EUS and EUS-FNA diagnosis of suspected pancreatic cystic neoplasms: Is the sum of the parts greater than the CEA?

Predictive ability of pancreatic cyst fluid biomarkers: A systematic review and meta-analysis

BACKGROUND

Mucinous pancreatic cysts harbor the potential to progress to highly lethal pancreatic ductal adenocarcinoma (PDAC). Since these precursor cysts require cancer surveillance or surgical resection, they need to be reliably distinguished from harmless pancreatic cysts. Current clinical and radiographic assessment is imperfect and the value of cyst fluid analysis for differential diagnosis is unclear. Therefore, we set out to investigate the value of cyst fluid biomarkers in distinguishing pancreatic cysts.

METHODS

We performed a systematic review of the current literature to identify articles that evaluated the diagnostic performance of clinically relevant and promising candidate cyst fluid biomarkers, with a particular emphasis on DNA-based biomarkers. Meta-analysis was performed for biomarkers targeted at identifying cyst type and presence of high-grade dysplasia or PDAC.

RESULTS

Data from a total of 42 studies was analyzed. Mutations in KRAS and/or GNAS allowed identification of mucinous cysts with a sensitivity of 79% and specificity of 98%. This exceeded the performance of the traditional biomarker carcinoembryonic antigen (CEA; sensitivity 58%, specificity 87%). Mutations in VHL were specific for serous cystadenomas (SCAs; sensitivity 56%, specificity 99%) and help to exclude mucinous cysts. Mutations in CDKN2A, PIK3CA, SMAD4, and TP53 each had high specificities of 97%, 97%, 98%, and 95%, respectively, to identify high-grade dysplasia or PDAC in mucinous cysts.

CONCLUSIONS

Cyst fluid analysis can be a valuable tool in the characterization of pancreatic cysts, with relevant clinical implications. Our results support the use of DNA-based cyst fluid biomarkers in the multidisciplinary diagnostic work-up of pancreatic cysts.

Is antibiotic prophylaxis necessary after endoscopic ultrasound-guided fine-needle aspiration of pancreatic cysts?

BACKGROUND/AIMS

Current society guidelines recommend antibiotic prophylaxis for 3 to 5 days after endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of pancreatic cystic lesions (PCLs). The overall quality of the evidence supporting this recommendation is low. In this study, we aimed to assess cyst infection and adverse event rates after EUS-FNA of PCLs among patients treated with or without postprocedural prophylactic antibiotics.

METHODS

We retrospectively reviewed all patients who underwent EUS-FNA of PCLs between 2015 and 2019 at two large-volume academic medical centers with different practice patterns of postprocedural antibiotic prophylaxis. Data on patient demographics, cyst characteristics, fine-needle aspiration technique, periprocedural and postprocedural antibiotic prophylaxis, and adverse events were retrospectively extracted.

RESULTS

A total of 470 EUS-FNA procedures were performed by experienced endosonographers for the evaluation of PCLs in 448 patients, 58.7% of whom were women. The mean age was 66.3±12.8 years. The mean cyst size was 25.7±16.9 mm. Postprocedural antibiotics were administered in 274 cases (POSTAB+ group, 58.3%) but not in 196 cases (POSTAB- group, 41.7%). None of the patients in either group developed systemic or localized infection within the 30-day follow-up period. Procedure-related adverse events included mild abdominal pain (8 patients), intra-abdominal hematoma (1 patient), mild pancreatitis (1 patient), and perforation (1 patient). One additional case of pancreatitis was recorded; however, the patient also underwent endoscopic retrograde cholangiopancreatography.

CONCLUSION

The incidence of infection after EUS-FNA of PCLs is negligible. Routine use of postprocedural antibiotics does not add a significant benefit.

Clinical Utility of the Contrast-Enhanced Endoscopic Ultrasound Guided Fine Needle Aspiration in the Diagnosis of Pancreatic Cyst

Endoscopic ultrasound fine needle aspiration (EUS-FNA) cytology from an intracystic fluid is useful in the differentiation of pancreatic cysts, with low sensitivity, which increases when the solid component is targeted. The clinical utility of contrast-enhanced guided EUS-FNA (CH-EUS-FNA) in the solid component is not known. We aimed to assess the diagnostic value of CH-EUS-FNA in enhanced mural nodules and discrimination between different cysts using contrast-enhanced endoscopic ultrasound (CH-EUS). The prospective study recruited patients with pancreatic cysts with an unclear diagnosis. The CH-EUS was followed by CH-EUS-FNA. The final diagnosis was based on surgery or the correlation between clinical history, cross-sectional imaging, echoendoscopic morphology, cystic fluid analysis, and follow-up. Fifty-eight patients with pancreatic cysts were evaluated. The mucinous cysts had wall arterial enhancement more often than non- mucinous cysts (p < 0.0001), with 90.2% sensitivity and 70.6% specificity. The CH-EUS-FNA from cystic fluid and mural nodules identified mucinous cysts and malignancy with 82.4% and 84.2% sensitivity and 92% and 100% specificity. Twenty-one cysts had solid components, but only 13 were enhanced mural nodules on EUS assessment with conclusive cytology in all cases and malignancy in 76.9%. Contrast-enhanced endoscopic ultrasound should be completed in all PCN with solid components in order to avoid unnecessary EUS-FNA and to guide FNA for the identification of malignant cysts.

Utility of Cyst Fluid Carcinoembryonic Antigen in Differentiating Mucinous and Non-mucinous Pancreatic Cysts: An Updated Meta-Analysis

BACKGROUND

Mucinous pancreatic cysts are considered premalignant and managed differently compared to benign pancreatic cystic lesions. The aim of this updated meta-analysis is to assess the diagnostic accuracy of cyst carcinoembryonic antigen (CEA) in differentiating between mucinous and non-mucinous pancreatic cysts.

METHODS

Studies comparing the diagnostic accuracy of CEA (cutoff level of 192 ng/mL) in differentiating between mucinous and non-mucinous pancreatic cysts were searched in Medline, Ovid journals, Medline nonindexed citations, and Cochrane Central Register of Controlled Trials and Database of Systematic Reviews. Pooled estimates of diagnostic precision were calculated using random and fixed effects models.

RESULTS

Initial search identified 526 reference articles, of these 34 relevant articles were selected and reviewed. Data were extracted from 15 studies (n = 2063) which met the inclusion criteria. The pancreatic cystic fluid CEA level at a 192 ng/mL cutoff value had pooled specificity of 88.6% (95% CI 85.9-90.9) and pooled sensitivity was found to be 60.4% (95% CI 57.7-62.9). The pooled positive likelihood ratio was 4.5 (95% CI 2.9-6.9) and the pooled negative likelihood ratio was 0.45 (95% CI 0.38-0.52). The pooled diagnostic odds ratio, the odds of having mucinous cyst with elevated CEA, was 11.4 (95% CI 6.9-18.7). The P for chi-squared heterogeneity for all the pooled accuracy estimates was > 0.10.

CONCLUSIONS

This meta-analysis suggests that the cyst fluid CEA level at a 192 ng/mL cutoff value is highly specific in the diagnosis of mucinous cystic lesions with reasonable sensitivity.

Non-inflammatory pancreatic cysts: from diagnosis to treatment (97 cases series)

OBJECTIVE

to describe the implications of the diagnosis and treatment of non-inflammatory pancreatic cysts in a series of patients.

METHODS

we included patients with pancreatic cysts ≥1.0 cm, excluding those with a presumptive diagnosis of a pseudocyst. Imaging tests, echoendoscopy, and histopathology determined the diagnosis of the type of cyst. We applied the guidelines of the International Association of Pancreatology, with some modifications, in patients with mucinous or indeterminate lesions.

RESULTS

97 adult patients participated in the study. A cystic neoplasm of the pancreas was diagnosed in 82.5% of cases. Diagnosis was mainly made by magnetic resonance (46% of cases). The two most common diagnoses were intraductal papillary mucinous neoplasm (43.3%) and serous cystadenoma (26%). Twenty-nine patients underwent surgery (33.3%). The most common surgical procedure was distal pancreatectomy associated with splenectomy in 19 cases (65.5%). Among the operated patients, 11 were diagnosed with cancer. None of the followed, non-operated patients had a diagnosis of cancer.

CONCLUSIONS

magnetic resonance showed good accuracy, particularly in the diagnosis of intraductal papillary mucinous neoplasm. The guidelines of the International Association of Pancreatology, as applied in this study, showed a negative predictive value for cancer of 100%. A development of better diagnostic tests can reduce the number of unnecessary operations.

Pancreaticobiliary endoscopic ultrasound in England 2007 to 2016: Changing practice and outcomes

Background and study aims  Population-level data on the outcomes of pancreaticobiliary endoscopic ultrasound (PB-EUS) are limited. We examined national PB-EUS and fine-needle aspiration (FNA) activity, its relation to pancreatic cancer therapy, associated mortality and adverse events. Patients and methods  Adults undergoing PB-EUS in England from 2007-2016 were identified in Hospital Episode Statistics. A pancreatic cancer cohort diagnosed within 6 months of PB-EUS were studied separately. Multivariable logistic regression models examined associations with 30-day mortality and therapies for pancreatic cancer. Results  79,269 PB-EUS in 68,908 subjects were identified. Annual numbers increased from 2,874 (28 % FNA) to 12,752 (35 % FNA) from 2007 to 2016. 8,840 subjects (13 %) were diagnosed with pancreatic cancer. Sedation related adverse events were coded in 0.5 % and emergency admission with acute pancreatitis in 0.2 % within 48 hours of PB-EUS. 1.5 % of subjects died within 30 days of PB-EUS. Factors associated with 30-day mortality included increasing age (odds ratio 1.03 [95 % CI 1.03-1.04]); male sex (1.38 [1.24-1.56]); increasing comorbidity (1.49 [1.27-1.74]); EUS-FNA (2.26 [1.98-2.57]); pancreatic cancer (1.39 [1.19-1.62]); increasing deprivation (least deprived quintile 0.76 [0.62-0.93]) and lower provider PB-EUS volume (2.83 [2.15-3.73]). Factors associated with surgical resection in the pancreatic cancer cohort included lower provider PB-EUS volume (0.44 [0.26-0.74]) and the least deprived subjects (1.33 [1.12-1.57]). 33 % of pancreatic cancer subjects who underwent EUS, did not subsequently receive active cancer treatment. Conclusions  Lower provider PB-EUS volume was associated with higher 30-day mortality and reduced rates of both pancreatic cancer surgery and chemotherapy. These results suggest potential issues with case selection in lower-volume EUS providers.

Clinical suspicion of pancreatic cancer despite negative endoscopic ultrasound-guided fine-needle aspiration biopsy

BACKGROUND

The early and accurate diagnosis of pancreatic ductal adenocarcinoma is vital for improving the efficacy of therapeutic interventions and to provide patients with the best chance of survival. While endoscopic ultrasound-fine needle aspiration (EUS-FNA) has been demonstrated to be a reliable and accurate diagnostic tool for solid pancreatic neoplasms, the ongoing management of patients with a high clinical suspicion for malignancy but with a negative EUS-FNA biopsy result can prove a challenge.

METHODS

We describe five patients from a single centre who presented for further work-up of a pancreatic mass and/or imaging features concerning for a periampullary malignancy.

RESULTS

All patients had at least one EUS-FNA biopsy performed which returned no malignant cells on cytology. Despite these negative cytology results, all patients underwent further invasive investigation through upfront resection (pancreaticoduodenectomy) or extra-pancreatic biopsy (laparoscopic biopsy of peritoneal nodule) due to worrisome features on imaging, biochemical factors and clinical presentation culminating in a high degree of suspicion for malignancy. The final tissue histopathological diagnosis in all patients was pancreatic ductal adenocarcinoma.

CONCLUSION

This case series highlights the important clinical findings, imaging and biochemical features which need to be considered in patients who have high suspicion for malignancy despite having a negative EUS-FNA cytology result. In these patients with a high index of suspicion, surgical intervention through an upfront resection or further invasive investigation should not be delayed.

Pancreatic cyst fluid glucose in differentiating mucinous from nonmucinous pancreatic cysts: a systematic review and meta-analysis

BACKGROUND AND AIMS

Recently, low levels of intracystic glucose acquired with EUS-guided pancreatic cyst fluid sampling have been shown to help to differentiate mucinous from nonmucinous cystic neoplasms. The aim of this study was to perform a systematic review and meta-analysis to evaluate the diagnostic characteristics of pancreatic cyst fluid glucose compared with carcinoembryonic antigen (CEA) for pancreatic cystic lesions.

METHODS

Individualized searches were developed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-Analysis of Observational Studies in Epidemiology guidelines and meta-analysis analyzed according to Cochrane Diagnostic Test Accuracy working group methodology. A bivariate model was used to compute pooled sensitivity and specificity, likelihood ratio, diagnostic odds ratio, and summary receiver operating characteristics curve for intracystic glucose or CEA alone or combination testing.

RESULTS

Eight studies (609 lesions; mean patient age, 63.56 ± 2.75 years; 60.36% women) were included. The pooled sensitivity for pancreatic cyst fluid glucose was significantly higher compared with CEA alone (91% [95% confidence interval {CI}, 88-94; I² = .00] vs 56% [95% CI, 46-66; I² = 537.14]; P < .001) with no difference in specificity (86% [95% CI, 81-90; I² = 24.16] vs 96% [95% CI, 90-99; I² = 38.06]; P > .05). Diagnostic accuracy was significantly higher for pancreatic cyst fluid glucose versus CEA alone (94% [95% CI, 91-96] vs 85% [95% CI, 82-88]; P < .001). Combination testing with pancreatic cyst fluid glucose and CEA did not improve the diagnostic accuracy compared with glucose alone (97% [95% CI, 95-98] vs 94% [95% CI, 91-96]; P > .05).

CONCLUSIONS

Low pancreatic cyst fluid glucose was associated with a high sensitivity and specificity with significantly improved diagnostic accuracy compared with CEA alone for the diagnosis of mucinous versus nonmucinous pancreatic cystic lesions.

Rapid diagnosis of mucinous cystic pancreatic lesions by on-site cyst fluid glucometry

INTRODUCTION

Available intracystic biomarkers show a limited accuracy for characterizing cystic pancreatic lesions (CPL). Glucose is an attractive alternative due to its availability, low cost and the possibility of on-site quantification by glucometry.

AIM

To evaluate the diagnostic accuracy of on-site glucometry from samples obtained by EUS-FNA in the differential diagnosis between mucinous from non-mucinous CPL.

METHODS

Retrospective, multicentre, cross-sectional study of patients who underwent EUS-FNA of a CPL. A derivation and a validation cohorts were evaluated. Intracystic glucose was quantified by on-site glucometry and colorimetry in the lab. Final diagnosis was based on surgical specimens or global evaluation of clinical and imaging data, cytology and intracystic CEA. Diagnostic accuracy was based on Receiver Operating Curve (ROC) curve analysis. Intraclass correlation coefficient (ICC) between on-site and lab glucose levels was calculated.

RESULTS

Seventy two patients were finally analysed (40 in the derivation cohort and 32 in the validation cohort). Intracystic glucose levels by on-site glucometry was 12.3 ± 28.2 mg/dl for mucinous CPL and 103.3 ± 58.2 mg/dl for non-mucinous CPL, p < 0.001. For an optimal cut-off point of 73 mg/dl, on-site glucose had a sensitivity, specificity, and positive and negative predictive value for the diagnosis of mucinous CPL of 0.89, 0.90, 0.94, 0.82 respectively in the derivation cohort, and 1.0, 0.71, 0.91, 1.0 respectively in the validation cohort. Correlation of on-site and lab glucose quantification was very high (ICC = 0.98).

CONCLUSION

On-site glucometry is a feasible, accurate and reproducible method for the characterization of CPL after EUS-FNA. It shows an excellent correlation with laboratory glucose values. Registration number: 2019/612.

An international study of interobserver variability of "string sign" of pancreatic cysts among experienced endosonographers

Background and Objectives:

No single optimal test reliably determines the pancreatic cyst subtype. Following EUS-FNA, the “string sign” test can differentiate mucinous from nonmucinous cysts. However, the interobserver variability of string sign results has not been studied.

Methods:

An experienced endosonographer performed EUS-FNA of pancreatic cysts on different patients and was recorded on video performing the string sign test for each. The videos were shared internationally with 14 experienced endosonographers, with a survey for each video: “Is the string sign positive?” and “If the string sign is positive, what is the length of the formed string?” Also asked “What is the cutoff length for string sign to be considered positive?” Interobserver variability was assessed using the kappa statistic (κ).

Results:

A total of 112 observations were collected from 14 endosonographers. Regarding string sign test positivity, κ was 0.6 among 14 observers indicating good interrater agreement (P < 0.001) while κ was 0.38 when observers were compared to the index endosonographer demonstrating marginal agreement (P < 0.001). Among observations of the length of the string in positive samples, 89.8% showed >5 mm of variability (P < 0.001), indicating marked variability. There was poor agreement on the cutoff length for a string to be considered positive.

Conclusion:

String sign of pancreatic cysts has a good interobserver agreement regarding its positivity that can help in differentiating mucinous from nonmucinous pancreatic cysts. However, the agreement is poor on the measured length of the string and the cutoff length of the formed string to be considered a positive string sign.

Cyst Fluid Carcinoembryonic Antigen Level Difference between Mucinous Cystic Neoplasms and Intraductal Papillary Mucinous Neoplasms

BACKGROUND/AIMS

The role of cyst fluid carcinoembryonic antigen (CEA) level in differentiating mucinous pancreatic cystic lesions (PCLs) is controversial. We investigated the role of cyst fluid CEA in differentiating low-risk (LR)-intraductal papillary mucinous neoplasms (IPMNs) from high-risk (HR)-IPMNs and LR-mucinous cystic neoplasms (MCNs).

METHODS

This was a retrospective study of 466 patients with PCLs who underwent endoscopic ultrasound-guided fine-needleaspiration over a 7-year period. On histology, low-grade dysplasia and intermediate-grade dysplasia were considered LR, whereas high-grade dysplasia and invasive carcinoma were considered HR.

RESULTS

Data on cyst fluid CEA levels were available for 50/102 mucinous PCLs with definitive diagnoses. The median CEA (range) levels were significantly higher in HR cysts than in LR cysts (2,624 [0.5-266,510] ng/mL vs. 100 [16.8-53,445]ng/mL, p=0.0012). The area under the receiver operating characteristic curve (AUROC) was 0.930 (95% confidence interval [CI], 0.5-0.8; p<0.001) for differentiating LR-IPMNs from LR-MCNs. The AUROC was 0.921 (95% CI, 0.823-1.000; p<0.001) for differentiating LR-IPMNs from HR-IPMNs. Both had a CEA cutoff level of >100ng/mL, with a negative predictive value (NPV) of 100%.

CONCLUSION

Cyst fluid CEA levels significantly vary between LR-IPMNs, LR-MCNs, and HR-IPMNs. A CEA cutoff level of >100ng/mL had a 100% NPV in differentiating LR-IPMNs from LR-MCNs and HR-IPMNs.

Validation of European evidence-based guidelines and American College of Gastroenterology guidelines as predictors of advanced neoplasia in patients with suspected mucinous pancreatic cystic neoplasms

BACKGROUND AND AIM

The European evidence-based guidelines (EEG) and American College of Gastroenterology Guidelines (ACGG) have been published to guide the management of pancreatic cystic lesions. We aim to evaluate the value of both guidelines in predicting advanced pancreatic cystic lesions (A-PCLs) with preoperatively imaging-suspected cystic mucinous pancreatic neoplasms (cMNs).

METHODS

One hundred ninety-eight patients who underwent resections from 2013 to 2019 for suspected cMNs were retrospectively reviewed. Receiver operating characteristic curves were calculated and compared with measure diagnostic value.

RESULTS

Sixty-two patients were diagnosed with A-PCLs pathologically. Cross-imaging modalities had comparable diagnostic accuracy to endoscopic ultrasound in type classification and A-PCLs prediction. Receiver operating characteristic curve comparison analyses showed that EEG absolute + MCN (EEG^AM ) and EEG relative + MCN (EEG^RM ) having at least one indications criteria were comparable to the ACGG (P = 0.21 and P = 0.45). For the criteria having at least two indications, ACGG was superior to EEG^AM (P = 0.001) but comparable to EEG^RM (P = 0.12). EEG^AM ≥ 1 indication criteria was superior to ≥ 2 indications criteria (P = 0.02). EEG^RM ≥ 1 indication criteria had comparable diagnostic performance with ≥ 2 indications criteria (P = 0.86). ACGG ≥ 2 indications criteria was superior to ≥ 1 indication criteria (P = 0.02).

CONCLUSION

On the basis of cross-imaging evaluations, both sets of guidelines were found to be helpful in identifying A-PCLs in suspected cMNs with comparable performance. EEG^AM  ≥ 1 indication criteria was superior to ≥ 2 indications criteria. ACGG ≥ 2 indications criteria was superior to ≥ 1 indication criteria.

Molecular Diagnostics and Testing for Pancreatic Cysts

PURPOSE OF REVIEW

In current clinical practice, the diagnosis and management of pancreatic cystic lesions (PCLs) are based on guidelines that combine clinical and imaging findings. These guidelines usefully identify a large category of low-risk PCLs that do not require treatment. However, they have limited accuracy for diagnosis of advanced neoplasia in worrisome and high-risk PCLs. Novel molecular markers that can accurately detect advanced neoplasia in PCLs can transform the care of patients with PCLs. We reviewed the recent medical literature on molecular diagnostics of PCLs and summarized molecular biomarkers assayed in cyst fluid, pancreatic juice, and blood.

RECENT FINDINGS

Several studies have been recently published describing promising early results in genetic, epigenetic, and protein biomarkers from cyst fluid to help in both histologic diagnosis and detection of advanced neoplasia. The majority of studies have been completed using opportunistically collected archival cyst fluid and few report validation in independent sample sets. Results of ongoing multicenter prospective validation studies are awaited and will help define the best combination of cyst fluid molecular markers. In multifocal PCLs communicating with the pancreatic ductal system, a pancreatic juice biomarker is likely to be less invasive and more informative. Novel biomarkers in pancreatic juice and blood are in early phases of study.

SUMMARY

The field of molecular diagnostic biomarkers for PCLs is rapidly evolving with several promising candidate markers being prospectively evaluated. In the near future, these novel molecular markers, combined with advances in imaging technology, will transform clinical decision-making in the management of PCLs and improve patient outcomes.

Diagnostic yield of endoscopic ultrasound with fine-needle aspiration in pancreatic cystic lesions

INTRODUCTION

Despite advances in imaging techniques, in many cases they are insufficient to establish the diagnosis of pancreatic cystic lesions (PCL). There are few publications in our setting that evaluate the combination of several methods obtained by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). The aim of the study was to evaluate the overall utility of EUS-FNA in the diagnosis of PCL.

MATERIAL AND METHODS

Retrospective study based on a database updated prospectively of a cohort of patients referred for EUS-FNA due to PCL detected in an imaging test. The sensitivity, specificity and diagnostic yield of carcinoembryonic antigen (CEA), cytology and viscosity were studied to detect mucinous lesions.

RESULTS

From November 2013 to April 2018, 122 EUS were performed for PCL. EUS-FNA was performed in 94/122 (77%) and 21/122 (17.2%) patients were operated on. We included 33/122 patients who had diagnostic confirmation by histology, imaging (serous cyst with typical pattern) or clinical evolution. The study of the ROC curve determined the cutoff point ≥419 ng/ml to differentiate mucinous/non-mucinous cystic lesions. The diagnostic yield of CEA was 87.5% (21/24), cytology 81.8% (27/33) and viscosity 84.4% (27/32). The three parameters in combination obtained the best result (30/33, 90.9%).

CONCLUSION

The combination of CEA analysis, cytology and viscosity of pancreatic fluid obtained by EUS-FNA increases the performance in the diagnosis of mucinous pancreatic cystic lesions, with it being greater than 90%.

Glycopatterns and Glycoproteins Changes in MCN and SCN: A Prospective Cohort Study

Background. Advances in imaging improve the detection of malignant pancreatic cystic including mucinous cystic neoplasm (MCN), intraductal papillary mucinous neoplasm (IPMN), and mucinous cystic adenocarcinoma (MCA), but the distinction between benign and malignant lesions remains a problem. In an effort to establish glycopatterns as potential biomarkers for differential diagnosis between MCN and SCN, we systematically investigated the alterations of glycopatterns in cystic fluids for both SCN and MCN. Methods. Among the 75 patients enrolled, 37 were diagnosed as MCN and 38 as SCN based on histology. Lectin microarray analysis was performed on each sample, and the fluorescence intensity was used to obtain the fold-change. Then, mixed cyst fluids of MCN group and SCN group were cross bonded with magnetic particles coupled by Lectin STL and WGA, respectively. Hydrophilic interaction liquid chromatography (HILIC) enrichment was performed, liquid chromatography (LC)/mass spectrometry (MS) analysis and bioinformatical analysis was conducted to find the differential glycoproteins between MCNs and SCNs. Results. Through analysis of lectin microarray between MCNs and SCNs, stronger lectin signal patterns were assigned to Lectin WFA, DBA, STL, WGA, and BPL; and weaker signal patterns were assigned to Lectin PTL-I, Con A, ACA, and MAL-I. The glycoproteins were enriched by STL or WGA-coupled magnetic particles. Furthermore, the 10 identified correspondding genes were found to be significantly elevated in the mucinous cystadenoma: CLU, A2M, FGA, FGB, FGG, PLG, SERPINA1, SERPING1, C5, C8A, and C9. Bioinformatics analysis revealed that the above genes may activate the KEGG pathway: immune complement system. Conclusion. This study shows changes in glycopatterns and glycoproteins are associated with MCNs and SCNs.

Diagnosis and management of pancreatic cystic neoplasms

This review outlines the current classification of pancreatic cystic lesions, with a particular emphasis on pancreatic cystic neoplasms (PCNs). It will describe the diagnostic approach to PCNs, with reference to clinicopathological features, cross-sectional radiology and endoscopic ultrasound. This review will conclude with an evidence-based discussion of the management of PCNs focused on recent clinical guidelines.

An international, multi-institution survey of the use of EUS in the diagnosis of pancreatic cystic lesions

Background and Objectives:

Currently, pancreatic cystic lesions (PCLs) are recognized with increasing frequency and have become a more common finding in clinical practice. EUS is challenging in the diagnosis of PCLs and evidence-based decisions are lacking in its application. This study aimed to develop strong recommendations for the use of EUS in the diagnosis of PCLs, based on the experience of experts in the field.

Methods:

A survey regarding the practice of EUS in the evaluation of PCLs was drafted by the committee member of the International Society of EUS Task Force (ISEUS-TF). It was disseminated to experts of EUS who were also members of the ISEUS-TF. In some cases, percentage agreement with some statements was calculated; in others, the options with the greatest numbers of responses were summarized.

Results:

Fifteen questions were extracted and disseminated among 60 experts for the survey. Fifty-three experts completed the survey within the specified time frame. The average volume of EUS cases at the experts' institutions is 988.5 cases per year.

Conclusion:

Despite the limitations of EUS alone in the morphologic diagnosis of PCLs, the results of the survey indicate that EUS-guided fine-needle aspiration is widely expected to become a more valuable method.

Diagnosis of intraductal papillary mucinous neoplasm using endoscopic ultrasound guided microbiopsies: A case report

Pancreatic cysts are increasingly diagnosed due to expanding use of cross-sectional imaging, but current diagnostic modalities have limited diagnostic accuracy. Recently, a novel through-the-needle microbiopsy forceps has become available, offering the possibility of obtaining cyst-wall biopsies. We present a case of 41-year-old male with chronic pancreatitis and a 2-cm pancreatic cyst, initially considered a pseudocyst. Subsequently, endoscopic ultrasound guided microbiopsies were successfully obtained, which surprisingly revealed an intraductal papillary mucinous neoplasm of mixed subtype with low grade dysplasia. In conclusion, obtaining biopsies from the wall of the pancreatic cystic lesions with this novel instrument is feasible and, as demonstrated in this case, can possibly alter the clinical outcome. Microbiopsies offered enough cellular material, allowing supplemental gene mutation analysis, which combined with other modalities could lead to a more individual approach when treating pancreatic cysts. However, prospective studies are warranted before routine clinical implementation.

Pancreatic cyst fluid glucose: rapid, inexpensive, and accurate diagnosis of mucinous pancreatic cysts

BACKGROUND

The most widely accepted biochemical test for preoperative differentiation of mucinous from benign, nonmucinous pancreatic cysts is cyst fluid carcinoembryonic antigen. However, the diagnostic accuracy of carcinoembryonic antigen ranges from 70% to 86%. Based on previous work, we hypothesize that pancreatic cyst fluid glucose may be an attractive alternative to carcinoembryonic antigen.

METHODS

Pancreatic cyst fluid was collected during endoscopic or operative intervention. Diagnoses were pathologically confirmed. Glucose and carcinoembryonic antigen were measured using a patient glucometer and automated analyzer/enzyme-linked immunosorbent assay. Sensitivity, specificity, accuracy, and receiver operator characteristic analyses were performed.

RESULTS

Cyst fluid samples from 153 patients were evaluated (mucinous: 25 mucinous cystic neoplasms, 77 intraductal papillary mucinous neoplasms, 4 ductal adenocarcinomas; nonmucinous: 21 serous cystic neoplasms, 9 cystic neuroendocrine tumors, 14 pseudocysts, 3 solid pseudopapillary neoplasms). Median cyst fluid glucose was lower in mucinous versus nonmucinous cysts (19 vs 96 mg/dL; P < .0001). With a threshold of ≤ 50 mg/dL, cyst fluid glucose was 92% sensitive, 87% specific, and 90% accurate in diagnosing mucinous pancreatic cysts. In comparison, cyst fluid carcinoembryonic antigen with a threshold of >192 ng/mL was 58% sensitive, 96% specific, and 69% accurate. Area under the curve for glucose and CEA were similar at 0.91 and 0.92.

CONCLUSION

Cyst fluid glucose has significant advantages over carcinoembryonic antigen and should be considered for use as a routine diagnostic test for pancreatic mucinous cysts.

Proteome characterization of human pancreatic cyst fluid from intraductal papillary mucinous neoplasm by liquid chromatography/tandem mass spectrometry

RATIONALE

In recent years, the molecular components of pancreatic cyst fluid have been used for diagnosis and prognosis. Because the protein markers that are currently used in clinical tests are unreliable, proteomic studies to find new protein markers are being conducted. However, such researches have been limited due to the complexity of pancreatic cyst fluid and the immaturity of proteomic techniques.

METHODS

To overcome these limitations and provide a pancreatic cyst proteome dataset, we examined cyst fluid proteome with tandem mass spectrometry. The proteomic analysis was performed using a Orbitrap-based mass spectrometer (Q-Exactive) coupled with a 50-cm-long nano-liquid chromatography column. Protein mutations were identified using mutation sequence database search.

RESULTS

A total of 5850 protein groups were identified from microliters of cyst fluid. Among those, 3934 protein groups were reported for the first time in pancreatic cyst fluid. Although high-abundance proteins were not depleted in the experiment, our dataset detected almost all pancreatic tumor markers such as mucin family members, S100 proteins, and CEA-related proteins. In addition, 590 protein mutation marker candidates were discovered.

CONCLUSIONS

We provide a comprehensive cyst proteome dataset that includes cystic cellular proteins and mutated proteins. Our findings would serve as a rich resource for further IPMN studies and clinical applications. The MS data have been deposited in the ProteomeXchange with identifier PXD005671 (http://proteomecentral.proteomexchange.org/dataset/PXD005671).

Computer-assisted cytologic diagnosis in pancreatic FNA: An application of neural networks to image analysis

BACKGROUND

Fine-needle aspiration (FNA) biopsy is an accurate method for the diagnosis of solid pancreatic masses. However, a significant number of cases still pose a diagnostic challenge. The authors have attempted to design a computer model to aid in the diagnosis of these biopsies.

METHODS

Images were captured of cell clusters on ThinPrep slides from 75 pancreatic FNA cases (20 malignant, 24 benign, and 31 atypical). A K-means clustering algorithm was used to segment the cell clusters into separable regions of interest before extracting features similar to those used for cytomorphologic assessment. A multilayer perceptron neural network (MNN) was trained and then tested for its ability to distinguish benign from malignant cases.

RESULTS

A total of 277 images of cell clusters were obtained. K-means clustering identified 68,301 possible regions of interest overall. Features such as contour, perimeter, and area were found to be significantly different between malignant and benign images (P <.05). The MNN was 100% accurate for benign and malignant categories. The model's predictions from the atypical data set were 77% accurate.

CONCLUSIONS

The results of the current study demonstrate that computer models can be used successfully to distinguish benign from malignant pancreatic cytology. The fact that the model can categorize atypical cases into benign or malignant with 77% accuracy highlights the great potential of this technology. Although further study is warranted to validate its clinical applications in pancreatic and perhaps other areas of cytology as well, the potential for improved patient outcomes using MNN for image analysis in pathology is significant. Cancer Cytopathol 2017;125:926-33. © 2017 American Cancer Society.

Cystic fluid neutrophil gelatinase-associated lipocalin (NGAL) concentration in differential diagnosis of pancreatic cystic lesions: a new factor enters the scene?

Introduction

Neutrophil gelatinase-associated lipocalin – 25 kDa peptide – is at present one of the most fascinating and unrecognised proteins implicated in the process of tumour development. Precise assessment of pancreatic cystic lesions is crucial for selecting available treatment options, such as conservative therapy or surgical resection.

Aim

To determine the utility of NGAL concentration in cyst fluid obtained by endoscopic ultrasound (EUS) with EUS-guided fine-needle aspiration (EUS-FNA) to distinguish neoplastic pancreatic cysts from pseudocysts.

Material and methods

Twenty-two patients underwent EUS and FNA of a pancreatic cystic lesion; 9 of these patients underwent surgical resection, providing a histologic diagnosis of the cystic lesion. Furthermore, the final diagnosis was based on cyst fluid cytology, cyst fluid tumour markers (CEA, CA 72-4, CA 19-9), and medical history. Patients were divided in two groups: cystic neoplasms and inflammatory cysts (pseudocysts).

Results

The final diagnosis was pseudocyst in 7 patients, serous cystadenoma in 4, mucinous cystadenoma in 3, intraductal papillary mucinous neoplasms in 6 patients, and cystic form of pancreatic adenocarcinoma in 2. Cyst fluid analysis of these patients showed that median cyst fluid NGAL for the cystic neoplasm group (211 ng/ml; n = 15) was significantly lower (p = 0.02) than the inflammatory cystic group (4689 ng/ml; n = 7). Correlation analysis showed that only fluid CA 72-4 was positively related to NGAL (r = 0.8, p < 0.01).

Conclusions

In this single-centre study, pancreatic cyst fluid NGAL concentration appeared to be useful in distinguishing neoplastic pancreatic cysts from pseudocysts. Larger studies are recommended to evaluate this role further.

Imaging modalities for characterising focal pancreatic lesions

BACKGROUND

Increasing numbers of incidental pancreatic lesions are being detected each year. Accurate characterisation of pancreatic lesions into benign, precancerous, and cancer masses is crucial in deciding whether to use treatment or surveillance. Distinguishing benign lesions from precancerous and cancerous lesions can prevent patients from undergoing unnecessary major surgery. Despite the importance of accurately classifying pancreatic lesions, there is no clear algorithm for management of focal pancreatic lesions.

OBJECTIVES

To determine and compare the diagnostic accuracy of various imaging modalities in detecting cancerous and precancerous lesions in people with focal pancreatic lesions.

SEARCH METHODS

We searched the CENTRAL, MEDLINE, Embase, and Science Citation Index until 19 July 2016. We searched the references of included studies to identify further studies. We did not restrict studies based on language or publication status, or whether data were collected prospectively or retrospectively.

SELECTION CRITERIA

We planned to include studies reporting cross-sectional information on the index test (CT (computed tomography), MRI (magnetic resonance imaging), PET (positron emission tomography), EUS (endoscopic ultrasound), EUS elastography, and EUS-guided biopsy or FNA (fine-needle aspiration)) and reference standard (confirmation of the nature of the lesion was obtained by histopathological examination of the entire lesion by surgical excision, or histopathological examination for confirmation of precancer or cancer by biopsy and clinical follow-up of at least six months in people with negative index tests) in people with pancreatic lesions irrespective of language or publication status or whether the data were collected prospectively or retrospectively.

DATA COLLECTION AND ANALYSIS

Two review authors independently searched the references to identify relevant studies and extracted the data. We planned to use the bivariate analysis to calculate the summary sensitivity and specificity with their 95% confidence intervals and the hierarchical summary receiver operating characteristic (HSROC) to compare the tests and assess heterogeneity, but used simpler models (such as univariate random-effects model and univariate fixed-effect model) for combining studies when appropriate because of the sparse data. We were unable to compare the diagnostic performance of the tests using formal statistical methods because of sparse data.

MAIN RESULTS

We included 54 studies involving a total of 3,196 participants evaluating the diagnostic accuracy of various index tests. In these 54 studies, eight different target conditions were identified with different final diagnoses constituting benign, precancerous, and cancerous lesions. None of the studies was of high methodological quality. None of the comparisons in which single studies were included was of sufficiently high methodological quality to warrant highlighting of the results. For differentiation of cancerous lesions from benign or precancerous lesions, we identified only one study per index test. The second analysis, of studies differentiating cancerous versus benign lesions, provided three tests in which meta-analysis could be performed. The sensitivities and specificities for diagnosing cancer were: EUS-FNA: sensitivity 0.79 (95% confidence interval (CI) 0.07 to 1.00), specificity 1.00 (95% CI 0.91 to 1.00); EUS: sensitivity 0.95 (95% CI 0.84 to 0.99), specificity 0.53 (95% CI 0.31 to 0.74); PET: sensitivity 0.92 (95% CI 0.80 to 0.97), specificity 0.65 (95% CI 0.39 to 0.84). The third analysis, of studies differentiating precancerous or cancerous lesions from benign lesions, only provided one test (EUS-FNA) in which meta-analysis was performed. EUS-FNA had moderate sensitivity for diagnosing precancerous or cancerous lesions (sensitivity 0.73 (95% CI 0.01 to 1.00) and high specificity 0.94 (95% CI 0.15 to 1.00), the extremely wide confidence intervals reflecting the heterogeneity between the studies). The fourth analysis, of studies differentiating cancerous (invasive carcinoma) from precancerous (dysplasia) provided three tests in which meta-analysis was performed. The sensitivities and specificities for diagnosing invasive carcinoma were: CT: sensitivity 0.72 (95% CI 0.50 to 0.87), specificity 0.92 (95% CI 0.81 to 0.97); EUS: sensitivity 0.78 (95% CI 0.44 to 0.94), specificity 0.91 (95% CI 0.61 to 0.98); EUS-FNA: sensitivity 0.66 (95% CI 0.03 to 0.99), specificity 0.92 (95% CI 0.73 to 0.98). The fifth analysis, of studies differentiating cancerous (high-grade dysplasia or invasive carcinoma) versus precancerous (low- or intermediate-grade dysplasia) provided six tests in which meta-analysis was performed. The sensitivities and specificities for diagnosing cancer (high-grade dysplasia or invasive carcinoma) were: CT: sensitivity 0.87 (95% CI 0.00 to 1.00), specificity 0.96 (95% CI 0.00 to 1.00); EUS: sensitivity 0.86 (95% CI 0.74 to 0.92), specificity 0.91 (95% CI 0.83 to 0.96); EUS-FNA: sensitivity 0.47 (95% CI 0.24 to 0.70), specificity 0.91 (95% CI 0.32 to 1.00); EUS-FNA carcinoembryonic antigen 200 ng/mL: sensitivity 0.58 (95% CI 0.28 to 0.83), specificity 0.51 (95% CI 0.19 to 0.81); MRI: sensitivity 0.69 (95% CI 0.44 to 0.86), specificity 0.93 (95% CI 0.43 to 1.00); PET: sensitivity 0.90 (95% CI 0.79 to 0.96), specificity 0.94 (95% CI 0.81 to 0.99). The sixth analysis, of studies differentiating cancerous (invasive carcinoma) from precancerous (low-grade dysplasia) provided no tests in which meta-analysis was performed. The seventh analysis, of studies differentiating precancerous or cancerous (intermediate- or high-grade dysplasia or invasive carcinoma) from precancerous (low-grade dysplasia) provided two tests in which meta-analysis was performed. The sensitivity and specificity for diagnosing cancer were: CT: sensitivity 0.83 (95% CI 0.68 to 0.92), specificity 0.83 (95% CI 0.64 to 0.93) and MRI: sensitivity 0.80 (95% CI 0.58 to 0.92), specificity 0.81 (95% CI 0.53 to 0.95), respectively. The eighth analysis, of studies differentiating precancerous or cancerous (intermediate- or high-grade dysplasia or invasive carcinoma) from precancerous (low-grade dysplasia) or benign lesions provided no test in which meta-analysis was performed.There were no major alterations in the subgroup analysis of cystic pancreatic focal lesions (42 studies; 2086 participants). None of the included studies evaluated EUS elastography or sequential testing.

AUTHORS' CONCLUSIONS

We were unable to arrive at any firm conclusions because of the differences in the way that study authors classified focal pancreatic lesions into cancerous, precancerous, and benign lesions; the inclusion of few studies with wide confidence intervals for each comparison; poor methodological quality in the studies; and heterogeneity in the estimates within comparisons.

Differentiation of Pancreatic Cyst Types by Analysis of Rheological Behavior of Pancreatic Cyst Fluid

Differentiation between mucinous and non-mucinous pancreatic cysts is exceedingly important and challenging, particularly as the former bears malignant transformation potential. Pancreatic cyst fluid (PCF)-based diagnostics, including analyses of biochemical markers, as well as cytology, has shown inadequate accuracy. Herein, a preliminary single-center study of 22 PCF samples, collected by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA), assessed the rheological behavior of PCF and its correlation with lesion type. The dependence of PCF shear viscosity on shear rate was found to follow a power law and could be fitted using Ostwald-de Waele model. Three types of flow curves were identified, where two types correlated with non-mucinous cysts, differing by their power law exponent, and the third type corresponding to mucinous cysts. Viscosity measured at a high shear rate was shown to serve as an accurate and independent marker distinguishing between mucinous and non-mucinous cysts, with an optimal cutoff value of ηc = 1.3 cP The accuracy of this novel technique proved superior to string-sign, cytology, carcinoembryonic antigen, and amylase assessments. Moreover, the combined predictive value of ηc and patient age provided for sensitivity and specificity of 100% and 95.5%, respectively. This simple and rapid diagnostic tool can be immediately implemented after EUS-FNA sampling.

The Evolving Role of Pathology in New Developments, Classification, Terminology, and Diagnosis of Pancreatobiliary Neoplasms

Pancreatobiliary tract lesions are increasingly being discovered because of more sensitive imaging modalities. Magnetic resonance imaging has identified incidental pancreatic cysts in 13.5% of patients of progressively increasing age. Pancreatobiliary tissue is more accessible through endoscopic ultrasound and magnetic resonance imaging-guided biopsy procedures, and is now an integral part of pathologists' routine practice. Accordingly, several new tumor categories have been recently recognized, including intraductal tubulopapillary neoplasm, a new addition to tumoral intraepithelial neoplasms. Other entities have been reclassified, including the recent transition to 2-tiered grading of preinvasive neoplasms, as well as new perspectives on the distinctive biologic behavior of oncocytic intraductal papillary mucinous neoplasms (IPMNs) compared with other IPMN subtypes. This has led to proposals for revised staging of virtually every segment of the pancreatobiliary tree, with theranostic markers becoming an integral part of workup. Ki-67 is now an integral part of the classification of neuroendocrine tumors, with new definitions of "high-grade neuroendocrine carcinoma." Although bile duct brushings have opened new avenues for diagnosis, their sensitivity remains low and often requires concomitant fluorescent in situ hybridization to better define ambiguous cases. Various molecular pathways have been elucidated for pancreatic cysts, including KRAS for ductal neoplasia, GNAS for intestinal IPMNs, RNF3 for mucinous cysts, and VHL for serous cystic neoplasms, all key players in diagnostic workup. Integration of these updates into our understanding of pancreatobiliary disease requires active engagement of pathologists for appropriate specimen triage, judicious interpretation of results, and incorporation into reporting and staging. They also provide exciting opportunities for targeted therapy.

Pancreatic Cytopathology

Pancreatic cytopathology, particularly through the use of endoscopic ultrasound-guided fine-needle aspiration (FNA), has excellent specificity and sensitivity for the diagnosis of pancreatic lesions. Such diagnoses can help guide preoperative management of patients, provide prognostic information, and confirm diagnoses in patients who are not surgical candidates. Furthermore, FNA can be used to obtain cyst fluid for ancillary tests that can improve the diagnosis of cystic lesions. In this article, we describe the cytomorphological features and differential diagnoses of the most commonly encountered pancreatic lesions on FNA.

Role of serial EUS-guided FNA on pancreatic cystic neoplasms: a retrospective analysis of repeat carcinoembryonic antigen measurements

BACKGROUND AND AIMS

Pancreatic cystic neoplasms (PCNs) often need interval surveillance, including repeat EUS, but the role of repeat FNA with fluid analysis is poorly defined. The aim of this analysis is to evaluate the potential clinical significance of serial carcinoembryonic antigen (CEA) measurements by EUS-guided FNA (EUS-FNA) in the surveillance for PCNs.

PATIENTS

Patients who underwent EUS-FNA for PCNs were studied retrospectively. EUS-FNA findings were compared between index and prior procedures among patients who underwent repeat EUS-FNA.

RESULTS

A total of 400 patients with PCNs underwent EUS-FNA. Eighty-seven of those patients had prior EUS-FNA with cyst fluid analysis. Patients with repeat FNA were significantly more likely to have multiple cysts (57% vs 41%; P = .008), multilocular cysts (75% vs 62%; P = .042), connection to pancreatic duct (33% vs 18%; P = .005), and higher initial CEA levels (94.8 vs 25.6 ng/mL; P = .003) compared with patients who had only a single FNA. A comparison of prior and index FNAs did not show significant differences in EUS or cyst fluid analysis findings. After log transformation, the association between CEA level at prior and index FNA was moderate (R² = 0.626; P < .001), but cystic fluid CEA classification with a cutoff value of 192 ng/mL changed in 17 patients (20%), without significant changes in EUS findings.

CONCLUSIONS

Repeat surveillance EUS-FNA resulted in stable CEA levels in the majority of patients, with spurious fluctuations of CEA in approximately 20% of patients. These data call into question any clinical significance attributed to an isolated interval rise in CEA level, especially in light of a stable EUS examination.