Bronte A. Holt

Wide field endoscopic resection for advanced colonic mucosal neoplasia: current status and future directions.

Most colonic adenomas are ≤ 10 mm and are routinely treated by colonoscopic polypectomy with long-term health benefits. Nonpolypoid lesions ≥ 20 mm, whether sessile or flat and laterally spreading, are forms of advanced mucosal neoplasia that cannot be managed by conventional polypectomy and are often referred for surgery. However, the majority of these lesions when carefully assessed are found to be noninvasive and can be safely and effectively treated by advanced endoscopic techniques including endoscopic mucosal resection or endoscopic submucosal dissection with resultant cost, morbidity, and mortality benefits. Lesion assessment is a critical component. Enhanced imaging methods provide the opportunity for accurate pathological characterization, informing treatment decisions, without the need for previous histologic confirmation. Techniques of advanced endoscopic resection are still in evolution and further improvements, including hybrid techniques, bringing less technically challenging and shorter procedures with superior safety can be reasonably expected in the next decade. Safety is a fundamental consideration. Methods of early recognition of complications, risk stratification, and management pathways are being developed and refined. Standardization, validation, and adoption of these technological developments will improve endoscopic interpretation and therapy and in combination with an increased understanding of adenoma molecular biology, will result in a progressively more individualized lesion-specific endoscopic approach. The future of advanced endoscopic resection in the colon is promising, and the next few years should see the boundaries of endoscopic resection expand well beyond the limits of what we know today.

Carbon dioxide insufflation reduces number of postprocedure admissions after endoscopic resection of large colonic lesions: a prospective cohort study

BACKGROUND Endoscopic resection (ER) for large colonic lesions is a safe and effective outpatient treatment. Postprocedural pain creates concern for perforation and often results in postprocedure admission (PPA). Carbon dioxide (CO(2)) insufflation has been shown to reduce pain scores after routine colonoscopy, but an influence on more critical outcomes such as PPA has not been shown. OBJECTIVE To assess the outcomes of patients undergoing ER for large colonic lesions, comparing those having air versus those having CO(2) insufflation. DESIGN Prospective, observational, cohort study. SETTING Academic, high-volume, tertiary-care referral center. PATIENTS Consecutive patients referred for ER of sessile colorectal polyps ≥20 mm. INTERVENTION ER with air or CO(2). MAIN OUTCOME MEASUREMENTS Rates of PPA, technical outcomes, complication rates. RESULTS ER was performed on 575 lesions ≥20 mm, 228 with CO(2) insufflation. Mean lesion size was 36.5 mm. Lesion and patient characteristics were similar in both groups. The use of CO(2) was associated with a 62% decrease in the PPA rate from 8.9% to 3.4% (P = .01). This was mainly because of an 82% decrease in PPA for pain from 5.7% to 1.0% (P = .006). There were no significant difference in the rates of complications. Multiple logistical regression was performed. The adjusted odds ratio (OR) of PPA (OR 0.39; 95% confidence interval [CI], 0.16-0.95; P = .04) and PPA for pain (OR 0.18; 95% CI, 0.04-0.78; P = .02) in the CO(2) group remained significant. LIMITATIONS Single center, nonrandomized study. CONCLUSION CO(2) insufflation significantly reduces PPA after ER of large colonic lesions, primarily because of reduced PPA for pain. CO(2) insufflation should be routinely used during ER of large colonic lesions.

Prophylactic Endoscopic Coagulation to Prevent Bleeding After Wide-Field Endoscopic Mucosal Resection of Large Sessile Colon Polyps

BACKGROUND & AIMS Clinically significant postendoscopic mucosal resection bleeding (CSPEB) is the most frequent significant complication of wide-field endoscopic mucosal resection (WF-EMR) of advanced mucosal neoplasia (sessile or laterally spreading colorectal lesions > 20 mm). CSPEB requires resource-intensive management and there is no strategy for preventing it. We investigated whether prophylactic endoscopic coagulation (PEC) reduces the incidence of CSPEB. METHODS We performed a prospective randomized controlled trial of 347 patients (mean age, 67.1 y; 55.3% with proximal colonic lesions) undergoing WF-EMR for advanced mucosal neoplasia at 3 Australian tertiary referral centers. Patients were assigned randomly (1:1) to groups receiving PEC (n = 172) or no additional therapy (n = 175, controls). PEC was performed with coagulating forceps, applying low-power coagulation to nonbleeding vessels in the resection defect. CSPEB was defined as bleeding requiring admission to the hospital. The primary end point was the proportion of CSPEB. RESULTS Patients in each group were similar at baseline. CSPEB occurred in 9 patients receiving PEC (5.2%) and 14 controls (8.0%; P = .30). CSPEB was associated significantly with proximal colonic location on multivariate analysis (odds ratio, 3.08; P = .03). Compared with the proximal colon, there was a significantly greater number (3.8 vs 2.1; P = .002) and mean size (0.5-1 vs 0.3-0.5 mm; P = .04) of visible vessels in the distal colon. CONCLUSIONS PEC does not significantly decrease the incidence of CSPEB after WF-EMR. There were significantly more and larger vessels in the WF-EMR mucosal defect of distal colonic lesions, yet CSPEB was more frequent with proximal colonic lesions. ClinicalTrials.gov NCT01368731.

Topical submucosal chromoendoscopy defines the level of resection in colonic EMR and may improve procedural safety (with video)

BACKGROUND Blue dyes such as indigo carmine have become a frequent component of the submucosal injectate for EMR. Confirmation of the correct resection plane and assessment of the resection defect are facilitated by the selective staining of the submucosal layer. Nonstained areas are more difficult to evaluate and may contain inadvertent muscularis propria (MP) injury. The use of topical submucosal chromoendoscopy (TSC) may allow rapid and accurate assessment of these unstained areas and visual recognition of MP injury. OBJECTIVE To evaluate the utility of a novel technique in the assessment of nonstained areas within the post-EMR defect. DESIGN Single-center prospective cohort study. SETTING Academic, tertiary care referral center. PATIENTS A total of 143 patients undergoing wide-field colonic EMR for sessile lesions 20 mm or larger. INTERVENTIONS A standard inject-and-resect EMR technique was applied with indigo carmine blue dye in the injectate. Defects with areas of nonstaining were recorded and examined, and then irrigated with the submucosal injectate by using the blunt tip of the injection catheter. MAIN OUTCOME MEASUREMENTS Detection of additional cases of MP injury by using TSC. RESULTS A total of 147 EMRs were performed. Focal areas of defect nonstaining were seen in 25 of cases (17%), with no MP injury identified on initial examination. After TSC, 2 additional cases of MP injury were identified, and these were successfully managed endoscopically. Intraprocedural recognition of deep resection increased from 4 cases (2.8%) to 6 cases (4.1%), thereby avoiding potential delayed perforation in 2 patients. LIMITATIONS Single-center, nonrandomized study. CONCLUSIONS TSC is simple and effective and rapidly confirms the plane of resection and may improve detection of intraprocedural perforation.

Outcomes after implementing a tailored endoscopic step‐up approach to walled‐off necrosis in acute pancreatitis

The aim of the study was to compare the outcomes of patients with pancreatic or peripancreatic walled‐off necrosis by endoscopy using the conventional approach versus an algorithmic approach based on the collection size, location and stepwise response to intervention.

Advanced mucosal neoplasia of the anorectal junction: endoscopic resection technique and outcomes (with videos).

BACKGROUND EMR at the anorectal junction (ARJ) is technically challenging. Issues of safety and procedural efficacy dictate that surgery is still performed as the primary management for noninvasive lesions in most centers. Modifications to the standard EMR technique may help to address the unique features and achieve safe and curative resection of most lesions. OBJECTIVE To describe an effective and safe, modified EMR technique to remove advanced mucosal neoplasia (AMN) of the ARJ. DESIGN Prospective, observational cohort study. SETTING Academic, tertiary care referral center. PATIENTS Patients undergoing EMR for AMN at the ARJ over 4.5 years, from June 2008 to December 2012. INTERVENTIONS Use of long-acting local anesthetic in the submucosal injectate, endoscopic resection over the dentate line and hemorrhoidal columns, prophylactic antibiotics for resection of lesions at high risk for bacteremia, and cap and gastroscope-assisted resection. MAIN OUTCOME MEASUREMENTS Procedural success and safety. RESULTS Twenty-six patients with lesions involving the ARJ were referred for EMR (males 53.8%, median age 63, median lesion size 40 mm). Two patients went directly to surgery because of an endoscopic diagnosis of adenocarcinoma. EMR was performed in 24 lesions with complete adenoma clearance achieved in 100%. Four patients were admitted to the hospital. Focal adenoma recurrence was seen in 4 of 18 patients (22%) at first surveillance colonoscopy and was managed by snare diathermy resection. No recurrences were found at the second follow-up colonoscopy. Procedural success, adenoma recurrence, and admission rates were similar between EMRs performed at the ARJ and proximal rectum on univariate analysis (all P > .05). LIMITATIONS Single tertiary center, nonrandomized study. CONCLUSIONS Simple modifications to the EMR technique allow safe and effective treatment of AMN at the ARJ on an outpatient basis and should be the first-line management when the risk of invasive disease is low.

The endoscopic management of pancreatic pseudocysts (with videos)

It is therefore considered as first-line treatment.This review highlights the techniques used forendoscopic management of pseudocysts. It provides back-ground into the current definition and the indications forand timing of endoscopic intervention, and it describesthe various drainage techniques, adverse events, recom-mended before- and after-procedure management, andareas of uncertainty.

Endoscopic ultrasound-guided pelvic abscess drainage (with video)

Pelvic abscesses present a serious and challenging management problem. Endoscopic ultrasound (EUS)‐guided drainage provides a safe and effective minimally invasive treatment option. The likelihood of a successful outcome is dependent on appropriate patient selection, drainage technique and postoperative management. This review outlines the evidence behind and procedural steps required for EUS‐guided pelvic abscess drainage.

Training endosonographers in cytopathology: improving the results of EUS-guided FNA

BACKGROUND Although on-site cytopathology services have a significant impact on efficiency and accuracy of EUS-guided FNA (EUS-FNA), the availability of this service is variable. OBJECTIVE To evaluate the impact of an intensive 2-day training program to educate endosonographers in EUS-related cytopathology. DESIGN Pilot study. SETTING Tertiary care medical center. SUBJECTS Six endosonographers (5 male, median age, 35 years) with minimal previous cytopathology exposure comprised the study cohort. METHODS Pre- and posttraining testing was administered. Training commenced with a cytopathology tutorial focusing on 4 performance measures: specimen adequacy, sample interpretation, specimen processing, and preliminary diagnosis. Eight live EUS-FNA cases were then performed, and study participants independently completed 4 questions based on performance measures for each case. The ability to independently smear and stain slides and operate a microscope was additionally assessed after a hands-on tutorial. MAIN OUTCOME MEASUREMENTS Comparison of pretraining and posttraining scores, improvement in performance measures for live cases, and ability to independently handle specimens and operate a microscope. RESULTS Compared with pretraining, mean posttraining test scores improved by 63% from 48 to 78 out of 100. Mean live case performance score was 95%. Performances improved from 89% on day 1 to 100% on day 2. After training, all endosonographers could independently smear/stain slides and operate a microscope. LIMITATIONS Long-term impact is unclear. CONCLUSIONS An intensive 2-day program was effective in training endosonographers in the basics of EUS-related cytopathology. Incorporating basic cytopathology in EUS fellowship curriculum will likely improve diagnostic performance of tissue acquisition procedures.

Endoscopic ultrasound-guided fine needle aspiration or fine needle biopsy: the beauty is in the eye of the beholder

The impact of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) on pancreatic tissue acquisition has been so profound that the technique is regarded as a disruptive innovation [1]. However, EUS-FNA has twomajor limitations: the diagnostic performance is dependent on the availability of a cytopathologist to render rapid onsite evaluation and it doesn’t provide histology, which may be required to establish a conclusive diagnosis when FNA cytology alone is insufficient. The ProCore biopsy needle was developed to overcome these limitations. In this issue of the journal, two randomized trials compare the diagnostic performance of the ProCore and standard FNA needles for tissue acquisition in solid pancreatic mass lesions [2,3]. In the Frenchmulticenter study by Vanbiervliet et al., 80 patients with solid pancreatic masses underwent fine needle biopsy (FNB) using a single pass of the 22G ProCore needle and FNA with two passes of a standard 22G FNA needle, with the two investigations being performed in a randomized order [2]. The specimenswere processed offsite for cytology and histology. There was no difference in diagnostic accuracy (>90% for both needles), and the overall histological quality was superior with the FNA needle. In the second study from South Korea by Lee et al., 116 patients with solid pancreatic masses were randomized to undergo either FNA or FNB using the ProCore or standard FNA needle, with 22G and 25G needles used in the stomach and duodenum respectively [3]. In addition to rapid onsite evaluation, each pass was analyzed for cytology and histology. Similar to the French multicenter study, there was no significant difference between the cohorts in overall diagnostic accuracy (FNB 98.3% vs. FNA 94.8%; P=0.67) or histological accuracy (FNB 82.8% vs. FNA 77.6%; P=0.64). Both randomized trials deliver the samemessage: the diagnostic performance of the ProCore and standard FNA needles are comparable. More importantly, the histological yield of the ProCore needle is not superior to a standard FNA needle. A recent meta-analysis comparing the technical performance of the ProCore and standard FNA needles in 641 patients with pancreatic masses found no significant difference in the diagnostic accuracy between the ProCore and standard FNA needles (88.4% [95%CI 82.4%–93.3%] vs. 79.9% [95%CI 73.6%–85.5%], respectively; P=0.067), or in terms of histological core tissue procurement (75.4% [95%CI 60.2%–87.8%] vs. 75.2% [95%CI 63.2%–85.5%], respectively; P=0.075) [4]. These findings accord with the results of the two randomized trials published in this issue of the journal [2,3]. Inwhat context dowe evaluate these findings and how do we move the discipline of EUS-guided tissue acquisition forward? The answers lie in a critical analysis of historical perspectives and lessons learnt from clinical experience, and reassessment of the technological refinements required to improve procedural outcomes.