Heads or tails: confusion about "proximal" and "distal" terminology for pancreaticobiliary anatomy.

BACKGROUND AND STUDY AIMS: The anatomical meaning of the terms "proximal" and "distal" in relation to the pancreaticobiliary anatomy can be confusing. We aimed to investigate practice patterns of use of the terms "proximal" and "distal" for pancreaticobiliary anatomy amongst various medical specialties. MATERIALS AND METHODS: An online survey link to a normal pancreaticobiliary diagram was emailed to a multispecialty physician pool. Respondents were asked to label various parts of the common bile duct (CBD) and pancreatic duct (PD) using the terms "proximal," "distal," "not sure," or "other." Variability in use of these terms between specialties was assessed. RESULTS: We received 370 completed surveys from 182 gastroenterologists (49.2 %), 97 surgeons (26.2 %), 68 radiologists (18.4 %), and 23 other physicians (6.2 %). There was overall consensus in describing the upper/sub-hepatic CBD as "proximal CBD" (73.8 %, P  = 0.1499) and the lower/pre-ampullary portion as "distal CBD" (84.6 %, P  = 0.1821). CONCLUSIONS: Although use of the terms "proximal" and "distal" is still very common to describe pancreaticobiliary anatomy, there is a discordance about its meaning, particularly for the PD. Use of descriptive terminology may be a more accurate alternative to prior ambiguous terminologies such as "proximal" or "distal" and can serve to improve communication and decrease the possibility of medical errors.

Advanced endoscopic ultrasound management techniques for preneoplastic pancreatic cystic lesions.

Pancreatic cystic lesions can be benign, premalignant or malignant. The recent increase in detection and tremendous clinical variability of pancreatic cysts has presented a significant therapeutic challenge to physicians. Mucinous cystic neoplasms are of particular interest given their known malignant potential. This review article provides a brief but comprehensive review of premalignant pancreatic cystic lesions with advanced endoscopic ultrasound (EUS) management approaches. A comprehensive literature search was performed using PubMed, Cochrane, OVID and EMBASE databases. Preneoplastic pancreatic cystic lesions include mucinous cystadenoma and intraductal papillary mucinous neoplasm. The 2012 International Sendai Guidelines guide physicians in their management of pancreatic cystic lesions. Some of the advanced EUS management techniques include ethanol ablation, chemotherapeutic (paclitaxel) ablation, radiofrequency ablation and cryotherapy. In future, EUS-guided injections of drug-eluting beads and neodymium:yttrium aluminum agent laser ablation is predicted to be an integral part of EUS-guided management techniques. In summary, International Sendai Consensus Guidelines should be used to make a decision regarding management of pancreatic cystic lesions. Advanced EUS techniques are proving extremely beneficial in management, especially in those patients who are at high surgical risk.

Endoscopic Gallbladder Drainage for Acute Cholecystitis.

BACKGROUND/AIMS: Surgery is the mainstay of treatment for cholecystitis. However, gallbladder stenting (GBS) has shown promise in debilitated or high-risk patients. Endoscopic transpapillary GBS and endoscopic ultrasound-guided GBS (EUS-GBS) have been proposed as safe and effective modalities for gallbladder drainage. METHODS: Data from patients with cholecystitis were prospectively collected from August 2004 to May 2013 from two United States academic university hospitals and analyzed retrospectively. The following treatment algorithm was adopted. Endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy and cystic duct stenting was initially attempted. If deemed feasible by the endoscopist, EUS-GBS was then pursued. RESULTS: During the study period, 139 patients underwent endoscopic gallbladder drainage. Among these, drainage was performed in 94 and 45 cases for benign and malignant indications, respectively. Successful endoscopic gallbladder drainage was defined as decompression of the gallbladder without incidence of cholecystitis, and was achieved with ERCP and cystic duct stenting in 117 of 128 cases (91%). Successful endoscopic gallbladder drainage was also achieved with EUS-guided gallbladder drainage using transmural stent placement in 11 of 11 cases (100%). Complications occurred in 11 cases (8%). CONCLUSIONS: Endoscopic gallbladder drainage techniques are safe and efficacious methods for gallbladder decompression in non-surgical patients with comorbidities.

Esophageal Stenting With Sutures: Time to Redefine Our Standards?

BACKGROUND AND STUDY AIMS: Migration is the most common complication of the fully covered metallic self-expanding esophageal stent (FCSEMS). Recent studies have demonstrated migration rates between 30% and 60%. The aim of this study was to determine the effect of fixation of the FCSEMS by endoscopic suturing on migration rate. PATIENT AND METHODS: Patients who underwent stent placement for esophageal strictures and leaks over the last year were captured and reviewed retrospectively. Group A, cases, were patients who underwent suture placement and group B, controls, were patients who had stents without sutures. Basic demographics, indications, and adverse events (AEs) were collected. Kaplan-Meier analysis and Cox regression modeling were conducted to determine estimates and predictors of stent migration in patients with and without suture placement. RESULTS: Thirty-seven patients (18 males, 48.65%), mean age 57.2 years (±16.3 y), were treated with esophageal FCSEMS. A total of 17 patients received sutures (group A) and 20 patients received stents without sutures (group B). Stent migration was noted in a total of 13 of the 37 patients (35%) [2 (11%) in group A and 11 (55%) in group B]. Using Kaplan-Meier analysis and log-rank analysis, fixation of the stent with suturing reduced the risk of migration (P=0.04). There were no AEs directly related to suture placement. CONCLUSIONS: Anchoring of the upper flare of the FCSEMS with endoscopic sutures is technically feasible and significantly reduces stent migration rate when compared with no suturing, and is a safe procedure with very low AEs rates.

Probe-based confocal laser endomicroscopy in the pancreatic duct provides direct visualization of ductal structures and aids in clinical management.

BACKGROUND: Confocal endomicroscopy provides real-time evaluation of various sites and has been used to provide detailed endomicroscopic imaging of the biliary tree. We aimed to evaluate the feasibility and utility of probe-based confocal laser endomicroscopy of the pancreatic duct as compared to cytologic and histologic results in patients with indeterminate pancreatic duct strictures. METHODS: Retrospective data on patients with indeterminate pancreatic strictures undergoing endoscopic retrograde cholangiopancreatography (ERCP) and confocal endomicroscopy were collected from two tertiary care centres. Real-time confocal endomicroscopy images were obtained during ERCP and immediate interpretation according to the Miami Classification was performed. RESULTS: 18 patients underwent confocal endomicroscopy for evaluation of pancreatic strictures from July 2011 to December 2012. Mean pancreatic duct size was 4.2mm (range 2.2-8mm). Eight cases were interpreted as benign, 4 as malignant, 4 suggestive of intraductal papillary mucinous neoplasms, and 2 appeared normal. Cytology/histopathology for 15/16 cases showed similar results to confocal endomicroscopy interpretation. Kappa coefficient of agreement between cyto/histopathology and confocal endomicroscopy was 0.8 (p=0.0001). Pancreatic confocal endomicroscopy changed management in four patients, changing the type of surgery from total pancreatectomy to whipple. CONCLUSIONS: Confocal endomicroscopy is effective in assisting with diagnosis of indeterminate pancreatic duct strictures as well as mapping of abnormal pancreatic ducts prior to surgery.

Early referral for esophageal pH monitoring is more cost-effective than prolonged empiric trials of proton-pump inhibitors for suspected gastroesophageal reflux disease.

INTRODUCTION: The most cost-effective diagnostic algorithm for gastroesophageal reflux disease (GERD) remains controversial. We hypothesized that prompt referral for esophageal pH monitoring is more cost-effective than prolonged empiric courses of proton-pump inhibitors (PPIs). DISCUSSION: A cost model was created based on a cohort of 100 patients with possible GERD who underwent pH monitoring. The additional costs incurred from pH monitoring were compared to the potential savings from avoiding unnecessary PPI usage in patients with a negative pH study. The costs of PPI therapy reach equivalence with pH monitoring after 6.4 to 23.7 weeks, depending on the PPI regimen. A total of 21,411 weeks of PPIs were prescribed beyond the recommended 8-week trial, of which 32 % were for patients who had a negative 24-h pH monitoring study. If the sensitivity of pH monitoring was 96 %, early referral for pH monitoring would have saved between $1,197 and $6,303 per patient over 10 years. This strategy remains cost-effective as long as the sensitivity of pH monitoring is above 35 %. Prompt referral for pH monitoring after a brief empiric PPI trial is a more cost-effective strategy than prolonged empiric PPI trials for patients with both esophageal and extraesophageal GERD symptoms.

Pancreatic necrosectomy using covered esophageal stents: a novel approach.

BACKGROUND: Endoscopic necrosectomy for necrotizing pancreatitis has been increasingly used as an alternative to surgical or percutaneous interventions. The use of fully covered esophageal self-expandable metallic stents may provide a safer and more efficient route for internal drainage. The aim of this study was to evaluate the safety and efficacy of endoscopic treatment of pancreatic necrosis with these stents. METHODS: A retrospective study at 2 US academic hospitals included patients with infected pancreatic necrosis from July 2009 to November 2012. These patients underwent transgastric placement of fully covered esophageal metallic stents draining the necrosis. After necrosectomy, patients underwent regular sessions of endoscopic irrigation and debridement of cystic contents. The efficacy endpoint was successful resolution of infected pancreatic necrosis without the need for surgical or percutaneous interventions. RESULTS: Seventeen patients were included with the mean age of 41±12 years. A mean of 5.3±3.4 sessions were required for complete drainage and the follow-up period was 237.6±165 days. Etiology included gallstone pancreatitis (6), alcohol abuse (6), s/p distal pancreatectomy (2), postendoscopic retrograde cholangiopancreatography pancreatitis (1), medication-induced pancreatitis (1), and hyperlipidemia (1). Mean size of the necrosis was 14.8 cm (SD 5.6 cm), ranging from 8 to 19 cm. Two patients failed endoscopic intervention and required surgery. The only complication was a perforation during tract dilation, which was managed conservatively. Fifteen patients (88%) achieved complete resolution. CONCLUSIONS: Endoscopic necrosectomy with covered esophageal metal stents is a safe and successful treatment option for infected pancreatic necrosis.

Pre- and post-training session evaluation for interobserver agreement and diagnostic accuracy of probe-based confocal laser endomicroscopy for biliary strictures.

BACKGROUND AND AIM: Current diagnostic modalities for indeterminate biliary strictures offer low accuracy. Probe-based confocal laser endomicroscopy (pCLE) permits microscopic assessment of mucosal structures by obtaining real-time high-resolution images of the mucosal layers of the gastrointestinal tract. Previously, an interobserver study demonstrated poor to fair agreement even among experienced confocal endomicroscopy operators. Our objective was to assess interobserver agreement and diagnostic accuracy upon completion of a pCLE training session. METHODS: Forty de-identified pCLE video clips of indeterminate biliary strictures were sent to five endoscopists at four tertiary care centers for scoring. Observers subsequently attended a teaching session by an expert pCLE user that included 20 training clips and rescored the same pCLE video clips, which were randomized and renumbered. RESULTS: Pre-training interobserver agreement for all observers was 'fair' (Κ: 0.31, P-value: <0.0001) and diagnostic accuracy was 72% (55-80%). Post-training interobserver agreement for all observers was 'substantial' (Κ: 0.74, P-value: <0.0001) and diagnostic accuracy was 89% (80-95%). Using a paired t-test, we observed an increase of 17% (95% CI 7.6-26.4) in post-training diagnostic accuracy (t = 5.01, df = 4, P-value 0.007). CONCLUSIONS: Interobserver agreement and diagnostic accuracy improved after observers underwent training by an expert pCLE user with a specific sequence set. Users should participate in such training programs to maximize diagnostic accuracy of pCLE evaluation.

Location of bile leak predicts the success of ERCP performed for postoperative bile leaks.

BACKGROUND: ERCP is effective for treating a bile leak (BL) after cholecystectomy (CCY), but few data exist on its effectiveness after hepatobiliary surgery (HBS). OBJECTIVE: To determine the effectiveness of ERCP for treating BLs after HBS compared with BLs after cholecystectomy and to identify factors associated with treatment success. DESIGN: Retrospective cohort. SETTING: Academic tertiary-care referral center. PATIENTS: Patients referred from 2001 to 2009 for ERCP treatment of BL after cholecystectomy or HBS. INTERVENTIONS: ERCP. MAIN OUTCOME MEASUREMENTS: Resolution of BL after a single ERCP. RESULTS: A total of 223 patients were identified and 46 were excluded. Fifty underwent ERCP for treatment of BL after HBS and 127 after CCY. A single ERCP was successful at resolving BL in 89% of patients. Failure occurred in 7 HBS patients (14%) and 12 CCY patients (9%) (P = .379). After multiple ERCPs, success improved to 95% of the CCY group and 86% of the HBS group (P = .033). HBS patients underwent 30% more ERCPs (P = .049). ERCP was 3.3 times more likely to be successful in patients with cystic duct or duct of Luschka BLs (P = .028). Patients undergoing biliary stent placement were significantly more likely to have successful outcomes (odds ratio 71.0, P < .001). Surgical history or biliary sphincterotomy did not affect outcome. Odds of treatment failure were 3.5 times higher for each additional ERCP performed (P < .001). LIMITATIONS: Single-center, retrospective study. CONCLUSIONS: ERCP is effective for treating postoperative BLs. Location of a BL and placement of a biliary stent are the best predictors of endoscopic treatment success.

Cyst fluid carcinoembryonic antigen is an accurate diagnostic marker of pancreatic mucinous cysts.

OBJECTIVES: Endoscopic ultrasound (EUS) may offer a diagnostic tool through the combination of imaging and guided fine-needle aspiration of pancreatic cysts. The purpose of this investigation was to determine the most accurate test for differentiating mucinous from nonmucinous cysts. METHODS: The results of EUS imaging, cytology, and cyst fluid biochemical markers were prospectively collected and compared in a large single-center study (776 patients) using histology or malignant cytology as the final diagnostic standard in 198 patients. RESULTS: The mean cyst fluid carcinoembryonic antigen (CEA) was greater in mucinous cysts (4703.0 ng/mL) compared with nonmucinous cysts (25.8 ng/mL) (P = 0.008). When using the optimal cutoff value of 109.9 ng/mL, the CEA was more accurate (86%, receiver operating characteristic area = 0.928) than EUS imaging (48%) and cytology (58%) in predicting a mucinous cyst (P < 0.0001). Malignant cysts had a mean cyst fluid CEA value (2558.2 ng/mL) similar to benign cysts (4700.2 ng/mL). Cytology (75%) more accurately diagnosed malignant cysts than EUS (66%) and CEA (62%) (P < 0.05). CONCLUSIONS: Cyst fluid CEA concentration provides a highly accurate test for the diagnosis of a mucinous cyst, but does not distinguish benign from malignant cysts. Cytology is the most accurate test for the diagnosis of a malignant cyst.

Prognosis of invasive intraductal papillary mucinous neoplasm depends on histological and precursor epithelial subtypes.

OBJECTIVE: Invasive cancers arising from intraductal papillary mucinous neoplasm (IPMN) are recognised as a morphologically and biologically heterogeneous group of neoplasms. Less is known about the epithelial subtypes of the precursor IPMN from which these lesions arise. The authors investigate the clinicopathological characteristics and the impact on survival of both the invasive component and its background IPMN. DESIGN AND PATIENTS: The study cohort comprised 61 patients with invasive IPMN (study group) and 570 patients with pancreatic ductal adenocarcinoma (PDAC, control group) resected at a single institution. Multivariate analyses were performed using a stage-matched Cox proportional hazard model. RESULTS: The histology of invasive components of the IPMN cohort was tubular in 38 (62%), colloid in 16 (26%), and oncocytic in seven (12%). Compared with PDAC, invasive IPMNs were associated with a lower incidence of adverse pathological features and improved mortality by multivariate analysis (HR 0.58; 95% CI 0.39 to 0.86). In subtype analysis, this favourable outcome remained only for colloid and oncocytic carcinomas, while tubular adenocarcinoma was associated with worse overall survival, not significantly different from that of PDAC (HR 0.85; 95% CI 0.53 to 1.36). Colloid and oncocytic carcinomas arose only from intestinal- and oncocytic-type IPMNs, respectively, and were mostly of the main-duct type, whereas tubular adenocarcinomas primarily originated in the gastric background, which was often associated with branch-duct IPMN. Overall survival of patients with invasive adenocarcinomas arising from gastric-type IPMN was significantly worse than that of patients with non-gastric-type IPMN (p=0.016). CONCLUSIONS: Tubular, colloid and oncocytic invasive IPMNs have varying prognosis, and arise from different epithelial subtypes. Colloid and oncocytic types have markedly improved biology, whereas the tubular type has a course that resembles PDAC. Analysis of these subtypes indicates that the background epithelium plays an equally, if not more, important role in defining the biology and prognosis of invasive IPMNs.

A prospective, randomized trial of esophageal submucosal tunnel closure with a stent versus no closure to secure a transesophageal natural orifice transluminal endoscopic surgery access site.

BACKGROUND: Secure esophagotomy closure methods are a critical element in the advancement of transesophageal natural orifice transluminal endoscopic surgery (NOTES) procedures. OBJECTIVE: To compare the clinical outcomes in swine receiving an esophageal stent or no stent after a submucosal tunnel NOTES access procedure. DESIGN: Prospective, randomized, controlled trial in 10 Yorkshire swine. SETTING: Academic center. INTERVENTION: An endoscopic mucosectomy device was used to create an esophageal mucosal defect. An endoscope was advanced through a submucosal tunnel into the mediastinum and thorax, and diagnostic mediastinoscopy and thoracoscopy were performed. Ten animals were randomized to no stenting (n = 5) or stenting (n = 5) with a prototype small-intestine submucosa-covered stent. MAIN OUTCOME MEASUREMENTS: Gross and histologic appearance of the mucosectomy and esophagotomy sites as well as clinical outcomes. RESULTS: There was a significant difference in the overall procedure time between the animals that received a stent (35.0 min, range 27-46.0 min) and those with no closure (19.0 min, range 17-32 min) (P value = .018). The unstented group achieved endoscopic and histologic evidence of complete re-epithelialization and healing (100%) at the mucosectomy site compared with the stented group (20%, P = .048). Stent migration into the stomach occurred in two swine. Both groups had complete closure of the submucosal tunnel and well-healed esophagotomy sites. LIMITATIONS: Animal study, small number of subjects. CONCLUSION: The placement of a covered esophageal stent significantly interferes with mucosectomy site healing.

Feasibility of EUS-guided injection of irinotecan-loaded microspheres into the swine pancreas.

BACKGROUND: LC beads (Biocompatibles International plc) are designed for the time-released delivery of the chemotherapeutic agent irinotecan into focal, hypervascularized, hepatic tumors. OBJECTIVE: To determine the feasibility of EUS-guided injection of LC beads (with/without irinotecan) into the swine pancreas. DESIGN: Survival animal study. SETTING: Academic center. SUBJECTS: This study involved 12 Yorkshire swine. INTERVENTION: LC beads without irinotecan and loaded with up to 300 mg of irinotecan were injected under EUS guidance with a 19-gauge needle into the tail of the pancreas. CT scanning and necropsy with histology were performed at day 7. MAIN OUTCOME MEASUREMENTS: Feasibility of the injections, gross and microscopic evidence of pancreatic inflammation, and clinical tolerance by the animals. RESULTS: After injection of LC beads with/without irinotecan, in 10 of 12 animals an intrapancreatic, hyperechoic focus with an average diameter of 2.2 cm was visible by EUS, and a hypodense area in the tail of the pancreas was visible by contrast CT. In 2 animals (1 with irinotecan and 1 without) no beads were seen on CT. In 10 of 12 animals, a depot of beads was located in the tail of the pancreas on gross inspection and histology. Drug depot with only localized pancreatic tissue reactions was seen on histopathologic review. LIMITATIONS: Animal study. CONCLUSION: The EUS-guided injection of LC beads (with/without irinotecan) into the pancreas of the pig is feasible and safe. This technique is a potential minimally invasive local treatment option for locally advanced pancreatic cancer.

Stent placement provides safe esophageal closure in thoracic NOTES(TM) procedures.

BACKGROUND: Safe esophageal closure remains a challenge in transesophageal Natural Orifice Transluminal Endoscopic Surgery (NOTES). Previously described methods, such as suturing devices, clips, or submucosal tunneling, all have weaknesses. In this survival animal series, we demonstrate safe esophageal closure with a prototype retrievable, antimigration stent. METHODS: Nine Yorkshire swine underwent thoracic NOTES procedures. A double-channel gastroscope equipped with a mucosectomy device was used to create an esophageal mucosal defect. A 5-cm submucosal tunnel was created and the muscular esophageal wall was incised with a needle-knife. Mediastinoscopy and thoracoscopy were performed in all swine; lymphadenectomy was performed in seven swine. A prototype small intestinal submucosal (SurgiSIS(®)) covered stent was deployed over the mucosectomy site and tunnel. Three versions of the prototype stent were developed. Prenecropsy endoscopy confirmed stent location and permitted stent retrieval. Explanted esophagi were sent to pathology. RESULTS: Esophageal stenting was successful in all animals. Stent placement took 15.8 ± 4.8 minuted and no stent migration occurred. Prenecropsy endoscopy revealed proximal ingrowth of esophageal mucosa and erosion with Stent A. Mucosal inflammation and erosion was observed proximally with Stent B. No esophageal erosion or pressure damage from proximal radial forces was seen with Stent C. On necropsy, swine 5 had a 0.5-cm periesophageal abscess. Histology revealed a localized inflammatory lesion at the esophageal exit site in swine 1, 3, and 9. The mucosectomy site was partially healed in three swine and poorly healed in six. All swine thrived clinically, except for a brief period of mild lethargy in swine 9 who improved with short-term antibiotic therapy. The submucosal tunnels were completely healed and no esophageal bleeding or stricture formation was observed. All swine survived 13.8 ± 0.4 days and gained weight in the postoperative period. CONCLUSIONS: Esophageal stenting provides safe closure for NOTES thoracic procedures but may impede healing of the mucosectomy site.

Natural orifice transesophageal thoracoscopic surgery: A review of the current state.

Since the concept of Natural Orifice Translumenal Endoscopic Surgery (NOTES) was introduced, it has continued to gain significantly in popularity and enthusiasm for its potential clinical applications. The ability to perform conventional laparoscopic and thoracoscopic procedures without the creation of scars and perhaps faster and less painful recovery has prompted a worldwide devotion to further this field. While intra-abdominal NOTES has rapidly transitioned from animal models to human trials, applying the NOTES concept to perform thoracic procedures has been slower to gain momentum. The goal of this review is to summarize the current state of transesophageal NOTES thoracoscopy by looking at its potential for diagnostic and therapeutic interventions as well as the challenges in transitioning to human trials.

Diagnostic and therapeutic endoscopic approaches to intraductal papillary mucinous neoplasm.

Pancreatic cystic lesions are increasingly identified on routine imaging. One specific lesion, known as intraductal papillary mucinous neoplasm (IPMN), is a mucinous, pancreatic lesion characterized by papillary cells projecting from the pancreatic ductal epithelium. The finding of mucin extruding from the ampulla is essentially pathognomonic for diagnosing these lesions. IPMNs are of particular interest due to their malignant potential. Lesions range from benign, adenomatous growths to high-grade dysplasia and invasive cancer. These mucinous lesions therefore require immediate attention to determine the probability of malignancy and whether observation or resection is the best management choice. Unresected lesions need long-term surveillance monitoring for malignant transformation. The accurate diagnosis of these lesions is particularly challenging due to the substantial similarities in morphology of pancreatic cystic lesions and limitations in current imaging technologies. Endoscopic evaluation of these lesions provides additional imaging, molecular, and histologic data to aid in the identification of IPMN and to determine treatment course. The aim of this article is to focus on the diagnostic and therapeutic endoscopic approaches to IPMN.

High-grade atypical epithelial cells in pancreatic mucinous cysts are a more accurate predictor of malignancy than "positive" cytology.

BACKGROUND: The Sendai guidelines for risk assessment of malignancy in patients with mucinous cysts lists "positive" cytology as a high-risk feature. In the current study, the authors hypothesized that a cytological threshold of high-grade atypical epithelial cells (AEC) is a more accurate predictor of malignancy. METHODS: The clinical, radiological, and cytological data of 112 patients with histologically confirmed mucinous cysts of the pancreas were reviewed. Cytology slides were blindly reviewed and cells were classified as benign, AEC, or malignant. On histology, neoplasms were grouped as benign (low-grade and moderate dysplasia) and malignant (high-grade dysplasia/carcinoma in situ and invasive carcinoma). RESULTS: There were 92 patients with an intraductal papillary mucinous neoplasm (IPMN) and 20 with a mucinous cystic neoplasm; 39 were malignant and 73 were benign (42 with low-grade dysplasia and 31 with moderate dysplasia). Only 28% (11 of 39) of the malignant cysts were cytologically malignant with a sensitivity of 29%, a specificity of 100%, and an accuracy of 75%. AEC detected 17 additional cancers (44% of all malignant cysts; 16% more than detected on the basis of "positive" cytology). By using AEC as a surgical triage threshold, the sensitivity was 72%, the specificity was 85%, and the accuracy was 80%, with similar values for small (≤ 3 cm) branch duct IPMN. Nine of 73 (12%) benign cysts were identified with AEC, 4 of which had moderate dysplasia. AEC had a positive predictive value of 87% for the detection of a mucinous cyst with moderate dysplasia or worse. CONCLUSIONS: AEC are a more accurate predictor of malignancy than "positive" cytology in aspirates of pancreatic mucinous cysts, including small branch duct IPMN. AEC warrant a "suspicious" interpretation for appropriate surgical triage.

Endoscopic transesophageal mediastinal lymph node dissection and en bloc resection by using mediastinal and thoracic approaches (with video).

BACKGROUND: The criterion standard for sampling mediastinal lymph nodes is cervical mediastinoscopy. Current methods that require transthoracic or cervical incisions can result in significant postoperative pain. OBJECTIVE: To determine the feasibility of a novel, transesophageal endoscopic technique for mediastinal lymph node dissection and en bloc resection. DESIGN: Nonsurvival and survival animal study. SETTING: Animal trial at a tertiary-care academic center. SUBJECTS: This study involved 12 Yorkshire swine. INTERVENTION: An endoscopic cap band mucosectomy device was used to create an esophageal mucosal defect. By using the tip of the endoscope and biopsy forceps, a submucosal tunnel was fashioned, and, within the submucosal space, a hook-knife incised the muscular esophageal wall. The endoscope was then advanced into the mediastinum and chest. Mediastinoscopy and thoracoscopy were performed to identify lymph node stations. Prototype endoscopic devices permitted lymph node dissection prior to removal with an electrocautery snare. A covered prototype stent was placed over the mucosectomy site. MAIN OUTCOME MEASUREMENTS: Feasibility of endoscopic transesophageal lymphadenectomy. RESULTS: Three lymph nodes (1 para-aortic and 2 right paratracheal) were removed in the 3 nonsurvival swine. Nine swine were survived for 14 days (range 13-14 days) and had a total of 7 lymph nodes (2 para-aortic and 5 paratracheal) removed. Two swine had no endoscopically visible lymph nodes in the mediastinum or chest. Lymph node dissection and resection was successful in all cases where lymph nodes were identified. Lymphadenectomy was completed in a median time of 20.0 minutes (range 8-60 minutes); median total procedure time was 70.0 minutes (range 28-105 minutes). Median lymph node size was 1.1 cm (range 0.6-1.4 cm). LIMITATIONS: Animal study. CONCLUSION: An endoscopic transesophageal approach can accomplish mediastinal lymph node dissection and en bloc resection and provides architecturally intact lymph node specimens for histologic examination.

Pancreatic cystic lesions: when to watch, when to operate, and when to ignore.

Pancreatic cystic lesions are being increasingly identified with the widespread use of state-of-the-art imaging. These lesions are categorized into a broad range of neoplastic cysts and inflammatory pseudocysts. Identification of a pancreatic cyst requires the clinician to focus on the main clinical challenge of the benign or malignant nature of the cyst. Neoplastic cysts range the spectrum from benign, to premalignant, to frank malignancy. The management of these lesions is difficult, and the decision to resect or observe a lesion is hampered by limitations in current imaging and tissue sampling techniques that prevent the accurate characterization of all lesions. This article reviews current guidelines for the evaluation of pancreatic cystic lesions, underscores the challenges posed by these lesions, and discusses current and future studies that will aid in patient management.