Yield Of Endoscopic Ultrasound Research Articles

The Role of Endoscopic Ultrasound and Ancillary Techniques in the Diagnosis of Autoimmune Pancreatitis: A Comprehensive Review.

Autoimmune pancreatitis (AIP) is a unique form of chronic pancreatitis with a multifactorial pathogenesis. Historically, it has been classified as type 1 and type 2, according to its clinical and histological features. The diagnosis of AIP is challenging and relies on a combination of clinical, histopathologic, serologic, and imaging characteristics. In the available guidelines, the imaging hallmarks of AIP are based on cross-sectional imaging and cholangiopancreatography retrograde endoscopic findings. Endoscopic ultrasound (EUS) is generally used for pancreatic tissue acquisition to rule out pancreatic cancer and diagnose AIP with limited accuracy. Several papers reported the reliability of EUS for providing informative morphologic features of AIP. Nowadays, the improvement in the resolution of EUS conventional images and the development of new ancillary technologies have further increased the diagnostic yield of EUS: contrast-enhanced EUS and EUS elastography are non-invasive and real-time techniques that strongly support the diagnosis and management of pancreatic diseases. In this review article, we will present the role of conventional EUS and ancillary diagnostic techniques in the diagnosis of AIP to support clinicians and endosonographers in managing this condition.

Comparison of Endoscopic Ultrasound and Transabdominal Ultrasound in the Detection of Gallbladder and Common Bile Duct Microlithiasis.

Endoscopic ultrasonography (EUS) is an emerging method with a wide range of potential uses in gastroenterology, including the detection of bile duct stones and the identification of early ductal alterations in suspected patients. This study was designed to compare the diagnostic yield of EUS and transabdominal ultrasound (TUS) in the detection of gallbladder and common bile duct (CBD) microlithiasis. Patients with biliary colic with normal initial TUS were the subjects of this prospective study. EUS scan was performed on all recruited patients and linear endoscopes were used for the EUS examination. Cholecystectomy and histological analysis were done in patients within two weeks after EUS revealing cholelithiasis whereas the cases of CBD stone/microlithiasis were confirmed by endoscopic retrograde cholangiopancreatography (ERCP). The mean values of all hematological characteristics were independently determined for males and females and then compared using Student's t-test. For statistical significance, a p-value of 0.05 or below was used. A total of 131 patients, including 77 females and 54 males, with a mean age of 38.41 ± 14.78 years were examined. All 78 (59.5%) individuals who had cholecystectomy were found to have gallstones or microlithiasis as successfully diagnosed by EUS. The sensitivity and specificity of EUS were 92.9% and 100%, respectively, for CBD stones and 98.8% and 100%, respectively, for the detection of gallbladder microlithiasis. The agreement between EUS and TUS was fair for CBD stones (κ = 0.214) and very weak for microlithiasis (κ = -0.093). EUSdemonstrates a superior yield over TUSin detecting gallbladder stones and CBD microlithiasis, offering a more reliable diagnostic modality. This was a single-center study.

Clinical predictors of significant findings on EUS for the evaluation of incidental common bile duct dilation

Although EUS is highly accurate for the evaluation of common bile duct (CBD) dilation, the yield of EUS in patients with incidental CBD dilation is unclear. Serial patients undergoing EUS for incidental, dilated CBD (per radiologist, minimum of >6mm objectively) from 2 academic medical centers without active pancreaticobiliary disease or significantly elevated liver function test results were evaluated. Multivariable logistic regression identified predictors of EUS with significant findings and a novel prediction model was derived from one center, internally validated with bootstrapping, and externally validated at the second center. Of 375 patients evaluated, 31 (8.3%) had significant findings, including 26 choledocholithiasis, 1 ampullary adenoma, and 1 pancreatic mass. Predictors of significant findings with EUS included age of≥70 years (odds ratio [OR], 3.7; 95% confidence interval [CI], 1.5-10.0), non-biliary-type abdominal pain without chronic pain (OR, 6.1; 95% CI, 2.3-17.3), CBD diameter of≥15mm or≥17mm with cholecystectomy (OR, 6.9; 95% CI, 2.7-18.7), and prior ERCP (OR, 6.8; 95% CI, 2.1-22.5). A point-based novel clinical prediction model was created: age of≥70 years= 1, non-biliary-type abdominal pain without chronic pain= 2, prior ERCP= 2, and CBD dilation= 2. A score of<1 had 93% (development) and 100% (validation) sensitivity and predicted a<2% chance of having a significant finding in both cohorts while excluding the need for EUS in ∼30% of both cohorts. Conversely, a score of≥4 was >90% specific for the presence of significant pathology. Less than 10% of patients undergoing EUS for incidental CBD dilation had pathologic findings. This novel, externally validated, clinical prediction model may reduce low-yield, invasive evaluation in nearly one-third of patients.

The Diagnostic Yield of Endoscopic Ultrasound in Asymptomatic Patients with Unexplained Dilated Common Bile Duct, or Double Duct Sign with Normal Transaminase a Retrospective Study from a Single Urban-based University Endoscopy Center.

Common bile duct dilatation alone or double duct sign (both CBD and dilated pancreatic duct dilatation) and abnormal liver enzymes are highly predictive of biliary disease. This can be identified on ultrasound (US), CT scan, and/or magnetic resonance cholangiopancreatography (MRCP). Unexplained dilatation on imaging might warrant endoscopic ultrasound (EUS) to identify any occult causes. Supporting literature about the importance of using EUS in these conditions is evolving with no clear evidence-based approach to evaluate asymptomatic dilated ducts.We aim to investigate the diagnostic yield of EUS in unexplained CBD dilatation or double duct sign with normal liver enzymes. A retrospective data analysis was conducted from January 2015 to October 2021 on asymptomatic patients with a dilatated CBD of 7 mm or more and 9 mm if the patient had a cholecystectomy history or double duct sign with normal liver enzymes. 32 EUS procedures were indicated for unexplained dilated CBD or double duct sign on imaging with normal liver enzymes. 23 had CBD dilatation alone (72 %), and 9 had a double duct sign (28 %). 20 of the included patients were females (63 %), and 12 were males (37 %), with a mean age of 63.8 ± 17 and 68.2 ± 14 years old, respectively (p = 0.424). The diagnosis after EUS in CBD dilatation alone showed a yield of 56 % as follow; no pathology in 10 (44 %), sludge in 9 patients (39 %), CBD stone in 3 (13 %), malignant stricture in 1 (4 %) (Fig. 1). On the other hand, EUS in those with double duct signs showed a diagnostic yield of 55 %; no pathology in 4 (45 %), pancreatic head adenocarcinoma in 3 patients (33 %), Biliary stone in one patient, and malignant CBD stricture in one patient (11 % each) (Fig. 2). Unexplained CBD dilatation or Double duct sign on imagining in patients with normal liver enzymes should warrant further investigation with EUS to avoid missing serious pathological conditions such as stones, sludge, stricture, or a mass.

Impact of EUS in liver transplantation workup for patients with unresectable perihilar cholangiocarcinoma

Background and study aimsFor a highly selected group of patients with unresectable perihilar cholangiocarcinoma (pCCA) liver transplantation (LT) is a treatment option. The Dutch screening protocol comprises non-regional lymph node (LN) assessment by endoscopic ultrasound (EUS) and whenever LN metastases are identified, further LT screening is precluded. The aim of this study is to investigate the yield of EUS in patients with pCCA who are potentially eligible for LT. MethodsIn this retrospective, nationwide cohort study, all consecutive patients with suspected unresectable pCCA who underwent EUS in the screening protocol for LT were included from 2011-2021. During EUS, sampling of a ‘suspicious’ non-regional LN was performed based on the endoscopists discretion. The primary outcome was the added value of EUS, defined as number of patients who were precluded from further screening due to malignant LN. ResultsA total of 75 patients was included in whom 84 EUS procedures were performed, with EUS guided tissue acquisition confirming malignancy in LN in 3/75 (4%) patients. In the 43 who underwent surgical staging conform the protocol, non-regional LN were identified in 6 (14%) patients. Regional LN were found in 7 patients in post-LT resected specimens. ConclusionsOur current EUS screening for the detection of malignant LN in patients with pCCA eligible for LT shows a limited but clinically important yield. EUS with systematic screening of all LN stations, both regional and non-regional and sampling of ‘suspicious’ lymph nodes according to defined and set criteria could potentially increase this yield.

Diagnostic and therapeutic strategies for colorectal tumor with positive muscle-retracting sign.

Endoscopic submucosal dissection (ESD) for colorectal tumors with positive muscle-retracting (MR) sign often results in incomplete resection or discontinuation owing to the difficulty of submucosal dissection. The present study aimed to evaluate the usefulness of endoscopic ultrasonography (EUS) in diagnosing the MR sign and performing ESD using the pocket-creation method (PCM). Thirty-six cases of colorectal tumors with positive MR sign during ESD between January 2015 and December 2021 were retrospectively reviewed. Cases were divided into two groups: 1) the conventional method (CM) group, comprising 29 cases, and 2) the PCM group with seven cases, in which preoperative EUS and ESD using PCM were performed. Treatment outcomes were compared between the groups. The diagnostic yield of EUS for the MR sign was evaluated among large sessile tumors >20 mm in which preoperative EUS was performed. Histologic diagnosis was adenoma or Tis carcinoma in 12 cases (33%), T1 carcinoma in 18 cases (50%), T2 carcinoma in four cases (11%), and unevaluable in two cases (6%). The sensitivity and specificity of the EUS-MR sign for large sessile tumors were 87.5% and 83.3%, respectively. ESD was achieved in all cases in the PCM group, although it was discontinued in eight cases (28%) in the CM group. There were significant differences between the PCM and CM groups in en bloc resection (100% vs. 48%, p = 0.013) and R0 resection rates (71% vs. 31%, p = 0.049). The MR sign can be predicted by preoperative EUS, and ESD using PCM allows en bloc resection.

The role of rectal endoscopic ultrasonography plus fine needle aspirartion and fine needle biopsy in pelvic masses.

The diagnostic role of endoscopic ultrasound (EUS) guided fine needle aspiration (FNA) and fine needle biopsy (FNB) of pelvic masses has not been well established. We aimed to evaluate the diagnostic accuracy of EUS plus FNA/FNB in suspected local recurrence of pelvic masses. All consecutive patients with a history of lower gastrointestinal and pelvic mass undergone EUS-FNA/FNB were included in the study. In total 34 patients who underwent EUS-guided FNA or FNB of a perirectal mass were enrolled. The sampled lesion was a mass in 22 patients (64.7%) and a lymph node in 10 patients (29.4%). The univariate logistic regression analysis for diagnostic accuracy showed lesion size as a significant predictor of diagnostic accuracy [odds ratio (OR), 1.61; 1.08-2.27; P = 0.02]. Diagnostic sensitivity was 100% (71.5-100%) with EUS-FNB and 75% (34.9-96.8%) with EUS-FNA ( P = 0.12); specificity was 100% in both groups ( P = 1.0). Sample adequacy was 94.1% in the whole cohort, with 20/20 adequacy rate (100%) in the EUS-FNB group and 12/14 (85.7%) in the EUS-FNA group ( P = 0.28). This is the first study demonstrating the diagnostic yield of EUS plus FNA/FNB in patients with pelvic masses comparing the two needles. Our results highlight the relevance of this technique, especially in undefined masses during oncological follow-up.

Spectrum of Diagnosis and Yield of Endoscopic Ultrasound Guided Fine Needle Aspiration Cytology

Endoscopic ultrasound gives high resolution images of the mediastinum and abdominal organ and improves visualization for obtaining tissue sample for cytology. In our study 112 subjects underwent EUS guided FNAC, out of them 51 were diagnosed as carcinoma (45.5%), 15 as tuberculosis (13.39%), reactive adenitis is 13 (11.6%), other benign disease is 27 (24.1%). So overall diagnosis we made in (106/112) (94.6%). 6 (5.3%) were inconclusive. We suggest that EUSFNAC should be the first line investigation for suspected mediastinal and intra-abdominal malignant masses.

Comparison of EUS and ERCP-guided tissue sampling in suspected biliary stricture.

BackgroundEndoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) are commonly used diagnostic modalities in biliary strictures. We compared the diagnostic yield of EUS and ERCP-based tissue sampling in intrinsic biliary strictures without extrinsic mass outside the bile duct.MethodsA total of 85 patients who underwent ERCP and EUS for diagnosis of suspected biliary strictures confined to the bile duct were analyzed retrospectively at Samsung Medical Center, Seoul, Korea, between 2010 and 2018.ResultsSeventy-one patients were diagnosed with malignancy and 14 patients were diagnosed with benign strictures. EUS-based tissue sampling was more sensitive and accurate than ERCP-based tissue sampling (p = 0.038). The overall sensitivity and accuracy were 67.6% (95% confidence interval (CI) 56.1–77.3) and 72.9% (95% CI 62.7–81.2) for ERCP-based sampling, and 80.3% (95% CI 69.6–87.9) and 83.5% (95% CI 74.2–89.9) for EUS-based sampling, respectively. EUS-based sampling was superior to ERCP-based sampling in distal bile duct strictures (accuracy: 87.0% vs. 72.5%, p = 0.007), but not in perihilar strictures. In cases without intraductal mass, EUS-based tissue sampling was also superior to ERCP-based sampling (accuracy: 83.3% vs. 69.7%, p = 0.029), but not in cases with mass.ConclusionEUS-based tissue sampling was superior to ERCP-based method in intrinsic biliary stricture with no mass outside the bile duct, particularly in those without intraductal mass or those with strictures located in distal bile duct. Therefore, EUS-based sampling should be considered for making a pathological diagnosis of suspected distal bile duct strictures even in lesions without definite mass.

The role of endoscopic ultrasound in evaluating patients with bile duct dilation of unclear etiology.

Bile duct dilation (BDD) of unclear etiology is a common indication for further imaging via endoscopic ultrasound (EUS). We aimed to assess the yield of EUS in determining BDD etiology in patients with prior non-diagnostic imaging studies. A retrospective chart review was performed at a single, tertiary-care university hospital for patients referred for EUS for BDD with or without pancreatic duct dilation (PDD). EUS-guided fine needle aspiration (FNA) was performed if a focal lesion was identified. Cases with an etiology of BDD diagnosed or strongly suggested by prior imaging were excluded. EUS findings believed to represent a structural cause for BDD included a wide range of pancreaticobiliary and luminal pathology as well as patients' clinical factors. In total, 307 patients were identified. Findings to explain BDD were found by EUS in 213 patients for a diagnostic yield of 69.4%. Patients with jaundice were significantly more likely to receive a diagnosis by EUS than those without (78.8% vs 55.3%, P < 0.01). Notably, 8.1% of patients with normal liver function test (LFT) had a EUS-diagnosed malignancy. Patients' age, narcotic use, concurrent PDD and prior cholecystectomy did not appear to influence the EUS yield. EUS continues to play a substantial role in evaluating BDD of unclear etiology, most notably in patients with jaundice. In addition, given that 8.1% of asymptomatic patients without jaundice or abnormal LFT had malignancy diagnosed on EUS, the use of EUS for BDD of unclear etiology remains warranted.

Patients With Unexplained Dilated Pancreatic Duct Have High Risk of Biliopancreatic Malignancy Detected by EUS.

Patients with unexplained dilated common bile duct (CBD) and/or dilated main pancreatic duct (MPD) on noninvasive abdominal imaging tests are often referred for endoscopic ultrasound (EUS) in order to rule out biliopancreatic cancer. The aim of the study was to evaluate the diagnostic yield of EUS in this patient group. A prospective study was conducted. Patients with unexplained dilated CBD and/or MPD on abdominal imaging, who underwent EUS, were enrolled. Fifty-four patients underwent EUS (CBD dilation n=38, MPD dilation n=5 or both n=11). In 31/54 patients (57.4%), EUS revealed pathologic findings. Sixteen patients (29.6%) had EUS evidence of biliopancreatic cancer and 15 patients (27.7%) had benign pathology. Ten (62.5%) of the patients with biliopancreatic cancer had MPD dilation. MPD dilation was significantly associated with malignancy (P=0.017). Patients with unexplained dilated MPD on noninvasive image have a high risk of biliopancreatic malignancy detected by EUS.

Utility of endoscopic ultrasound in idiopathic acute recurrent pancreatitis

Idiopathic acute recurrent pancreatitis (IARP) is defined as at least two episodes of acute pancreatitis with the complete or near-complete resolution of symptoms and signs of pancreatitis between episodes, without...

EUS is superior to secretin-enhanced cholangio-MRI to establish the etiology of idiopathic acute pancreatitis.

Background and study aims The etiology of idiopathic acute pancreatitis (IAP) should always be defined. Our aim was to compare the diagnostic value of endoscopic ultrasound (EUS) versus secretin-enhanced magnetic resonance cholangiopancreatography (S-MRCP) in patients with IAP. Patients and Methods Patients admitted to a single tertiary care University hospital with IAP were invited to participate in the study. Enrolled patients underwent EUS and S-MRCP in a single-blinded comparative study. EUS and S-MRCP were performed no sooner than 4 weeks after discharge. The diagnostic yield of EUS and S-MRCP and demographic variables were included in the analysis. Additional follow-up, results of subsequent serology, radiographic exams, and relevant histological analysis were considered in determination of the final diagnosis. Results A total of 34 patients were enrolled; EUS was normal in six, cholelithiasis was defined in 15, choledocholithiasis in two, pancreas divisum in three, branch-type intraductal papillary mucinous tumor (IPMT) in three, and chronic pancreatitis in five. S-MRCP identified choledocholithiasis in one, divisum in four, branch-type IPMT in three, chronic pancreatitis in two; 24 subjects diagnosed as normal by S-MRCP. Diagnostic correlation between EUS and S-MRCP was slight (kappa = 0.236, 95 % confidence interval: 0.055–0.416). EUS provided a statistically significantly higher diagnostic yield than S-MRCP: 79.4 % (CI95 %: 65 %–94 %) vs 29.4 % (CI95 %: 13 %–46 %) (P = 0.0002). The sensitivity, specificity, and positive and negative predictive values of EUS and S-MRCP were 90 %, 80 %, 96 %, 57 % and 33 %, 100 %, 100 % and 16 %, respectively. Conclusion The diagnostic yield of EUS is higher than S-MRCP in patients with IAP.

Endoscopic ultrasonography can detect a cause in the majority of patients with idiopathic acute pancreatitis: a systematic review and meta-analysis

Idiopathic acute pancreatitis (IAP) has a 25 % pancreatitis recurrence rate. Endoscopic ultrasonography (EUS) may diagnose treatable causes of IAP and hence prevent recurrence. The goal of this systematic review with meta-analysis is to determine the diagnostic yield of EUS and its impact on recurrence. PubMed, EMBASE and the Cochrane Library were systematically searched for English studies on EUS in adults with IAP. The primary outcome was diagnostic yield. Secondary outcomes included recurrence. Methodological quality was assessed using the QUADAS-2 score. Meta-analysis was performed to calculate the pooled diagnostic yield and risk ratio with 95 % confidence intervals (CI) using a random-effects model with inverse variance method. 22 studies were included, with 1490 IAP patients who underwent EUS. Overall diagnostic yield was 59 % (874 /1490; 95 %CI 52 % - 66 %). The most common etiologies were biliary (429 /1490; 30 %, 95 %CI 21 % - 41 %) and chronic pancreatitis (271 /1490; 12 %, 95 %CI 8 % - 19 %). In 2 % of patients, neoplasms were detected (45 /1490; 95 %CI 1 % - 4 %). There was no difference in yield between patients with or without recurrent IAP before EUS (risk ratio 0.89, 95 %CI 0.71 - 1.11). EUS is able to identify a potential etiology in the majority of patients with IAP, detecting mostly biliary origin or chronic pancreatitis, but also neoplasms in 2 % of patients. EUS may be associated with a reduction of recurrence rate. Future studies should include complete diagnostic work-up and preferably include patients with a first episode of IAP only.

Endoscopic ultrasound and fine-needle aspiration for the detection of residual nodal disease after neoadjuvant chemoradiotherapy for esophageal cancer.

Endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) are potential tools for the detection of residual disease after neoadjuvant chemoradiotherapy (nCRT) for esophageal cancer. This study investigated yield of EUS and FNA for detection of malignant lymph nodes (LNs) after nCRT. This was a post hoc analysis of the preSANO trial. EUS was performed 10 - 12 weeks after nCRT. 18F-fluorodeoxyglucose positron emission tomography - computed tomography (18F-FDG PET-CT) was used to guide targeting of suspicious LNs. Consecutive FNA sampling was performed for suspicious LNs identified on EUS and/or PET-CT. EUS nodal staging was compared with histopathological examination of the resection specimen. The primary outcome was the proportion of correctly identified patients with malignant LNs by radial EUS. 101 consecutive patients were included: 79 patients had no malignant LNs, of whom 62 were classified correctly by EUS (specificity 78 %); 22 patients had malignant LNs, of whom 11 were identified (sensitivity 50 %). Six of these patients had ≥ 1 suspicious LN not fulfilling EUS criteria (round, hypoechogenic, > 5 mm). Malignant LNs in falsely negative patients were predominantly located at distal LN stations. Specificity and sensitivity of conclusive FNA outcomes were 100 % (7/7) and 75 % (3/4), respectively. FNA outcome was uncertain in eight patients, half of whom appeared to have malignant LNs. EUS only detected 50 % of patients with malignant LNs 10 - 12 weeks after nCRT. To optimize sensitivity and minimize the risk of missing residual disease, FNA of LNs should be performed even in cases of low endosonographic suspicion.

2811 Outcomes of Endoscopic Ultrasonography (EUS) in Patients Referred for Biliary Dilation Without Significant Biochemical Cholestasis

INTRODUCTION: The diagnostic yield of endoscopic ultrasound (EUS) in non-jaundiced patients with unexplained biliary dilation has been reported to be 6-33%. In our experience, patients with unexplained biliary dilation who use chronic narcotic analgesics might have an even lower diagnostic yield at EUS. However, this correlation has not been well-described as yet. METHODS: We reviewed electronic medical records of patients referred to our center for EUS for the primary indication of unexplained biliary dilation between July 2007 and June 2017. Our database search yielded 767 potential subjects. Exclusion criteria included pancreaticobiliary masses, stones, or calcific chronic pancreatitis seen on prior imaging, a total serum bilirubin &gt;3 mg/dl, or alkaline phosphatase (AP) &gt; 1.5x the upper limit of normal. Data were also separately abstracted on patients with liver tests exceeding the above criteria, yet who had no other exclusion criteria. RESULTS: 41 patients met all inclusion and exclusion criteria. The mean age was 62.4 ± 14.5 years, 37 (90.2%) were female, the mean bile duct diameter at EUS was 12.2 ± 3.8 mm, total bilirubin was 0.6 ± 0.3 mg/dL and AP was 112 ± 62.9 U/L. Most patients (33/41, 80.5%) were symptomatic, reporting abdominal pain or weight loss. A majority (29/41, 70.7%) of patients used oral narcotics. EUS demonstrated choledocholithiasis in 3/29 patients (10.3%) using narcotics and 1/12 (8.3%) not using narcotics. No masses or other relevant pathology was observed. This patient cohort was then combined with 39 additional patients with unexplained biliary dilation who had abnormal liver biochemical tests. Multivariable logistic regression analysis revealed that patients with abnormal liver biochemical tests were 3 times more likely to have positive EUS finding (OR 2.9, CI [1.5,5.7], P = 0.002). Patients using chronic narcotic analgesics were less likely to have positive EUS finding (OR 0.3, CI [0.1, 1.1], P = 0.06). CONCLUSION: A majority of patients referred for EUS to investigate biliary dilation without biochemical cholestasis were women using chronic narcotic analgesics. The diagnostic yield of EUS in this population was low (9.8%) and no neoplasia was found. In contrast, the yield of EUS in patients with biliary dilation and elevated liver tests was strikingly higher at 85%. Use of chronic narcotic analgesics appeared to predict a reassuring EUS examination.

62 Surveillance of High-Risk Individuals for Pancreatic Cancer With EUS and MRI: A Meta-Analysis

INTRODUCTION: Early detection of pancreatic cancer is of interest given the significant morbidity and mortality of this disease. The International Cancer of the Pancreas Screening (CAPS) Consortium guidelines recommend surveillance of high-risk individuals (HRI) with a history of familial pancreatic cancer or carriers of genetic cancer syndrome mutations. Surveillance is typically performed with endoscopic ultrasonography (EUS) and/or magnetic resonance imaging (MRI). The aim of this study is to assess the yield of pancreatic cancer surveillance programs of HRI and compare the yield of EUS and MRI. METHODS: The MEDLINE and Embase (Ovid) databases were searched for prospective studies published up to April 11, 2019 using EUS and/or MRI to screen HRI for pancreatic cancer. Baseline detection of focal pancreatic abnormalities, cystic lesions, solid lesions, high-risk lesions (defined as pancreatic intraepithelial neoplasia grade 3, intrapapillary mucinous neoplasia with high grade dysplasia, or T1N0M0 adenocarcinoma), and pancreatic adenocarcinoma were recorded, as were surgeries performed. Weighted pooled detection rates of outcomes were calculated and were compared between EUS and MRI using random effects modeling. RESULTS: A total of 1109 studies were reviewed and 24 were included in analysis, representing 2112 patients who underwent screening. The weighted pooled rate of focal pancreatic abnormalities detected on baseline screen by EUS (0.34, 95% CI 0.30–0.37) was significantly higher (P = 0.006) than by MRI (0.31, 95% CI 0.28–0.33). There were no significant differences between EUS and MRI for detection of other outcomes, including cysts, high-risk lesions, or pancreatic cancer (Table 1). The overall weighted pooled detection rate of high-risk lesions on baseline screening (regardless of imaging modality) was 0.0090 (95% CI 0.0022–0.016), corresponding to a number-needed-to-screen (NNS) of 111 patients to detect one high-risk lesion. The overall weighted pooled detection rate for pancreatic adenocarcinoma was 0.012 (95% CI 0.0051–0.018) and the surgery rate was 0.054 (95% CI 0.045–0.063) (Table 2). CONCLUSION: Surveillance programs are successful in detecting high-risk precursor lesions with a NNS compatible with existing screening and surveillance programs. No differences between EUS and MRI were noted in the detection rate of high-risk lesions or pancreatic cancer, which supports the use of either imaging study in surveillance programs.

Role of Endoscopic Ultrasound in Detecting Pancreatic Cancer Missed on Cross-Sectional Imaging in Patients Presenting with Pancreatitis: A Retrospective Review.

Pancreatic cancer is the fourth leading cause of cancer-related death in the USA. Early detection of pancreatic cancer may help improve patient survival. It has been hypothesized that acute idiopathic or chronic pancreatitis is associated with an increased risk of pancreatic cancer; however, these conditions may also represent an early manifestation of pancreatic cancer, rather than just being risk factors. Endoscopic ultrasound (EUS) is a sensitive diagnostic modality for the detection of small, early-stage pancreatic tumors. The aim of this study was to evaluate the diagnostic yield of EUS for pancreatic cancer in patients with acute idiopathic or chronic pancreatitis when cross-sectional imaging (CT and/or MRI) was negative for a mass lesion in the pancreas. This study was an IRB-approved retrospective chart review conducted for the period of August 2005 to September 2018. Any patient presenting with acute idiopathic or chronic pancreatitis with a CT and/or MRI imaging negative for a pancreatic mass lesion that underwent an EUS during the study period was selected for inclusion. A retrospective review was performed to evaluate the outcomes of patients who had pancreatic cancer diagnosed from an EUS-FNA (fine needle aspiration) sample. Data were collected on patient demographics and clinical characteristics, inclusive of specific post-diagnosis treatment course. An "event rate" was calculated and is defined as the number of positive pancreatic cancer diagnoses on EUS-FNA from all patients presenting with acute idiopathic or chronic pancreatitis who underwent an EUS examination following a CT and/or MRI study negative for pancreatic mass lesion. A total of 565 patients met inclusion criteria, with 30 cases of confirmed pancreatic cancer diagnosed with EUS-FNA from this group. The event rate for EUS diagnosis of pancreatic cancer was 5.3%. The majority of patients (52.0%) diagnosed with cancer were stages I-II. Endoscopic ultrasound should be a routine part of the diagnostic algorithm when evaluating a patient with acute idiopathic or chronic pancreatitis of unclear etiology, particularly when cross-sectional imaging is negative for a mass lesion and clinical suspicion is high for neoplasia. Further prospective studies are needed to evaluate the role of EUS in this setting.

Qualitative and Quantitative Contrast-enhanced Endoscopic Ultrasound Improves Evaluation of Focal Pancreatic Lesions

Endoscopic ultrasound (EUS) is a sensitive method to evaluate the pancreas but its diagnostic capability for several diseases is limited. We compared the diagnostic yield of unenhanced EUS with that of contrast-enhanced EUS for focal pancreas lesions and identified and tested quantitative parameters of contrast enhancement. We performed a prospective tandem-controlled trial in which 101 patients with focal pancreas lesions (48 with masses, 28 with cysts, and 25 with pancreatitis) underwent conventional EUS followed by contrast EUS using intravenous perflutren microspheres. The diagnosis at each stage was scored and compared with a standard (findings from surgical pathology analysis, cytologic, and/or 6-month clinical follow-up evaluations). Quantitative parameters were generated by time-intensity curve analysis. Solid lesions were divided into derivation and testing cohorts for a crossover validation analysis of the quantitative parameters. The primary outcome was diagnostic yield of unenhanced vs contrast EUS in analysis of focal pancreas lesions. Contrast increased the diagnostic yield of EUS from 64% (65/101 lesions accurately assessed) to 91% (92/101 lesions accurately assessed); the odds ratio [OR] was 7.8 (95% CI, 2.7-30.2) for accurate analysis of lesions by contrast-enhanced EUS relative to unenhanced EUS. The contrast increased accuracy of analysis of pancreas masses (OR, 6.0; 95% CI, 1.8-31.8), improving assessment of neuroendocrine and other (non-carcinoma) tumors. Contrast increased the diagnostic yield for pancreas cysts to 96% (27/28) compared with 71.4% (20/28) for unenhanced EUS (P = .02), due to improved differentiation of mural nodules vs debris. Time-intensity curve analysis revealed distinct patterns of relative peak enhancement (rPE) and in-slope (rIS) for different lesions following contrast injection: for adenocarcinomas, values were low rPE and low rIS; for neuroendocrine masses, values were high rPE and normal IS; and for chronic pancreatitis foci, values were normal rPE and low rIS. In the validation cohort, these parameters correctly characterized 91% of lesions and improved yield relative to unenhanced EUS (OR, 10; 95% CI, 1.4-34.0). Contrast-enhanced EUS improves the accuracy of analysis of focal pancreas lesions, compared with unenhanced EUS. Integration of practical quantitative parameters, specifically relative peak enhancement and in-slope, might increase the diagnostic accuracy of contrast EUS. ClinicalTrials.gov no:02863770.

Tu1259 – Yield of Endoscopic Ultrasound and Computed Tomography Scans in the Evaluation of Esophagogastric Junction Outflow Obstruction

Tu1259 – Yield of Endoscopic Ultrasound and Computed Tomography Scans in the Evaluation of Esophagogastric Junction Outflow Obstruction