Clinical profiles and outcomes in idiopathic duct-centric chronic pancreatitis (type 2 autoimmune pancreatitis): the Mayo Clinic experience.

OBJECTIVE: Idiopathic duct-centric chronic pancreatitis (IDCP), also known as type 2 autoimmune pancreatitis (AIP), is an uncommon subtype of AIP. International Consensus Diagnostic Criteria for IDCP propose that the diagnosis requires pancreatic histology and/or concurrent IBD. We examined our experience with IDCP (type 2 AIP) to assess the appropriateness of these criteria, and identify unique characteristics in patients presenting with acute pancreatitis. DESIGN: We reviewed the Mayo Clinic AIP database through May 2014 to identify subjects with either definitive (n=31) or probable (n=12) IDCP. We compared demographic and clinical factors based on strength of diagnostic confidence (definitive versus probable), presence of IBD, and acute pancreatitis as the presenting manifestation. Relapse-free survival was determined using the Kaplan-Meier method. RESULTS: The clinical profiles were similar irrespective of the diagnostic criteria fulfilled. Common clinical presentations included acute pancreatitis (n=25, 58.1%, 12 of whom (27.9%) had recurrent pancreatitis) and pancreatic mass/obstructive jaundice (n=15, 34.9%). The cumulative relapse rate was 10.6% at 3 years (median follow-up 2.9 years). Relapse-free survival was similar for the different diagnostic categories, but was decreased in those initially presenting with acute pancreatitis (p=0.047) or treated with steroids (vs surgery, p=0.049). CONCLUSIONS: The current diagnostic classification of probable IDCP and the inclusion of IBD as a supportive criterion appear valid, because patients have similar clinical profiles and disease-related outcomes to those with definitive IDCP. Concurrent IBD, especially in young patients, may suggest when IDCP is the underlying cause of recurrent acute pancreatitis, but additional studies are needed for validation.

Obstructive jaundice in autoimmune pancreatitis can be safely treated with corticosteroids alone without biliary stenting.

OBJECTIVE: Autoimmune pancreatitis (AIP) responds dramatically to corticosteroids treatment. We reviewed our experience to determine the safety and effectiveness of treating obstructive jaundice in definitive AIP with corticosteroids alone without biliary stenting. METHODS: From our AIP database, we retrospectively identified type 1 AIP subjects whose jaundice was treated with corticosteroids alone without biliary stenting. Their medical records were reviewed and clinical data were evaluated to determine the outcomes. RESULTS: Fifteen AIP subjects (87% male, mean age 68.4 years) were treated with corticosteroids at initial presentation (n = 8), first (n = 5) or subsequent (n = 2) relapse. Mean values (upper limit of normal, ULN) of liver tests prior to corticosteroids were aspartate aminotransferase (AST) 203.5u/l (4 × ULN), alanine aminotransferase (ALT) 325.8u/l (6 × ULN), alkaline phosphatase (ALP) 567.4u/l (5 × ULN), and total bilirubin (TB) 5.9 mg/dl (5.9 × ULN). At first follow-up (mean 4 days) the decrease was 54.9% for AST, 51.6% for ALT, 33% for ALP and 47.2% for TB (all p < 0.05). After 15-45 days, all patients had normal AST, 3/15 had ALT > 1.5 × ULN, 1/15 had ALP > 1.5 × ULN, 1/15 had TB > 1.5 × ULN. No patient required biliary stent placement, or developed cholangitis or other infectious complications during steroid treatment. CONCLUSION: Under the supervision of an experienced pancreatologist and with close monitoring of patients, obstructive jaundice secondary to definitive AIP can be safely and effectively managed with corticosteroids alone, without the need for biliary stenting.

EUS-guided ethanol lavage does not reliably ablate pancreatic cystic neoplasms (with video).

BACKGROUND: The true efficacy of EUS-guided ethanol lavage (EEL) of pancreatic cystic neoplasms is unclear. This study aimed to assess long-term outcomes and adverse events of EEL by using a standardized protocol. METHODS: Single-center, prospective, pilot study in which participants with suspected mucinous cyst neoplasms or branch duct intraductal papillary mucinous neoplasms ≥1 cm in maximum diameter underwent EEL with 80% ethanol. Follow-up cross-sectional imaging was obtained to assess for changes in cyst volume. RESULTS: Twenty-three patients underwent EEL (57% male, mean age 70 years). Mean duration of follow-up was 40 months (range 9-82 months). Mean calculated final concentration of ethanol achieved in treated cysts was 50% (range 0%-79%). Complete resolution of pancreatic cystic neoplasms occurred in 2 participants (9%). When stratified into those participants who achieved ≥80% versus <80% reduction in cyst volume, no statistically significant differences were seen with regard to patient demographics, cyst characteristics, or final concentration of ethanol achieved in the treated cyst. Greater decreases in cyst volume were seen in presumed nonmucinous cysts compared with presumed mucinous cysts (P = .006). Two early adverse events occurred. Five participants died during the study follow-up period (4 from nonpancreatic causes), including 1 participant who was diagnosed with pancreatic adenocarcinoma thought to have arisen from the treated branch duct intraductal papillary mucinous neoplasm 41 months after undergoing EEL. CONCLUSIONS: As performed in this study, EEL therapy does not appear to be a promising method for prevention of malignancy in pancreatic cysts. Endoscopic methods that effectively and completely ablate pancreatic cystic neoplasms are needed. ( CLINICAL TRIAL REGISTRATION NUMBER: NCT02158039.).

Detection of peritoneal carcinomatosis by EUS fine-needle aspiration: impact on staging and resectability (with videos).

BACKGROUND: Peritoneal carcinomatosis (PC) greatly affects cancer staging and resectability. OBJECTIVE: To compare the PC detection rate by using EUS and noninvasive imaging and to determine the impact on staging and resectability. DESIGN: Retrospective study. SETTING: Single tertiary-care referral center. PATIENTS: A prospectively maintained EUS database was reviewed to identify patients who underwent EUS-guided FNA (EUS-FNA) of a peritoneal anomaly. Findings were compared with a strict criterion standard that incorporated cytohistologic, radiologic, and clinical data. INTERVENTION: EUS-FNA of a peritoneal anomaly. MAIN OUTCOME MEASUREMENTS: Safety and diagnostic yield. RESULTS: Of 106 patients, a criterion standard was available in 98 (39 female patients; median age, 65 years). The sensitivity, specificity, and accuracy of EUS-FNA versus CT/magnetic resonance imaging (MRI) was 91% versus 28%, 100% versus 85%, and 94% versus 47%, respectively. In newly diagnosed cancer patients, peritoneal FNA upstaged 17 patients (23.6%). Of 32 patients deemed resectable by pre-EUS CT/MRI, 15 (46.9%) were deemed unresectable based solely on peritoneal FNA. The odds of FNA changing the resectability status remained highly significant after adjustment for cancer type, time between CT/MRI and EUS-FNA, and the quality of CT/MRI. The malignant appearance of the peritoneal anomaly but not the presence of ascites on EUS predicted a positive FNA finding (odds ratio 2.56; 95% confidence interval, 1.23-5.4 and odds ratio 0.83; 95% confidence interval, 0.4-1.8, respectively). There were 3 adverse events among 4 patients. Two of the patients developed abdominal pain and one each hypertensive urgency and pancreatitis. LIMITATIONS: Retrospective design, single-center, bias toward EUS as a diagnostic test. CONCLUSION: Peritoneal EUS-FNA appears to safely detect radiographically occult PC and improve cancer staging and patient care.

Impact of celiac neurolysis on survival in patients with pancreatic cancer.

BACKGROUND: Pancreatic cancer (PC) often produces pain that is difficult to control. Celiac neurolysis (CN) is performed with the goal of improving pain control and quality of life while reducing opioid-related side effects. OBJECTIVE: We aimed to evaluate whether CN provides a survival advantage for PC patients. DESIGN: Retrospective case-control study. SETTING: Single tertiary-care referral center. PATIENTS: Review of a prospectively maintained database identified patients with unresectable PC who underwent CN over a 12-year period. Each patient was matched to 2 control patients with unresectable PC. INTERVENTION: CN, which included both celiac plexus neurolysis (CPN) and celiac ganglia neurolysis (CGN). MAIN OUTCOME MEASUREMENTS: Median survival in Kaplan-Meier curves and hazard ratios. RESULTS: A total of 417 patients underwent CN and were compared with 840 controls with PC. Baseline characteristics were similar except the CN group had greater weight loss and pain requiring opioids. A mean of 16.6 ± 5.8 mL of alcohol was administered. For patients who underwent CN, the median survival from the time of presentation was shorter compared with controls (193 vs 246 days; hazard ratio 1.32; 95% confidence interval, 1.13-1.54). There was no difference in survival with unilateral or bilateral injection. However, EUS-guided CN was associated with longer survival compared with non-EUS approaches, and those who received CPN had longer survival compared with CGN. LIMITATIONS: Single center, retrospective. CONCLUSION: Our study suggests that CN is an independent predictor of shortened survival in PC patients. A prospective study is needed to verify the findings and determine whether shortened survival results from CN or from other features such as performance status and tumor-related characteristics. It is also imperative to verify our finding that EUS-guided CN provides a survival advantage over other approaches and whether CPN prolongs survival compared with CGN.

EUS-derived criteria for distinguishing benign from malignant metastatic solid hepatic masses.

BACKGROUND: Detection of hepatic metastases during EUS is an important component of tumor staging. OBJECTIVE: To describe our experience with EUS-guided FNA (EUS-FNA) of solid hepatic masses and derive and validate criteria to help distinguish between benign and malignant hepatic masses. DESIGN: Retrospective study, survey. SETTING: Single, tertiary-care referral center. PATIENTS: Medical records were reviewed for all patients undergoing EUS-FNA of solid hepatic masses over a 12-year period. INTERVENTIONS: EUS-FNA of solid hepatic masses. MAIN OUTCOME MEASUREMENTS: Masses were deemed benign or malignant according to predetermined criteria. EUS images from 200 patients were used to create derivation and validation cohorts of 100 cases each, matched by cytopathologic diagnosis. Ten expert endosonographers blindly rated 15 initial endosonographic features of each of the 100 images in the derivation cohort. These data were used to derive an EUS scoring system that was then validated by using the validation cohort by the expert endosonographer with the highest diagnostic accuracy. RESULTS: A total of 332 patients underwent EUS-FNA of a hepatic mass. Interobserver agreement regarding the initial endosonographic features among the expert endosonographers was fair to moderate, with a mean diagnostic accuracy of 73% (standard deviation 5.6). A scoring system incorporating 7 EUS features was developed to distinguish benign from malignant hepatic masses by using the derivation cohort with an area under the receiver operating curve (AUC) of 0.92; when applied to the validation cohort, performance was similar (AUC 0.86). The combined positive predictive value of both cohorts was 88%. LIMITATIONS: Single center, retrospective, only one expert endosonographer deriving and validating the EUS criteria. CONCLUSION: An EUS scoring system was developed that helps distinguish benign from malignant hepatic masses. Further study is required to determine the impact of these EUS criteria among endosonographers of all experience.

The string sign for diagnosis of mucinous pancreatic cysts.

BACKGROUND AND STUDY AIMS: Pancreas cyst fluid analysis does not provide optimal discrimination between mucinous and nonmucinous cysts. The aim of this study was to assess the performance characteristics of the "string sign" - a test performed at the time of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), for the diagnosis of mucinous pancreatic cysts (branch duct intraductal papillary mucinous neoplasms [bIPMN] and mucinous cystic neoplasms). PATIENTS AND METHODS: Patients undergoing EUS-FNA of pancreatic cystic lesions at one referral center between 2003 and 2012 were included. The string sign was performed prospectively, and was considered positive if ≥ 1 cm string formed in cyst fluid and lasted for ≥ 1 second. Performance characteristics of the string sign and a sequential cyst fluid test interpretation model were assessed. RESULTS: For 98 histologically proven cases, the sensitivity, specificity, positive predictive value, and negative predictive value of the string sign for diagnosis of mucinous cysts were 58 % (95 % confidence interval [CI] 44 % - 70 %), 95 % (83 % - 99 %), 94 % (81 % - 99 %), and 60 % (46 % - 72 %), respectively. When string sign results and carcinoembryonic antigen (CEA) concentration (≥ 200 ng/mL) were combined, diagnostic accuracy improved from 74 % and 83 %, respectively, to 89 % (P ≤ 0.03). Among bIPMN, a positive string sign was associated with gastric and intestinal epithelial subtypes. The sequential cyst fluid test interpretation model (including cytology, mucin stain, CEA, and string sign) yielded an overall sensitivity for mucinous lesions of 96 %, with a specificity of 90 %. CONCLUSIONS: The string sign is highly specific for diagnosis of mucinous pancreatic cysts, and improves overall diagnostic accuracy of pancreatic cyst fluid analysis. Sequential cyst fluid test interpretation yields high diagnostic sensitivity and specificity for mucinous cysts.

Prospective evaluation of adverse events following lower gastrointestinal tract EUS FNA.

OBJECTIVES: There are virtually no data concerning the risk of adverse events (AEs) following lower gastrointestinal (LGI) endoscopic ultrasound (EUS). Our aim was to determine the incidence and factors associated with AEs following LGI EUS fine needle aspiration (FNA). METHODS: We conducted a prospective cohort study at a tertiary referral center. Five hundred and sixty-three patients underwent LGI EUS FNA between 1 January 2004 and 1 January 2012. We analyzed the 502 patients who had complete follow-up. AE severity was graded (1-5) utilizing Common Terminology Criteria or Visual Analog Scale. AEs were assessed during the procedures, in clinical follow-up, during phone interviews conducted at 7-14 days, and final clinical and/or phone interviews at 2-4 months. RESULTS: AEs developed in 103 (20.5%) patients and were classified as grade 1, 2, 3, or 4 in 34 (6.8%), 41 (8.2%), 23 (4.6%), and 5 (1.0%) patients, respectively. Bleeding and pain were the commonest AEs. No deaths occurred. On multivariate analysis, AEs were associated with prior pain (odds ratio (OR): 3.83, 95% confidence interval (CI): 2.35-6.25), FNA from a site other than a lymph node (LN) or gut wall (OR: 2.26, 95% CI: 1.10-4.70), and malignant FNA cytology (OR: 1.80, 95% CI: 1.10-2.97); serious (grade 3-4) AEs were associated with prior pain (OR: 15.21, 95% CI: 5.04-45.85) and FNA from a site other than a LN or gut wall (OR: 3.25, 95% CI: 1.15-9.20). CONCLUSIONS: LGI EUS FNA is associated with a high rate of serious grades 3-4 AEs. This may reflect the total number of associated interventions and the frequency of underlying pathology and symptoms.

Treatment of relapsing autoimmune pancreatitis with immunomodulators and rituximab: the Mayo Clinic experience.

BACKGROUND: There is a paucity of data on long-term management of type 1 autoimmune pancreatitis (AIP), a relapsing steroid-responsive disorder. OBJECTIVE: We describe our experience with treatment of relapses and maintenance of remission using steroid-sparing immunomodulators (IMs) and induction of remission using rituximab (RTX). METHODS: We obtained details of disease relapse and treatment in 116 type 1 AIP patients from clinic visits, medical records and telephone interviews. We compared relapse free survival in those treated with IMs versus those treated with steroids alone, assessed patients' response to RTX, and identified treatment-related complications. RESULTS: During a median follow-up of 47 months, 52/116 AIP patients experienced 76 relapse episodes. The first relapse was treated with another course of steroids in 24 patients, and with steroids plus IM in another 27 patients; subsequent relapse-free survival until a second relapse was similar in the two groups (p=0.23). 38 patients received an IM for >2 months; failure or intolerance of IM therapy occurred in 17 (45%). 12 patients with steroid or IM intolerance/resistance were treated with RTX, an antiCD20 antibody; 10 (83%) experienced complete remission and had no relapses while on maintenance therapy. Treatment-limiting side effects related to RTX were uncommon. CONCLUSIONS: In type 1 AIP relapses are common. Relapse-free survival is similar in those treated with steroids plus IM compared to those treated with steroids alone. Nearly half the patients on IMs will relapse during treatment. RTX is effective in the treatment of both IM resistant and steroid intolerant patients.

Gastric antral injections of botulinum toxin delay gastric emptying but do not reduce body weight.

BACKGROUND & AIMS: Gastric injections of botulinum toxin A (BTA) have been reported to delay gastric emptying, increase satiation, and reduce body weight, but there are few data from randomized, placebo-controlled studies. METHODS: We enrolled 60 obese participants in a 24-week, double-blind, randomized, placebo-controlled, concealed allocation trial to compare the effects of gastric antral injections of BTA (100, 300, or 500 U) and saline placebo. The study was conducted at an outpatient clinical research unit. Participants were given one set of injections of BTA or placebo into the gastric antral muscularis propria by using endoscopic ultrasound guidance. Gastric emptying of solids was measured by scintigraphy; we also measured body weight, satiation (maximum tolerated volume in a caloric liquid drink test), calorie intake (by food frequency questionnaire), gastrointestinal symptoms, and psychological aspects of eating behavior (by rating scale). RESULTS: Compared with baseline values, 2 weeks after injections, the mean half-time for gastric emptying of solids increased by 0.8, 14, 24, and 14 minutes among subjects given placebo, 100, 300, or 500 U BTA, respectively (P = .24 overall, P = .04 for the group given 300 U vs placebo); 16 weeks after the injections, mean body weights were reduced by 2.2, 0.2, 2.3, and 3.0 kg in these groups, respectively. There were no statistically significant differences in mean body weight change, satiation volume, caloric intake, gastrointestinal symptoms, or psychological aspects of eating behavior among groups. CONCLUSIONS: Gastric antral injections of BTA may delay gastric emptying at a dose of 300 U but do not cause early satiety, altered eating behaviors, or loss of body weight. Clinicaltrials.gov identifier: NCT00976443.

Comparison of methods to detect neoplasia in patients undergoing endoscopic ultrasound-guided fine-needle aspiration.

BACKGROUND & AIMS: Digital image analysis (DIA) and fluorescence in situ hybridization (FISH) can be used to evaluate biliary strictures with greater accuracy than conventional cytology (CC). We performed a prospective evaluation of the accuracy of CC, compared with that of DIA and FISH, in detection of malignancy in patients undergoing endoscopic ultrasonography (EUS) fine-needle aspiration (FNA). METHODS: We collected a minimum of 6 FNA samples from each of 250 patients during EUS. CC or DIA and FISH analyses were performed on every other specimen (from every other FNA pass); patients were randomly assigned to the first test performed. CC slides were reviewed by gastrointestinal cytopathologists who were blinded to all data. Findings from cytohistologic analysis, after a minimum 24-month follow-up period, were used as the standard (n = 202; median age, 65 years). RESULTS: Aspirates were collected from lymph nodes (n = 111), pancreas (n = 61), gastrointestinal lumen wall (n = 9), periluminal mass (n = 4), liver (n = 8), and miscellaneous sites (n = 9). Matched samples provided a mean of 3.2 passes for CC and 1.6 passes for DIA and FISH. The data indicate a potential lack of utility for DIA. The combination of CC and FISH detected malignancy with 11% greater sensitivity than CC alone (P = .0002), but specificity was reduced from 100% to 96%. CONCLUSIONS: FISH analysis identifies neoplastic lesions with significantly greater sensitivity than CC in patients with diverse pathologies who underwent EUS with FNA, despite limited tissue sampling for FISH analysis.

Histologic and imaging features of mural nodules in mucinous pancreatic cysts.

BACKGROUND & AIMS: Mural nodules predict malignancy within pancreatic cysts, but it is not clear whether endoscopic ultrasound (EUS) and computed tomography (CT) accurately identify nodules. We assessed images and the histology of mural nodules in branch duct intraductal papillary mucinous neoplasms (BD-IPMNs) and mucinous cystic neoplasms (MCNs) and identified criteria to distinguish mural nodules from mucus. METHODS: We reviewed pathology specimens and EUS and CT images from consecutive patients with resected BD-IPMNs or MCNs. A blinded interobserver study of the EUS images was then conducted to identify features that distinguished nodules from mucus. After education about these features, the raters interpreted the EUS images again. RESULTS: On the basis of histologic analysis, 22 of 57 cases had epithelial nodules. Cancer or high-grade dysplasia was found in 23% of cysts with nodules versus 3% without nodules (P = .02). On the basis of reports, EUS detected epithelial nodules with 75% sensitivity and 83% specificity, whereas these values were 24% and 100%, respectively, for CT. Mucus accounted for 65% of intracystic lesions detected by EUS and was often diagnosed by using change in body position and fine-needle aspiration. Interobserver analysis identified 3 features that were detected by EUS (echogenicity, edge, and rim) that distinguished mucus from epithelial nodules. The diagnostic accuracy of the raters improved from a mean of 57% to 79% after education about these features (P = .004); accuracy was 90% when all 3 features of mucus were present. CONCLUSIONS: Malignancy is associated with epithelial nodules in BD-IPMNs and MCNs, but most echogenic lesions detected in cysts by EUS are mucus. Knowledge of features that discriminate mucus from mural nodules improves the diagnostic accuracy of EUS.

Demystifying seronegative autoimmune pancreatitis.

BACKGROUND: Autoimmune pancreatitis (AIP) has been classified into type 1 and type 2 subtypes. Serum immunoglobulin G4 (IgG4) elevation characterizes type 1 AIP. Type 2 AIP and a subset of type 1 AIP are seronegative, i.e., have normal serum IgG4 levels. AIM: We compared the profiles of the three subsets of AIP to identify the unique characteristics of seronegative type 1 AIP and type 2 AIP. METHODS: We compared the clinical profiles of 69 seropositive type 1 AIP patients, 21 seronegative type 1 AIP patients and 22 type 2 AIP patients. RESULTS: Among type 1 AIP, seronegative group had similar clinical profiles when compared to seropositive group except that they were more likely to undergo surgical resection than seropositive patients (p = 0.001). Seronegative type I AIP patients were older (61.9 ± 13.7 vs 45.3 ± 17.4; p = 0.004), and differed in the occurrence of other organ involvement (OOI) (71.4% vs 0%; p < 0.001) and disease relapse (33.3% vs 0%; p = 0.005) when compared with type 2 AIP. All seronegative type 1 AIP patients had at least one of the following -OOI, disease relapse, and age >50 years while none of the type 2 AIP had OOI or disease relapse. CONCLUSIONS: Seronegative and seropositive type 1 AIP patients have similar clinical profiles, which are distinct from that of type 2 AIP. Among the seronegative AIP group, patients are more likely to have type 1 AIP rather than type 2 AIP if they are older than 50 years or have OOI or disease relapse.

Local recurrence detection following transanal excision facilitated by EUS-FNA.

BACKGROUND/AIMS: Local excision is an alternative management approach for early rectal cancers and patients unfit for radical surgery. It is associated with a high local recurrence rate. Our aims were to evaluate the rate, pattern, method of local recurrence detection, the opportunity for salvage resection and finally to explore the utility of endoscopic ultrasound fine needle aspiration during surveillance. METHODOLOGY: A retrospective, non-controlled, cohort study from a single tertiary referral center comprised of patients undergoing surveillance following a transanal excision. RESULTS: Post-operative surveillance was performed in 155 transanal excision patients of which 46 (30%) underwent =1 endoscopic ultrasound examinations. Intra and extra luminal recurrence (n=16/24; (67%)) was detected more frequently in the endoscopic ultrasound surveillance population, p=0.0008. Mucosal scar biopsy (n=10/16;63%) and endoscopic ultrasound fine needle aspiration (6/16; 38%) of either a lymph node or the deep rectal wall were the methods for establishing local recurrence. An unremarkable proctoscopy with endoscopic ultrasound fine needle aspiration positive cytological findings was noted in 4 (9%) of the patients. CONCLUSIONS: Local recurrence following transanal excision is often in an intraluminal location. Endoscopic ultrasound fine needle aspiration confirmed nodal metastases in mesenteric and extra mesenteric locations more frequently than subepithelial locations.

Endoscopic retrograde pancreatography criteria to diagnose autoimmune pancreatitis: an international multicentre study.

BACKGROUND: Characteristic pancreatic duct changes on endoscopic retrograde pancreatography (ERP) have been described in autoimmune pancreatitis (AIP). The performance characteristics of ERP to diagnose AIP were determined. METHODS: The study was done in two phases. In phase I, 21 physicians from four centres in Asia, Europe and the USA, unaware of the clinical data or diagnoses, reviewed 40 preselected ERPs of patients with AIP (n=20), chronic pancreatitis (n=10) and pancreatic cancer (n=10). Physicians noted the presence or absence of key pancreatographic features and ranked the diagnostic possibilities. For phase II, a teaching module was created based on features found most useful in the diagnosis of AIP by the four best performing physicians in phase I. After a washout period of 3 months, all physicians reviewed the teaching module and reanalysed the same set of ERPs, unaware of their performance in phase I. RESULTS: In phase I the sensitivity, specificity and interobserver agreement of ERP alone to diagnose AIP were 44, 92 and 0.23, respectively. The four key features of AIP identified in phase I were (i) long (>1/3 the length of the pancreatic duct) stricture; (ii) lack of upstream dilatation from the stricture (<5 mm); (iii) multiple strictures; and (iv) side branches arising from a strictured segment. In phase II the sensitivity (71%) of ERP significantly improved (p<0.05) without a significant decline in specificity (83%) (p>0.05); the interobserver agreement was fair (0.40). CONCLUSIONS: The ability to diagnose AIP based on ERP features alone is limited but can be improved with knowledge of some key features.

Differences in clinical profile and relapse rate of type 1 versus type 2 autoimmune pancreatitis.

BACKGROUND & AIMS: Autoimmune pancreatitis (AIP) has been divided into subtypes 1 (lymphoplasmacytic sclerosing pancreatitis) and 2 (idiopathic duct centric pancreatitis). We compared clinical profiles and long-term outcomes of types 1 and 2 AIP. METHODS: We compared clinical presentation, relapse, and vital status of 78 patients with type 1 AIP who met the original HISORt criteria and 19 patients with histologically confirmed type 2 AIP. RESULTS: At presentation, patients with type 1 AIP were older than those with type 2 AIP (62 +/- 14 vs 48 +/- 19 years; P < .0001) and had a greater prevalence of increased serum levels of immunoglobulin G4 (47/59 [80%] vs 1/6 [17%]; P = .004). Patients with type 1 were more likely than those with type 2 to have proximal biliary, retroperitoneal, renal, or salivary disease (60% vs 0; P < .0001). Inflammatory bowel disease was associated with types 1 and 2 (6% vs 16%; P = .37). During median clinical follow-up periods of 42 and 29 months, respectively, 47% of patients with type 1 and none of those with type 2 experienced a relapse. In type 1 AIP, proximal biliary involvement (hazard ratio [HR], 2.12; P = .038) and diffuse pancreatic swelling (HR, 2.00; P = .049) were predictive of relapse, whereas pancreaticoduodenectomy reduced the relapse rate (vs the corticosteroid-treated group; HR, 0.15; P = .0001). After median follow-up periods of 58 and 89 months (types 1 and 2, respectively), the 5-year survival rates for both groups were similar to those of the age- and sex-matched US population. CONCLUSIONS: Types 1 and 2 AIP have distinct clinical profiles. Patients with type 1 AIP have a high relapse rate, but patients with type 2 AIP do not experience relapse. AIP does not affect long-term survival.

EUS-FNA assessment of extramesenteric lymph node status in primary rectal cancer.

BACKGROUND: Preoperative staging is an essential factor in the multidisciplinary management of rectal cancer. The accuracy of imaging alone with CT, magnetic resonance imaging, or rigid endorectal US is poor. The addition of EUS-FNA may enhance extramesenteric lymph node metastases detection (M1 disease) and overall staging accuracy. OBJECTIVE: To evaluate the frequency of extramesenteric lymph node visualization by EUS and the rate of extramesenteric lymph node metastases by FNA. Secondary goals were to evaluate the clinical, endoscopic, and sonographic features associated with extramesenteric lymph node metastases, disease progression, and overall mortality. DESIGN: Retrospective cohort study. SETTINGS: Tertiary referral center. RESULTS: Forty-one of 316 patients (13%) with primary rectal cancer over a 6-year period had M1 disease by EUS-FNA. Significant clinical, endoscopic, and sonographic features associated with extramesenteric lymph node metastases included the serum carcinoembryonic antigen level, tumor length 4 cm and longer, annularity 50% or more, sessile morphology, and lymph node size. The sensitivity and specificity of CT for extramesenteric lymph node metastases were 44% and 89%, respectively. Twenty-three of 316 rectal cancer endosonographic procedures (7.3%) were up-staged by FNA, which established extramesenteric lymph node metastases. Over a 4-year follow-up, disease progression and overall mortality of patients with extramesenteric lymph node metastases was observed in 6 patients (14.6%) and 14 patients (34%), respectively. CONCLUSIONS: Preoperative EUS-FNA identification of extramesenteric lymph node metastases outside of standard radiation fields or total mesorectal excision resection margins could affect medical and surgical planning.

False positive endoscopic ultrasound fine needle aspiration cytology: incidence and risk factors.

OBJECTIVE: It is broadly accepted that the false positive (FP) rate for endoscopic ultrasound fine needle aspiration (EUS FNA) is 0-1%. It was hypothesised that the FP and false suspicious (FS) rates for EUS FNA are greater than reported. A study was undertaken to establish the rate and root cause of discordant interpretation. DESIGN: Using a prospectively maintained endoscopic database, cytohistological discordant EUS FNA examinations from 30 July 1996 to 31 December 2008 were identified retrospectively. SETTING: Tertiary referral centre. MAIN OUTCOME MEASURES: Discordant FNA was defined by positive or suspicious FNA cytology in the absence of malignancy or neoplasm in the subsequent surgical pathology specimen, specifically in the absence of neoadjuvant therapy. Three cytopathologists conducted a blinded review of randomised discordant and matched specimens. RESULTS: FNA was performed in 5667/18 066 (31.4%) patients undergoing EUS, of whom 2547 had cytology results interpreted as 'positive' or 'suspicious' or 'atypical' for malignancy or neoplasm. Subsequent surgical resection without prior neoadjuvant therapy was performed in 377 patients with positive or suspicious cytology. The FP rate was 20/377 (5.3%) and increased to 27/377 (7.2%) when FS cases were included. The incidence of discordance was consistent over time (1996-2002: 10/118 (8.6%) vs 2003-2008: 17/259 (6.6%); p=0.5) and was higher in non-pancreatic FNA (15%) than pancreatic FNA (2.2%; p=0.0001). Two-thirds of the non-pancreatic FP cases involved sampling of perioesophageal or perirectal nodes in patients with luminal neoplasms or Barrett's oesophagus. Following pathological re-review, discordance was attributed to translocated cell contamination/sampling error (50%) or cytopathologist interpretive error (50%). CONCLUSIONS: These findings refute the accepted paradigm that FP cytology rarely occurs with EUS FNA. Further investigation revealed that FP FNA developed secondary to endosonographer technique or initial cytological misinterpretation, and is particularly likely when perioesophageal or perirectal nodes are aspirated in the setting of a luminal neoplasm or Barrett's oesophagus. Further study is needed to determine the significance of these findings and potential impact on the performance of FNA and patient outcomes.

Prevalence, diagnosis, and profile of autoimmune pancreatitis presenting with features of acute or chronic pancreatitis.

BACKGROUND & AIMS: Little is known about how many patients with features of acute pancreatitis (AP) or chronic pancreatitis (CP) have autoimmune pancreatitis (AIP); most information comes from case reports. We explored the clinical profiles and relationship between these diseases. METHODS: We evaluated 178 patients presenting to our Pancreas Clinic between January 2005 and June 2006 for evaluation of the etiology of their suspected pancreatitis; AIP was diagnosed when patients met HISORt (Histology, Imaging features, Serology, Other organ involvement and Response to steroid treatment) criteria. In a separate cohort of patients with AIP from our database, we identified patients who presented with features of AP (>/=2 of abdominal pain, increased pancreatic enzymes, pancreatic inflammation determined by imaging analyses) or CP (>/=1 of pancreatic calcification, irregular main pancreatic duct dilation, or marked atrophy) and determined their clinical profile. RESULTS: Only 7/178 (3.9%) patients evaluated for etiology of suspected pancreatitis had AIP. Among 63 AIP patients in our database, 22 (34.9%) had features of AP (n = 15) or CP (n = 7) at presentation (average age 53.4 +/- 19.0 years, all males). Patients with AIP and pancreatitis were characterized by presence of obstructive jaundice (59.1%), increased levels of liver enzymes (81.8%), increased levels of serum immunoglobulin G4 (80.9%), and other organ involvement (69.1%). All 19 patients presenting with pancreatitis who were treated with steroids responded to treatment. CONCLUSIONS: While AIP is an uncommon etiology for acute or chronic pancreatitis, >33% of AIP have features of acute or chronic pancreatitis at presentation.

Prospective cytological assessment of gastrointestinal luminal fluid acquired during EUS: a potential source of false-positive FNA and needle tract seeding.

OBJECTIVES: Endoscopic ultrasound (EUS) fine needle aspiration (FNA) can result in false-positive cytology and can also cause needle tract seeding. Our goal was to evaluate a potential cause, namely, the presence of malignant cells within gastrointestinal (GI) luminal fluid, either as a result of tumor sloughing from luminal cancers or secondary to FNA of extraluminal sites. METHODS: During EUS, luminal fluid that is usually aspirated through the echoendoscope suction channel and discarded was instead submitted for cytological analysis among patients with cancer and benign disease. Pre- and post-FNA luminal fluid samples were collected to discern the role of FNA in inducing a positive cytology. When not performing FNA, one sample was collected for the entire examination. The final diagnosis was based on strict clinicopathological criteria and >or=2-year follow-up. This study was conducted in a tertiary referral center. RESULTS: We assessed the prevalence of luminal fluid-positive cytology among patients with luminal (e.g., esophageal), extraluminal (e.g., pancreatic), and benign disease. Among the 140 patients prospectively enrolled with sufficient sampling and follow-up, an examination of luminal fluid cytology showed positive results for malignancy in luminal and extraluminal cancer patients, 48 and 10%, respectively. This included 8 out of 23 esophageal, 4 of 5 gastric, and 9 of 15 rectal cancers. The positive luminal fluid cytology rate with luminal cancers was not affected by performing FNA. Post-FNA luminal fluid cytology was positive in 3 out of 26 with pancreatic cancers. Cytological examination of luminal fluid aspirates did not demonstrate malignant cells in any patient with nonmalignant disease. CONCLUSIONS: Malignant cells are commonly present in the GI luminal fluid of patients with luminal cancers and can also be found in patients with pancreatic cancer after EUS FNA. Further study is needed to determine the impact of these findings on cytological interpretation, staging, risk of needle tract seeding, and patient care and outcomes.