Faculty Bibliography

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]
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Introduction: EUS-guided FNA and FNB have been stagnating at accuracy levels which falls short of patient and physician hopes. False negative results for malignancy continue to range from 4% (expert centers) to 30%. Multiple passes of the needles often slide along the same tract as the first pass, limiting diagnostic yield. FNA requires 5 passes, fewer for the FNB needles. Rapid on-site cytology may lower the number of passes, but it is logistically and financially challenging, without proving to improve accuracy. Repeated passes bend needles out of shape leading to use of a second needle, with high cost implications. Tumor composition can be a mosaic of desmoplasia, necrosis, cystic areas, and malignant cells. If a needle is in the wrong plane then wrong diagnosis occurs. Often fanning hardly moves the needle. We introduce a new needle prototype to improve diagnostic yield and lower false negatives, with use of a device which has five needles.
Method(s): A multi-pass needle has been designed which ensures five specimens will be from various sites, because the five needles are all penetrating at the same time along different planes within the lesion. This needle apparatus uses the same sheath as a standard 19 gauge needle, but within the sheath it houses a five-lumen plastic tube, which separates between the central 22g needle and the four peripheral 25g needles. The ergonomically-designed handle has a two-phase mechanism which allows the endoscopist to first place the 22g needle within the target lesion, which is the same as the process done today, and to then deploy the four 25g needles, which are pre-bent so as to spread out to a diameter of about one cm, when needles are about 3cm from the scope. The additional needles will each, without fanning, obtain specimens near to the central needle, thus a greater representation of tumor will be obtained, completing the procedure in one pass, with better accuracy due to decreasing false negatives. The two channels for suction apply to the single central needle and to the four peripheral needles. Each needle has its own stylet.
Result(s): The accompanying figure shows the InstaFan, a disruptive technological advance, made to improve EUS biopsies. Three in vivo porcine studies found that the 5 needles delivered resulted in five distinct adequate specimens for pathology diagnosis by the cell block method. Porcine EUS found good visibility of the needles, ease of deployment and no side effects from multiple deployments of the onepass device, both in EUS-guided gastric and duodenal biopsies of porcine pancreas and liver.
Conclusion(s): Future directions of the Onepass will be additional in vivo animal safety studies by additional endoscopists followed by first trials in humans. The goal of the Onepass will be to reduce false negatives, thus increasing optimization of tumor diagnosis. [Formula presented] [Formula presented]
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PURPOSE OF REVIEW/OBJECTIVE:This review highlights the history, recent advances, and ongoing challenges of artificial intelligence (AI) technology in colonic polyp detection. RECENT FINDINGS/RESULTS:Hand-crafted AI algorithms have recently given way to convolutional neural networks with the ability to detect polyps in real-time. The first randomized controlled trial comparing an AI system to standard colonoscopy found a 9% increase in adenoma detection rate, but the improvement was restricted to polyps smaller than 10 mm and the results need validation. As this field rapidly evolves, important issues to consider include standardization of outcomes, dataset availability, real-world applications, and regulatory approval. AI has shown great potential for improving colonic polyp detection while requiring minimal training for endoscopists. The question of when AI will enter endoscopic practice depends on whether the technology can be integrated into existing hardware and an assessment of its added value for patient care.

PURPOSE OF REVIEW/OBJECTIVE:With the intent of maximizing adenoma detection rate (ADR), different devices and colonoscopic innovations have been introduced over the past few years. There are a variety of attachment devices available for use in colonoscopy, all intended to improve ADR. In this review, we evaluate the evidence surrounding the available attachment devices and their impact on ADR. RECENT FINDINGS/RESULTS:Endocuff, Endoring, Transparent cap, G-EYE balloon, and Third Eye Retroscope were all included in this review. Three of the devices, Endocuff, Endoring, and transparent hood or cap, have been shown to increase ADR without significantly altering the use of the colonoscope. Although balloon-assisted colonoscopy is not currently FDA-approved, it has the potential to increase ADR as well. Mechanical enhancement has been shown to complement the current forward-viewing colonoscope, and Endocuff appears to be the most beneficial attachment to improve ADR.

BACKGROUND & AIMS/OBJECTIVE:Mucosal exposure devices improve detection of lesions during colonoscopy and have reduced examination times in uncontrolled studies. We performed a randomized trial of Endocuff Vision vs standard colonoscopy to compare differences in withdrawal time (the primary end point). We proposed that Endocuff Vision would allow complete mucosal inspection in a shorter time without impairing lesion detection. METHODS:Adults older than 40 years undergoing screening or surveillance colonoscopies were randomly assigned to the Endocuff group (n=101, 43.6% women) or the standard colonoscopy group (n=99; 57.6% women). One of 2 experienced endoscopists performed the colonoscopies, aiming for a thorough evaluation of the proximal sides of all haustral folds, flexures, and valves in the shortest time possible. Inspection time was measured with a stopwatch and calculated by subtracting washing, suctioning, polypectomy and biopsy times from total withdrawal time. RESULTS:There were significantly fewer women in the Endocuff arm (P=.0475) but there were no other demographic differences between groups. Mean insertion time with Endocuff was 4.0 min vs 4.4 min for standard colonoscopy (P=.14). Mean inspection time with Endocuff was 6.5 min vs 8.4 min for standard colonoscopy (P<.0001). Numbers of adenomas detected per colonoscopy (1.43 vs 1.07; P=.07), adenoma detection rate (61.4% vs 52%; P=0.21), number of sessile serrated polyps per colonoscopy (0.27 vs 0.21; P=0.12), and sessile serrated polyp detection rate (19.8% vs 11.1%; P= 0.09) were all higher with Endocuff Vision. Results did not differ significantly when we controlled for age, sex, or race. CONCLUSION/CONCLUSIONS:In a randomized trial, we found inclusion of Endocuff in screening or surveillance colonoscopies to decrease examination time without reducing lesion detection. ClinicalTrials.gov no.: NCT03361917.

BACKGROUND AND AIMS/OBJECTIVE:Although screening for Barrett's esophagus (BE) is recommended in individuals with multiple risk factors, the type and number of risk factors necessary to trigger screening is unclear. In this systematic review and meta-analysis, we aimed to assess the relationship between number of risk factors and prevalence of BE. METHODS:Through October 17, 2018, we searched studies that described the prevalence of BE in the general population and based on presence of risk factors that included GERD, male gender, age >50 years, family history of BE and esophageal adenocarcinoma (EAC), and obesity (defined as body mass index >35). Risk of BE based on number of risk factors was assessed using meta-regression while controlling for potential confounders. RESULTS:Of 2,741 studies, 49 were included in the analysis (307,273 individuals, 1,948 with biopsy-proven BE). Indications varied by study. The prevalence of BE for various populations was as follows: low-risk general population: 0.8% (95% CI, 0.6% - 1.1%); GERD: 3% (95% CI, 2.3% - 4%); GERD plus presence of any other risk factor: 12.2% (95% CI,10.2% - 14.6%); family history: 23.4% (95% CI,13.7% -37.2%); age > 50: 6.1% (95% CI, 4.6% - 8.1%); obesity: 1.9% (95% CI, 1.2% - 3%); and male sex: 6.8% (95% CI, 5.3% - 8.6%). Prevalence of BE varied significantly between Western and non-Western populations. In a meta-regression, controlling for the region of the study, age, and gender, there was a positive linear relationship between the number of risk factors and the prevalence of BE. CONCLUSIONS:Results of this study provide estimates of BE prevalence based on the presence and the number of risk factors. These results add credence to current guidelines that suggest screening in the presence of multiple risk factors.