EUS Evaluation Research Articles

Comparing per-pass performance of 2 types of needles for EUS-guided fine-needle biopsy sampling of pancreatobiliary masses in a randomized trial

EUS-guided fine-needle biopsy sampling (EUS-FNB) has largely replaced FNA for tissue diagnosis of pancreatobiliary mass lesions. However, the optimal number of passes required for the diagnosis of malignancy is not clear. We aimed to compare the per-pass performance of 2 types of fine-needle biopsy (FNB) needles for the detection of malignancy. One hundred fourteen patients referred for EUS evaluation of solid pancreatobiliary mass lesions underwent randomization between biopsy sampling with a Franseen needle and a 3-prong tip needle with an asymmetric cutting surfaces. Four passes of EUS-FNB were taken from each mass lesion. Two pathologists blinded to needle type analyzed the specimens. The final diagnosis of malignancy was made based on FNB specimen pathology, surgery, or a follow-up of at least 6 months after EUS-FNB. The sensitivity of EUS-FNB to diagnose malignancy was compared between the 2 groups. The cumulative sensitivity of detection of malignancy by EUS-FNB was calculated after each pass in each arm. Other characteristics of the specimens including cellularity and blood contents were also compared between the 2 groups. In the primary analysis, lesions categorized as suspicious on EUS-FNB were considered nondiagnostic for malignancy. Ninety-eight patients (86%) had a final diagnosis of malignancy, and 16 patients (14%) had benign disease. Four passes of EUS-FNB with the Franseen needle detected malignancy in 44 of 47 patients (sensitivity, 93.6%; 95% confidence interval [CI], 82.5-98.7) and with the 3-prong asymmetric-tip needle in 50 of 51 patients (sensitivity, 98%; 95% CI, 89.6-99.9; P= .35). Two passes of EUS-FNB detected malignancy with a sensitivity of 91.5% (95% CI, 79.6-97.6) with the Franseen needle and 90.2% (95% CI, 78.6-96.7) with the 3-prong asymmetric-tip needle. The cumulative sensitivities at pass 3 were 93.6% (95% CI, 82.5-98.6) and 96.1% (95% CI, 86.5-99.5), respectively. Samples collected with the Franseen needle had significantly higher cellularity than samples collected with the 3-prong asymmetric-tip needle (P< .01). However, no difference as found between the 2 types of needles in term of specimen bloodiness. No significant differences were found in the diagnostic performance of the Franseen needle versus the 3-prong asymmetric-tip needle in patients with suspected pancreatobiliary cancer. However, the Franseen needle yielded higher cellularity of the specimen. Two passes of EUS-FNB are required to detect malignancy with at least 90% sensitivity with either type of needle. (Clinical trial registration number: NCT04975620.).

Evaluation of EUS Guided Sampling for Hypervascular Pancreatic Masses

Evaluation of EUS Guided Sampling for Hypervascular Pancreatic Masses

Comparison of Endoscopic Ultrasound-Guided Fine-Needle Aspiration with Fine-Needle Biopsy for Solid Gastrointestinal Lesions: A Randomized Crossover Single-Center study

Abstract Background/Aims The purpose of this study was to compare the results of endoscopic ultrasound guided fine-needle aspiration (EUS-FNA) and fine-needle biopsy (FNB) performed at the same site in a single session in the same patient. Methods Consecutive patients with solid gastrointestinal lesions referred for EUS evaluation underwent EUS-FNA and FNB using 22G needles with three and two passes, respectively, in the same session. Patients were randomized to one group having EUS-FNA first followed by EUS-FNB, while other group had EUS-FNB first followed by EUS-FNA. Results Total 50 patients (31 male) of mean age 56.58 ± 14.2 years and mean lesion size of 2.6 (±2) cm were included. The Kappa agreement for final diagnosis for FNA and FNB was 0.841 and 0.61, respectively. The sensitivity and specificity of FNA versus FNB were 85.19 versus 62.96% and 100 versus 100%, respectively, in comparison with final diagnosis. Conclusion Both EUS-FNA and FNB are equally safe when compared between the two techniques simultaneously in same lesion. EUS-FNA is better than FNB in terms of sensitivity, diagnostic accuracy, and tissue yield for solid GI lesion. However, the specificity and positive predictive value were equally good for both the modalities.

Sensitivity, Specificity of Vessel Involvement in Pancreatic Head Adenocarcinoma by Imaging Modality per Treatment Effect

Background: In patients with pancreatic adenocarcinoma, the accuracy of identifying vascular involvement via EUS and MDCT remains unclear, especially in the setting of neoadjuvant therapy. Methods: We conducted a retrospective analysis of patients who underwent a pancreaticoduodenectomy between 2012 and 2016 at Advent Health Orland Hospital. Sensitivity, specificity, positive predictive value and negative predictive value of MDCT and EUS with respect to vessel involvement (SMV, PV, SMA) in a given treatment setting (no treatment, neoadjuvant chemotherapy, neoadjuvant chemotherapy/radiation) were analyzed. Results: In the setting of no treatment, MDCT has the highest sensitivity, specificity, PPV, NPV in the evaluation of the SMA: 22%, 94%, 50%, and 83% respectively. In the setting of no treatment, EUS has the highest sensitivity, specificity, PPV, NPV in the evaluation of the SMV: 33%, 95%, 33% and 95% respectively. The modality with the highest specificity in the assessment of PV involvement is intra-operative evaluation regardless of treatment setting. In the setting of neoadjuvant therapy, either EUS or intra-operative evaluation is preferred over MDCT for the evaluation of the SMA, SMV and PV. Discussion: In the setting of no treatment, the SMA is best evaluated via MDCT, the SMV via EUS, and the PV is best evaluated intra-operatively.

S1100 Comparison of EGD to EGD With EUS in Evaluation of Sub-Epithelial Lesions of the Upper GI Tract

S1100 Comparison of EGD to EGD With EUS in Evaluation of Sub-Epithelial Lesions of the Upper GI Tract

Common bile duct size in malignant distal obstruction and lumen-apposing metal stents: a multicenter prospective study.

Background and study aims Feasibility of EUS-guided choledochoduodenostomy (EUS-CDS) using available lumen-apposing stents (LAMS) is limited by the size of the common bile duct (CBD) (≤ 12 mm, cut-off for experts; 15 mm, cut-off for non-experts). We aimed to assess the prevalence and predictive factors associated with CBD size ≥ 12 and 15 mm in naïve patients with malignant distal biliary obstruction (MDBO). Patients and methods This was a prospective cohort study involving 22 centers with assessment of CBD diameter and subjective feasibility of the EUS-CDS performance in naïve jaundiced patients undergoing EUS evaluation for MDBO. Results A total of 491 patients (mean age 69 ± 12 years) with mean serum bilirubin of 12.7 ± 6.6 mg/dL entered the final analysis. Dilation of the CBD ≥ 12 and 15 mm was detected in 78.8 % and 51.9 % of cases, respectively. Subjective feasibility of EUS-CDS was expressed by endosonographers in 91.2 % for a CBD ≥ 12 mm and in 96.5 % for a CBD ≥ 15 mm. On multivariate analysis, age ( P < 0.01) and bilirubin level ( P ≤ 0.001) were the only factors associated with both CBD dilation ≥ 12 and ≥ 15 mm. These variables were poorly associated with the extent of duct dilation; however, based on them a prediction model could be constructed that satisfactorily predicted CBD size ≥ 12 mm in patients at least 70 years and a bilirubin level ≥ 7 mg/dL. Conclusions Our study showed that at presentation in a large cohort of patients with MDBO, EUS-CDS can be potentially performed in three quarters to half of cases by expert and less experienced endosonographers, respectively. Dedicated stents or devices with different designs able to overcome the limitations of existing electrocautery-enhanced LAMS for EUS-CDS are needed.

A243 A RETROSPECTIVE REVIEW OF THE RADIOGRAPHIC DIAGNOSIS AND SURGICAL RESECTION RATES OF PANCREATIC SEROUS CYSTS

Abstract Background Pancreatic cystic lesions are increasingly identified in persons undergoing abdominal imaging. Serous cystic neoplasms (SCNs) have a very low risk of malignant transformation. Resection of SCNs is not recommended in the absence of related symptoms. The accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) to identify SCNs is not known and may impact clinical care. Aims To evaluate the accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) for the diagnosis of SCN. To see how this can impact the decision to resect suspected SCNs. Methods Retrospective cohort study of patients from the University Health Network with suspected SCNs from 2017–2020 who underwent either a CT or MRI of the abdomen. Reports noting pancreatic cystic lesions were identified and reviewed. Only cases with suspected SCNs were included. Clinical (age, sex, symptoms, treatment) and radiographic (type of imaging, reported cyst characteristics) data was collected. Pathology was reviewed for all cases where the cysts was biopsied or resected during follow-up. The gold standard for the diagnosis for SCN was pathology of resected specimen or EUS-guided biopsy cytopathology showing no evidence of a mucinous lesion, CEA level below 10ug per L and amylase level below 50 U/L. Results 163 patients were included in the study. 99 (61%) were female and 98 (60%) underwent CT scan. EUS-guided biopsy was performed in 24 (15%) of patients and 8 (5%) had surgical resection. Multidisciplinary review was performed in 6 of the 8 cases that went to surgery. Of the resected specimens, 5 (63%) were SCN, 1 was a mucinous cystic lesion, 1 was a neuroendocrine tumor and 1 was a carcinoma. Two patients underwent EUS evaluation prior to surgical resection. In one case SCN was resected when EUS reported an undetermined cyst type. Reasons for surgical resection were: the diagnosis of serous cyst was not definitive (n=5), symptoms (n=2), and high-risk mucinous cystic neoplasm identified on EUS (n=1). Of 30 patients with pathology available, 15 (50%) were confirmed to have a SCN. CT and MRI had a sensitivity, specificity, positive predictive value and negative predictive value of 93%, 25%, 52% and 80%, respectively. Conclusions Surgical resection for SCN lesions is driven by diagnostic uncertainty after cross-sectional imaging. Multidisciplinary review and EUS evaluation may improve diagnostic accuracy and should be considered prior to surgical resection of possible SCN lesions. Funding Agencies None

Preoperative EUS evaluation of the response to neoadjuvant therapy for gastric and esophagogastric junction cancer is correlated with survival: A single retrospective study of 97 patients.

Background and Objectives:The European Society for Medical Oncology suggests performing EUS staging for esophagogastric junction and gastric cancers to further assess the T and N stages. The use of EUS after neoadjuvant therapy (NT) is still under debate. We aimed to evaluate the contribution of EUS after NT to staging, therapeutic choices, and prognosis prediction.Subjects and Methods:In 97 patients with esophagogastric junction and gastric cancers who received NT (chemotherapy or radiochemotherapy) followed by carcinologic surgery, EUS was performed before (uT, uN) and after (yuT, yuN) NT. We compared the results of EUS staging after NT (yuT and yuN) and final histology (ypT and ypN). We analyzed the correlation between overall survival (OS), disease-free survival (DFS), and the objective and subjective responses to NT evaluated by EUS (comparison of uT and yuT and uN and yuN with OS and DFS).Results:EUS staging detected metastasis that went undetected by computed tomography in 16% of metastatic patients. The accuracy between EUS after NT and postoperative pathological findings was 44.4% (34.2%; 54.7%) for T stage and 49.3% (37.5%; 61.1%) for N stage. On multivariate analysis, OS had significantly correlated with the objective response to NT. In the case of a response to NT, the median OS was 64.77 months, and in the case of stable disease, the median OS was 22.9 months (P = 0.01).Conclusion:EUS after NT can be used for staging. Despite its moderate accuracy, the evaluation of the response to NT by EUS seems to be correlated with patient prognosis.

S2924 Ruptured GIST Mimicking Hemosuccus Pancreatitis

INTRODUCTION: Gastrointestinal stromal tumors (GIST) are the most common non-epithelial tumors occurring in the gastrointestinal tract. Even though they are usually solid, they can appear as cystic lesions on imaging leading to a difficult diagnosis. We present a case of a GIST that was initially diagnosed as a pancreatic pseudocyst after extensive work-up. CASE DESCRIPTION/METHODS: A 61-year-old man with no past medical history presented to the ED with abdominal pain after sustaining blunt trauma to the abdomen. Abdominal CT showed a 16 cm left upper quadrant mass with central necrosis and perigastric adenopathy, but no other imaging to compare (Figure 1). During EUS evaluation a thick ring with a central cystic core was noted between the stomach and tail of pancreas. Given this location, traumatic pseudocyst was thought likely. Although the thick wall was somewhat unusual, FNA results were consistent with pseudocyst. PET scan was then performed showing a cystic mass with circumferential heterogenous and mildly increased FDG activity but no adenopathy, supporting a diagnosis of pseudocyst (Figure 2). Unfortunately, the patient was lost to follow up.Eight months later, the patient came to the ED with epigastric abdominal pain associated with black tarry stools. He was tachycardic and the abdomen was distended and tender. Laboratory workup revealed a Hb of 7.1. A CT scan showed the large heterogeneous, cystic mass suggestive of hemorrhagic content as well as ascites (Figure 3). He was admitted to ICU, received 2 units of blood and started on IV pantoprazole. A paracentesis retrieved 1.75 L of hemorrhagic fluid which led to an initial diagnosis of Hemosuccus Pancreatitis. He was not deemed a surgical candidate due to the lesion location and poor nutritional status. A percutaneous catheter was inserted for symptomatic relief and a CT guided biopsy of the wall of the cystic mass was performed. The pathology results were consistent with GIST. DISCUSSION: EUS is a valuable method for evaluation of GISTs by assessing its morphology however, due to the heterogenous appearance, diagnosis can be challenging. Moreover, FNA can yield false negative results due to inadequate amount of tissue, especially if central necrosis is present. This patient's missed diagnosis eventually led to clinical worsening where further work-up was pursued to reveal the definitive diagnosis. GISTs should be considered in your differential despite exhaustive work-up as it may evade diagnosis due to its heterogeneity in morphology and presentation.Figure 1.: Abdominal CT scan on first admission showing a 16 cm enhancing left upper quadrant mass with central necrosis and perigastric adenopathy.Figure 2.: PET scan showing a cystic mass with circumferential heterogenous and mildly increased FDG activity but no adenopathy.Figure 3.: Abdominal CT scan on second admission showing the large heterogeneous, cystic mass suggestive of hemorrhagic content.

Beware of the sandman! False “sand dollar sign” can be misleading during EUS-directed transgastric intervention in Roux-en-Y gastric bypass patients

Patient 1, a 63-year-old woman with Roux-en-Y gastric bypass (RYGB) presented with upper abdominal pain. A CT scan showed gastric remnant wall thickening. An EUS-directed transgastric intervention (EDGI) was attempted, and the presumed excluded stomach was identified under endosonographic view by use of the “sand dollar sign” (A). However, a fluoroscopic view after injection of contrast material showed that the sand dollar sign was the descending colon (B). A repeated EUS evaluation of the true gastric remnant showed diffuse wall thickening (A), and EUS-FNA revealed gastric adenocarcinoma; thus, the sand dollar sign was deceptive. Sand dollar signGastrointestinal EndoscopyVol. 93Issue 2PreviewRegarding “Beware of the Sandman! False ‘sand dollar sign’ can be misleading during EUS-directed transgastric intervention in Roux-en-Y gastric bypass patients,”1 we agree that the sand dollar sign may not be uniformly visualized; however, any visual aid must be used concurrently with other data. Understanding relevant GI anatomy is paramount. In conventional Roux-en-Y gastric bypass, the stomach is divided, and a loop of jejunum is anastomosed to the gastric pouch. The gastric remnant maintains its anatomic position within the abdominal cavity and the gastric antrum, which gives rise to the sand dollar sign2 (Fig. 1), and remains close to midline in the area of the 11th or 12th rib (Fig. 2). Full-Text PDF

EUS-guided fine-needle core liver biopsy with a modified one-pass, one-actuation wet suction technique comparing two types of EUS core needles.

Background and study aims We compared the diagnostic yield and specimen adequacy in EUS-guided parenchymal biopsies between two types of EUS 19 G core needles. Patients and methods This is a retrospective study of 420 patients at two tertiary medical centers in Florida with unexplained abnormal liver associated tests were referred for EUS evaluation of biliary obstruction and pancreatic pathology. EUS-guided liver biopsy (EUS-LB) was performed at the same session after biliary obstruction was excluded. We compared intact specimen length (ISL), total specimen length (TSL), complete portal triads (CPT) and adverse events (AE). Welch’s T and Tukey tests were used for ISL, TSL and CPT. Results A total of 210 patients underwent EUS-LB using a Franseen needle, 210 patients using a fork-tip needle. Median patient age was 52 years (15.63) and 238 (56.7 %) were female. The fork-tip needle had a mean ISL of 2.7 (1.1 SD) cm, TSL of 6 cm (2.1 SD), and mean 19.5 CPT (8.5 SD) Abdominal pain occurred in 35 patients (17 %) post-procedure and was managed with supportive care. Two patients required intravenous (IV) narcotic administration. Subcapsular hematomas occurred in 1 (0.5 %) patients. The Franseen needle had a mean ISL of 3.1 cm (1.3 SD), TSL of 6.5 cm (2.6 SD), and mean of 24 CPT (8.8 SD). Abdominal pain occurred in four patients (2 %) post-procedure, which resolved in all patients after IV narcotic administration. Subcapsular hematomas occurred in 1 (0.5 %) and bile leak in 1(0.4 %) patients. Conclusions Use of the Franseen needle resulted in better liver core samples than that obtained with a fork-tip needle.

Role of Endoscopic Ultrasound to Assess and Manage Portal Hypertension

AbstractPortal hypertension leads to the development of varices along the gastrointestinal tract. Endoscopy plays an important role in the diagnosis and management of varices. Endosonography (EUS) enables visualization and permits access to varices and veins outside the gastrointestinal tract. EUS has emerged as an important tool, with the ability to identify vascular changes, treat gastric and ectopic varices, perform portal pressure measurements, portal venography, and intrahepatic shunt placement. This review discusses the role of endoscopy and the emerging role of EUS in evaluation and management of portal hypertension.

Su1315 DIFFERENCES IN THE DIAGNOSTIC YIELD BETWEEN EUS GUIDED FINE NEEDLE ASPIRATION (FNA) AND CORE BIOPSY (FNB) NEEDLES IN THE EVALUATION OF SUBEPITHELIAL LESIONS IN THE UPPER GASTROINTESTINAL TRACT

Establishing the histological diagnosis of subepithelial lesions (SEL) can be challenging. Even with rapid on-site cytology (ROSE), the diagnostic yield of EUS-FNA is low (40-65%) as core tissue is often required for ancillary studies such as immunohistochemistry (IHC) stain. Newer EUS-FNB needles are designed to obtain core tissue. This study aimed to compare the diagnostic yield of conventional FNA needles with the newer FNB needles in EUS guided tissue acquisition of SEL in the upper gastrointestinal tract. A prospectively collected database on all patients who were referred for EUS guided tissue acquisition of SEL in the upper GIT over 10 years was retrospectively reviewed. All EUS FNA/FNB procedures were performed without ROSE, and all material from the needles were placed into formalin for direct histological examination. The conventional group included specimens obtained from the 22G and 25G FNA needles and 25G reverse bevel needle. The FNB group included specimens from the 20G or 22G reverse bevel needle. The final diagnosis was based on either surgical specimens or from repeat FNA or FNB specimens with at least 6 months of clinical follow up. Specimens from 178 SEL taken from 166 patients, of which 100 were by FNB needles and 78 by FNA needles. There were no differences in demographics, lesion size and location of the lesion along the upper GIT tract between the group. The needle caliber used in each group as well as the diagnoses are summarized in Table 1. The diagnostic accuracy (86/100 vs 45/78; P<0.001) and ability of perform IHC (70/100 vs. 28/78; P<0.001) were substantially higher with FNB than FNA needles. The number of passes were similar in both groups (FNB=2.2± 0.8 vs 2.3±0.9; P=0.61). Of the non-diagnostic cases (n=47), 29 (61%) were smaller than 15mm, and were suspected to be lipomas (n=22), leiomyomas (n-18), pancreatic rest (n=5) or duplication cysts (n=2) based on EUS evaluation. No patients reported or were re-admitted due to pain, bleeding or perforation. Even with a similar number of needle passes and no ROSE, FNB needles achieved a higher diagnostic accuracy than FNA needles for EUS guided tissue acquisition of SEL, suggesting that FNB is the needle of choice for SEL.

Su1425 IMPACT OF EUS GUIDED GASTRO-GASTROSTOMY TO FACILITATE FURTHER ENDOSCOPIC INTERVENTIONS IN PATIENTS WITH ROUX-EN-Y GASTRIC BYPASS: MORE THAN JUST EDGE!

The altered anatomy after Roux-en-Y gastric bypass (RYGB) restricts endoscopic access and prevents routine intervention to the excluded stomach, duodenum and pancreatico-biliary tract. EUS guided gastro-gastrostomy (EGGG) using a lumen-apposing mental stent (LAMS) has recently been reported to allow successful EUS-directed transgastric ERCP (EDGE). The potential interventions via EGGG, however, can be broader. The aim of this study is to evaluate the indication, safety, and clinical success of EGGG interventions in the upper GI tract. A prospectively collected database of RYGB patients referred for evaluation and treatment of suspected luminal or extraluminal pathology, in or around the duodenum and/or excluded stomach over a 15-month period was retrospectively reviewed. All patients underwent EGGG using an electrocautery enhanced LAMS delivery system (“Hot” Axios, Boston Scientific), followed by required interventions as indicated. After the relevant intervention, the LAMS was removed and the fistula was closed at the discretion of the endoscopists. The median follow-up was 6.3±1.9 months. 17 consecutive RYGB patients (66.9±3.4years; 16F:1M) underwent EGGG to facilitate endoscopic evaluation and/or intervention for suspected biliary stone on imaging (n=9), suspected biliary stricture with jaundice (n=3), bile leak (n=1), pancreatic mass (n=2), and need for PEG insertion (n=2). Technical and clinical success rates of EGGG were 100%. There were no complications. Mean procedure time was 40±5 minutes. All patients had a 20 mm diameter LAMS except one treated with a 15 mm due to unavailability of a 20 mm. The required interventions were performed during the same session in 7 (41%) patients, and were delayed in the remaining for a mean of 3.4±0.3 weeks. The post-EGGG interventions included EUS +/- fine needle aspiration (n=14), therapeutic ERCP (n=11), and PEG insertion (n=2). EUS evaluation after EGGG altered the management in 5/14 (35%): EUS-guided FNA confirmed carcinoma (n=2) and chronic pancreatitis (n=1), and EUS avoided unnecessary ERCP after excluding choledocholithiasis (n=2). All endoscopic interventions (stone extraction=9, biliary stent=4; FNA/FNB=3, PEG insertion=2) were successful without complications. The LAMS was removed at the time of intervention in 13/16 (81%) patients. Three (23%) received immediate fistula closure with over-the-scope clips. No weight gain was reported after EGGG except for the 2 patients with PEG feeding. The median number of procedures for EGGG was 2, and the mean duration for the second intervention was 32±3 minutes. In RYGB patients, EGGG via LAMS provided a safe, effective and reversible approach for endoscopic evaluation and intervention in the upper GI and pancreatico-biliary tracts.

EUS-guided 22-gauge fine needle biopsy versus single-incision with needle knife for the diagnosis of upper gastrointestinal subepithelial lesions: a randomized controlled trial.

Background and study aims EUS-FNA has suboptimal accuracy in diagnosing gastrointestinal subepithelial tumors (SETs). EUS-guided 22-gauge fine needle biopsy (EUS-FNB) and single-incision with needle knife (SINK) were proposed to increase accuracy of diagnosis. This study aimed to prospectively compare the diagnostic accuracy and safety of EUS-FNB with SINK in patients with upper gastrointestinal SETs. Patients and methods All adult patients referred for EUS evaluation of upper gastrointestinal SETs ≥ 15 mm in size were eligible for inclusion. Patients were randomized to undergo EUS-FNB or SINK. Lesions were sampled with a 22-gauge reverse beveled core needle in the EUS-FNB group and by a conventional needle-knife sphincterotome and biopsy forceps in the SINK group. Patients were blinded to the technique used. The primary outcome was diagnostic accuracy. Secondary outcomes included adverse events, histological yield and procedure duration. Study enrollment was terminated early due to poor recruitment. Results A total of 56 patients (31 male (55.37 %); mean age, 67.41 ± 12.70 years) were randomized to either EUS-FNB (n = 26) or SINK (n = 30). Technical success was 96.15 % and 96.66 %, respectively. The majority of lesions were gastrointestinal stromal tumors (51.78 %). No significant difference was found between EUS-FNB and SINK in terms of diagnostic accuracy for a malignant or benign disease (76 % vs. 89.28 %, respectively; P = 0.278). The rate of adverse events (none severe) was also comparable (7.69 % vs. 10 %, respectively; P = 1.0) including two abdominal pain episodes in the EUS-FNB group compared to two delayed bleeding (one requiring hospitalization and radiologic embolization) and 1 abdominal pain in the SINK group. Conclusion EUS-FNB and SINK are equally effective techniques for upper gastrointestinal SETs sampling. SINK can be associated with mild to moderate delayed bleeding.

EUS and EUS-guided FNA/core biopsies in the evaluation of subepithelial lesions of the lower gastrointestinal tract: 10-year experience.

Background and Objective:The widespread use of colonoscopy has led to an increasing number of subepithelial lesions (SELs) being detected in the lower gastrointestinal (GI) tract. This study aimed to analyze the utility of EUS and its role in the management of lower GI SELs.Patients and Methods:Records of all patients who were referred for lower EUS evaluation of a SEL at a tertiary center between 2007 and 2018 were retrospectively reviewed after IRB approval. Data collection included patient/lesion characteristics, technical details of procedure, and pathology results.Results:A total of 47 patients underwent EUS examinations for the evaluation of 49 suspected SEL in the lower GI tract (2 patients had 2 SELs each). Out of the 49 suspected lesions, the most frequent location was in the rectum (30/49, 61.2%). EUS showed extraluminal compression in 2 cases (2/49, 4.1%) and intraluminal lesions were identified in 40 cases (40/49, 81.6%). In 7 patients (7/49, 14.3%), no lesion could be identified by EUS. Twenty (20/49, 40.8%) SELs were malignant or had malignant potential. Twenty-six EUS-guided fine-needle aspirations (FNAs) and 14 EUS-core biopsies were performed. EUS-FNA alone was able to correctly diagnose 15/26 (57.7%) of the lower SELs. When EUS-guided fine needle biopsies (FNB) were performed during the same procedure, the final diagnosis was confirmed in 21/26 (80.8%) cases. There was only one procedure-related complication caused by use of narcotics.Conclusion:EUS-guided FNA/FNB are feasible and safe techniques for assessing lower GI SELs and provide valuable information regarding lesion characteristics and their malignant potential with high diagnostic accuracy.

1973 Management of Duodenal NET With Significantly Low Hemoglobin Level on a Jehovah’s Witness Patient

INTRODUCTION: Neuroendocrine tumors (NETs), historically known as carcinoid tumors, can arise throughout the gastrointestinal tract. However, duodenal NETs are very rare; the incidence is only 0.19 / 100,000 in the US. We present a patient who identifies as a Jehovah’s witness presenting with acute on chronic anemia and occult gastrointestinal bleeding due to a bleeding mass which was biopsied and confirmed as a duodenal NET. CASE DESCRIPTION/METHODS: A 69 year-old African American female, Jehovah’s witness, with medical history of end stage renal disease on hemodialysis and anemia of chronic disease who was brought to the hospital for asymptomatic acute on chronic anemia with a hemoglobin of 5.6 g/dL (baseline 9–10 g/dL). Rectal exam revealed melena. Patient underwent upper endoscopy which revealed a 2 cm duodenal bulb mass which was biopsied and pathology revealed neuroendocrine tumor. Patient had elevated serum gastrin level of 250 pg/mL and chromogranin A level of 1963 ng/mL. Octreotide scan confirmed radiotracer uptake in the duodenum and in no other areas. The patient refused blood products adamantly and was managed with darbepoetin alfa. Her hemoglobin gradually trended up several months later to 10 g/dL. For her NET, she was referred to a tertiary center for EUS, for staging and surgical evaluation. DISCUSSION: Duodenal NETs can be divided upon proliferative activity, (well differentiated and poorly differentiated) as well as upon hormonal capabilities (gastrinoma, somatostatinoma, nonfunctional, and paragangliomas). Most patients are incidentally diagnosed during endoscopy or present with late complications of an indolent tumor. Carcinoid syndrome only occurs in less than 10 % cases, when there is metastasis to the liver. Diagnosis is based upon histological staining for neuroendocrine tissue, such as chromogranin and synaptophysin along with checking for proliferative activity with Ki-67 staining. Our patient’s biopsy confirmed well differentiated neuroendocrine tumor, positive for the above markers and low Ki-67 staining. Serum chromogranin A is elevated in 80% of NETs, as in this case. Gastrin level was below 1000 pg/mL, ruling out a functional tumor. CT and octreotide scan excluded any metastasis. NETs which are nonfunctional, without metastasis, and are less than 1 cm can be endoscopically resected. Our patient’s mass was 2 cm, and therefore she was sent for surgical evaluation. Her hemoglobin improved gradually with erythropoietin therapy and her outcome did not change despite her beliefs.

1335 Unchewed Food: The Enemy of Lumen-Apposing Metal Stent Placement in EUS-Gallbladder Drainage

INTRODUCTION: Lumen-apposing metal stents (LAMS) represent a novel therapeutic endoscopic tool for the treatment of acute cholecystitis in high-risk surgical patients via transluminal EUS guided gallbladder (GB) drainage with reported 92-98% success rates. We describe a patient's successful EUS guided drainage and subsequent clinical deterioration after food related LAMS occlusion. CASE DESCRIPTION/METHODS: A 63-year-old man with extensive cardiopulmonary disease, GB hydrops, chronic cholecystitis and prior course of decompression with percutaneous cholecystostomy tube (PTC), was re-evaluated for worsening post-prandial abdominal pain. A CT showed a hydropic GB with layering stones and sludge, concerning for cholecystitis. Semi-urgent decompression with IR cholecystostomy tube vs. EUS-GB drainage was suggested because of his poor surgical candidacy. The patient declined PTC due to reduced quality of life and lack of symptomatic relief in the past. A linear EUS evaluation showed a distended, thick walled GB (12 cm in size) with sludge and debris. A cholecystoenterostomy via doppler EUS was created, followed by deployment of a 15 mm LAMS stent with immediate drainage of copious purulent bile. A 7 Fr × 7 cm double pigtail stent was placed across the LAMS. Despite a technically successful procedure, the patient did not experience clinical improvement. A follow up CT demonstrated decreased GB distention, appropriate LAMS position and related intraluminal GB gas; yet increased GB wall thickening, pericholecystic fluid, and fat stranding in the perihepatic region were consistent with worsening acute cholecystitis. A repeat EGD was performed to ensure proper LAMS location and patency. Large unchewed food pieces in the duodenal bulb and an at least partially occluded LAMS, due to food-debris, were discovered. The LAMS and GB lumen were cleared of food debris using a combination of forceps and water irrigation. The patient was placed on a full liquid diet and subsequently demonstrated clinical improvement. DISCUSSION: EUS-guided GB drainage with LAMS placement is a viable alternative to cholecystectomy for high risk surgical candidates when performed in clinical centers of expertise. Procedural success is high, yet lack of clinical improvement may require further evaluation for possible LAMS occlusion. We describe a case of lack of improvement due to documented occlusion of the LAMS related to poorly chewed food. Dietary counseling for patients post LAMS placement may be beneficial.

Accuracy of EUS and CEH EUS for the diagnosis of pancreatic tumours

Objectives: The main objective is to compare the accuracy of EUS and CEH EUS for the diagnosis of pancreatic cancer (PC). The secondary objective is to evaluate the accuracy of EUS FNA and to determine to what extent EUS and CEH EUS findings are affected by endosonographer subjectivity.Methods: A prospective single-centre study was conducted in patients with pancreatic lesions detected on CT. The patients were examined by EUS, CEH EUS and EUS FNA. The obtained results were compared with the final diagnosis that was based on cytology and further clinical findings and on histopathological findings from subjects who underwent surgery. A second reading of the EUS and CEH EUS images was performed by the endosonographer, who was blinded to clinical data of patients.Results: We examined 116 patients, 73 had a final diagnosis of PC, 14 had NETs and 20 had other tumours. The sensitivity, specificity, NPV, PPV, and accuracy of EUS for diagnosis of PC were 83.1, 62.5, 83.1, 70.7 and 78.6%, for CEH EUS 94.5, 61.7, 84.1, 84 and 84.1% and for EUS FNA 87.6, 91.2, 95.5, 77.5 and 88.8, respectively. The inter-observer agreement for EUS marker of PC was good (κ = 0.75), and that for CEH EUS was average (κ = 0.59 for arterial phase and κ = 0.68 for washout in venous phase).Conclusion: CEH EUS is a non-invasive method that allows more accurate identification of PC than EUS. The subjectivity of CEH EUS evaluation is worse than that of EUS but acceptable.

Endoscopic Ultrasound Elastography for Evaluation of Lymph Nodes: A Single Center Experience.

Background and Aim The differentiation between malignant and benign lymph nodes (LNs) is important for tumor staging, for detection of prognosis, and for selection of the best treatment strategy in many cancers. On B-mode EUS, there are some known criteria that suggest the malignant nature of LNs; these criteria may be found in benign LNs. The aim of the work is to evaluate the effectiveness of elasticity score and SR to differentiate between benign and malignant LNs. Patients and Methods The study was designed as a retrospective study that included 40 patients with abdominal or mediastinal LNs, either associated with primary masses or isolated, referred for EUS evaluation. Elasticity scores and SR were determined during the examination and finally, EUS-FNA was done at the end of the procedure. Results In this 2-years study, 40 patients were enrolled (24 malignant; 16 benign). There were 23 males and 17 females. Their mean age was 52.5 years (range: 28–77). ES alone had a specificity of 87.5%, sensitivity of 41.7%, PPV of 83.3%, NPV of 50%, and accuracy of 60%. Based on the ROC curve analysis results, the best cut-off level of SR to obtain the maximum area under the curve (AUC) was 6.7 with a specificity of 99.9%, sensitivity of 57.1%, PPV of 99.9%, NPV of 64%, and accuracy of 77.5%. Conclusion The use of elasticity score and SR increases the reliability of differentiation between benign and malignant LNs and can decrease the number of unnecessary biopsies.