FORWARD-VIEWING VERSUS SIDE-VIEWING ENDOSCOPIC EXAMINATION DURING ERCP: PRELIMINARY RESULTS FROM A BLINDED, TANDEM PROSPECTIVE TRIAL

BACKGROUND: Endoscopic Snare Papillectomy (ESP) is a minimally invasive option for the management of noninvasive ampullary adenomas. The primary aim of this study is to determine risk factors for incomplete resection of ampullary adenomas following ESP, as well as the impact of rectal indomethacin and pancreatic duct (PD) stenting on post-papillectomy pancreatitis (PPP).

METHODS: This retrospective multicenter study included consecutive patients undergoing index ESP for ampullary adenomas from 1/2012-9/2020 at two referral centers. Patient demographics, procedural indications, details, adverse events, pathology, and subsequent interventions were collected. Wilcoxon rank-sum test and Fisher’s exact test were used to compare continuous and categorical variables. Stepwise logistic regression was used to identify predictors for residual disease and PPP.

RESULTS: Of 136 included patients, 24 (18%) carried a diagnosis of Familial Adenomatous Polyposis. Overall median adenoma size was 20mm (IQR, 15mm, 25mm) and 47 (35%) adenomas were laterally spreading. Common bile duct extension was seen on pre-procedure EUS or index ERCP in 25 (19%) patients. En bloc resection was used in 77 (57%) patients. Advanced neoplasia was seen in 60% of patients (Table 1). Median duration of surveillance was 899 days (IQR 382, 2041 days). Residual neoplasia was seen in 66 (49%) patients on first surveillance endoscopy, of whom 6 (9%) had biopsy-confirmed residual malignancy. Factors not meeting inclusion threshold during stepwise regression (P<0.20) were adenoma size, location, and presence of periampullary diverticulum. Factors associated with increased risk of residual adenoma were biliary extension (OR 6.87, 95% CI 2.10-22.48) and piecemeal resection (OR 2.32, 95% CI 1.09-4.92) (Table 2). Median number of endoscopic sessions required for successful ampullary adenoma eradication was 1 (IQR 1 session, 2 sessions). Surgical pancreaticoduodenectomy was ultimately required in 13 (10%) patients.

PPP occurred in 20 (15%) patients. Prophylactic PD stent was placed in 122 (90%) patients, of whom 62 (51%) underwent PD stenting alone and 60 (49%) received combination PD stenting and rectal indomethacin. Decreased rates of PPP were seen with PD stenting (OR 0.22, 95% CI 0.06-0.78, P=0.020), but not with rectal indomethacin alone (OR 0.82, 95% CI 0.32-2.12) or in combination with PD stenting (OR 0.49, 95% CI 0.18-1.37).

CONCLUSIONS: Residual adenoma was seen in nearly half of patients with ampullary adenomas after ESP. CBD extension and piecemeal resection were predictive of residual disease. ESP was associated with a 15% rate of PPP, which was lowered by PD stenting. Reduction of PPP was not demonstrated by the addition of rectal indomethacin or indomethacin alone.

Background and aims: Adverse events (AEs) after endoscopic retrograde cholangiopancreatography (ERCP) are not uncommon. Post-ERCP pancreatitis (PEP) is the main AE. Albeit its pathophysiology is not fully understood, thermal injury from biliary sphincterotomy may play an important role and affect other AEs. Therefore, this study evaluates the outcomes of two electric current modes used during biliary sphincterotomy.

Methods: From October-2019 to August-2021, consecutive patients submitted for ERCP with native papilla undergoing biliary sphincterotomy were randomized to either the pure cut (30-50W - WEM S200 and ICC 200 electrosurgical units) or endocut (effect 2 - VIO 300 and VIO 300 electrosurgical units) after transpapillary cannulation in two terciary reference centers. The study was conducted according to CONSORT statements and analysis were performed under intention-to-treat basis. The primary outcome was PEP incidence. Secondary outcomes included intraprocedural and delayed bleeding, infection, and perforation.

Results: 550 patients were randomized (272 for pure cut and 278 for endocut – figure 1). The overall PEP rate was 4.0%, and it was significantly higher in the endocut arm (5.8% x 2.2%, p=0.034 – table 1). Univariate analysis revealed >5 attempts (p=0.004) and endocut mode (p=0.034) as risk factors for PEP. Multivariate analysis revealed >5 attempts (p=0.005) and a trend for endocut mode as a risk factor for PEP (p=0.052). Intraprocedural bleeding occurred more often with pure cut (p=0.018). Delayed bleeding was more frequent with endocut (p=0.047). There was no difference in terms of perforation (p=1.0) or infection (p=0.499) among the groups.

Conclusion: This RCT revealed that endocut is associated with higher rates of PEP and delayed bleeding, whereas pure cut is associated with increased intraprocedural bleeding. As all intraprocedural bleeding were controlled during ERCP, pure cut should be the preferred electrocautery mode for biliary sphincterotomy. Additionally, no more than five cannulation attempts should be performed, as this is also associated with PEP.

Introduction:
Over 500,000 ERCPs are performed annually in the United States. Currently, most endoscopists perform an ERCP with only a side-viewing endoscope (i.e., duodenoscope). We hypothesized that given the non-forward-viewing design of a duodenoscope, there is a significant miss rate of important findings. Therefore, the primary aim of this study was to evaluate differences in clinical findings between a forward-viewing and side-viewing examination during ERCP.

Methods:
We conducted a blinded, tandem, single-center prospective clinical trial at a tertiary academic center (NCT: NCT05627882). Patients undergoing ERCP for standardized indications were recruited. Six credentialed attending gastroenterologists were outcome assessors. Included patients underwent a standard forward-viewing endoscopic examination with one attending. Findings were deemed to be clinically significant (leading to management change) or classified as non-management altering. Results were recorded by a nurse not involved with the study so the answers could not be modified. A second attending, blinded to the forward viewing results, subsequently performed the ERCP with a duodenoscope. Results were recorded in a similar fashion. Continuous data were compared using the two-sample t-test or Wilcoxon rank-sum test and categorical data were compared using the Chi-square or Fisher’s exact test, as appropriate.

Results:
A preliminary trial analysis of 44 included participants was performed. Baseline demographics including co-morbidity history and anticoagulation are shown in Table 1. Forward-viewing endoscopic examination noted more endoscopic abnormalities when compared to side-viewing (56.81% vs 18.18%; P<0.001) – total miss rate of 38.63%. Discordant results were identified in 52.27% of patients (23/44). Clinically significant discrepancies (i.e., practice changing) were noted in 38.64% of patients (17/44), with non-significant differences among 22.73% of patients (10/44) [P=0.109]. No abnormalities were found with duodenoscope examination that were not identified on forward-viewing examination. Of the findings missed on side-viewing examination, 16 were in the esophagus, 8 in the stomach, and 3 in the duodenum. 65% of the practice changing findings were found in outpatient cases. Examples of missed findings included: ulcerated gastric sarcoma, deep ulceration requiring endoscopic clipping, Barrett’s esophagus, as well as esophageal and gastric varices.

Discussion:
Current clinical practice for ERCP traditionally relies solely on examination with a side-viewing endoscope. However, this blinded, tandem prospective trial found a significant 38.63% miss rate when patients underwent forward-viewing examination. These findings suggests that forward-viewing examination may be valuable in addition to use of a duodenoscope during routine ERCP procedures.