The role of molecular analysis in the diagnosis and surveillance of pancreatic cystic neoplasms.

CONTEXT: Molecular analysis of pancreatic cyst fluid obtained by EUS-FNA may increase diagnostic accuracy. We evaluated the utility of cyst-fluid molecular analysis, including mutational analysis of K-ras, loss of heterozygosity (LOH) at tumor suppressor loci, and DNA content in the diagnoses and surveillance of pancreatic cysts. METHODS: We retrospectively reviewed the Columbia University Pancreas Center database for all patients who underwent EUS/FNA for the evaluation of pancreatic cystic lesions followed by surgical resection or surveillance between 2006-2011. We compared accuracy of molecular analysis for mucinous etiology and malignant behavior to cyst-fluid CEA and cytology and surgical pathology in resected tumors. We recorded changes in molecular features over serial encounters in tumors under surveillance. Differences across groups were compared using Student's t or the Mann-Whitney U test for continuous variables and the Fisher's exact test for binary variables. RESULTS: Among 40 resected cysts with intermediate-risk features, molecular characteristics increased the diagnostic yield of EUS-FNA (n=11) but identified mucinous cysts less accurately than cyst fluid CEA (P=0.21 vs. 0.03). The combination of a K-ras mutation and ≥2 loss of heterozygosity was highly specific (96%) but insensitive for malignant behavior (50%). Initial data on surveillance (n=16) suggests that molecular changes occur frequently, and do not correlate with changes in cyst size, morphology, or CEA. CONCLUSIONS: In intermediate-risk pancreatic cysts, the presence of a K-ras mutation or loss of heterozygosity suggests mucinous etiology. K-ras mutation plus ≥2 loss of heterozygosity is strongly associated with malignancy, but sensitivity is low; while the presence of these mutations may be helpful, negative findings are uninformative. Molecular changes are observed in the course of cyst surveillance, which may be significant in long-term follow-up.

A multicenter, U.S. experience of single-balloon, double-balloon, and rotational overtube-assisted enteroscopy ERCP in patients with surgically altered pancreaticobiliary anatomy (with video).

BACKGROUND: Data on overtube-assisted enteroscopy to facilitate ERCP in patients with surgically altered pancreaticobiliary anatomy, or long-limb surgical bypass, is limited. OBJECTIVE: To evaluate and compare ERCP success by using single-balloon (SBE), double-balloon (DBE), or rotational overtube enteroscopy. DESIGN: Consecutive patients identified retrospectively. SETTING: Eight U.S. referral centers. PATIENTS: Long-limb surgical bypass patients with suspected pancreaticobiliary diseases. INTERVENTION: Overtube-assisted enteroscopy ERCP. MAIN OUTCOME MEASUREMENTS: Enteroscopy success: visualizing the pancreaticobiliary-enteric anastomosis or papilla. ERCP success: completing the intended pancreaticobiliary intervention. Clinical success: greater than 50% reduction in abdominal pain or level of hepatic enzyme elevations or resolution of jaundice. RESULTS: From January 2008 through October 2009, 129 patients had 180 enteroscopy-ERCPs. Anatomy was Roux-en-Y: gastric bypass (n = 63), hepaticojejunostomy (n = 45), postgastrectomy (n = 6), Whipple procedure (n = 10), and other (n = 5). ERCP success was 81 of 129 (63%). Enteroscopy success: 92 of 129 (71%), of whom 81 of 92 (88%) achieved ERCP success. Reasons for ERCP failure (n = 48): afferent limb entered but pancreaticobiliary anastomosis and/or papilla not reached (n = 23), cannulation failure (n = 11), afferent limb angulation (n = 8), and jejunojejunostomy not identified (n = 6). Select interventions: anastomotic stricturoplasty (cautery ± dilation, n = 16), stone removal (n = 21), stent (n = 25), and direct cholangioscopy (n = 11). ERCP success rates were similar between Roux-en-Y gastric bypass and other long-limb surgical bypass and among SBE, DBE, and rotational overtube enteroscopy. Complications were 16 of 129, 12.4%. LIMITATIONS: Retrospective study. CONCLUSION: (1) ERCP is successful in nearly two-thirds of long-limb surgical bypass patients and in 88% when the papilla or pancreaticobiliary-enteric anastomosis is reached. (2) Enteroscopy success in long-limb surgical bypass is similar among SBE, DBE, and rotational overtube enteroscopy methods. (3) Referral of long-limb surgical bypass patients who require ERCP to high-volume institutions may be considered before more invasive percutaneous or surgical alternatives.

Multicenter trial evaluating the use of covered self-expanding metal stents in benign biliary strictures: time to revisit our therapeutic options?

BACKGROUND: Covered self-expanding metal stents are being used more frequently in benign biliary strictures (BBS). We report the results of a multicenter study with fully covered self-expanding metal stent (FCSEMS) placement for the management of BBS. AIM: : To prospectively evaluate the efficacy and safety of FCSEMS in the management of BBS. PATIENTS AND METHODS: Patients with BBS from 6 tertiary care centers who received FCSEMS with flared ends between April 2009 and October 2010 were included in this retrospective study.Efficacy was measured after removal of FCSEMS by evaluating stricture resolution on the basis of symptom resolution, imaging, laboratory studies, and/or choledochoscopy at removal. Safety profile was evaluated by assessing postprocedural complications. RESULTS: A total of 133 patients (78, 58.6% males) with a mean age of 59.2±14.8 years with BBS received stents. Of the 133 stents placed, 97 (72.9%) were removed after a mean stent duration of 95.5±48.7 days. Stricture resolution after FCSEMS removal was as follows: postsurgical, 11/12 (91.6%); gallstone-related disease, 16/19 (84.2%); chronic pancreatitis, 26/31 (80.7%); other etiology, 4/5 (80.0%); and anastomotic strictures, 19/31(61.2%). Ninety-four patients were included in the logistic regression analyses. Patients who had indwelling stents for >90 days were 4.3 times more likely to have resolved strictures [odds ratio, 4.3 (95% confidence interval, 1.24-15.09)] and patients with nonmigrated stents were 5.4 times more likely to have resolved strictures [odds ratio, 5.4 (95% confidence interval, 1.001-29.29)]. CONCLUSIONS: FCSEMS for BBS had an acceptable rate of stricture resolution for postsurgical strictures, gallstone-related strictures, and those due to chronic pancreatitis. Predictors for stricture resolution include longer indwell time and absence of migration. Further study is warranted to assess long-term efficacy in a prospective manner with longer than 3-month time of stent indwelling time.

Evaluation of a fully covered self-expanding metal stent with flared ends in malignant biliary obstruction: a multicenter study.

BACKGROUND AND AIMS: Limited data are available regarding fully covered metal stents in the management of malignant distal biliary strictures. The aim of this study was to evaluate the safety of a fully covered self-expanding metal stent (FCSEMS) with flared ends, in treating malignant biliary strictures. We report our long-term retrospective analysis from 6 centers. METHODS: A total of 260 patients (142 males, median age 68 y) underwent endoscopic retrograde cholangiopancreatography with placement of FCSEMS (WallFlex; Boston Scientific, Natick, MA) for the palliation of obstructive jaundice in the setting of pancreatic adenocarcinoma (169), metastatic disease (36), cholangiocarcinoma (23), ampullary cancer (19), or other (13). Patients were evaluated clinically in follow-up and biochemical tests of liver function were obtained. Data were recorded for the following variables: patient survival, duration of stent patency, the need for subsequent biliary intervention, and complications. RESULTS: A total of 266 FCSEMS were placed in 260 patients. There was a median survival of 100 days (range, 7 to 531 d). There was a mean follow-up of 134±118 days (range, 4 to 519 d). Biliary decompression was successful in 252 patients (97%). At the end of the study period, 121 were alive with a patent stent, 65 patients died with a patent stent, 40 patients were successfully bridged to surgery, 8 patients had their patent stent removed and had no need for further stenting, and 18 patients were lost to follow-up. Five patients who had a successfully placed FCSEMS were considered a failure due to the following reason: migration (2), cholangitis (1), stent occlusion (1), and removal for management of proximal biliary obstruction (1). Two additional patients experienced migration that did not require FCSEMS removal or replacement. Stent replacement was required in 10 patients, of whom 6 had a second FCSEMS placed. The remaining 4 were in the failure group and underwent replacement with either uncovered stents or plastic stents. Other complications, managed conservatively, included pain (2), postendoscopic retrograde cholangiopancreatography pancreatitis (4), fever (1), retroperitoneal perforation (1), and postsphincterotomy bleeding (1). The mean patency duration was 328 days (SE 19.04). The patency percentage was 83% at 3 months, 63% at 6 months, and 48.5% at 12 months. CONCLUSIONS: In the management of malignant distal biliary strictures, the fully covered WallFlex stent has acceptable patency and complication rates. Further long-term prospective data are required to confirm this observation.

Polysomy and p16 deletion by fluorescence in situ hybridization in the diagnosis of indeterminate biliary strictures.

BACKGROUND: The diagnosis of indeterminate biliary strictures is limited because of the low sensitivity of cytology. However, an accurate diagnosis of malignancy is critical in the management of patients with suspected biliary malignancy. Testing for chromosomal aneuploidy by fluorescence in situ hybridization (FISH) may increase the yield. OBJECTIVE: To evaluate the diagnostic accuracy of FISH in indeterminate biliary strictures and the additional value of including deletion of 9p21 (p16) in the diagnostic criteria of malignant biliary strictures. DESIGN: Retrospective review. SETTING: Academic medical center. PATIENTS: This study involved 76 consecutive patients who were seen for the evaluation of indeterminate strictures at our institution. These patients were screened, and 50 patients with either a final pathologic diagnosis or ≥ 12 months' conclusive follow-up were included in the analysis. MAIN OUTCOME MEASUREMENTS: Sensitivity, specificity, and area under the curve (AUC) analysis of cytology alone compared with the presence of FISH polysomy versus FISH polysomy and 9p21 deletion. RESULTS: The presence of increased copy numbers (polysomy) of chromosome 3, 7, or 17 by FISH increased the sensitivity of brush cytology from 21% to 58%, and when the presence of 9p21 deletion was included, the sensitivity increased to 89%. The specificity of FISH was 97% (vs 100% for cytology). The accuracy of cytology combined with FISH polysomy (AUC = 0.93) or p16 deletion was significantly greater than the accuracy of cytology alone (AUC 0.6; P < .001) or even cytology combined with FISH polysomy (AUC = 0.77; P ≤ .05). LIMITATIONS: Sample size. There is a relatively high incidence of malignant biliary strictures in the entire cohort but low incidence among primary sclerosing cholangitis patients, and the majority of cancers are cholangiocarcinomas (as opposed to pancreatic). CONCLUSION: FISH significantly improves the diagnostic accuracy of brush cytology in indeterminate biliary strictures. In our series, the addition of 9p21 deletion to FISH polysomy and cytology further improved sensitivity. This suggests that 9p21 deletion may be added to the diagnostic criteria in indeterminate strictures.

Single-operator cholangioscopy in patients requiring evaluation of bile duct disease or therapy of biliary stones (with videos).

BACKGROUND: The feasibility of single-operator cholangioscopy (SOC) for biliary diagnostic and therapeutic procedures was previously reported. OBJECTIVE: To confirm the utility of SOC in more widespread clinical use. DESIGN: Prospective clinical cohort study. SETTING: Fifteen endoscopy referral centers in the United States and Europe. PATIENTS: Two hundred ninety-seven patients requiring evaluation of bile duct disease or biliary stone therapy. INTERVENTIONS: SOC examination and, as indicated, SOC-directed stone therapy or forceps biopsy. MAIN OUTCOME MEASUREMENTS: Procedural success defined as ability to (1) visualize target lesions and, if indicated, collect biopsy specimens adequate for histological evaluation or (2) visualize biliary stones and initiate fragmentation and removal. RESULTS: The overall procedure success rate was 89% (95% CI, 84%-92%). Adequate tissue for histological examination was secured in 88% of 140 patients who underwent biopsy. Overall sensitivity in diagnosing malignancy was 78% for SOC visual impression and 49% for SOC-directed biopsy. Sensitivity was higher (84% and 66%, respectively) for intrinsic bile duct malignancies. Diagnostic SOC procedures altered clinical management in 64% of patients. Procedure success was achieved in 92% of 66 patients with stones and complete stone clearance during the study SOC session in 71%. The incidence of serious procedure-related adverse events was 7.5% for diagnostic SOC and 6.1% for SOC-directed stone therapy. LIMITATIONS: The study was observational in design with no control group. CONCLUSIONS: Evaluation of bile duct disease and biliary stone therapy can be safely performed with a high success rate by using the SOC system.

Is there any difference in outcomes between long pigtail and short flanged prophylactic pancreatic duct stents?

OBJECTIVE: Prophylactic pancreatic duct (PD) stent placement has been shown to reduce the incidence of post-ERCP pancreatitis (PEP) especially in high-risk patients. However, there is no consensus on the best type of PD stent. The purpose of our study was to evaluate the differences in the outcomes between long (>3 cm) pigtail and short (≤3 cm) flanged 4 Fr Freeman Pancreatic Flexi-Stents in preventing PEP. METHODS: We retrospectively reviewed all ERCP procedures performed between 08/01/2006 and 10/01/2007 by one of two experienced endoscopists (>5 years of experience) with the assistance of a trainee. Patient data was collected for indications, risk factors for PEP, type and reason for PD stent, complications, and any mortality. The PD stent was removed endoscopically if it was still in place on abdominal X-ray done 2 weeks post-ERCP. The data was analyzed with Student's t test, Chi-square, and ANOVA tests by using SPSS software version 15.0. RESULTS: Out of a total of 753 ERCP procedures, 179 (23.8%) required either long or short prophylactic PD stents. The incidence of PEP was 3.7% versus 13.6% for long and short stent groups, respectively (p=0.019). Spontaneous stent dislodgement rate was 95.4% versus 81.8% for long and short stent groups, respectively (p=0.007). There was no difference in non-pancreatic complications between the two stent groups. There was no procedure-related mortality. CONCLUSIONS: Long (>3 cm) pigtail PD stent due to their specific design showed better outcomes as compared to short (<3 cm) flanged PD stent in preventing PEP and spontaneous stent dislodgement rates. However, further prospective trials are needed.

Detection of intestinal metaplasia after successful eradication of Barrett's Esophagus with radiofrequency ablation.

BACKGROUND: Radiofrequency ablation (RFA) is an effective means of eradicating Barrett's esophagus (BE), both with and without associated dysplasia. Several studies have documented high initial success rates with RFA. However, there is limited data on IM detection rates after eradication. AIMS: To determine the rate of detection of intestinal metaplasia (IM) after successful eradication of Barrett's esophagus. METHODS: BE patients with and without dysplasia who had undergone RFA were retrospectively identified. Only those who had complete eradication as documented on the initial post-ablation endoscopy, and had minimum two surveillance endoscopies, were included in the analyses. Clinical, demographic, and endoscopic data were collected. Cumulative incidence of IM detection was calculated by the Kaplan-Meier method. RESULTS: Forty-seven patients underwent RFA and had complete eradication of Barrett's epithelium. The majority of patients were male (76.6%), and the mean age was 64.2 years. The cumulative incidence of newly detected IM at 1 year was 25.9% (95% CI 15.1-42.1%). Dysplasia was detected at the time of recurrence in four patients, and all cases were detected at the GE junction in the absence of visible BE. Patients with recurrent IM had longer baseline segments of BE (median, 4 cm vs. 2 cm, p = 0.03). CONCLUSIONS: The rate of detection of new IM is high in patients who have undergone successful eradication of BE by RFA. Additionally, dysplasia can recur at the GE junction in the absence of visible BE. Future studies are warranted to identify those patients at increased risk for the development of recurrent intestinal metaplasia.

Multimedia article: Transvaginal laparoscopic cholecystectomy: laparoscopically assisted.

Natural orifice transluminal endoscopic surgery (NOTES) is considered the new frontier for minimally invasive surgery. NOTES procedures such as peritoneoscopy, splenectomy, and cholecystectomy in animal models have been described. The aim of our experiment was to determine the feasibility and technical aspects of a new endoluminal surgical procedure. After approval from Columbia's IACUC, a transvaginal laparoscopically assisted endoscopic cholecystectomy was performed on four 30 kg Yorkshire pigs. The first step was to insert a 1.5 cm endoscope into the vagina under direct laparoscopic vision. Then the gallbladder was reached and, with the help of a laparoscopic grasper to hold up the gallbladder, the operation was performed. At the end of the procedure the gallbladder was snared out through the vagina attached to the endoscope. There were no intraoperative complications such as bleeding, common bile duct or endo-abdominal organ damage. Total operative time ranged between 110 and 155 min. Based on our experience in the porcine model, we believe that a transvaginal endoscopic cholecystectomy is feasible in humans.

Nonvariceal upper gastrointestinal bleeding.

Nonvariceal upper gastrointestinal bleeding (NVUGIB) is an important condition facing gastroenterologists. The focus of this article is the management of NVUGIB, with a particular emphasis on the endoscopic modalities and techniques that are most effective for various bleeding etiologies. Attention also is given to medical management, risk assessment, and issues pertaining to the timing of endoscopy and need for scheduled second-look endoscopy.

Interobserver agreement for evaluation of imaging with single operator choledochoscopy: what are we looking at?

BACKGROUND: Single operator choledochoscopy is a platform used to assist in the confirmation of diagnosis of biliary lesions. However, there are little data regarding the interobserver agreement of imaging interpretation. Our objective was to assess the interobserver agreement in single operator choledochoscopy interpretation. METHODS: 38 De-identified SPY Choledochoscopy video clips were sent to 7 interventional endoscopists. They were asked to score the videos on presence of four criteria selected by the investigators: growth, stricture, hyperplasia, and ulceration. Observers also chose a final diagnosis from the categories of cancer, hyperplasia, inflammation, or normal. Kappa scores were calculated for the scoring of the four criteria and for the selection of the final diagnosis. RESULTS: The overall interobserver agreement was fair in scoring for the presence of a growth (K=0.28, SE 0.035) and stricture (K=0.32, SE 0.035). Scoring for ulceration was slight to fair (K=0.17, SE 0.035). There was only slight agreement for the presence of hyperplasia (K=0.11, SE 0.035); and presumed final diagnosis based on imaging (K=0.18, SE 0.022). CONCLUSION: The results of this study support the need for an effort to identify and validate cholangioscopy imaging criteria for biliary pathology. This may assist in improving the reliability of the diagnostic value of cholangioscopy as its use becomes more widespread.

Capecitabine and temozolomide (CAPTEM) for metastatic, well-differentiated neuroendocrine cancers: The Pancreas Center at Columbia University experience.

PURPOSE: We evaluated the efficacy and safety of capecitabine and temozolomide (CAPTEM) in patients with metastatic neuroendocrine tumors (NETs) to the liver. This regimen was based on our studies with carcinoid cell lines that showed synergistic cytotoxicity with sequence-specific dosing of 5-fluorouracil preceding temozolomide (TMZ). METHODS: A retrospective review was conducted of 18 patients with NETs metastatic to the liver who had failed 60 mg/month of Sandostatin LAR™ (100%), chemotherapy (61%), and hepatic chemoembolization (50%). Patients received capecitabine at 600 mg/m(2) orally twice daily on days 1-14 (maximum 1,000 mg orally twice daily) and TMZ 150-200 mg/m(2) divided into two doses daily on days 10-14 of a 28-day cycle. Imaging was performed every 2 cycles, and serum tumor markers were measured every cycle. RESULTS: Using RECIST parameters, 1 patient (5.5%) with midgut carcinoid achieved a surgically proven complete pathological response (CR), 10 patients (55.5%) achieved a partial response (PR), and 4 patients (22.2%) had stable disease (SD). Total response rate was 61%, and clinical benefit (responders and SD) was 83.2%. Of four carcinoid cases treated with CAPTEM, there was 1 CR, 1 PR, 1 SD, and 1 progressive disease. Median progression-free survival was 14.0 months (11.3-18.0 months). Median overall survival from diagnosis of liver metastases was 83 months (28-140 months). The only grade 3 toxicity was thrombocytopenia (11%). There were no grade 4 toxicities, hospitalizations, opportunistic infections, febrile neutropenias, or deaths. CONCLUSIONS: CAPTEM is highly active, well tolerated and may prolong survival in patients with well-differentiated, metastatic NET who have progressed on previous therapies.

Prophylactic pancreatectomy for intraductal papillary mucinous neoplasm does not negatively impact quality of life: a preliminary study.

BACKGROUND: Uncertainties remain over whether prophylactic surgery or surveillance is the better management option for intraductal papillary mucinous neoplasm of the pancreas. The aim of this preliminary study was to determine if differences in anxiety and quality of life exist between patients who have surgery or undergo surveillance. METHODS: Recruited patients were given the Hospital Anxiety and Depression Scale, a general survey that evaluates anxiety, and the Functional Assessment of Cancer Therapy-Pancreas, a disease-specific survey that assesses quality of life. Questionnaires were scored by standardized algorithms and compared using Student's t test or Wilcoxon rank-sum test. RESULTS: Sixteen patients had surgery and 16 patients were undergoing surveillance. Mean age was 66.8 ± 19.9 years. Responses from both groups were remarkably similar. Surgery patients scored higher on the anxiety questionnaire than surveillance patients, although not statistically significant (p = 0.09). Surgery patients scored lower on the functional well-being domain of the quality-of-life instrument (p = 0.03), though there were no differences in overall quality of life. CONCLUSION: Prophylactic surgery does not reduce quality of life, and a protocol of surveillance does not appear to generate undue anxiety in this select patient group. Further investigation with more patients is required to validate these findings.

Pancreatic cancer screening in a prospective cohort of high-risk patients: a comprehensive strategy of imaging and genetics.

PURPOSE: Pancreatic cancer is a virtually uniformly fatal disease. We aimed to determine if screening to identify curable neoplasms is effective when offered to patients at high risk. EXPERIMENTAL DESIGN: Patients at high risk of pancreatic cancer were prospectively enrolled into a screening program. Endoscopic ultrasound (EUS), magnetic resonance imaging (MRI), and genetic testing were offered by a multidisciplinary team according to each patient's risk. RESULTS: Fifty-one patients in 43 families were enrolled, with mean age of 52 years, 35% of whom were male. Of these patients, 31 underwent EUS and 33 MRI. EUS revealed two patients with pancreatic cancer (one resectable, one metastatic), five with intraductal papillary mucinous neoplasms (IPMN), seven with cysts, and six with parenchymal changes. Five had pancreatic surgery (one total pancreatectomy for pancreatic cancer, three distal and one central pancreatectomy for pancreatic intraepithelial neoplasia 2 and IPMN). A total of 24 (47%) had genetic testing (19 for BRCA1/2 mutations, 4 for CDKN2A, 1 for MLH1/MSH2) and 7 were positive for BRCA1/2 mutations. Four extrapancreatic neoplasms were found: two ovarian cancers on prophylactic total abdominal hysterectomy and bilateral salpingo-oophorectomy, one carcinoid, and one papillary thyroid carcinoma. Overall, 6 (12%) of the 51 patients had neoplastic lesions in the pancreas and 9 (18%) had neoplasms in any location. All were on the initial round of screening. All patients remain alive and without complications of screening. CONCLUSIONS: Pancreatic cancer screening for high-risk patients with a comprehensive strategy of imaging and genetics is effective and identifies curable neoplasms that can be resected. Ongoing study will better define who will benefit from screening and what screening strategy will be the most effective.

Cholangiopancreatoscopy for targeted biopsies of the bile and pancreatic ducts.

Establishing a tissue diagnosis in patients with suspected pancreaticobiliary malignancies remains challenging. Endoscopic retrograde cholangiopancreatography (ERCP)-based sampling methods have been reviewed in a previous issue of this journal but, unfortunately, the diagnostic yield continues to be inadequate in a significant minority of patients. The availability and image quality of cholangioscopy and pancreatoscopy have advanced in the last few years and our ability to make a diagnosis on imaging alone is improving. However, a definitive diagnosis requires tissue; cholangiopancreatoscopy allows targeted biopsies of the epithelium of the biliary and pancreatic ducts. This article reviews the evidence that cholangioscopy- and pancreatoscopy-guided biopsies improves diagnostic yield over ERCP-based tissue sampling techniques.

EUS-guided trucut needle biopsies in patients with solid pancreatic masses: a prospective study.

BACKGROUND: A trucut needle biopsy device that can be used to obtain specimens from the pancreas and other perigastric organs under EUS guidance has been developed and successfully tested in animals. Moreover, EUS-guided trucut needle biopsy has been used safely in humans and appears to provide more accurate results than EUS-guided FNA. This study prospectively assessed the clinical utility of this new device in patients with solid pancreatic masses. METHODS: Twenty-three consecutive patients with radiologically detected solid pancreatic masses underwent EUS-guided trucut needle biopsy. Pancreatic malignancy detected by EUS-guided trucut needle biopsy was considered a definitive diagnosis. Further diagnostic procedures and clinical course were used to establish or exclude the presence of malignancy in all other patients. RESULTS: Pancreatic tissue was obtained in 17 of the 23 patients (74%), including all patients in whom the transgastric approach was used. No acute or long-term complication was observed. Histopathologic evaluation revealed pancreatic cancer in 12 patients. CT-guided biopsy specimens were obtained in 4 of the 5 patients with a negative EUS-guided trucut needle biopsy result; two were positive for adenocarcinoma. Overall diagnostic accuracy was 61%. Subgroup analysis of the 16 patients in whom EUS-guided trucut needle biopsy was successful and who were available for follow-up revealed a diagnostic accuracy of 87.5%. CONCLUSIONS: This prospective study demonstrates that EUS-guided trucut needle biopsy, when performed transgastrically, is safe and accurate in the evaluation of patients with solid pancreatic masses.