybrid resection (EMR + FTR) was performed. The majority of lesions were flat (Paris class IIc or IIa + IIc). Technical success was achieved in nine of ten patients (Table 2). For one 89-year old patient, the procedure was aborted due to difficulties in advancing the FTRD through a tortuous sigmoid colon. Procedure duration averaged 71 minutes. R0 resection of the lesion was achieved in eight patients (pathology pending in one) in whom the FTR device was deployed. One significant adverse event was recorded: the FTR device clip was not deployed prior to full thickness snare incision in one patient resulting in a large perforation. The defect edges were then approximated and the FTR clip was deployed with successful closure of the perforation with no adverse sequela