Pancreatic Cysts Greater Than 1 cm Are Associated With an Increased Risk for Developing Pancreatic Cancer in Individuals From Pancreatic-Cancer Prone Kindreds Undergoing Surveillance

BACKGROUND

The International Cancer of the Pancreas Screening Consortium recommended annual imaging for individuals at increased risk for developing a pancreatic ductal adenocarcinoma (PDAC) who did not have concerning pancreatic findings or a cyst <3 cm without worrisome features. We aimed to determine if 3-cm cyst size accurately predicted advanced precursor lesions in high-risk individuals undergoing surveillance.

METHODS

Imaging for high-risk individuals (HRIs) undergoing PDAC surveillance from 2007 to 2021 was reviewed and pancreatic abnormalities were recorded including dominant cyst size and number of cysts. Subjects were excluded if they had the following: (1) no follow-up imaging after baseline, (2) solid lesion at baseline, or (3) development of solid lesion without having cyst on prior imaging.

RESULTS

Five of the 77 HRIs found to have a cystic lesion on surveillance developed a PDAC: 3 with cystic lesion >1 cm as compared with only 2 of 67 HRIs with cystic lesions <1 cm (P < 0.05). None of these cysts developed worrisome findings and 4/5 PDACs did not arise from visualized cystic precursor lesion.

CONCLUSIONS

Patients with a cyst ≥1 cm were at increased risk for developing PDAC compared with patients with cyst <1 cm. Pancreatic ductal adenocarcinoma usually did not arise from a recognized cystic lesion.

External nasal dilator decreases N95 respirator-related respiratory effort and symptoms in gastrointestinal endoscopy unit staff

Background and study aims  N95-filtering facepiece respirators (FFR) use is associated with physiological changes and symptoms due to impaired nasal airflow and increased breathing resistance. We prospectively studied the effect of using an external nasal dilator (END) in gastroenterology laboratory (gastrointestinal lab) staff using N95FFR. Patients and methods  N95FFR qualitative saccharine fit testing was performed on study participants with and without an END. Prospective data collection and comparisons included: 1) survey of perceived symptoms and difficulty of performing one day of gastrointestinal procedures with N95FFR and 1 day of gastrointestinal procedures with END plus N95FFR in random sequence; and 2) vitals and respiratory belt plethysmography in ten gastroenterologists performing simulated colonoscopy while wearing a surgical mask (SM), N95FFR plus SM, END plus N95FFR plus SM for 20 minutes each in random sequence and rapid succession. Results  Twenty-nine of 31 participants passed the N95FFR and the END plus N95FFR fit test. Twenty-two participants (12 physicians; 11 males; mean age 44.1 years, range 31-61) performed 1 day of gastrointestinal procedures with an N95FFR and 1 day of gastrointestinal procedures with an END plus N95FFR. Significantly less difficulty with nasal breathing and severity of symptoms including breathing difficulty, headache, fatigue and frustration, occurred while using an END plus N95FFR. Respiratory plethysmography peak-to-trough measurement showed an increase during the N95FFR stage compared to the END plus N95FFR stage and the SM stage. Conclusions  N95FFR related respiratory changes and symptom development may be mitigated by END use.

Non-functional pancreatic neuroendocrine tumours: ATRX/DAXX and alternative lengthening of telomeres (ALT) are prognostically independent from ARX/PDX1 expression and tumour size

OBJECTIVE

Recent studies have found aristaless-related homeobox gene (ARX)/pancreatic and duodenal homeobox 1 (PDX1), alpha-thalassemia/mental retardation X-linked (ATRX)/death domain-associated protein (DAXX) and alternative lengthening of telomeres (ALT) to be promising prognostic biomarkers for non-functional pancreatic neuroendocrine tumours (NF-PanNETs). However, they have not been comprehensively evaluated, especially among small NF-PanNETs (≤2.0 cm). Moreover, their status in neuroendocrine tumours (NETs) from other sites remains unknown.

DESIGN

An international cohort of 1322 NETs was evaluated by immunolabelling for ARX/PDX1 and ATRX/DAXX, and telomere-specific fluorescence in situ hybridisation for ALT. This cohort included 561 primary NF-PanNETs, 107 NF-PanNET metastases and 654 primary, non-pancreatic non-functional NETs and NET metastases. The results were correlated with numerous clinicopathological features including relapse-free survival (RFS).

RESULTS

ATRX/DAXX loss and ALT were associated with several adverse prognostic findings and distant metastasis/recurrence (p<0.001). The 5-year RFS rates for patients with ATRX/DAXX-negative and ALT-positive NF-PanNETs were 40% and 42% as compared with 85% and 86% for wild-type NF-PanNETs (p<0.001 and p<0.001). Shorter 5-year RFS rates for ≤2.0 cm NF-PanNETs patients were also seen with ATRX/DAXX loss (65% vs 92%, p=0.003) and ALT (60% vs 93%, p<0.001). By multivariate analysis, ATRX/DAXX and ALT status were independent prognostic factors for RFS. Conversely, classifying NF-PanNETs by ARX/PDX1 expression did not independently correlate with RFS. Except for 4% of pulmonary carcinoids, ATRX/DAXX loss and ALT were only identified in primary (25% and 29%) and NF-PanNET metastases (62% and 71%).

CONCLUSIONS

ATRX/DAXX and ALT should be considered in the prognostic evaluation of NF-PanNETs including ≤2.0 cm tumours, and are highly specific for pancreatic origin among NET metastases of unknown primary.

Tumor Size Differences Between Preoperative Endoscopic Ultrasound and Postoperative Pathology for Neoadjuvant-Treated Pancreatic Ductal Adenocarcinoma Predict Patient Outcome

BACKGROUND & AIMS

The assessment of therapeutic response after neoadjuvant treatment and pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) has been an ongoing challenge. Several limitations have been encountered when employing current grading systems for residual tumor. Considering endoscopic ultrasound (EUS) represents a sensitive imaging technique for PDAC, differences in tumor size between preoperative EUS and postoperative pathology after neoadjuvant therapy were hypothesized to represent an improved marker of treatment response.

METHODS

For 340 treatment-naïve and 365 neoadjuvant-treated PDACs, EUS and pathologic findings were analyzed and correlated with patient overall survival (OS). A separate group of 200 neoadjuvant-treated PDACs served as a validation cohort for further analysis.

RESULTS

Among treatment-naïve PDACs, there was a moderate concordance between EUS imaging and postoperative pathology for tumor size (r = 0.726, P < .001) and AJCC 8^th edition T-stage (r = 0.586, P < .001). In the setting of neoadjuvant therapy, a decrease in T-stage correlated with improved 3-year OS rates (50% vs 31%, P < .001). Through recursive partitioning, a cutoff of ≥47% tumor size reduction was also found to be associated with improved OS (67% vs 32%, P < .001). Improved OS using a ≥47% threshold was validated using a separate cohort of neoadjuvant-treated PDACs (72% vs 36%, P < .001). By multivariate analysis, a reduction in tumor size by ≥47% was an independent prognostic factor for improved OS (P = .007).

CONCLUSIONS

The difference in tumor size between preoperative EUS imaging and postoperative pathology among neoadjuvant-treated PDAC patients is an important prognostic indicator and may guide subsequent chemotherapeutic management.

Use of p53 immunohistochemistry in conjunction with routine histology improves risk stratification of patients with Barrett's oesophagus during routine clinical care

AIMS

Abnormal p53 protein expression detected by immunohistochemistry (IHC) in Barrett's oesophagus (BO) is reported to be a prognostic biomarker for progression to high-grade dysplasia (HGD) or oesophageal adenocarcinoma (OAC). We evaluated our use of p53 IHC for patients with BO under surveillance from 2010 to 2016 in a single academic institution.

METHODS AND RESULTS

We identified 78 patients under surveillance for BO who had biopsies evaluated for abnormal p53 expression in conjunction with routine histology and 892 patients who had histological evaluation alone. All available p53 IHC slides were rescored as wild-type or abnormal. We evaluated the risk of subsequent diagnosis with HGD and OAC. p53-tested patients were significantly more likely to be diagnosed with indefinite dysplasia (IND) or low-grade dysplasia (LGD), compared to patients who were not tested (79.5 versus 10.8%, P = 7.4 × 10^-40 ). Almost half (46.9%) of patients with abnormal p53 expression were diagnosed with HGD or OAC within 5 years, compared to 5.9% with wild-type p53, and 7.6% of patients not tested (P = 2.6 × 10^-18 ). However, this difference was heavily influenced by other risk factors, including dysplasia grade, in multivariate analyses. In the subgroup of patients diagnosed with IND (n = 109), abnormal p53 expression was associated with a fourfold increase (1.2-13.3, P = 0.023) in risk of HGD/OAC relative to untested patients diagnosed with IND, independent of other risk factors.

CONCLUSION

In patients under surveillance for BO in a single academic institution, we found evidence that selective use of p53 IHC in conjunction with routine histology modestly improved risk stratification by identifying patients with IND at higher risk of a subsequent diagnosis of HGD or OAC.

Recurrent Rearrangements in PRKACA and PRKACB in Intraductal Oncocytic Papillary Neoplasms of the Pancreas and Bile Duct

BACKGROUND & AIMS

Intraductal oncocytic papillary neoplasms (IOPNs) of the pancreas and bile duct contain epithelial cells with numerous, large mitochondria and are cystic precursors to pancreatic ductal adenocarcinoma (PDAC) and cholangiocarcinoma (CCA), respectively. However, IOPNs do not have the genomic alterations found in other pancreatobiliary neoplasms. In fact, no recurrent genomic alterations have been described in IOPNs. PDACs without activating mutations in KRAS contain gene rearrangements, so we investigated whether IOPNs have recurrent fusions in genes.

METHODS

We analyzed 20 resected pancreatic IOPNs and 3 resected biliary IOPNs using a broad RNA-based targeted sequencing panel to detect cancer-related fusion genes. Four invasive PDACs and 2 intrahepatic CCAs from the same patients as the IOPNs, were also available for analysis. Samples of pancreatic cyst fluid (n = 5, collected before surgery) and bile duct brushings (n = 2) were analyzed for translocations. For comparison, we analyzed pancreatobiliary lesions from 126 patients without IOPN (controls).

RESULTS

All IOPNs evaluated were found to have recurring fusions of ATP1B1-PRKACB (n = 13), DNAJB1-PRKACA (n = 6), or ATP1B1-PRKACA (n = 4). These fusions also were found in corresponding invasive PDACs and intrahepatic CCAs, as well as in matched pancreatic cyst fluid and bile duct brushings. These gene rearrangements were absent from all 126 control pancreatobiliary lesions.

CONCLUSIONS

We identified fusions in PRKACA and PRKACB genes in pancreatic and biliary IOPNs, as well as in PDACs and pancreatic cyst fluid and bile duct cells from the same patients. We did not identify these gene fusions in 126 control pancreatobiliary lesions. These fusions might be used to identify patients at risk for IOPNs and their associated invasive carcinomas.

Integrating next-generation sequencing to endoscopic retrograde cholangiopancreatography (ERCP)-obtained biliary specimens improves the detection and management of patients with malignant bile duct strictures

OBJECTIVE

Despite improvements in imaging, serum CA19-9 and pathological evaluation, differentiating between benign and malignant bile duct strictures remains a diagnostic conundrum. Recent developments in next-generation sequencing (NGS) have opened new opportunities for early detection and management of cancers but, to date, have not been rigorously applied to biliary specimens.

DESIGN

We prospectively evaluated a 28-gene NGS panel (BiliSeq) using endoscopic retrograde cholangiopancreatography-obtained biliary specimens from patients with bile duct strictures. The diagnostic performance of serum CA19-9, pathological evaluation and BiliSeq was assessed on 252 patients (57 trainings and 195 validations) with 346 biliary specimens.

RESULTS

The sensitivity and specificity of BiliSeq for malignant strictures was 73% and 100%, respectively. In comparison, an elevated serum CA19-9 and pathological evaluation had sensitivities of 76% and 48%, and specificities of 69% and 99%, respectively. The combination of BiliSeq and pathological evaluation increased the sensitivity to 83% and maintained a specificity of 99%. BiliSeq improved the sensitivity of pathological evaluation for malignancy from 35% to 77% for biliary brushings and from 52% to 83% for biliary biopsies. Among patients with primary sclerosing cholangitis (PSC), BiliSeq had an 83% sensitivity as compared with pathological evaluation with an 8% sensitivity. Therapeutically relevant genomic alterations were identified in 20 (8%) patients. Two patients with ERBB2-amplified cholangiocarcinoma received a trastuzumab-based regimen and had measurable clinicoradiographic response.

CONCLUSIONS

The combination of BiliSeq and pathological evaluation of biliary specimens increased the detection of malignant strictures, particularly in patients with PSC. Additionally, BiliSeq identified alterations that may stratify patients for specific anticancer therapies.

Preoperative next-generation sequencing of pancreatic cyst fluid is highly accurate in cyst classification and detection of advanced neoplasia

OBJECTIVE

DNA-based testing of pancreatic cyst fluid (PCF) is a useful adjunct to the evaluation of pancreatic cysts (PCs). Mutations in KRAS/GNAS are highly specific for intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs), while TP53/PIK3CA/PTEN alterations are associated with advanced neoplasia. A prospective study was performed to evaluate preoperative PCF DNA testing.

DESIGN

Over 43-months, 626 PCF specimens from 595 patients were obtained by endoscopic ultrasound (EUS)-fine needle aspiration and assessed by targeted next-generation sequencing (NGS). Molecular results were correlated with EUS findings, ancillary studies and follow-up. A separate cohort of 159 PCF specimens was also evaluated for KRAS/GNAS mutations by Sanger sequencing.

RESULTS

KRAS/GNAS mutations were identified in 308 (49%) PCs, while alterations in TP53/PIK3CA/PTEN were present in 35 (6%) cases. Based on 102 (17%) patients with surgical follow-up, KRAS/GNAS mutations were detected in 56 (100%) IPMNs and 3 (30%) MCNs, and associated with 89% sensitivity and 100% specificity for a mucinous PC. In comparison, KRAS/GNAS mutations by Sanger sequencing had a 65% sensitivity and 100% specificity. By NGS, the combination of KRAS/GNAS mutations and alterations in TP53/PIK3CA/PTEN had an 89% sensitivity and 100% specificity for advanced neoplasia. Ductal dilatation, a mural nodule and malignant cytopathology had lower sensitivities (42%, 32% and 32%, respectively) and specificities (74%, 94% and 98%, respectively).

CONCLUSIONS

In contrast to Sanger sequencing, preoperative NGS of PCF for KRAS/GNAS mutations is highly sensitive for IPMNs and specific for mucinous PCs. In addition, the combination of TP53/PIK3CA/PTEN alterations is a useful preoperative marker for advanced neoplasia.

Loss of Chromatin-Remodeling Proteins and/or CDKN2A Associates With Metastasis of Pancreatic Neuroendocrine Tumors and Reduced Patient Survival Times

Despite prognostic grading and staging systems, it is a challenge to predict outcomes for patients with pancreatic neuroendocrine tumors (PanNETs). Sequencing studies of PanNETs have identified alterations in death domain-associated protein (DAXX) and alpha-thalassemia/mental retardation X-linked chromatin remodeler (ATRX). In tumors, mutations in DAXX or ATRX and corresponding loss of protein expression correlate with shorter times of disease-free survival and disease-specific survival of patients. However, DAXX or ATRX proteins were lost in only 50% of distant metastases analyzed. We performed whole-exome sequencing analyses of 20 distant metastases from 20 patients with a single nonsyndrome, nonfunctional PanNET. We found distant metastases contained alterations in multiple endocrine neoplasia type 1 (MEN1) (n = 8), ATRX (n = 5), DAXX (n = 5), TSC2 (n = 3), and DEP domain containing 5 (DEPDC5) (n = 3). We found copy number loss of cyclin dependent kinase inhibitor 2A (CDKN2A) in 15 metastases (75%) and alterations in genes that regulate chromatin remodeling, including set domain containing 2 (SETD2) (n = 4), AT-rich interaction domain 1A (ARID1A) (n = 2), chromodomain helicase DNA binding protein 8 (CHD8) (n = 2), and DNA methyl transferase 1 (DNMT1) (n = 2). In a separate analysis of 347 primary PanNETs, we found loss or deletion of DAXX and ATRX, disruption of SETD2 function (based on loss of H3 lysine 36 trimethylation), loss of ARID1A expression or deletions in CDKN2A in 81% of primary PanNETs with distant metastases. Among patients with loss or deletion of at least 1 of these proteins or genes, 39% survived disease-free for 5 years and 44% had disease-specific survival times of 10 years. Among patients without any of these alterations, 98% survived disease-free for 5 years and 95% had disease-specific survival times of 10 years. Therefore, primary PanNETs with loss of DAXX, ATRX, H3 lysine 36 trimethylation, ARID1A, and/or CDKN2A associate with shorter survival times of patients. Our findings indicate that alterations in chromatin-remodeling genes and CDKN2A contribute to metastasis of PanNETs.

Lymphoepithelial cyst of pancreas: spectrum of radiological findings with pathologic correlation

PURPOSE

The purpose of the study was to investigate imaging features as well as pathologic and clinical findings of lymphoepithelial cyst (LEC) of pancreas.

MATERIALS AND METHODS

Ten patients with surgically resected and pathologically proven LEC, found in a single institution database between 2000 and 2015, were evaluated in a retrospective fashion. Patients' demographics, clinical presentation, co-morbidities, imaging features, cytology and histopathology results, and serum/aspirate biomarkers levels were recorded.

RESULTS

Eighty percent of patients were male with median age of 59. All lesions were exophytic, with median size of 36 mm. 80% were classified as complex cystic lesions, showing enhancing septa or enhancing rim without measurable enhancing solid component. 80% were located in tail or body. In one patient with MRI, the lesion was mildly T1 hyperintense and markedly T2 hyperintense. All cases were anechoic or hypoechoic on EUS, and majority of them showed posterior acoustic enhancement. Of patients with available fluid aspirate analysis, 3 out of 4 had CEA level > 192 ng/mL and 1 out of 3 had elevated (>250 IU/ml) amylase level. Four out of 7 patients had elevated serum CA 19-9 levels (>37 U/mL); one patient with a value of 361 U/mL had co-existing pancreatic adenocarcinoma.

CONCLUSION

Round shape, mild complexity, and exophytic location in pancreatic body and tail can be suggestive of LECs. These features however are not specific and may be seen with other cystic pancreatic lesions. CT findings should be used in conjunction with EUS, cytology, and tumor marker studies to secure the diagnosis of LEC.

American Gastroenterological Association guidelines are inaccurate in detecting pancreatic cysts with advanced neoplasia: a clinicopathologic study of 225 patients with supporting molecular data

BACKGROUND AND AIMS

The American Gastroenterological Association (AGA) recently reported evidence-based guidelines for the management of asymptomatic neoplastic pancreatic cysts. These guidelines advocate a higher threshold for surgical resection than prior guidelines and imaging surveillance for a considerable number of patients with pancreatic cysts. The aims of this study were to assess the accuracy of the AGA guidelines in detecting advanced neoplasia and present an alternative approach to pancreatic cysts.

METHODS

The study population consisted of 225 patients who underwent EUS-guided FNA for pancreatic cysts between January 2014 and May 2015. For each patient, clinical findings, EUS features, cytopathology results, carcinoembryonic antigen analysis, and molecular testing of pancreatic cyst fluid were reviewed. Molecular testing included the assessment of hotspot mutations and deletions for KRAS, GNAS, VHL, TP53, PIK3CA, and PTEN.

RESULTS

Diagnostic pathology results were available for 41 patients (18%), with 13 (6%) harboring advanced neoplasia. Among these cases, the AGA guidelines identified advanced neoplasia with 62% sensitivity, 79% specificity, 57% positive predictive value, and 82% negative predictive value. Moreover, the AGA guidelines missed 45% of intraductal papillary mucinous neoplasms with adenocarcinoma or high-grade dysplasia. For cases without confirmatory pathology, 27 of 184 patients (15%) with serous cystadenomas (SCAs) based on EUS findings and/or VHL alterations would continue magnetic resonance imaging (MRI) surveillance. In comparison, a novel algorithmic pathway using molecular testing of pancreatic cyst fluid detected advanced neoplasias with 100% sensitivity, 90% specificity, 79% positive predictive value, and 100% negative predictive value.

CONCLUSIONS

The AGA guidelines were inaccurate in detecting pancreatic cysts with advanced neoplasia. Furthermore, because the AGA guidelines manage all neoplastic cysts similarly, patients with SCAs will continue to undergo unnecessary MRI surveillance. The results of an alternative approach with integrative molecular testing are encouraging but require further validation.

Human polyomavirus 7-associated pruritic rash and viremia in transplant recipients

Human polyomavirus 7 (HPyV7) is one of 11 HPyVs recently discovered through genomic sequencing technologies. Two lung transplant recipients receiving immunosuppressive therapy developed pruritic, brown plaques on the trunk and extremities showing a distinctive epidermal hyperplasia with virus-laden keratinocytes containing densely packed 36-45-nm icosahedral capsids. Rolling circle amplification and gradient centrifugation testing were positive for encapsidated HPyV7 DNA in skin and peripheral blood specimens from both patients, and HPyV7 early and capsid proteins were abundantly expressed in affected tissues. We describe for the first time that HPyV7 is associated with novel pathogenicity in some immunosuppressed individuals.

Preoperative GNAS and KRAS testing in the diagnosis of pancreatic mucinous cysts

PURPOSE

Management guidelines for pancreatic intraductal papillary mucinous neoplasms (IPMN) and mucinous cystic neoplasms (MCN) are based on the assumption that mucinous cysts can be accurately distinguished from other pancreatic cystic lesions. Previous studies using surgical material have identified recurrent mutations in GNAS and KRAS in pancreatic mucinous neoplasms. Yet, the diagnostic utility of testing for both genes in pancreatic cyst fluid obtained by endoscopic ultrasound-fine-needle aspiration (EUS-FNA) remains unclear.

EXPERIMENTAL DESIGN

GNAS and KRAS testing was performed on EUS-FNA pancreatic cyst fluid from 91 pancreatic cysts: 41 IPMNs, 9 IPMNs with adenocarcinoma, 16 MCNs, 10 cystic pancreatic neuroendocrine tumors (PanNET), 9 serous cystadenomas (SCA), 3 retention cysts, 2 pseudocysts, and 1 lymphoepithelial cyst.

RESULTS

Mutations in GNAS were detected in 16 (39%) IPMNs and 2 (22%) IPMNs with adenocarcinoma. KRAS mutations were identified in 28 (68%) IPMNs, 7 (78%) IPMNs with adenocarcinoma, and 1 (6%) MCN. Mutations in either gene were present in 34 (83%) IPMNs, 8 (89%) IPMNs with adenocarcinoma, and 1 (6%) MCN. No mutations were found in cystic PanNETs, SCAs, retention cysts, pseudocysts, and a lymphoepithelial cyst. GNAS and KRAS mutations had 100% specificity [95% confidence interval (CI), 0.83-1.00] but 65% sensitivity (95% CI, 0.52-0.76) for mucinous differentiation. Among IPMNs, mutations in either gene had 98% specificity (95% CI, 0.86-1.00) and 84% sensitivity (95% CI, 0.70-0.92).

CONCLUSIONS

The combination of GNAS and KRAS testing was highly specific and sensitive for IPMNs; however, the lack of sensitivity for MCNs highlights the need for additional markers to improve the detection of pancreatic mucinous neoplasms.

Integration of KRAS testing in the diagnosis of pancreatic cystic lesions: a clinical experience of 618 pancreatic cysts

With improvements in abdominal imaging, detection of incidental pancreatic cysts are becoming increasingly common. Analysis of pancreatic cyst fluid from fine-needle aspiration is particularly important in identifying intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs), which have significant implications in clinical intervention and follow-up. Previous controlled studies have shown that KRAS mutations in cyst fluid are highly specific for mucinous differentiation in pancreatic cysts; however, this has not been examined in the clinical setting. Over a 6-year study period, 618 pancreatic cyst fluids obtained by fine-needle aspiration at the time of endoscopic ultrasound were tested for KRAS mutations as part of routine evaluation for a cystic neoplasm. Of the 618 specimens, 603 (98%) from 546 patients were satisfactory for molecular analysis. Patients ranged in age from 17 to 90 years (mean, 63.9 years) and were predominantly female (68%). Pancreatic cysts were relatively evenly distributed throughout the pancreas and ranged in size from 0.6 to 11.0 cm (mean, 2.3 cm). Mutations in KRAS were detected in 232 of 603 (38%) aspirates. Although sufficient for molecular analysis, 320 of 603 (53%) specimens were either less than optimal (38%) or unsatisfactory (15%) for cytopathologic diagnosis. Surgical follow-up information was available for 142 (26%) patients and consisted of 53 KRAS-mutated and 89 KRAS-wild-type cysts. Overall, KRAS mutations had a specificity of 100%, but a sensitivity of 54% for mucinous differentiation. When stratified by cyst type, KRAS had a sensitivity of 67% and 14% for IPMNs and MCNs, respectively. In summary, KRAS mutations were highly specific for mucinous differentiation, but were inadequate in identifying MCNs. Future molecular studies and the combination of other fluid markers are required to improve the detection and classification of pancreatic mucinous neoplasms by endoscopic ultrasound fine-needle aspiration.

Nuclear Nano-architecture Markers of Gastric Cardia and Upper Squamous Esophagus Detect Esophageal Cancer "Field Effect"

Background: Barrett's esophagus (BE) affects up to 12 million Americans and confers an increased risk for development of esophageal adenocarcinoma (EAC). EAC is often fatal unless detected early. Given the high prevalence, high cost of surveillance and relatively low risk of most affected individuals, identification of high-risk patients for additional scrutiny, regular surveillance, or ablative therapy is crucial. The exploration of “field effect” by probing uninvolved esophageal mucosa to predict the risk of EAC has the potential as an improved surveillance and prevention strategy. In this study, we evaluate the ability of nuclear nano-architecture markers from normal squamous esophagus and gastric cardia to detect the “field effect” of esophageal dysplasia and EAC, and their response to endoscopic therapy.

Methods: Patients with normal esophagus, gastroesophageal reflux, BE and EAC were eligible for enrollment. We performed endoscopic cytology brushings of the gastric cardia, ~1-2 cm below the gastroesophageal junction, and of the normal squamous esophageal mucosa at ~20 cm from the incisors and standard cytology slides were made using Thinprep method. Optical analysis was performed on the cell nuclei of cytologically normal-appearing epithelial cells.

Results: The study cohort consisted of 128 patients. The nuclear nano-architecture markers detected the presence of esophageal dysplasia and EAC with statistical significance. The field effect does not exhibit a spatial dependence. These markers reverted toward normal in response to endoscopic therapy.

Conclusions: Optical analysis of gastric cardia and upper squamous esophagus represents a potentially viable method to improve risk stratification and ease of surveillance of patients with Barrett's esophagus and to monitor the efficacy of ablative therapy.

Endotherapy for superficial adenocarcinoma of the esophagus: an American experience

BACKGROUND

EMR and ablation are increasingly being used alone or in combination for treatment of Barrett's neoplasia. Given a very low rate of lymph node metastasis, endotherapy has become an accepted treatment option for T1a esophageal adenocarcinoma (EAC) with low-risk features.

OBJECTIVE

To report our experience of endoscopic management of T1a EAC in a large, tertiary-care center.

DESIGN

Retrospective review.

SETTING

Tertiary-care referral center.

PATIENTS

Patients treated endoscopically for low-risk T1a EAC at our center.

INTERVENTION

EMR and endoscopic ablation.

MAIN OUTCOME MEASUREMENTS

Death related to esophageal cancer, remission of adenocarcinoma, dysplasia, and intestinal metaplasia.

RESULTS

A total of 54 patients underwent endotherapy for low-risk T1a EAC from 2006 to 2012. Mean (± SD) follow-up was 23 (± 16) months, mean (± SD) size of resected adenocarcinoma was 7.1 (± 4.3) mm, and mean (± SD) Barrett's esophagus length was 4.5 (± 3.9) cm. Band-assisted, cap-assisted, and lift and cut EMR were performed in 85%, 11%, and 4% of patients, respectively; 81% underwent additional ablative therapy (radiofrequency ablation 95%, cryotherapy 9%, photodynamic therapy 2%). Complete remission from cancer was achieved in 96%, complete remission from dysplasia in 87%, and complete remission from intestinal metaplasia in 59%. The overall survival was 89%; there were no deaths related to esophageal cancer.

LIMITATIONS

Retrospective study.

CONCLUSION

Endotherapy for T1a EAC was safe and effective in our American cohort. Endotherapy should be considered primary therapy for appropriate patients with low-risk lesions. Complete Barrett's esophagus eradication after EMR is important to reduce the development of metachronous lesions.

Association between KRAS mutation, detected in pancreatic cyst fluid, and long-term outcomes of patients

BACKGROUND & AIMS

Endoscopic ultrasound (EUS) with fine-needle aspiration is routinely used to evaluate pancreatic cysts. We investigated the association between results from DNA analysis of cyst fluid and patient outcomes.

METHODS

In a retrospective analysis, we collected data from 113 patients with pancreatic cysts who underwent EUS with fine-needle aspiration at a tertiary care center from June 2004 to June 2007. Detailed follow-up data were obtained through October 2010 (mean, 47 months). Pancreatic cysts were categorized as nonbenign or benign on the basis of pathology analysis of surgical samples and patients' outcomes. We compared the patient characteristics, presenting symptoms, EUS imaging characteristics, and results from analysis of cyst fluid, including cytology results, levels of carcinoembryonic antigen, and DNA sequencing results.

RESULTS

Fifty-one patients underwent pancreatic surgery (10 had malignant, 18 had mucinous, and 16 had benign cysts), 63 patients were followed long-term, and 13 patients died of pancreatic cancer. On the basis of multivariate regression analysis, the presence of cyst solid component, patient symptoms, cyst size >3 cm, and detection of KRAS mutations at codons 12 and 13 in cyst fluid were independently associated with a nonbenign course.

CONCLUSIONS

KRAS mutations, detected in pancreatic cyst fluid, are associated with mucinous cysts and progression and development of malignancy and should be considered in assessing pancreatic cysts. The presence of a cyst solid component, patient symptoms, and cyst size greater than 3 cm were additional high-risk factors for a malignant course of disease.

Gallbladder agenesis

Gallbladder agenesis is a rare entity with an estimated incidence of 10-65 per 100,000. Females are more commonly affected (ratio 3:1), typically presenting in the 2nd or 3rd decade of life. Despite an absent gallbladder, half of patients present with symptoms similar to biliary colic, which is poorly understood. Clinicians should have a strong index of suspicion if nonvisualization is suggested by an ultrasound. HIDA scans are typically not helpful since nonvisualization of the gallbladder remains typical of cystic duct obstruction as well as of agenesis. While there are no specific guidelines for management of gallbladder agenesis, conservative management with smooth muscle relaxants is preferred. Sphincterotomy also has been reported in severe cases. Here, we report a case of a 21-year-old woman who presented with recurrent biliary colic and was diagnosed to have gallbladder agenesis on magnetic resonance cholangiopancreatography. A comparison with other cases and a review of the literature are presented.

EUS-FNA mutational analysis in differentiating autoimmune pancreatitis and pancreatic cancer

BACKGROUND/AIMS

Autoimmune pancreatitis (AIP) may mimic pancreatic cancer (PC). The detection of DNA mutations in endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) material may improve discrimination between AIP and PC and is the context for this study.

METHODS

In a retrospective study, archived EUS-FNA material from patients with AIP and PC at two centers was analyzed for KRAS mutations and loss-of-heterozygosity analysis involving 18 microsatellite markers. KRAS status and the fractional allelic loss (number of affected microsatellites divided by informative ones) were compared for AIP and PC.

RESULTS

Thirty-two patients with 33 samples were studied. There were 16 patients with AIP (17 samples) and 16 patients with PC. DNA amplification failed in 7 samples. Of 25 patients (26 samples), 14 had AIP (7 male, age 57 ± 17 years; mean ± SD) and 11 had PC (7 male, age 65 ± 14 years; mean ± SD). Cytology results for AIP were inflammatory = 3, inconclusive = 10, suspicious for malignancy = 2 and for PC were malignant = 5, suspicious for malignancy = 4 and inconclusive = 2, respectively. KRAS mutation was detected in none of the AIP cases and 10/11 PC cases (91%, Pearson χ(2) = 22.16, p < 0.001) or 10/16 PC cases (63%) accounting for PC cases with failed DNA amplification. Mean (±SD) fractional allelic loss for the AIP cases (0.16 ± 0.15) was not significantly different from the PC cases (0.26 ± 0.19).

CONCLUSIONS

A KRAS mutation in EUS/FNA material from a pancreatic mass is associated with malignancy and may help discriminate from benign conditions such as AIP.

DNA mutational differences in cytological specimens from pancreatic cancer and cholangiocarcinoma

BACKGROUND/AIMS

Preoperative distinction between pancreatic cancer (PC) and extrahepatic cholangiocarcinoma (CC) is desirable due to diverging management options, and to optimize enrollment into neoadjuvant trials.

METHODS

A single-center retrospective study of patients with PC or CC was undertaken. Four blinded pathologists reviewed all cases and reached a consensus diagnosis (PC or CC). Microdissection-based multiple microsatellite loss analysis and direct sequencing of K-ras oncogene was performed and compared for PC and CC.

RESULTS

Of 33 cases studied (17 males; 16 PC, 17 CC; 10 with primary sclerosing cholangitis), a K-ras mutation was present in 14/16 (87.5%) PC and 1/17 (5.9%) CC cases (p < 0.001), sensitivity and specificity were 87.5 and 94%, respectively. The mean fractional mutational rate was higher in PC (0.51; 95% CI 0.45-0.58) compared to CC (0.34; 95% CI 0.28-0.39, p < 0.001).

CONCLUSIONS

The presence of a K-ras mutation in cytology specimens distinguishes PC from CC in this study. and IAP.

Pancreatic endocrine tumor EUS-guided FNA DNA microsatellite loss and mortality

BACKGROUND

The clinical course of pancreatic endocrine tumors (PET) depends on tumor size, the presence of invasion or metastasis, the Ki-67 index, mitoses per high power field, and mutational damage. Most of this information is not available before surgery for clinical decision making or prognostication.

OBJECTIVE

To evaluate PET EUS-guided FNA (EUS-FNA) microsatellite loss analysis in the context of PET-related mortality.

DESIGN

A single institution retrospective cohort.

PATIENTS

Patients with PET diagnosed by EUS-FNA who underwent DNA microsatellite loss analysis and at least 1 year of follow-up or subsequent death.

INTERVENTION

PET microsatellite loss analysis results and current clinical status were compared.

RESULTS

Twenty-nine patients were included in the final analysis; the mean age of the patients was 57 years, and 10 were women (35%). The mean follow-up was 33.7 months (median 30 months, range 2-66 months). Twelve patients had disease progression, and 8 died, all from disease-specific causes. Malignant PET contained multiple microsatellite losses, with a median fractional allelic loss (FAL) of 0.37 (range 0.12-0.69, interquartile range [IQR] 0.23-0.42), significantly different from benign PET, median FAL 0 (range 0-0.18, IQR 0-0.08, P < .0001). Survival analysis revealed a significant difference in disease recurrence or progression at 2 years (P < .0001) and in the 5-year survival between patients with FAL </=0.2 compared with >0.2 (P < .0001). Logistic regression could not be performed because of the perfect association between an FAL >0.2 and disease status or mortality.

LIMITATIONS

Retrospective design, referral bias, and DNA analysis availability.

CONCLUSIONS

PET EUS-FNA microsatellite loss analysis provides preoperative prognostic information. An FAL >0.2 is not only associated with disease progression but also with mortality.

Cystic lesions and intraductal neoplasms of the pancreas

Pancreatic cystic lesions are being detected more frequently given increased use of cross-sectional imaging modalities. The most common cysts encountered are mucinous cysts, which have malignant potential. As many of these lesions are incidental findings, it is important to further evaluate them with endoscopic ultrasound-guided fine needle aspiration for diagnostic purposes and risk stratification. These cysts either require surgical resection or surveillance given the malignant risk. Mucinous cystic neoplasms should be resected. Intraductal papillary mucinous neoplasia (IPMN) has consensus-guideline indications for resection. These include main duct diameter > or = 10 mm, a branch duct size > or = 3 cm, presence of a mural nodule, or cytology suspicious for malignancy. Additionally, all symptomatic cysts, regardless of etiology, should undergo resection. Branch duct IPMN is less aggressive that the main duct variety, and may be conservatively followed. However, the development of an established indication for resection should prompt surgery. Despite generalized guidelines, decisions regarding management of pancreatic cysts should be individualized, accounting for the malignant risk of the lesion and the surgical risk of the patient.

Distribution and neurochemical identification of pancreatic afferents in the mouse

Dysfunction of primary afferents innervating the pancreas has been shown to contribute to the development of painful symptoms during acute and chronic pancreatitis. To investigate the distribution and neurochemical phenotype of pancreatic afferents, Alexa Fluor-conjugated cholera toxin B (CTB) was injected into the pancreatic head (CTB-488) and tail (CTB-555) of adult male mice to label neurons retrogradely in both the dorsal root ganglia (DRG) and nodose ganglia (NG). The NG and DRG (T5-T13) were processed for fluorescent immunohistochemistry and visualized by using confocal microscopy. Spinal pancreatic afferents were observed from T5 to T13, with the greatest contribution coming from T9-T12. The pancreatic afferents were equally distributed between right and left spinal ganglia; however, the innervation from the left NG was significantly greater than from the right. For both spinal and vagal afferents there was significantly greater innervation of the pancreatic head relative to the tail. The total number of retrogradely labeled afferents in the nodose was very similar to the total number of DRG afferents. The neurochemical phenotype of DRG neurons was dominated by transient receptor potential vanilloid 1 (TRPV1)-positive neurons (75%), GDNF family receptor alpha-3 (GFRalpha3)-positive neurons (67%), and calcitonin gene-related peptide (CGRP)-positive neurons(65%) neurons. In the NG, TRPV1-, GFRalpha3-, and CGRP-positive neurons constituted only 35%, 1%, and 15% of labeled afferents, respectively. The disparity in peptide and receptor expression between pancreatic afferents in the NG and DRG suggests that even though they contribute a similar number of primary afferents to the pancreas, these two populations may differ in regard to their nociceptive properties and growth factor dependency.

Pain in chronic pancreatitis and pancreatic cancer

Chronic, debilitating abdominal pain is arguably the most important component of chronic pancreatitis, leading to significant morbidity and disability. Attempting to treat this pain, which is too often unsuccessful, is a frustrating experience for physician and patient. Multiple studies to improve understanding of the pathophysiology that causes pain in some patients but not in others have been performed since the most recent reviews on this topic. In addition, new treatment modalities have been developed and evaluated in this population. This review discusses new advances in neuroscience and the study of visceral pain mechanisms, as well as genetic factors that may play a role. Updates of established therapies, as well as new techniques used in addressing pain from chronic pancreatitis, are reviewed. Lastly, outcome measures, which have been highly variable in this field over the years, are addressed.