Performance of endosonography-guided fine needle aspiration and biopsy in the diagnosis of pancreatic cystic lesions

Current status of endoscopic ultrasound in the diagnosis of intraductal papillary mucinous neoplasms

The new Kyoto guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) provide evidence-based recommendations for the diagnosis and treatment of IPMN. Endoscopic ultrasonography (EUS) is a diagnostic modality with a high spatial resolution that allows detailed observation and obtaining cyst fluid or tissue samples via EUS-guided fine needle aspiration (EUS-FNA). Currently, EUS is an indispensable examination method for the diagnosis of pancreatic diseases. On the other hand, there have been concerns that EUS imaging tends to be highly operator-dependent, and may lack objectivity. Previous guidelines have assigned EUS as an option for patients with worrisome features. However, recent reports indicate that the sensitivity of EUS for the diagnosis of mural nodules (MNs) is more than 90%, comparable or superior to that of contrast-enhanced computed tomography or magnetic resonance cholangiopancreatography. The specific advantages of EUS in the diagnosis of IPMN are: (1) high spatial resolution imaging for the diagnosis of MNs, (2) contrast-enhanced EUS for differentiation of intra-cystic MNs from mucous clots, and (3) pathological diagnosis using EUS-FNA and differential diagnosis of a pancreatic cystic tumor by cystic fluid analysis. In order to utilize EUS in the diagnosis of IPMN, endoscopists are required to have the skills to provide sufficiently objective imaging findings.

Optimization of Endoscopic Ultrasound Characteristics in the Diagnosis of Malignant Intraductal Papillary Mucinous Neoplasm

OBJECTIVES

Endoscopic ultrasound (EUS) is an excellent diagnostic tool that provides high-resolution images of pancreatic cystic lesions. However, its role in the diagnosis of malignant intraductal papillary mucinous neoplasm (IPMN) remains limited and unclear. We aimed to determine the usefulness of this modality for such diagnosis.

METHODS

Overall, 246 patients who underwent EUS for IPMN after computed tomography (CT)/magnetic resonance imaging (MRI) from April 2018 to June 2021 were followed up until March 2022. We assessed the added value of performing EUS after CT or MRI for diagnosing malignant IPMN, using receiver operating characteristic curve analysis. Walls as thick as 2 mm were considered thickened in this study if they were highly uneven.

RESULTS

EUS clearly enhanced accuracy in identifying enhancing nodules and thickened walls. The areas under the receiver operating characteristic curve and corresponding 95% confidence intervals were 0.655 (0.549-0.760) and 0.566 (0.478-0.654) upon CT/MRI but 0.853 (0.763-0.942) and 0.725 (0.634-0.817) when observed using EUS. The combination of nodule size, thickened wall, and main duct size yielded the highest area under the receiver operating characteristic curve (0.944 [0.915-0.973]).

CONCLUSIONS

EUS more accurately detects malignant IPMN, as uneven wall thickening and certain nodules cannot be identified with CT/MRI.

Dilated common bile duct is commonly associated with main duct Intraductal Papillary Mucinous Neoplasm of the pancreas

BACKGROUND

Dilatation of common bile duct (CBD) is mostly pathological and mainly occurs secondary to mechanical causes. We aimed to explore the prevalence of CBD dilatation in Intraductal Papillary Mucinous Neoplasms of the pancreas (IPMN) among patients referred to EUS.

METHODS

A retrospective study of all patients who had an EUS diagnosis of IPMN from 2011 to 2019 at Galilee Medical Center were extracted. Control group including patients with other types of pancreatic cysts.

RESULTS

Overall, 2400 patients were included in the study, of them 158 patients were diagnosed with pancreatic cysts, 117 patients (74%) diagnosed with IPMN (group A), and 41 patients (26%) diagnosed with other pancreatic cysts (group B). Univariate analysis showed significant association of IPMN (OR 3.8, 95% CI 1.3-11.5), resected gallbladder (GB) (OR 7.75, 95% CI 3.19-18.84), and age (OR 1, 95% CI 1.01-1.08) with CBD dilatation. Classifying IPMN to sub-groups using adjusted multivariate logistic regression analysis, only main duct-IPMN (MD-IPMN) significantly correlated with CBD dilatation compared to branch duct (BD)-IPMN and mixed type-IPMN (OR 19.6, 95% CI 4.57-83.33, OR 16.3, 95% CI 3.02-88.08).

CONCLUSION

MD-IPMN was significantly correlated with dilated CBD. Assessment of the pancreas is warranted in encountered cases of dilated CBD without obvious mechanical cause.

Endoscopic Imaging of Pancreatic Cysts

Pancreatic cystic lesions (PCLs) have been diagnosed with increasing frequency likely due to the widespread use of cross-sectional imaging. A precise diagnosis of the PCL is important because it helps identify patients in need of surgical resection and those who can undergo surveillance imaging. A combination of clinical and imaging findings as well as cyst fluid markers can help classify PCLs and guide management. This review focuses on endoscopic imaging of PCLs including endoscopic and endosonographic features and fine needle aspiration. We then review the role of adjunct techniques, such as microforceps, contrast-enhanced endoscopic ultrasound, pancreatoscopy, and confocal laser endomicroscopy.

Usefulness of Contrast-Enhanced Harmonic Endoscopic Ultrasonography for Diagnosis of Malignancy in Intraductal Papillary Mucinous Neoplasm

Intraductal papillary mucinous neoplasms (IPMNs) have a wide pathologic spectrum and it can be difficult to diagnose malignancy, including pathological grade. The aim of this study was to evaluate contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for the diagnosis of malignant IPMN and IPMN-associated invasive carcinoma (invasive IPMC). From 5009 patients diagnosed with IPMN at Wakayama medical university between December 2009 and December 2021, 115 patients who underwent contrast-enhanced computed tomography (CE-CT), conventional EUS, CH-EUS, and surgical resection were enrolled. The detection of mural lesions was compared with pathological findings. Malignant IPMN and invasive IPMC were also assessed according to mural lesion size and vascularity on CH-EUS. CH-EUS and conventional EUS showed significantly higher accuracy than CE-CT in the detection of mural nodules (92%, 83%, and 72%, respectively) and diagnosis of malignant IPMN (75%, 73%, and 63%, respectively). An early wash-out pattern on CH-EUS was observed in significantly more patients with invasive IPMC than in those with low-, intermediate-, or high-grade dysplasia. When compared with CE-CT, CH-EUS was significantly more accurate for detecting mural nodules and more useful for diagnosing malignant IPMN. The vascular pattern on CH-EUS was also useful for diagnosing invasive IPMC.

Quantitative MRI of Pancreatic Cystic Lesions: A New Diagnostic Approach

The commonly used magnetic resonance (MRI) criteria can be insufficient for discriminating mucinous from non-mucinous pancreatic cystic lesions (PCLs). The histological differences between PCLs’ fluid composition may be reflected in MRI images, but cannot be assessed by visual evaluation alone. We investigate whether additional MRI quantitative parameters such as signal intensity measurements (SIMs) and radiomics texture analysis (TA) can aid the differentiation between mucinous and non-mucinous PCLs. Fifty-nine PCLs (mucinous, n = 24; non-mucinous, n = 35) are retrospectively included. The SIMs were performed by two radiologists on T2 and diffusion-weighted images (T2WI and DWI) and apparent diffusion coefficient (ADC) maps. A total of 550 radiomic features were extracted from the T2WI and ADC maps of every lesion. The SIMs and TA features were compared between entities using univariate, receiver-operating, and multivariate analysis. The SIM analysis showed no statistically significant differences between the two groups (p = 0.69, 0.21–0.43, and 0.98 for T2, DWI, and ADC, respectively). Mucinous and non-mucinous PLCs were successfully discriminated by both T2-based (83.2–100% sensitivity and 69.3–96.2% specificity) and ADC-based (40–85% sensitivity and 60–96.67% specificity) radiomic features. SIMs cannot reliably discriminate between PCLs. Radiomics have the potential to augment the common MRI diagnosis of PLCs by providing quantitative and reproducible imaging features, but validation is required by further studies.

Intracystic Glucose and Carcinoembryonic Antigen in Differentiating Histologically Confirmed Pancreatic Mucinous Neoplastic Cysts

INTRODUCTION

Differentiating mucinous neoplastic pancreatic cysts (MNPC) from cysts without malignant potential can be challenging. Guidelines recommend using fluid carcinoembryonic antigen (CEA) to differentiate MNPC; however, its sensitivity and specificity vary widely. Intracystic glucose concentration has shown promise in differentiating MNPC, but data are limited to frozen specimens and cohorts of patients without histologic diagnoses. This study aimed to compare glucose and CEA concentrations in differentiating MNPC using fresh fluid obtained from cysts with confirmatory histologic diagnoses.

METHODS

This multicenter cohort study consisted of patients undergoing endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for pancreatic cysts during January 2013-May 2020. Patients were included if the cyst exhibited a histologic diagnosis and if both CEA and glucose were analyzed from fresh fluid. Receiver operating curve (ROC) characteristics were analyzed, and various diagnostic parameters were compared.

RESULTS

Ninety-three patients, of whom 59 presented with MNPC, met the eligibility criteria. The area under the receiver operating curve (AUROC) was 0.96 for glucose and 0.81 for CEA (difference 0.145, P = 0.003). A CEA concentration of ≥192 ng/mL had sensitivity of 62.7% and specificity of 88.2% in differentiating MNPC, whereas glucose concentration of ≤25 mg/dL had sensitivity and specificity of 88.1% and 91.2%, respectively.

DISCUSSION

Intracystic glucose is superior to CEA concentration for differentiating MNPC when analyzed from freshly obtained fluid of cysts with histologic diagnoses. The advantage of glucose is augmented by its low cost and ease of implementation, and therefore, its widespread adoption should come without barriers. Glucose has supplanted CEA as the best fluid biomarker in differentiating MNPC.

The Role of Interleukin 1 Beta in Differentiating Malignant from Benign Pancreatic Cysts

Background and Aim: The frequency of detection of pancreatic cystic lesions (PCLs) in magnetic resonance imaging performed for reasons unrelated to the pancreas reaches up to 13.5%. The aim of this study was to evaluate the role of cyst fluid interleukin 1 beta (IL1β) and different endoscopic ultrasound (EUS) features in differentiating premalignant/malignant from benign pancreatic cysts. In addition, to evaluate the role of pancreatic cyst fluid carcinoembryonic antigen (CEA) in differentiating mucinous from nonmucinous pancreatic cysts. Methods: This study was conducted on 73 patients with PCLs. EUS-guided fine-needle aspiration (EUS-FNA) was performed on all patients. Estimation of IL1β and CEA levels in aspirated specimens were carried out. Results: Pancreatic cyst fluid IL1β level could not differentiate between premalignant/malignant and benign pancreatic cysts. At a cutoff value of 19.81 ng/mL pancreatic cyst fluid CEA has 64.3% sensitivity and 84.4% specificity in differentiating mucinous from nonmucinous pancreatic cyst. EUS can differentiate between premalignant/malignant pancreatic cysts and benign cysts with a sensitivity of 66.7%, specificity of 69.2% Conclusions: Pancreatic cyst fluid IL1β level cannot differentiate between premalignant/malignant and benign pancreatic cysts. CEA level can help in differentiation between mucinous and nonmucinous cysts. EUS can be useful in differentiation between premalignant/malignant pancreatic cysts and benign cysts.

Co-analysis of pancreatic cyst fluid carcinoembryonic antigen and glucose with novel cut-off levels better distinguishes between mucinous and non-mucinous neoplastic pancreatic cystic lesions

BACKGROUND

Pancreatic cyst fluid analysis plays an important role in distinguishing between mucinous and non-mucinous cyst lesions. We aimed to compare the diagnostic performances of cyst fluid carcinoembryonic antigen (CEA), CA 19-9, and glucose in differentiating mucinous from non-mucinous neoplastic pancreatic cystic lesions (PCLs) and determine the best cut-off levels.

METHODS

Patients' data were evaluated retrospectively. 102 patients' PCLs were grouped as non-neoplastic (n = 25), non-mucinous neoplastic (n = 20), mucinous neoplastic (n = 47) and pancreatic adenocarcinomas with cystic degeneration (n = 10); and CEA, CA 19-9, and glucose levels were compared. Receiver-operating characteristic analysis was performed, and the ideal cut-off values were determined.

RESULTS

Cyst fluid CEA and CA 19-9, levels were significantly higher (P < 0.001, P < 0.001, respectively) and glucose levels were significantly lower (P = 0.001) in mucinous than in non-mucinous neoplastic PCLs. Area under curve with 95% confidence interval of CEA, glucose and CEA and glucose test combination was 0.939 (95% CI = 0.885-0.993, P = 0.001), 0.809 (95% CI = 0.695-0.924, P < 0.001) and 0.937 (95% CI = 0.879-0.995), respectively. CEA cut-offs to rule-in and rule-out mucinous neoplastic were 135.1 ng/mL (sensitivity = 62%, specificity = 94.7%) and 6.12 ng/mL (sensitivity = 94.1%, specificity = 80.4%), respectively. Glucose cut-off of 2.8 mmol/L was chosen both to rule-in and rule-out mucinous neoplastic PCLs (sensitivity = 78%, specificity = 80%). Co-analysis of CEA and glucose to distinguish mucinous from non-mucinous neoplastic PCLs had sensitivity = 87.8%, specificity = 93.3%, and diagnostic accuracy = 89.3%.

CONCLUSIONS

We concluded that co-analysis of cyst fluid CEA (cut-off = 135.1 ng/mL) and glucose (cut-off = 2.8 mmol/L) at novel cut-offs had the best testing performance to rule-in mucinous neoplastic PCLs. To rule-out mucinous PCLs co-analysis of CEA (cut-off = 6.12 ng/mL) and glucose (cut-off = 2.8 mmol/L) added value to prediction.

Comparative analysis of glucose and carcinoembryonic antigen in the diagnosis of pancreatic mucinous cysts: a systematic review and meta-analysis

BACKGROUND AND AIMS

Pancreatic cystic fluid (PCF) analysis is useful to distinguish between different cyst types and to guide management. The aim of our study was to compare the diagnostic accuracy of glucose level with carcinoembryonic antigen (CEA) in PCF for mucinous cyst diagnosis.

METHODS

We identified studies with PCF obtained by EUS before surgery, with cysts classified as mucinous and nonmucinous according to surgical specimens. A random-effects model was used for quantitative meta-analysis. Pooled sensitivities, specificities, and summary receiver operating characteristic (ROC) curve analysis were conducted.

RESULTS

For CEA, we included 31 studies with 5268 patients, of which 2083 were referred for surgery. For glucose, we included 4 studies with 345 patients, of which 275 were referred for surgery. Glucose performed better than CEA for mucinous cysts diagnosis (premalignant and malignant) with sensitivities of .90 (95% confidence interval [CI], .85-.94) and .67 (95% CI, .65-.70), specificities of .82 (95% CI, .72-.89) and .80 (95% CI, 0.76-0.83), and areas under the ROC curve of .96 and .79, respectively. Glucose had a higher sensitivity (90%), with uncommon false-negative results, making it an excellent biomarker to exclude a mucinous cyst. Sensitivity analysis demonstrated that the findings of the current meta-analysis are robust.

CONCLUSION

Glucose level in PCF is more accurate than CEA for preoperative diagnosis of mucinous cysts. It may become a useful first-line test, particularly in small cysts with a limited volume of PCF. Larger studies are awaited to confirm glucose as the single test for mucinous cyst diagnosis.

The Yield of String Sign in Differentiating Mucinous from Non-Mucinous Pancreatic Cysts: A Retrospective Cross-Sectional Study

Background and Objectives: The diagnosis of pancreatic cysts is mostly based on a combination of morphological appearance and fluid analysis of amylase and carcinoembryonic antigen (CEA). We aimed to assess the capability of the string sign in differentiating mucinous from non-mucinous pancreatic cysts. Materials and Methods: All patients who were referred for endoscopic ultrasound (EUS) for pancreatic cysts assessment from 2015 to 2020 were retrospectively analyzed. Results: Our cohort consisted of 112 patients. Of them, 92 patients (82.1%) had mucinous cystic neoplasms (group A) and 20 patients (17.9%) had non-mucinous cystic neoplasms (group B). The average age in groups A and B was 71.3 and 60.4 years, respectively. String sign was positive in 47 patients (51.1%) and negative in 21 patients (22.8%) in group A, while in group B, string sign was negative in 19 patients (95%). String sign showed significant correlation with the diagnosis of mucinous cystic neoplasms (OR 64.2, 95% CI 8.1-508.6, p = 0.0001). Cytology confirmed mucinous cystic neoplasms that included 32 patients; the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of string sign for mucinous cystic neoplasms were high, reaching 93.8%, 85.7%, 96.8%, and 75%, respectively, with an excellent accuracy rate of 92.3%. Conclusions: The string sign is highly accurate for predicting pancreatic mucinous cystic neoplasms, and should be used as an important aid for improving diagnostic accuracy.

KRAS/GNAS-testing by highly sensitive deep targeted next generation sequencing improves the endoscopic ultrasound-guided workup of suspected mucinous neoplasms of the pancreas

Pancreatic cysts or dilated pancreatic ducts are often found by cross-sectional imaging, but only mucinous lesions can become malignant. Therefore, distinction between mucinous and non-mucinous lesions is crucial for adequate patient management. We performed a prospective study including targeted next generation sequencing (NGS) of cell-free DNA in the diagnostic endoscopic ultrasound (EUS)-guided workup. Pancreatic cyst(s) or main duct fluid obtained by EUS-guided FNA was analysed by carcinoembryonic antigen (CEA), cytology and deep targeted NGS of 14 known gastrointestinal cancer genes (AKT1, BRAF, CTNNB1, EGFR, ERBB2, FBXW7, GNAS, KRAS, MAP2K1, NRAS, PIK3CA, SMAD4, TP53, APC) with a limit of detection down to variant allele frequency of 0.01%. Results were correlated to histopathology and clinical follow-up. One hundred and thirteen patients with pancreatic cyst(s) and/or a dilated pancreatic main duct (≥5 mm) were screened. Sixty-six patients had to be excluded, mainly due to inoperability or small cyst size (≤10 mm). Forty-seven patients were enrolled for further analysis. A final diagnosis was available in 27 cases including 8 negative controls. In 43/47 (91.5%) of patients a KRAS- and/or GNAS-mutation was diagnosed by NGS. 27.0% of the KRAS-mutated and 10.0% of the GNAS-mutated lesions harbored multiple mutations. KRAS/GNAS-testing by NGS, cytology, and CEA had a sensitivity and specificity of 94.7/100%, 38.1/100%, and 42.1/75.0%, respectively. KRAS/GNAS-testing was significantly superior to CEA (P = .0209) and cytology (P = .0016). In conclusion, KRAS/GNAS-testing by deep targeted NGS is a suitable method to distinguish mucinous from non-mucinous pancreatic lesions, suggesting its usage as a single diagnostic test. Results must be confirmed in a larger cohort.

Application of EUS-based techniques in the evaluation of pancreatic cystic neoplasms

Pancreatic cystic neoplasms (PCNs) are being detected increasingly frequently due to the widespread use of high-resolution abdominal imaging modalities. Some subtypes of PCNs have the potential for malignant transformation. Therefore, accurate diagnosis of PCNs is crucial to determine whether surgical resection or surveillance is the best management strategy. However, the current cross-section imaging modalities are not accurate enough to enable definite diagnoses. In the last decade, EUS-based techniques have emerged, aiming to overcome the limitations of standard cross-section imaging modalities. These novel EUS-based techniques were primarily designed to acquire distinct images to make radiological diagnoses, collect cyst fluid to undergo biochemical or molecular analyses, and obtain tissue to conclude the pathological diagnoses. In this article, we present a comprehensive and critical review of these emerging EUS techniques for the diagnosis of PCNs, with emphasis being placed on the advantages, feasibilities, diagnostic performances, and limitations of these novel techniques.

EUS is accurate in characterizing pancreatic cystic lesions; a prospective comparison with cross-sectional imaging in resected cases

Background

Imaging modalities for characterizing pancreatic cystic lesions (PCLs) is a known uncertainty. The aim of this prospective study was to compare the diagnostic performance of endoscopic ultrasound morphology, cytology and cyst fluid carcinoembryonic antigen (EUS-FNA-CEA) with cross-sectional imaging in resected PCLs.

Methods

The cross-sectional imaging and EUS-FNA-CEA results were collected in an academic tertiary referral centre using histology of the surgical specimen as the diagnostic standard.

Results

Of 289 patients undergoing evaluation for PCL with cross-sectional imaging and EUS-FNA between February 2007 and March 2017, 58 underwent surgical resection providing a final diagnosis of the PCLs: 45 mucinous, 5 serous, 1 pseudocyst, 2 endocrine, 2 solid pseudopapillary neoplasms and 3 other. EUS-FNA-CEA was more accurate than cross-sectional imaging in diagnosing mucinous PCLs (95% vs. 83%, p = 0.04). Ninety-two percent of the PCLs with high-grade dysplasia or adenocarcinoma were smaller than 3 cm in diameter. The sensitivity of EUS-FNA-CEA and cross-sectional imaging for detecting PCLs with high-grade dysplasia or adenocarcinoma were 33% and 5% (p = 0.03), respectively. However, there was no difference in accuracy between the modalities (62% vs. 66%, p = 0.79). The sensitivity for detecting pancreatic adenocarcinomas only was 64% for EUS-FNA-CEA and 9% for cross-sectional imaging (p = 0.03). Overall, EUS-FNA-CEA provided a correct diagnosis in more patients with PCLs than cross-sectional imaging (72% vs. 50%, p = 0.01).

Conclusions

EUS-FNA-CEA is accurate and should be considered a complementary test in the diagnosis of PCLs. However, the detection of PCLs with high-grade dysplasia or adenocarcinoma needs to be improved. Cyst size does not seem to be a reliable predictor of high-grade dysplasia or adenocarcinoma.

Electronic supplementary material

The online version of this article (10.1007/s00464-020-08166-3) contains supplementary material, which is available to authorized users.

Marker Identification of the Grade of Dysplasia of Intraductal Papillary Mucinous Neoplasm in Pancreatic Cyst Fluid by Quantitative Proteomic Profiling

The incidence of patients with pancreatic cystic lesions, particularly intraductal papillary mucinous neoplasm (IPMN), is increasing. Current guidelines, which primarily consider radiological features and laboratory data, have had limited success in predicting malignant IPMN. The lack of a definitive diagnostic method has led to low-risk IPMN patients undergoing unnecessary surgeries. To address this issue, we discovered IPMN marker candidates by analyzing pancreatic cystic fluid by mass spectrometry. A total of 30 cyst fluid samples, comprising IPMN dysplasia and other cystic lesions, were evaluated. Mucus was removed by brief sonication, and the resulting supernatant was subjected to filter-aided sample preparation and high-pH peptide fractionation. Subsequently, the samples were analyzed by LC-MS/MS. Using several bioinformatics tools, such as gene ontology and ingenuity pathway analysis, we detailed IPMNs at the molecular level. Among the 5834 proteins identified in our dataset, 364 proteins were differentially expressed between IPMN dysplasia. The 19 final candidates consistently increased or decreased with greater IPMN malignancy. CD55 was validated in an independent cohort by ELISA, Western blot, and IHC, and the results were consistent with the MS data. In summary, we have determined the characteristics of pancreatic cyst fluid proteins and discovered potential biomarkers for IPMN dysplasia.

The Utility of Endoscopic Ultrasound Fine Needle Aspiration in Pancreatic Cystic Lesions Diagnosis

The yield of biochemical analysis of pancreatic cysts fluid obtained via fine needle aspiration (FNA) is limited. We aimed to assess whether biochemical cyst analysis correlates with the endoscopic ultra-sonographic (EUS) diagnosis. A retrospective study including patients who underwent EUS-FNA was performed. Agreement level between EUS diagnosis and biochemical analysis was reported. One-hundred-and-eleven patients were included. For cyst CEA level, 42.4% of patients with endoscopic diagnosis of pancreatic mucinous cystic neoplasm (intraductal papillary mucinous neoplasm (IPMN) and mucinous cystic neoplasms (MCN)) had CEA level >192 ng/mL vs. 15.8% of patients who had another endoscopic diagnosis (chi square = 0.03) with poor agreement level (Kappa = 0.130). For the serous cystadenoma (SCA), the levels of amylase and CEA were defined as <250 unit/L and <5 ng/mL, respectively. Eight patients (57.1%) had amylase of <250 unit/L, while 42.9% had >250 unit/L (chi square = 0.007). The agreement level between EUS diagnosis of SCA and amylase level was poor (Kappa = 0.231). For cyst CEA level, 71.4% had CEA level <5 ng/mL vs. 28.6% who had CEA >5 ng/mL (chi square < 0.001) with fair agreement level (Kappa = 0.495). EUS-FNA for pancreatic cystic lesions poorly correlated with the EUS diagnosis. FNA should be considered in the setting of EUS worrisome findings.

Endoscopic Ultrasound-Guided Fine-Needle Aspiration Microhistology in Asymptomatic and Symptomatic Pancreatic Cystic Lesions

OBJECTIVE

This study aimed to analyze the usefulness of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) microhistology to detect malignancy in pancreatic cystic lesions (PCLs).

METHODS

Patients with PCLs were identified and submitted to EUS-FNA from January 2010 to January 2017. The percentage of samples suitable for diagnostic classification by microhistology and the positive and negative likelihood ratios to detect malignancy in asymptomatic (APC) and symptomatic (SPC) PCLs were determined.

RESULTS

Endoscopic ultrasound-guided fine-needle aspiration was performed in 510 patients. The resulting material was processed by microhistology and useful for diagnosis in 432 (84.2%). Clinical characteristics of APC (341) and SPC (169) revealed that APC patients were younger (P = 0.004) and had smaller PCLs (23 vs 35 mm; P < 0.001). In APC, we found more preneoplastic (38.7% vs 30.2%; P = 0.0016) and a lower number of malignant PCLs (8.2% vs 24.3%; P < 0.001). In APC and SPC, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of microhistology to detect malignancy were 71.4%, 99.7%, 95.2%, 97.5%, and 97.4% (k = 0.80) and 58.5%, 96.9%, 85.7%, 87.9%, and 87.6%, respectively.

CONCLUSIONS

Endoscopic ultrasound-guided fine-needle aspiration was technically feasible. Microhistology was especially useful to detect neoplastic or malignant PCLs in APC patients.

Endoscopic ultrasonography for the evaluation of pancreatic cystic neoplasms

Endoscopic ultrasonography (EUS) is a modality with high spatial resolution that enables comprehensive observation of the entire pancreas and plays an important role in the diagnosis of pancreatic lesions. Recent advances in diagnostic imaging methods such as ultrasound, computed tomography, and magnetic resonance imaging have increased the incidental detection of pancreatic cystic lesions (PCLs). EUS has been recognized as an essential diagnostic method for the detection and evaluation of PCLs. EUS has two important roles: as a detailed (high-resolution) imaging diagnostic method and as an approach for collecting cyst fluid content by EUS-guided fine needle aspiration for pathological diagnosis or biomarker evaluation. Furthermore, in recent years, the usefulness of contrast-enhanced EUS for the differential diagnosis of PCLs or evaluation of grade of malignancy, and a novel imaging technique called needle-based confocal laser endomicroscopy to observe intraductal structures through a needle, has been reported. An understanding of the morphological characteristics of PCLs depicted by ultrasound imaging and of the benefits and limitations of EUS diagnosis in daily practice is needed.

Cross Validation of the Monoclonal Antibody Das-1 in Identification of High-Risk Mucinous Pancreatic Cystic Lesions

BACKGROUND & AIMS

Although pancreatic cystic lesions (PCLs) are frequently and incidentally detected, it is a challenge to determine their risk of malignancy. In immunohistochemical and enzyme-linked immunosorbent assay (ELISA) analyses of tissue and cyst fluid from pancreatic intraductal papillary mucinous neoplasms, the monoclonal antibody Das-1 identifies those at risk for malignancy with high levels of specificity and sensitivity. We aimed to validate the ability of Das-1 to identify high-risk PCLs in comparison to clinical guidelines and clinical features, using samples from a multicenter cohort.

METHODS

We obtained cyst fluid samples of 169 PCLs (90 intraductal papillary mucinous neoplasms, 43 mucinous cystic neoplasms, and 36 non-mucinous cysts) from patients undergoing surgery at 4 tertiary referral centers (January 2010 through June 2017). Histology findings from surgical samples, analyzed independently and centrally re-reviewed in a blinded manner, were used as the reference standard. High-risk PCLs were those with invasive carcinomas, high-grade dysplasia, or intestinal-type intraductal papillary mucinous neoplasms with intermediate-grade dysplasia. An ELISA with Das-1 was performed in parallel using banked cyst fluid samples. We evaluated the biomarker's performance, generated area under the curve values, and conducted multivariate logistic regression using clinical and pathology features.

RESULTS

The ELISA for Das-1 identified high-risk PCLs with 88% sensitivity, 99% specificity, and 95% accuracy, at a cutoff optical density value of 0.104. In 10-fold cross-validation analysis with 100 replications, Das-1 identified high-risk PCLs with 88% sensitivity and 98% specificity. The Sendai, Fukuoka, and American Gastroenterological Association guideline criteria identified high-risk PCLs with 46%, 52%, and 74% accuracy (P for comparison to Das-1 ELISA <.001). When we controlled for Das-1 in multivariate regression, main pancreatic duct dilation >5 mm (odds ratio, 14.98; 95% confidence interval, 2.63-108; P < .0012), main pancreatic duct dilation ≥1 cm (odds ratio, 47.9; 95% confidence interval, 6.39-490; P < .0001), and jaundice (odds ratio, 6.16; 95% confidence interval, 1.08-36.7; P = .0397) were significantly associated with high-risk PCLs.

CONCLUSIONS

We validated the ability of an ELISA with the monoclonal antibody Das-1 to detect PCLs at risk for malignancy with high levels of sensitivity and specificity. This biomarker might be used in conjunction with clinical guidelines to identify patients at risk for malignancy.

Cyst fluid glucose: An alternative to carcinoembryonic antigen for pancreatic mucinous cysts

Pancreatic cystic lesions (PCLs) have been increasingly recognized in clinical practice. Although inflammatory cysts (pseudocysts) are the most common PCLs detected by cross-sectional imaging modalities in symptomatic patients in a setting of acute or chronic pancreatitis, incidental pancreatic cysts with no symptoms or history of pancreatitis are usually neoplastic cysts. For these lesions, it is imperative to identify mucinous cysts (intraductal papillary mucinous neoplasms and mucinous cystic neoplasms) due to the risk of their progression to malignancy. However, no single imaging modality alone is sufficient for a definitive diagnosis of all PCLs. The cyst fluid obtained by endoscopic ultrasound-guided fine needle aspiration provides additional information for the differential diagnosis of PCLs. Current recommendations suggest sending cyst fluid for cytology evaluation and measurement of carcinoembryonic antigen (CEA) levels. Unfortunately, the sensitivity of cytology is greatly limited, and cyst fluid CEA has demonstrated insufficient accuracy as a predictor of mucinous cysts. More recently, cyst fluid glucose has emerged as an alternative to CEA for distinguishing between mucinous and nonmucinous lesions. Herein, the clinical utility of cyst fluid glucose and CEA for the differential diagnosis of PCLs was evaluated.

Age and cystic size are associated with clinical impact of endoscopic ultrasonography-guided fine-needle aspiration on the management of pancreatic cystic neoplasms

Objectives: The clinical impact of endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) in managing pancreatic cystic neoplasms (PCNs) remains controversial. The aim of this study was to identify which patients with PCNs would benefit from EUS-FNA. Methods: A retrospective study was performed on patients with PCNs who underwent EUS-FNA between January 2009 and June 2018. A discordant or a consistent diagnosis after EUS-FNA was analyzed and was correlated with the clinical demographic data and cystic features. Predictors of the change in the diagnosis after EUS-FNA were analyzed. Results: One hundred eighty-eight cases of PCNs were analyzed. EUS-FNA changed the diagnosis in 45.7% of all patients with PCNs and 54.5% patients with presumed branch ductal type intraductal papillary mucinous neoplasm (BD-IPMN) and impacted the recommendation in 35.6% of patients with PCNs and 50.5% patients with BD-IPMN. Patients with a discordant diagnosis after EUS-FNA were younger in age (54.8 ± 12.6 vs. 61.2 ± 14.2; p=.037) and had a cyst size larger than 3 cm than patients with a consistent diagnosis after EUS-FNA. The only worrisome feature (WF) that differed between patients with a discordant and a consistent diagnosis after EUS-FNA was the main pancreatic duct (MPD) between 5 and 9 mm (p=.013). In multivariate analysis, a cyst size >3 cm and age were independent predictors of diagnostic changes after EUS-FNA (OR: 5.33, 95% CI: 1.79-15.88, p = .003; OR: 0.96, 95% CI: 0.93-0.99, p  =  .031). Conclusions: EUS-FNA made a significant change in the management of nearly half of the patients with PCNs, especially in younger patients and in patients with a cyst size larger than 3 cm.

Univariate and classification analysis reveals potential diagnostic biomarkers for early stage ovarian cancer Type 1 and Type 2

Biomarkers for early detection of ovarian tumors are urgently needed. Tumors of the ovary grow within cysts and most are benign. Surgical sampling is the only way to ensure accurate diagnosis, but often leads to morbidity and loss of female hormones. The present study explored the deep proteome in well-defined sets of ovarian tumors, FIGO stage I, Type 1 (low-grade serous, mucinous, endometrioid; n = 9), Type 2 (high-grade serous; n = 9), and benign serous (n = 9) using TMT-LC-MS/MS. Data are available via ProteomeXchange with identifier PXD010939. We evaluated new bioinformatics tools in the discovery phase. This innovative selection process involved different normalizations, a combination of univariate statistics, and logistic model tree and naive Bayes tree classifiers. We identified 142 proteins by this combined approach. One biomarker panel and nine individual proteins were verified in cyst fluid and serum: transaldolase-1, fructose-bisphosphate aldolase A (ALDOA), transketolase, ceruloplasmin, mesothelin, clusterin, tenascin-XB, laminin subunit gamma-1, and mucin-16. Six of the proteins were found significant (p < .05) in cyst fluid while ALDOA was the only protein significant in serum. The biomarker panel achieved ROC AUC 0.96 and 0.57 respectively. We conclude that classification algorithms complement traditional statistical methods by selecting combinations that may be missed by standard univariate tests. SIGNIFICANCE: In the discovery phase, we performed deep proteome analyses of well-defined histology subgroups of ovarian tumor cyst fluids, highly specified for stage and type (histology and grade). We present an original approach to selecting candidate biomarkers combining several normalization strategies, univariate statistics, and machine learning algorithms. The results from validation of selected proteins strengthen our prior proteomic and genomic data suggesting that cyst fluids are better than sera in early stage ovarian cancer diagnostics.

Endoscopic diagnosis of cystic lesions of the pancreas

Endoscopic methods are increasingly used in the diagnosis of cystic lesions of the pancreas. The two major endoscopic approaches are endoscopic ultrasonography (EUS) and transpapillary diagnosis. EUS-guided fine-needle aspiration cytology and EUS-guided fine needle-based confocal laser endomicroscopy have been used in the differential diagnosis of mucinous and non-mucinous pancreatic cysts. EUS is the most sensitive modality for detecting mural nodules (MN) in intraductal papillary mucinous neoplasms (IPMN). Contrast-enhanced harmonic EUS (CH-EUS), as an add-on to EUS, is useful for identifying and characterizing MN. Recent studies show that CH-EUS has a sensitivity of 60-100% and a specificity of 75-92.9% for diagnosing malignant cysts. Intraductal ultrasonography and peroral pancreatoscopy are especially useful for detecting MN and IPMN. A recent meta-analysis showed that cytological assessment of pancreatic juice using a transpapillary approach had a pooled sensitivity, specificity, and accuracy of 35.1%, 97.2%, and 92.9%, respectively, for diagnosing malignant IPMN. Further studies are warranted to determine the indications for each of these novel techniques in assessing cystic lesions of the pancreas.

Endoscopic ultrasound-guided through-the-needle microforceps biopsy in the evaluation of pancreatic cystic lesions: a multicenter study

Background and study aims  Accurate diagnosis and classification of pancreatic cysts (PCs) remains a challenge. The aims of this study were to: (1) evaluate the safety and technical success of a novel microforceps for EUS-guided through-the-needle biopsy (TTNB) of PCs; and (2) assess its diagnostic yield for mucinous PCs when compared to FNA cyst fluid analysis and cytology. Patients and methods  This was a multicenter retrospective analysis of 47 patients who underwent EUS-FNA and TTNB for PCs between January 2014 and June 2017. Technical success was defined as acquisition of a specimen adequate for cytologic or histological evaluation. Cyst fluid carcinoembryonic antigen (CEA) was used to initially categorize cysts as non-mucinous (CEA < 192 ng/mL) or mucinous (CEA ≥ 192 ng/mL). Final diagnosis was based on identifiable mucinous pancreatic cystic epithelium on cytology, microforceps histology and/or surgical histology when available. Results  Forty-seven patients with PCs (mean size 30.7 mm) were included. TTNB was successfully performed in 46 of 47 (97.9 %). Technical success was significantly lower with FNA (48.9 %) compared to TTNB (85.1 %) ( P  < .001). For cysts with insufficient amount of fluid for CEA (n = 19) or CEA < 192 ng/mL, the cumulative incremental diagnostic yield of a mucinous PC was significantly higher with TTNB vs. FNA (52.6 % vs 18.4 %; P  = .004). TTNB alone (34.4 %) diagnosed more mucinous PCs than either CEA ≥ 192 ng/mL alone (6.3 %) or when combined with FNA cytology (9.4 %). One episode of self-limited bleeding (2.1 %) and one of pancreatitis (2.1 %) occurred. Conclusions  EUS-TTNB is safe and effective for evaluating PCs. TTNB may help increase the diagnostic yield of mucinous PCs.

Endoscopic ultrasound-through-the-needle biopsy in pancreatic cystic lesions: A multicenter study

BACKGROUND AND AIM

Tissue acquisition in pancreatic cystic lesions (PCL) is the ideal method for diagnosis and risk stratification for malignancy of these lesions. Direct sampling from the walls of PCL with different devices has shown better results than cytology from cystic fluid. We carried out a retrospective, multicenter study to evaluate the feasibility, safety, and diagnostic yield of a micro-forceps, specifically designed to be used through a 19-gauge needle after endoscopic ultrasonography (EUS)-guided puncture of PCL.

METHODS

We retrospectively collected data from patients who underwent EUS-through-the-needle biopsy (EUS-TTNB) in PCL at six referral centers.

RESULTS

The sampling procedure was carried out in 56 patients (mean age 57.5 ± 13.1 years, M:F 17:39), and was technically successful in all of them (100%; 95% confidence interval [CI], 94-100%). Adverse events occurred in 9/56 (16.1%; 95% CI, 8-28%) patients, with self-limited intracystic hemorrhage the most common (7/56, 12.5%; 95% CI, 5-24%). All adverse events were mild, and resolved without any specific intervention. Specimens were considered adequate for histological diagnosis in 47/56 (83.9%; 95% CI, 72-92%). In two of these patients, despite the histological adequacy, a diagnosis could not be reached. In two other cases, a specimen sufficient for a cytological diagnosis was obtained. Overall diagnostic yield by combining cytological and histological samples was 47/56 (83.9%; 95% CI, 72-92%).

CONCLUSION

EUS-TTNB with micro-forceps in PCL is feasible, safe, and has a high diagnostic yield. Future prospective studies are needed to better assess the clinical impact of EUS-TTNB on the management of PCL.

The Role of Endoscopic Ultrasound in the Diagnosis of Cystic Lesions of the Pancreas

A precise diagnosis of the nature of pancreatic cystic neoplasm (PCN) is crucial since it determines the patients in need of rapid surgical resection as well as those who can be followed up, and, accordingly, the frequency and modalities of surveillance. Endoscopic ultrasound (EUS) and especially fine needle aspiration (FNA) are invasive methods, with specific adverse events occurring in 2.7-5%. Thus, they should only be used as a third-line tool in the absence of characteristic radiographic features on computed tomography (CT) scan and magnetic resonance imaging (MRI). The most difficult aspects of differential diagnosis are: intraductal papillary mucinous neoplasm (IPMN) versus chronic pancreatitis; unifocal IPMN versus serous cystic neoplasm (SCN); macrocystic SCN versus mucinous cystic neoplasm (MCN); cystic neuroendocrine tumors versus MCN; solid serous cystadenoma versus neuroendocrine tumors versus small solid pseudopapillary tumors; pseudocyst versus MCN; low-grade, high-grade, or invasive IPMN. When classical radiological and EUS features are not conclusive, EUS-FNA may be helpful by analyzing cytological, chemical, and/or molecular data. The addition of EUS-FNA to CT scan and MRI increased the overall accuracy for diagnosing PCN by 36 and 54%, respectively. Analysis of molecular markers in pancreatic cyst fluid might increase the limited accuracy of EUS-FNA by using cytology and chemical and/or tumor marker analysis alone. Current evidence suggests that contrast-enhanced EUS (CH-EUS) is highly accurate for distinguishing non-neoplastic cysts from neoplastic cysts. CH-EUS might also be useful for distinguishing mural epithelial nodules from mucinous clots. Needle-based confocal laser endomicroscopy (nCLE) images a target tissue at a subcellular level of resolution, providing real-time in-vivo optical biopsy. nCLE is feasible during EUS-FNA and allows in-vivo diagnosis of PCN with high accuracy. In conclusion, EUS is a third-line tool in the diagnosis of PCN. Clinical context as well as careful evaluation of CT scan and magnetic resonance cholangiopancreatography images by specialized radiologists are crucial in the diagnosis process. Nowadays it is inconceivable to skip these steps.

Solid Papillary Neoplasm of the Pancreas: A Case Report

Solid pseudopapillary neoplasm of the pancreas, solid and cystic, is a rare disease compared to ductal adenocarcinoma. The tumor most often affects women of African race aged in their twenties or thirties. We report the case of a 48-year-old man affected by solid pseudopapillary neoplasm of the pancreas treated by distal splenopancreasec-tomy. The patient was discharged on the 10th postoperative day in good general condition, feeling normal and with blood chemistry values within normal limits. The main characteristic differentiating papillary tumors of the pancreas from ductal adenocarcinoma is that in the latter case surgical eradication is a definitive solution and no other treatment is required, as confirmed by our case and those reported in the literature.

Quantitative proteomic analysis of pancreatic cyst fluid proteins associated with malignancy in intraductal papillary mucinous neoplasms

Background

The application of advanced imaging technologies for identifying pancreatic cysts has become widespread. However, accurately differentiating between low-grade dysplasia (LGD), high-grade dysplasia (HGD), and invasive intraductal papillary mucinous neoplasms (IPMNs) remains a diagnostic challenge with current biomarkers, necessitating the development of novel biomarkers that can distinguish IPMN malignancy.

Methods

Cyst fluid samples were collected from nine IPMN patients (3 LGD, 3 HGD, and 3 invasive IPMN) during their pancreatectomies. An integrated proteomics approach that combines filter-aided sample preparation, stage tip-based high-pH fractionation, and high-resolution MS was applied to acquire in-depth proteomic data of pancreatic cyst fluid and discover marker candidates for IPMN malignancy. Biological processes of differentially expressed proteins that are related to pancreatic cysts and aggressive malignancy were analyzed using bioinformatics tools such as gene ontology analysis and Ingenuity pathway analysis. In order to confirm the validity of the marker candidates, 19 cyst fluid samples were analyzed by western blot.

Results

A dataset of 2992 proteins was constructed from pancreatic cyst fluid samples. A subsequent analysis found 2963 identified proteins in individual samples, 2837 of which were quantifiable. Differentially expressed proteins between histological grades of IPMN were associated with pancreatic diseases and malignancy according to ingenuity pathway analysis. Eighteen biomarker candidates that were differentially expressed across IPMN histological grades were discovered—7 DEPs that were upregulated and 11 that were downregulated in more malignant grades. HOOK1 and PTPN6 were validated by western blot in an independent cohort, the results of which were consistent with our proteomic data.

Conclusions

This study demonstrates that novel biomarker candidates for IPMN malignancy can be discovered through proteomic analysis of pancreatic cyst fluid.

Electronic supplementary material

The online version of this article (10.1186/s12014-018-9193-1) contains supplementary material, which is available to authorized users.

The Combination of Cyst Fluid Carcinoembryonic Antigen, Cytology and Viscosity Increases the Diagnostic Accuracy of Mucinous Pancreatic Cysts

Background/Aims

The objective of this study was to investigate the value of cyst fluid carcinoembryonic antigen (CEA) in combination with cytology and viscosity for the differential diagnosis of pancreatic cysts.

Methods

We retrospectively reviewed our data for patients who underwent endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and cyst fluid analysis. We investigated the sensitivity, specificity and accuracy of the combination of cyst fluid CEA, cytology and viscosity testing.

Results

A total of 177 patients underwent EUS-FNA and cyst fluid analysis. Of these, 48 subjects were histologically and clinically confirmed to have pancreatic cysts and were therefore included in the analysis. Receiver operator curve analysis demonstrated that the optimal cutoff value of cyst fluid CEA for differentiating mucinous versus nonmucinous cystic lesions was 48.6 ng/mL. The accuracy of cyst fluid CEA (39/48, 81.3%) was greater than the accuracy of cytology (23/45, 51.1%) or the string sign (33/47, 70.2%). Cyst fluid CEA in combination with cytology and string sign assessment exhibited the highest accuracy (45/48, 93.8%).

Conclusions

Cyst fluid CEA was the most useful single test for identifying mucinous pancreatic cysts. The addition of cytology and string sign assessment to cyst fluid CEA increased the overall accuracy for the diagnosis of mucinous pancreatic cysts.

Assessment of morbidity and mortality associated with endoscopic ultrasound-guided fine-needle aspiration for pancreatic cystic lesions: A systematic review and meta-analysis

BACKGROUND AND AIM

With increased availability of imaging technology, detection of pancreatic cystic lesions (PCL) is on the rise. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) improves the diagnosis accuracy of PCL. Systematic evaluation of morbidity and mortality associated with EUS-FNA for PCL has not been carried out. We conducted a systematic review and meta-analysis of morbidity and mortality associated with EUS-FNA.

METHODS

A literature search for relevant English-language articles was conducted on PubMed and EMBASE databases. Main outcome measures for this analysis were adverse effects of diagnostic EUS-FNA, and the associated morbidity and mortality, in patients with PCL.

RESULTS

Forty studies, with a combined subject population of 5124 patients with PCL, satisfied the inclusion criteria. Overall morbidity as a result of adverse events of EUS-FNA was 2.66% (95% confidence interval [CI]: 1.84-3.62%), and the associated mortality was 0.19% (95% CI: 0.09-0.32%). Common post-procedure adverse events included pancreatitis 0.92% (95% CI: 0.63-1.28%), hemorrhage 0.69% (95% CI: 0.42-1.02%), pain 0.49% (95% CI: 0.27-0.79%), infection 0.44% (95% CI: 0.27-0.66%), desaturation 0.23% (95% CI: 0.12-0.38%) and perforation 0.21% (95% CI: 0.11-0.36%). There was no peritoneal seeding in our study. Incidence of adverse events associated with prophylactic periprocedural antibiotic use was 2.77% (95% CI: 1.87-3.85%).

CONCLUSIONS

EUS-FNA is a safe procedure for diagnosis of PCL and is associated with a relatively low incidence of adverse events. Most adverse events were mild, self-limiting, and did not require medical intervention.

Incidents and adverse events of endoscopic ultrasound-guided fine-needle aspiration for pancreatic cystic lesions

AIM

To evaluate the diagnostic value and safety mainly regarding incidents of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for pancreatic cystic lesions (PCLs).

METHODS

A total of 150 consecutive patients with suspected PCLs were prospectively enrolled from April 2015 to November 2016. We finally enrolled 140 patients undergoing EUS-FNA. We compared the diagnostic accuracy of EUS-FNA and pathological diagnosis, which is regarded as the gold standard, for PCLs. Patients undergoing EUS-FNA at least 1 wk preoperatively were monitored for incidents and adverse events to evaluate its safety.

RESULTS

There were 88 (62.9%) women and 52 (37.1%) men among 140 patients, with a mean age of 50.1 (± 15.4) years. There were 67 cysts located in the head/uncinate of the pancreas and 67 in the body/tail, and 6 patients had at least 1 cyst in the pancreas. There were 75 patients undergoing surgery and 55 undergoing EUS-FNA with interval at least 1 wk before other operations, with 3 patients undergoing the procedure twice. The accuracy of EUS-FNA in differentiating benign and malignant lesions was 97.3% (73/75), while the accuracy of characterizing PCL subtype was 84.0% (63/75). The incident rate was 37.9% (22/58), whereas only 1 AE was observed in 58 cases.

CONCLUSION

EUS-FNA is effective and safe for diagnosis of PCLs, however procedure-related incidents are common. Caution should be taken in patients undergoing EUS-FNA.

Diagnosis of pancreatic cystic lymphangioma in an 11-year-old boy with endoscopic ultrasound-guided fine needle aspiration: A case report

Introduction: Pancreatic cystic lymphangioma (PCL) is an extremely rare benign tumor of lymphatic origin. Traditionally, it is diagnosed at surgery performed on a patient with a retroperitoneal cyst of unclear etiology. However, recently a few single case reports showed PCL was successfully diagnosed by endoscopic ultrasound with fine-needle aspiration (EUS-FNA). Case Report: We present a new case of PCL in an 11-year-old boy who came to our hospital for swelling of the body. A contrast-enhanced computed tomography scan revealed a 7.7×4.5 cm cystic lesion involving head and neck of the pancreas. EUS-FNA was subsequently performed and diagnosis of PCL was made based on result of cytological examination and measurement of aspirate. Conclusion: In agreement with previous reports, we show that EUS-FNA confirmed the cystic lesion in pancreas and further provided the gross, biochemical and cytological features supporting accurate diagnosis of PCL.

Tumor Markers in Pancreatic Cystic Fluids for Diagnosis of Malignant Cysts

Background and aim

Early diagnosis of premalignant or malignant pancreatic cysts is essential to improve prognosis. Sampling of pancreatic cyst fluid by fine-needle aspiration during endoscopic ultrasonography (EUS) enables cytopathological examination combined with biochemical analysis. This study aimed to provide an aid based on biological markers for the preoperative management of patients with pancreatic cysts.

Methods

Pancreatic fluids obtained by EUS-guided fine-needle aspiration from 115 patients with cystic lesions were assayed for amylase, lipase, carcinoembryonic antigen (CEA), CA 19-9 and CA 72-4. In addition, chromogranin A (CgA) and neuron-specific enolase (NSE) were measured in 28 fluid samples.

Results

ROC curve analysis of the different markers for diagnosis of mucinous cysts showed that CEA had the highest area under the curve (0.93, 95% CI 0.87-0.97), with a sensitivity and specificity of 89% and 93%, respectively, at the cutoff value of 317 μg/L. The CgA and NSE concentrations in 5 NET cysts (median values of 210 [63-492] and 68.5 [9-496] μg/L, respectively) were higher than in 23 other cysts (median values of 8 [7-828] and 2.7 [0.5-35.8] μg/L, respectively) (p = 0.0015 and p = 0.0045, respectively).

Conclusions

CEA is the best marker for identifying a cyst as mucinous. In case of low levels of CEA, our results suggest that CgA and NSE measurements may be helpful in the diagnosis of a neuroendocrine tumor and therefore deserve further investigation.

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.

Diffusion-Weighted Magnetic Resonance Imaging in Distinguishing Between Mucin-Producing and Serous Pancreatic Cysts

OBJECTIVE

The aim of this study was to evaluate the feasibility and reproducibility of diffusion-weighted imaging in distinguishing between mucin-producing and serous pancreatic cysts.

METHODS

Forty-four pancreatic cysts (43 patients, 27 women; mean age, 57 years; 26 mucin-producing cysts, 18 serous cysts) that underwent histological examination or cyst analysis after diffusion-weighted magnetic resonance imaging were retrospectively reviewed. Three blinded readers independently evaluated signal intensity and apparent diffusion coefficient (ADC). Intraobserver and interobserver agreements were calculated. Fisher exact test and Welch t test were used to compare signal intensity and ADC values, respectively, with pathological results. Receiver operating characteristic analysis was used to determine diagnostic accuracy of various thresholds for ADC. A P value less than 0.05 was considered statistically significant.

RESULTS

Mean ADC values of the mucin-producing cysts were 3.26 × 10, 3.27 × 10, and 3.35 × 10 mm/s for the 3 readers, respectively. Mean ADC values of the serous cysts were 2.86 × 10, 2.85 × 10, and 2.85 × 10 mm/s for the 3 readers, respectively. Differences in ADC values between the 2 cyst groups were 12.4%, 12.9%, and 14.8% for the 3 readers, respectively (P < 0.001). Intraobserver and interobserver agreement was excellent. A threshold ADC of 3 × 10 mm/s resulted in correct identification of cysts in 77% to 81% of cases, with sensitivity and specificity ranging between 84% and 88% and 66% and 72%, respectively.

CONCLUSIONS

Diffusion-weighted imaging may be a helpful tool in distinguishing between mucin-producing and serous pancreatic cysts.

Role of biochemistry and cytological analysis of cyst fluid for the differential diagnosis of pancreatic cysts: A retrospective cohort study

BACKGROUND

Management of pancreatic cysts is based on neoplastic-nonneoplastic discrimination. Endoscopic ultrasound (EUS) enables to differentiate neoplastic-nonneoplastic lesions and also allows fine-needle aspiration (FNA). In this study, we aim to assess feasibility and clinical relevance of cytological and biochemical analysis in differential diagnosis of cystic pancreatic lesions in patients who had undergone endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) due to pancreatic cysts.

METHODS

Participants were 96 patients who had undergone EUS-FNA for differential diagnosis of pancreatic cysts. Pancreatic cysts were classified as benign-mucinous, nonmucinous, and malignant according to patient history, physical examination, EUS appearance, and cystic fluid assessment. Tumor markers (CEA, CA(cancer antigens) 72.4, CA 19-9) , amylase, lipase and cytological assesment were compared between 3 different groups. Receiver-operating characteristics (ROC) curves were constructed to identify appropriate cut-off values.

RESULTS

Fluid CEA and CA 72.4 levels for benign-mucinous and malignant cysts were significantly higher than for nonmucinous cysts (P ≤ 0.04). A cut-off CEA level of 207 ng/mL differentiated mucinous etiology with a sensitivity of 72.7%, specificity of 97.7%, and accuracy of 89.5%. The sensitivity, specificity, and accuracy of the CA 72.4 cut-off level of 3.32 ng/mL were 80%, 69.5%, and 73.6%, respectively.

CONCLUSION

Cyst fluid CEA and CA 72.4 levels have a high accuracy in discriminating mucinous from nonmucinous cysts. When combined with cytology their accuracy rate increases.

A Gastric Glycoform of MUC5AC Is a Biomarker of Mucinous Cysts of the Pancreas

Molecular indicators to specify the risk posed by a pancreatic cyst would benefit patients. Previously we showed that most cancer-precursor cysts, termed mucinous cysts, produce abnormal glycoforms of the proteins MUC5AC and endorepellin. Here we sought to validate the glycoforms as a biomarker of mucinous cysts and to specify the oligosaccharide linkages that characterize MUC5AC. We hypothesized that mucinous cysts secrete MUC5AC displaying terminal N-acetylglucosamine (GlcNAc) in either alpha or beta linkage. We used antibody-lectin sandwich assays to detect glycoforms of MUC5AC and endorepellin in cyst fluid samples from three independent cohorts of 49, 32, and 66 patients, and we used monoclonal antibodies to test for terminal, alpha-linked GlcNAc and the enzyme that produces it. A biomarker panel comprising the previously-identified glycoforms of MUC5AC and endorepellin gave 96%, 96%, and 87% accuracy for identifying mucinous cysts in the three cohorts with an average sensitivity of 92% and an average specificity of 94%. Glycan analysis showed that MUC5AC produced by a subset of mucinous cysts displays terminal alpha-GlcNAc, a motif expressed in stomach glands. The alpha-linked glycoform of MUC5AC was unique to intraductal papillary mucinous neoplasms (IPMN), whereas terminal beta-linked GlcNAc was increased in both IPMNs and mucinous cystic neoplasms (MCN). The enzyme that synthesizes alpha-GlcNAc, A4GNT, was expressed in the epithelia of mucinous cysts that expressed alpha-GlcNAc, especially in regions with high-grade dysplasia. Thus IPMNs secrete a gastric glycoform of MUC5AC that displays terminal alpha-GlcNAc, and the combined alpha-GlcNAc and beta-GlcNAc glycoforms form an accurate biomarker of mucinous cysts.

Endoscopic ultrasound of pancreatic tumors

Computed tomography (CT) and endoscopic ultrasound (EUS) are the two most effective techniques for the assessment of pancreatic cancers. CT has revolutionized the field of tumor imaging in pancreatic cancer and is now a well-established imaging technique for diagnosis and staging. However, EUS still plays an important role in several situations, especially when the diagnosis is uncertain or when histopathological confirmation of the lesion is needed. Similarly, regarding cystic lesions, magnetic resonance imaging and CT have very good performances but are often inadequate because the diagnosis can be difficult to establish, while the consequences for the patient are major. New biopsy needles, the use of elastography and ultrasonographic contrast agents, and confocal laser endomicroscopy can also provide additional and essential information to improve diagnosis confidence of pancreatic lesions with EUS.

Impact of endoscopic ultrasonography (EUS) and EUS-guided fine-needle aspiration on the management of pancreatic cystic lesions

BACKGROUND AND STUDY AIMS

Endoscopic ultrasonography (EUS) and EUS-guided fine-needle aspiration (EUS-FNA) are well-recognized techniques for the study of pancreatic cystic lesions (PCLs). However, little evidence exists on their impact on clinical care. The aim of this study is to determine how often EUS and EUS-FNA alter the diagnosis and management of patients with PCLs.

PATIENTS AND METHODS

Eight physicians expert in pancreatic diseases were asked to report their diagnoses and management recommendations for 49 different PCLs. Clinical information was sequentially disclosed in a stepwise manner - progressively from clinical data plus computed tomography or MRI (level 1), to EUS (level 2) and EUS-FNA results including cytology, carcinoembryonic antigen, and amylase levels (level 3).

RESULTS

EUS led to a change in the diagnosis and management in 30% [95% confidence interval (CI): 26-35%] and 19% (95% CI: 16-23%) of cases, respectively, usually to a more intensive approach (14%; 95% CI: 11-18%). EUS-FNA altered the diagnosis and management in an additional 39% (95% CI: 34-44%) and 21% (95% CI: 17-25%) of the evaluations, respectively. EUS-FNA also increased the consensus in the diagnosis among the specialists that ranged from fair with computed tomography/MRI (κ-index=0.32) to substantial with EUS-FNA (κ-index=0.43).

CONCLUSION

EUS and EUS-FNA impact the diagnosis and management of patients with PCLs; therefore, both are necessary in the workup of these patients. EUS-FNA markedly improves the agreement between physicians in terms of diagnosis, but not management. This study highlights the need for more research and standardization in the field.

Diagnostic potential of tumor DNA from ovarian cyst fluid

We determined whether the mutations found in ovarian cancers could be identified in the patients' ovarian cyst fluids. Tumor-specific mutations were detectable in the cyst fluids of 19 of 23 (83%) borderline tumors, 10 of 13 (77%) type I cancers, and 18 of 18 (100%) type II cancers. In contrast, no mutations were found in the cyst fluids of 18 patients with benign tumors or non-neoplastic cysts. Though large, prospective studies are needed to demonstrate the safety and clinical utility of this approach, our results suggest that the genetic evaluation of cyst fluids might be able to inform the management of the large number of women with these lesions.

DOI:http://dx.doi.org/10.7554/eLife.15175.001

More than a third of women develop ovarian cysts during their lifetimes. The vast majority of these cysts are harmless, but a small number are caused by ovarian cancers. These cancers often produce no symptoms until the disease has spread throughout the abdomen or to other organs, so many women go undiagnosed until their chances of being successfully treated are low. Currently, there is no reliable way to determine whether an ovarian cyst is cancerous without performing surgery. As a result, many women undergo unnecessary, invasive surgeries for harmless ovarian cysts.

Tumors shed cells and cell fragments into any fluid that surrounds them. Fluids from cysts in the pancreas, kidney, and thyroid are routinely examined to identify whether they contain cancerous cells. Now, Wang, Sundfeldt et al. show that ovarian cancers also shed DNA into the surrounding cyst fluid. Furthermore, mutations found in this DNA can provide valuable information about whether the cysts are cancerous.

The study was performed by extracting DNA from the fluid in ovarian cysts that had been surgically removed from 77 women. Of these cysts, 10 were harmless cysts, 12 were benign tumors, 31 were invasive cancers, and 24 were so-called borderline tumors, which fall somewhere between the benign tumors and invasive cancers. Only cysts associated with the borderline tumors and invasive cancers need to be surgically removed. Here, Wang, Sundfeldt et al. report that DNA mutations that are characteristic of ovarian cancers were found in 87% of the cysts associated with borderline tumors and invasive cancers. In contrast, these mutations were not found in any of the cysts that do not require surgery.

Fluid can be extracted from an ovarian cyst with a needle during an outpatient visit. Therefore, the results presented by Wang, Sundfeldt et al. suggest a relatively straightforward way of testing the DNA from ovarian cysts before deciding whether surgery is really necessary. First, however, larger studies that follow women with cysts over time will be necessary to confirm that this type of testing is effective and safe.

DOI:http://dx.doi.org/10.7554/eLife.15175.002