Cyst fluid analysis obtained by EUS-guided FNA in the evaluation of discrete cystic neoplasms of the pancreas: a prospective single-center experience

Optimal carcinoembryonic antigen (CEA) cutoff values in the diagnosis of neoplastic mucinous pancreatic cysts differ among assays

AIM

Pancreatic cyst fluid carcinoembryonic antigen (CEA) is a pivotal test in the diagnosis and management of neoplastic mucinous cysts (NMC) of the pancreas. Cyst fluid CEA levels of 192 ng/mL have been widely used to identify NMC. However, CEA values are unique to and significantly differ between individual assays with various optimal cutoffs reported in the literature for NMC. Here, we investigate the optimal CEA cut-off value of pancreatic cysts from two different assays to identify differences in thresholds.

METHODS

Pancreatic cyst fluid CEA levels, CEA assay platform (Beckman Dxl (BD) or Siemens Centaur XP (SC)), and clinical/pathological information were retrospectively collected. Cases were categorised into either NMC or non-NMC. Optimal CEA cut-off values were calculated via a receiver operator characteristic curve. Cut-off values were then identified separately by assay platform.

RESULTS

In total, 149 pancreatic cystic lesions with concurrent CEA values (SC: n=47; BD: n=102) were included. Histological correlation was available for 26 (17%) samples. The optimal CEA cut-off value for all samples at the study institution was 45.9 ng/mL (area under the curve (AUC)=86, Sn=85.7%, Sp=73.8%). When analysed separately by CEA assay, the cut-off values were 45.9 ng/mL (AUC=84.27, Sn=89.7%, Sp=71.4%) for BD and 24.4 ng/mL (AUC=77, Sn=81.8%, Sp=75%) for SC (p=0.48).

CONCLUSIONS

This study showed an optimal pancreas cyst CEA cut-off threshold of 45.9 ng/mL, which is lower than commonly cited literature with different cutoffs on the two separate platforms (BD: 45.9 ng/mL, SC: 24.4 ng/mL).

Intracystic Glucose Levels Appear Useful for Diagnosis of Pancreatic Cystic Lesions: A Systematic Review and Meta-Analysis

BACKGROUND

Carcinoembryonic antigen (CEA) in the pancreatic cystic fluid is the most important biomarker for differentiating mucinous from non-mucinous pancreatic cystic lesions (PCLs). However, recent studies have shown that glucose levels in pancreatic cystic fluid can discriminate mucinous from non-mucinous cysts.

AIMS

To perform a meta-analysis to determine the utility of intracystic fluid glucose of pancreatic mucinous cysts compared with intracystic CEA.

METHODS

We conducted a systematic review of the literature in the PubMed, OVID Medline, and Cochrane databases. This meta-analysis considers studies published up to October 2020.

RESULTS

Six studies comprising 506 patients were selected; 61.2% of the population was female. Of the 480 PCLs, 287 (59.7%) were mucinous. Pooled sensitivity and specificity of cystic fluid glucose levels for mucinous PCLs were 91% and 85%, respectively. The positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 6.33 and 0.11, respectively. Pooled diagnostic odds ratio (DOR) was 60.94. The pooled area under the summary receiver operating characteristic (SROC) curve was 0.959. Pooled sensitivity and specificity of pancreatic cystic fluid CEA levels were 61% and 93%. The PLR and NLR were 8.51 and 0.40, respectively. Pooled DOR was 23.52, and the pooled area under the SROC curve was 0.861.

CONCLUSION

Glucose has become a useful method and appears to be better than CEA for differentiating between mucinous PCLs and non-mucinous PCLs. We suggest that the analysis of glucose in PCLs be routinely performed for the differential diagnosis of these lesions.

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.

Cystic pancreatic lesions, the endless dilemma

Cystic pancreatic lesions involve a wide variety of pathological entities that include neoplastic and non-neoplastic lesions. The proper diagnosis, differentiation, and staging of these cystic lesions are considered a crucial issue in planning further management. There are great challenges for their diagnostic models. In our time, new emerging methods for this diagnosis have been discovered. Endoscopic ultrasonography-guided fine-needle aspiration cytology with chemical and molecular analysis of cyst fluid and EUS-guided fine needle-based confocal laser endomicroscopy, through the needle microforceps biopsy, and single-operator cholangioscopy/pancreatoscopy are promising methods that have been used in the diagnosis of cystic pancreatic lesions. Hereby we discuss the diagnosis of cystic pancreatic lesions and the benefits of various diagnostic models.

Biomarkers and Strategy to Detect Preinvasive and Early Pancreatic Cancer: State of the Field and the Impact of the EDRN

Patients afflicted with pancreatic ductal adenocarcinoma (PDAC) face a dismal prognosis, but headway could be made if physicians could identify the disease earlier. A compelling strategy to broaden the use of surveillance for PDAC is to incorporate molecular biomarkers in combination with clinical analysis and imaging tools. This article summarizes the components involved in accomplishing biomarker validation and an analysis of the requirements of molecular biomarkers for disease surveillance. We highlight the significance of consortia for this research and highlight resources and infrastructure of the Early Detection Research Network (EDRN). The EDRN brings together the multifaceted expertise and resources needed for biomarker validation, such as study design, clinical care, biospecimen collection and handling, molecular technologies, and biostatistical analysis, and studies coming out of the EDRN have yielded biomarkers that are moving forward in validation. We close the article with an overview of the current investigational biomarkers, an analysis of their performance relative to the established benchmarks, and an outlook on the current needs in the field. The outlook for improving the early detection of PDAC looks promising, and the pace of further research should be quickened through the resources and expertise of the EDRN and other consortia.See all articles in this CEBP Focus section, "NCI Early Detection Research Network: Making Cancer Detection Possible."

Confocal endomicroscopy for evaluation of pancreatic cystic lesions: a systematic review and international Delphi consensus report

Background and study aims  The aim of thi systematic review and consensus report is to standardize the practice of endoscopic ultrasound (EUS-guided needle-based confocal laser endomicroscopy (nCLE) for pancreatic cystic lesion (PCL) evaluation. Methods  We performed an international, systematic, evidence-based review of the applications, outcomes, procedural processes, indications, training, and credentialing of EUS-nCLE in management of PCLs. Based on available clinical evidence, preliminary nCLE consensus statements (nCLE-CS) were developed by an international panel of 15 experts in pancreatic diseases. These statements were then voted and edited by using a modified Delphi approach. An a priori threshold of 80 % agreement was used to establish consensus for each statement. Results  Sixteen nCLE-CS were discussed. Thirteen (81 %) nCLE-CS reached consensus addressing indications (non-communication PCL meeting criteria for EUS-FNA or with prior non-diagnostic EUS-FNA), diagnostic outcomes (improved accuracy for mucinous PCLs and serous cystadenomas with substantial interobserver agreement of image patterns), low incidence of adverse events (fluorescein-associated and pancreatitis), procedural processes (nCLE duration, manipulation of needle with probe), and training (physician knowledge and competence). Conclusion  Based on a high level of agreement pertaining to expert consensus statements, this report standardizes the practice of EUS-nCLE. EUS-nCLE should be systematically considered when EUS-FNA is indicated for PCL evaluation.

Endoscopic Ultrasound-Guided Fine Needle Aspiration Cytologic Evaluation of Intraductal Papillary Mucinous Neoplasm and Mucinous Cystic Neoplasms of Pancreas

OBJECTIVES

To evaluate the role of endoscopic ultrasound-guided fine needle aspiration cytology in identifying mucinous cystic lesions (MCLs) in histologically proven cases of intraductal papillary mucinous neoplasm (IPMN) or mucinous cystic neoplasm (MCN) and risk of malignancy associated with each cytologic category based on the Papanicolaou Society of Cytopathology (PSC) guidelines.

METHODS

All resected cases with histologic diagnosis of IPMN or MCN at our institution from January 1, 2004, to August 31, 2019, with associated cytology were included. Available cytology slides of nondiagnostic (ND), negative/benign (BN), and atypical cytology (AC) cases were reviewed and reclassified based on the PSC guidelines.

RESULTS

A total of 120 cases were identified, including 57 IPMNs with low-grade or moderate dysplasia (LGD/MD) and high-grade dysplasia (HGD), 34 MCNs with LGD/MD or HGD, and 29 IPMNs with invasive malignancy. After cytology slide review and reclassification, we observed that ND and BN cases were paucicellular and lacked ancillary testing (carcinoembryonic antigen levels or KRAS mutation analysis). The risk-of-malignancy rates were 33% for ND, 11% for BN, 28.5% for AC, 17% for MCL, and 100% for suspicious/positive cytologic diagnosis.

CONCLUSIONS

A multidisciplinary approach including combined use of cytology and ancillary testing is helpful in establishing a diagnosis of MCL and identifying associated malignancy.

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.

Epidemiology, clinical features and diagnostic work-up of cystic neoplasms of the pancreas: Interim analysis of the prospective PANCY survey

INTRODUCTION

A prospective survey to evaluate the diagnostic workup of cystic pancreatic neoplasms (CPNs) according to the Italian guidelines.

METHODS

An online data sheet was built.

RESULTS

Fifteen of the 1385 patients (1.1%) had non cystic neoplastic lesions. Forty percent (518/1295) had at least one 1st degree relative affected by a solid tumor of the digestive and extra-digestive organs. Symptoms/signs associated with the cystic lesion were present in 24.5% of the patients. The cysts were localized in the head of the pancreas in 38.5% of patients. Of the 2370 examinations (1.7 examinations per patient) which were carried out for the diagnosis, magnetic resonance imaging was performed as a single test in 48.4% of patients and in combination with endoscopic ultrasound in 27% of the cases. Of the 1370 patients having CPNs, 89.9% had an intraductal papillary mucinous neoplasm (IPMN) (70.1% a branch duct IPMN, 6.2% a mixed type IPMN and 4.6% a main duct IPMN), 12.7% had a serous cystadenoma, 2.8% a mucinous cystadenoma, 1.5% a non-functioning cystic neuroendocrine neoplasm, 0.7% a solid-pseudopapillary cystic neoplasm, 0.3% a cystic adenocarcinoma, and 1.2% an undetermined cystic neoplasm. Seventy-eight (5.7%) patients were operated upon after the initial work-up.

CONCLUSIONS

This prospective study offers a reliable real-life picture of the diagnostic work-up CPN.

Pancreas Cystic Lesions

This article outlines the principles behind the management of pancreatic cystic lesions. We outline what the general surgeon needs to know in managing and triaging these patients. It is our feeling that the general surgeon is often the first line of evaluation of these complex patients and a working knowledge of the different types of cysts is critical to safe care of the patient.

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%.

Spectral CT Imaging in the Differential Diagnosis of Small Bowel Adenocarcinoma From Primary Small Intestinal Lymphoma

PURPOSE

To investigate the value of dual-energy spectral computed tomography (CT) imaging in the differential diagnosis of small bowel adenocarcinoma (SBA) from primary small intestinal lymphoma (PSIL).

MATERIALS AND METHODS

We retrospectively analyzed the images of 27 SBA cases and 15 PSIL cases. These patients underwent spectral CT imaging in the arterial phase (AP) and venous phase (VP). CT attenuation values of tumors at different energy levels were measured to generate spectral attenuation curve and to calculate curve slope (λ_HU). Iodine concentration (IC) in tumors at AP and VP were measured and normalized to that of aorta as normalized iodine concentration (NIC). Independent samples t test was used to analyze the spectral CT parameters; Receiver operating characteristic curves were generated to evaluate the diagnostic efficacy of each parameter.

RESULTS

There were significant differences between SBA and PSIL in IC (2.09 ± 0.71 vs 1.33 ± 0.15 mg/ml), NIC (0.20 ± 0.06 vs 0.13 ± 0.02) and slope (λ_HU) (2.78 ± 1.06 vs 1.86 ± 0.30) in AP and (1.86 ± 0.68 vs 1.37 ± 0.18 mg/ml for IC; 0.47 ± 0.13 vs 0.33 ± 0.02 for NIC and 2.00 ± 0.56 vs 1.50 ± 0.26 for λ_HU) in VP (all p < 0.05). For the CT value measurement, there were significant differences between SBA and PSIL in the 40-60keV energy range (p < 0.05), but not in the 70-140keV range (p > 0.05). Using 1.38 mg/ml as a threshold value for iodine concentration at AP, one could obtain the area-under-curve of 0.93 for receiver operating characteristic study and sensitivity of 94% and specificity of 85% for differentiating SBA from PSIL. The sensitivity and specificity values were significantly higher than the respective values of 62% and 60% with the conventional CT numbers at 70keV.

CONCLUSION

Quantitative parameters obtained in spectral CT, especially iodine concentration in AP, provide high accuracy for differentiating SBA from PSIL.

Endoscopic ultrasound-guided fine needle aspiration in diagnosis of cystic pancreatic lesions

BACKGROUND AND STUDY AIMS

pancreatic cysts are commonly found lesions and proper diagnosis is very important for planning further management. The study aims to evaluate the role of cyst fluid amylase and tumour markers as cancer antigen (CA 19-9) and carcinoembryonic antigen (CEA) in addition to mucin stain in diagnosing pancreatic cysts and differentiating malignant from benign lesions.

PATIENTS AND METHODS

This prospective study was conducted on 184 patients diagnosed to have pancreatic cystic lesions from January 2013 to January 2018. Fluid analysis for CA 19-9, CEA, amylase, mucin stain and cytopathology were done. We compared these data with the final diagnosis based on histopathology after surgical resection, positive cytopathology and long period of follow up of the patients for at least 18 months.

RESULTS

The highest AUC was that of cystic CEA with cut-off value of 160 ng/ml; it had a sensitivity of 60.4% and a specificity of 85%. The best cut-off value for cystic CA 19-9 was 1318 U/ml with a sensitivity of 64.1% and a specificity of 68.1%. The cut-off value of cyst amylase level was 5500 U/L, with 84.2% sensitivity and 37.1% specificity. The sensitivity of mucin stain in detecting mucinous cystic neoplasm was 85.45%, specificity was 86.05% with accuracy 85.87%.

CONCLUSION

Cyst fluid analysis by investigating amylase, mucin, CA 19-9, CEA and EUS examination improves the diagnosis of different pancreatic cysts.

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.

Early Detection of Pancreatic Cancer: Opportunities and Challenges

Most patients with pancreatic ductal adenocarcinoma (PDAC) present with symptomatic, surgically unresectable disease. Although the goal of early detection of PDAC is laudable and likely to result in significant improvement in overall survival, the relatively low prevalence of PDAC renders general population screening infeasible. The challenges of early detection include identification of at-risk individuals in the general population who would benefit from longitudinal surveillance programs and appropriate biomarker and imaging-based modalities used for PDAC surveillance in such cohorts. In recent years, various subgroups at higher-than-average risk for PDAC have been identified, including those with familial risk due to germline mutations, a history of pancreatitis, patients with mucinous pancreatic cysts, and elderly patients with new-onset diabetes. The last 2 categories are discussed at length in terms of the opportunities and challenges they present for PDAC early detection. We also discuss current and emerging imaging modalities that are critical to identifying early, potentially curable PDAC in high-risk cohorts on surveillance.

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.

Managing Incidental Pancreatic Cysts

PURPOSE OF REVIEW

The goal of this review is to critically analyze the current literature regarding the management of incidental pancreatic cysts. Given their increased rates of detection due to the frequent use of cross-sectional imaging, correctly identifying the subset of high risk lesions that are appropriate for surgical resection is critical. However, the existing consensus and societal guidelines discussed in this review lack high quality data to create evidence-based recommendations, making achieving this important aim challenging.

RECENT FINDINGS

Several recent studies have focused on the natural history of pancreatic cysts and defining the role of endoscopic ultrasound, which remains unclear. EUS-guided diagnostic tools include molecular analysis of obtained fluid; EUS-guided FNA, FNB, and intracystic forceps biopsy of the cyst wall; and confocal endomicroscopy. While their precise role in diagnosing pancreatic cystic neoplasms remains to be defined, they represent promising innovations that may play a future role in cyst assessment and management. Large, long-term, prospective studies of incidentally identified pancreatic cysts are essential to fully understand their natural history and potential for neoplastic progression. Given the absence of such data at present, an individualized patient approach is recommended.

Pancreatic Cystic Neoplasms: Different Types, Different Management, New Guidelines

Pancreatic cystic neoplasms (PCN) include different types of cysts with various biological behavior. The most prevalent PCN are intraductal papillary mucinous neoplasm (IPMN), mucinous cystic neoplasm (MCN), and serous cystic neoplasm (SCN). Management of PCN should focus on the prevention of malignant progression, while avoiding unnecessary morbidity of surgery. This requires specialized centers with dedicated multidisciplinary PCN teams. The malignant potential of PCN varies enormously between the various types of PCN. A combination of computed tomography, magnetic resonance imaging/magnetic resonance cholangiopancreatography, and endoscopic ultrasound with or without fine needle aspiration is typically needed before a reliable diagnosis can be made. Several guidelines discuss the management of PCN; however, most of these are non-evidence-based without clear consensus on the optimal treatment and follow-up strategy. The 2018 European guidelines on PCN are the first evidence-based guidelines to include IPMN, MCN, SCN, and all other PCN. This guideline advises a more conservative approach to side-branch IPMN and MCN smaller than 40 mm and more often a surgical approach in IPMN with a main duct dilatation beyond 5 mm. The goal of this review is to summarize the different types and management of the most common PCN based on the current literature and guidelines.

Endoscopic ultrasound cytologic brushing vs endoscopic ultrasound - fine needle aspiration for cytological diagnosis of cystic pancreatic lesions. A multicenter, randomized open-label trial

INTRODUCTION

the incidence of cystic pancreatic lesions (CPL) in the asymptomatic population is increasing. Achieving a preoperative diagnosis of CPL still remains a challenge.

OBJECTIVES

to evaluate the diagnostic accuracy of the cytological diagnosis of CPL from samples obtained by cytology brush versus standard endoscopic ultrasound fine needle aspiration (EUS-FNA).

METHODS

a multicenter, randomized, open-label trial was performed of EUS-cytology brush (EUS-EB) versus EUS-FNA for the cytological diagnosis of CPL. Patients that underwent EUS-FNA with a CPL > 15 mm were included and randomized into two groups: group I, EUS-EB; group II, EUS-FNA. The final diagnosis was based on the histological evaluation of surgical specimens and clinical parameters, imaging and a five year follow-up in non-operated patients. The main outcome was the diagnostic accuracy of both methods. Secondary outcomes were the diagnostic adequacy of specimens and the rate of adverse events. Data were compared using the Chi-squared test. An intention to treat (ITT) and per-protocol (PP) analysis were performed.

RESULTS

sixty-five patients were included in the study, 31 in group I and 34 in group II. Three patients initially randomized to group I were changed to group II as it was impossible to obtain a sample using the brush. The mean size of the CPL was 28.2 mm (range 16-60 mm). The diagnostic accuracy of EUS-EB was not superior to EUS-FNA, neither in the ITT nor the PP analysis (44.8% vs 41.1%, p = 0.77 and 38.4% vs 45.9%, p = 0.55).

CONCLUSIONS

EUS-EB does not improve the diagnostic accuracy of CPL in comparison with EUS-FNA.

Present status and perspectives of endosonography 2017 in gastroenterology

Endoscopic ultrasound has become an essential tool in modern gastroenterology and abdominal surgery. Compared with all other endoscopic methods, it has the most potential for innovation and its future looks bright. Thus, we compiled this summary of established and novel applications of endoscopic ultrasound methods to inform the reader about what is already possible and where future developments will lead in improving patient care further. This review is structured in four parts. The first section reports on developments in diagnostic endoscopic ultrasound, the second looks at semi-invasive endoscopic ultrasound, and the third discusses advances in therapeutic endoscopic ultrasound. An overview on the future prospects of endoscopic ultrasound methods concludes this article.

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.

Quantitative assessment of the degree of differentiation in colon cancer with dual-energy spectral CT

OBJECTIVE

To evaluate dual-energy spectral CT imaging in evaluating the degree of differentiation in colon cancer.

METHODS

Forty-seven colon cancer patients underwent spectral CT during arterial phase (AP) and portal venous phase (PP), and were characterized pathologically differentiated to well-differentiated (A, n = 18) and poorly differentiated or undifferentiated carcinoma group (B, n = 29). Lesion iodine concentration (IC) was measured and normalized to that of aorta (NIC). CT numbers were measured and the slope (λ _HU) of the spectral HU curve was calculated. These parameters were statistically compared between the two groups. ROC curves were used to evaluate their diagnostic efficacies.

RESULTS

There were significant differences in IC (1.01 ± 0.20 vs. 1.59 ± 0.57 mg/ml), NIC (0.12 ± 0.03 vs. 0.19 ± 0.09), λ _HU (1.41 ± 0.29 vs. 2.03 ± 0.85), and CT number at 70 keV (48.61 ± 9.03HU vs. 63.97 ± 15.86HU) between groups A and B in AP (p < 0.05), but no difference in PP. Using IC = 1.13 mg/ml in AP as the threshold, one obtained a sensitivity of 81.8% and a specificity of 71.4% for differentiating well-differentiated from poorly differentiated or undifferentiated carcinoma. These values were statistically higher than those (64.7% and 62.3%) using CT number at 70 keV.

CONCLUSION

Spectral CT imaging parameters (IC, NIC, and λ _HU) in AP provide improved accuracy for evaluating the degrees of differentiation in colon cancer than CT number at 70 keV.

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.

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.

Preliminary study of single-operator cholangioscopy for diagnosing pancreatic cystic lesions

BACKGROUND AND AIMS

Advances in imaging technology have improved the annual detection rate of pancreatic cystic lesions (PCLs), but the preoperative diagnosis of PCLs remains unclear. Thus, the usefulness of single-operator cholangioscopy (SOC) as a diagnostic imaging tool for PCLs is worth investigating. We performed an intracystic visual examination of PCLs using SOC to determine the diagnostic value of SOC for PCLs.

METHODS

In this retrospective observational study, PCLs were confirmed using a diagnostic imaging modality. Patients who underwent an EUS-guided through-the-needle fiberoptic pancreatic cystoscopy and SOC examination and those whose lesion type was definitively diagnosed were included (n = 43). If the cystic fluid was turbid, a physiologic saline solution was injected into the cyst, and a SOC fiberoptic probe was inserted through a 19-gauge needle to observe the wall of the intracystic cavity and its contents. The characteristics were recorded, and the cystic fluid and biopsy specimens were further assessed by performing liquid-based cytologic and histopathologic examinations. Particularly, histopathologic examinations were performed in patients who underwent surgery.

RESULTS

Intracystic characteristics of the confirmed cases of PCLs (43 patients) were identified through intracystic visual examination with SOC. The clarity of cyst fluid is a prerequisite for imaging by SOC. The tree-like branching pattern of blood vessel distribution may be a serous cystic neoplasm-specific characteristic. Intracystic papilla-like structure is an important characteristic for diagnosing mucinous cystic neoplasms.

CONCLUSIONS

The identified imaging characteristics such as blood vessel distribution on the intracystic wall and the contents of different PCLs observed under the SOC probe can provide useful information for diagnosing PCLs. SOC could be an important ancillary imaging test of PCLs by EUS.

Metastatic tonsillar squamous cell carcinoma masquerading as a pancreatic cystic tumor and diagnosed by EUS-guided FNA

Metastatic carcinoma to the pancreas is uncommon and head and neck squamous carcinoma metastatic to the pancreas is extremely rare. Metastatic squamous cell carcinoma to the pancreas presents a unique diagnostic challenge: in addition to mimicking the rare primary squamous cell carcinoma of the pancreas based on cytologic, histologic, and immunohistochemical features, it may be mistaken for a cystic neoplasm of the pancreas because of its high predilection for cystic degeneration in metastatic sites. Herein, we report a case of tonsillar squamous cell carcinoma with a cystic pancreatic metastasis diagnosed by ultrasound-guided fine needle aspiration biopsy (EUS-FNA). This represents a third reported case of metastatic squamous cell carcinoma to the pancreas from the head and neck region. Metastatic squamous cell carcinoma should be considered in the differential diagnosis of EUS-FNA during evaluation of pancreatic cystic lesion.

Value of apparent diffusion coefficient for predicting malignancy of intraductal papillary mucinous neoplasms of the pancreas

PURPOSE

We aimed to explore the potential value of the whole tumor apparent diffusion coefficient (ADC) for discriminating between benign and malignant intraductal papillary mucinous neoplasms (IPMNs) of the pancreas.

METHODS

Forty-two patients underwent 1.5 T magnetic resonance imaging that included diffusion-weighted imaging (DWI, b=0.500 s/mm2). The mean, minimum, and maximum ADC values were measured for the whole tumor. The differences between benign and malignant IPMNs were calculated for the mean ADC, ADC-min, and ADC-max values. Receiver operating characteristics (ROC) analysis was conducted to evaluate their potential diagnostic performance.

RESULTS

Fifteen of 25 benign IPMNs demonstrated low or iso-signal intensity on DWI with a b value of 500 s/mm2 compared with normal pancreatic parenchyma, whereas all malignant IPMNs demonstrated high signal intensity. The mean value of ADC was significantly higher in benign IPMNs compared with malignant IPMNs (3.39×10-3 mm2/s vs. 2.39×10-3 mm2/s, P < 0.001), with an area under the ROC curve (AUC) of 0.92 (95% confidence interval [CI], 0.79-0.98). The ADC-min value of malignant IPMNs was also significantly lower than that of benign IPMNs (1.24×10-3 mm2/s vs. 2.58×10-3 mm2/s, P < 0.001), with an AUC of 0.94 (95% CI, 0.82-0.99). No marked difference was found between benign and malignant IPMNs for the ADC-max value (3.89×10-3 mm2/s vs. 3.78×10-3 mm2/s, P = 0.299).

CONCLUSION

Lower mean and minimum ADC values of the whole tumor might be potential predictors of malignant IPMNs of the pancreas.

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.

Role of endoscopic ultrasound-guided fine-needle aspiration cytology, viscosity, and carcinoembryonic antigen in pancreatic cyst fluid

Due to the advances and increased utility of abdominal cross-sectional imaging, the diagnosis of pancreatic cysts continues to increase. Many endosonographers, pancreatologists, and surgeons consider endoscopic ultrasound (EUS) to be an essential tool in the management of pancreatic cystic lesions (PCLs). EUS can help distinguish between mucinous and nonmucinous lesions and may identify the specific cyst type. EUS achieves these goals by delineating the cyst morphology, identifying high risk stigmata and worrisome features, and through image-guided fine-needle aspiration (FNA) and cyst fluid analysis. However, recent consensus statements have called to question the utility and diminished the role of EUS in this setting. The aim of this review is to assess the role and advances of EUS-FNA in pancreatic cyst fluid analysis, specifically in terms of fluid cytology, viscosity, and carcinoembryonic antigen (CEA) analysis.

Role of emerging molecular markers in pancreatic cyst fluid

Cystic lesions of the pancreas (CLPs) are increasingly diagnosed due to the growing utilization of cross-sectional imaging modalities. The differentiation between true cysts (epithelial tumors) and nonepithelial lesions (such as pseudocysts) relies on clinical and imaging characteristics, but more reliably obtained by endoscopic ultrasound (EUS) fine-needle aspiration. Due to their malignant potential, some of the true pancreatic cysts require further assessment and periodic follow-up. Therefore, it is important to establish a solid diagnosis at the time of detection of the various types of pancreatic cysts. Due to the limitations of cytology and biochemical markers in accurately classifying cyst pathology, the search for specific molecular markers associated with each type of cyst is ongoing. In this chapter, we will review some of the emerging molecular markers in pancreatic cystic fluid and their potential impact on endosonography and pancreatic cyst management.

Suboptimal accuracy of carcinoembryonic antigen in differentiation of mucinous and nonmucinous pancreatic cysts: results of a large multicenter study

BACKGROUND AND AIMS

The exact cutoff value at which pancreatic cyst fluid carcinoembryonic antigen (CEA) level distinguishes pancreatic mucinous cystic neoplasms (MCNs) from pancreatic nonmucinous cystic neoplasms (NMCNs) is unclear. The aim of this multicenter retrospective study was to evaluate the diagnostic accuracy of cyst fluid CEA levels in differentiating between MCNs and NMCNs.

METHODS

Consecutive patients who underwent EUS with FNA at 3 tertiary care centers were identified. Patients with histologic confirmation of cyst type based on surgical specimens served as the criterion standard for this analysis. Demographic characteristics, EUS morphology, FNA fluid, and cytology results were recorded. Multivariate logistic regression analysis to identify predictors of MCNs was performed. Receiver-operating characteristic (ROC) curves were generated for CEA levels.

RESULTS

A total of 226 patients underwent surgery (mean age, 61 years, 96% white patients, 39% female patients) of whom 88% underwent Whipple's procedure or distal pancreatectomy. Based on surgical histopathology, there were 150 MCNs and 76 NMCNs cases. The median CEA level was 165 ng/mL. The area under the ROC curve for CEA levels in differentiating between MCNs and NMCNs was 0.77 (95% confidence interval, 0.71-0.84, P < .01) with a cutoff of 105 ng/mL, demonstrating a sensitivity and specificity of 70% and 63%, respectively. The cutoff value of 192 ng/mL yielded a sensitivity of 61% and a specificity of 77% and would misdiagnose 39% of MCN cases.

CONCLUSIONS

Cyst fluid CEA levels have a clinically suboptimal accuracy level in differentiating MCNs from NMCNs. Future studies should focus on novel cyst fluid markers to improve risk stratification of pancreatic cystic neoplasms.

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

BACKGROUND

Carcinoembryonic antigen (CEA) is suggested as the single most useful EUS/EUS-FNA derived test for the diagnosis of mucinous pancreatic cysts.

STUDY AIMS

To investigate the yield and diagnostic performance of EUS/EUS-FNA on an intention to diagnose basis and to determine the utility of the recommended CEA and amylase cut-off values.

PATIENTS AND METHODS

A retrospective study of a prospectively maintained database of 433 procedures performed in a 10 year period. Diagnostic performance of EUS-FNA was determined in 133 procedures with a definite diagnosis.

RESULTS

CEA value was determined in significantly fewer procedures (58.6%) than EUS diagnosis was stated (83.4%; p < 0.0001), cyst fluid appearance recorded (89.4%) or adequate sample for cytology obtained (76.7%; p < 0.005). Median CEA was significantly higher in mucinous cysts than non-mucinous (175 ng/ml vs 3 ng/ml, p < 0.0001) and in malignant cysts compared to benign (8945 ng/ml vs 93 ng/ml, p < 0.001). On an intention-to-diagnose analysis, a CEA cut-off of 110 ng/ml was significantly less accurate (42.8%) than EUS diagnosis (67.7%), cytology (58.6%) or aspirate appearance (66.9%; p < 0.05 for all comparisons). However, the combination of EUS diagnosis, cytology and CEA provided higher sensitivity (91%), specificity (75%) and accuracy (85.7%) than each component test alone (p < 0.05 for all comparisons). Median amylase was significantly higher in benign compared to high-risk mucinous cysts ((11,429IU/L vs. 113IU/L; p < 0.05.

CONCLUSION

The combination of EUS, cytology and CEA performed well. Malignant cysts had a higher CEA value than benign cysts. On an intention to diagnose basis a CEA cut-off of 110 ng/ml performed poorly.

Imaging of Acute Pancreatitis

Acute pancreatitis is an acute inflammation of the pancreas. Several classification systems have been used in the past but were considered unsatisfactory. A revised Atlanta classification of acute pancreatitis was published that assessed the clinical course and severity of disease; divided acute pancreatitis into interstitial edematous pancreatitis and necrotizing pancreatitis; discerned an early phase (first week) from a late phase (after the first week); and focused on systemic inflammatory response syndrome and organ failure. This article focuses on the revised classification of acute pancreatitis, with emphasis on imaging features, particularly on newly-termed fluid collections and implications for the radiologist.

Discovery and Validation of Biomarkers That Distinguish Mucinous and Nonmucinous Pancreatic Cysts

The use of advanced imaging technologies for the identification of pancreatic cysts has become widespread. However, accurate differential diagnosis between mucinous cysts (MC) and nonmucinous cysts (NMC) consisting of pseudocysts (NMC1) and nonmucinous neoplastic cysts (NMC2) remains a challenge. Thus, it is necessary to develop novel biomarkers for the differential diagnosis of pancreatic cysts. An integrated proteomics approach yielded differentially expressed proteins in MC that were verified subsequently in 99 pancreatic cysts (21 NMC1, 41 NMC2, and 37 MC) using a method termed GeLC-stable isotope dilution-multiple reaction monitoring-mass spectrometry (GeLC-SID-MRM-MS) along with established immunoassay techniques. We identified 223 proteins by nanoscale liquid chromatography coupled to tandem mass spectrometry (nano LC/MS-MS). Nine candidate biomarkers were identified, including polymeric immunoglobulin receptor (PIGR), lipocalin 2 (LCN2), Fc fragment of IgG-binding protein (FCGBP), lithostathine-1-alpha (REG1A), afamin (AFM), chymotrypsin C (caldecrin; CTRC), amylase, alpha 2B (pancreatic; AMY2B), lectin, galactoside-binding, soluble, 3 binding protein (LGALS3BP), and chymotrypsin-like elastase family, member 3A (CELA3A), which were established as biomarker candidates for MC. In particular, we have shown that a biomarker subset, including AFM, REG1A, PIGR, and LCN2, could differentiate MC not only from NMC (including NMC1) but also from NMC2. Overall, the MS-based comprehensive proteomics approach used in this study established a novel set of candidate biomarkers that address a gap in efforts to distinguish early pancreatic lesions at a time when more successful therapeutic interventions may be possible.

Laparoscopic fenestration of pancreatic serous cystadenoma: Minimally invasive approach for symptomatic benign disease

Serous cystadenoma (SC) is a benign pancreatic cystic tumor. Surgical resection is recommended for symptomatic forms, but laparoscopic fenestration of large symptomatic macrocystic SC was not yet described in the literature. In this study, 3 female patients underwent laparoscopic fenestration for macrocystic SC (12-14 cm). Diagnosis was established via magnetic resonance imaging and endoscopic ultrasound, with intra-cystic dosage of tumors markers (ACE and CA19-9) in 2 patients. All patients were symptomatic and operated on 15-60 mo after diagnosis. Radiological evaluation showed constant cyst growth. Patients were informed about this new surgical modality that can avoid pancreatic resection. The mean operative time was 103 min (70-150 min) with one conversion. The post-operative course was marked by a grade A pancreatic fistula in one patient and was uneventful in the other two. The hospital stay was 3, 10, and 18 d, respectively. The diagnosis of macrocystic SC was histologically-confirmed in all cases. At the last follow-up (13-26 mo), all patients were symptom-free, and radiological evaluation showed complete disappearance of the cyst. Laparoscopic fenestration, as opposed to resection, should be considered for large symptomatic macrocystic SC, thereby avoiding pancreatic resection morbidity and mortality.

Cystic neoplasms of the pancreas; findings on magnetic resonance imaging with pathological, surgical, and clinical correlation

Pancreatic cysts are increasingly being identified by cross-sectional imaging studies. Pancreatic cystic lesions comprise a spectrum of underlying pathologies ranging from benign and pre-malignant lesions to frank malignancies. Magnetic resonance imaging with cholangiopancreatography is a non-invasive imaging modality used for the characterization of cystic pancreatic lesions. This article will review the most common pancreatic cystic neoplasms and the utility of MR imaging in the characterization of these cysts.

Gastric Duplication Cyst With Elevated Amylase: An Unusual Presentation Mimicking Pancreatic Cystic Neoplasm

Enteric duplication cysts (EDCs) are benign congenital anomalies that are found incidentally in adults. Gastric duplication cysts (GDCs) are the least common subtype of EDC, but when located near the pancreas, may resemble other neoplastic conditions. We report a case of GDC adjacent to the pancreas with high cystic fluid amylase and carcinoembryonic antigen (CEA) and 3 different epithelia (respiratory, gastric, and intestinal), all diagnosed via endoscopic ultrasound with fine-needle aspiration.

Cyst fluid amylase and CEA levels in the differential diagnosis of pancreatic cysts: a single-center experience with histologically proven cysts

OBJECTIVE

Cyst fluid amylase is a potential marker for pseudocysts and intraductal papillary mucinous neoplasms (IPMN). This study aimed to evaluate the diagnostic role of cyst fluid amylase and to determine the optimal cutoff values of cyst fluid amylase and carcinoembryonic antigen (CEA) for the differential diagnosis of pancreatic cysts.

METHODS

Based on the pancreatic cyst database at Massachusetts General Hospital, a total of 78 patients with histologically proven cysts [pancreatic pseudocyst (PP), n = 16; mucinous cystic neoplasm, mucinous cystic neoplasm (MCN), n = 22; IPMN, n = 40] were selected. Complete cyst fluid amylase and CEA values were analyzed.

RESULTS

Thirty two of 78 patients were male with median age of 60.4 years (range, 24-84). Cyst diameter ranged from 5 to 130 mm. For cyst fluid amylase, there was significant difference between PP and MCN (median, 30,034.50 vs. 4,723.50 U/L; p < 0.05) or IPMN (30,034.50 vs. 1,585.00; p = 0.001), but no difference between MCN and IPMN. For cyst fluid CEA, there was a significant difference between PP and MCN (median, 26.00 vs. 627.50 ng/mL; p < 0.001) or IPMN (26.00 vs. 356.50; p < 0.001). Median amylase and CEA values were significantly different between PP and mucinous neoplasms (MCN/IPMN) (p < 0.01 and p < 0.001). Optimal cutoff values of 6,800 U/mL for amylase and 50 ng/mL for CEA correlated with the crossover of the sensitivity and specificity curves for differentiating PP and mucinous neoplasms. The overall accuracies of cyst fluid amylase and CEA were 69 and 85%, respectively.

CONCLUSIONS

Cyst fluid amylase analysis does not differentiate between MCN and IPMN. The combination of cyst fluid CEA and amylase value may increase the diagnostic accuracy for differentiating mucinous neoplasms from pseudocysts.

Incidental pancreatic cysts: role of magnetic resonance imaging

The widespread adoption of multidetector computed tomography and magnetic resonance imaging (MRI) for evaluation of intraabdominal pathology has resulted to a steady increase in the number of incidentally discovered pancreatic cysts in clinical practice during the last decades. The differential diagnosis of these cysts is broad including pseudocysts, serous cystic neoplasms, mucinous cystic neoplasms, and intraductal papillary mucinous neoplasms. The MRI has an important role both in the initial characterization of incidentally detected pancreatic cysts and the follow-up of these lesions and has become an integral part of the diagnostic algorithm for pancreatic cysts at many institutions. The inherent soft-tissue contrast of magnetic resonance cholangiopancreatography provides the vehicle for providing a specific diagnosis in many pancreatic cysts. Furthermore, an MRI-based characterization of pancreatic cysts allows for selection of those cysts that are more likely to benefit from endoscopic ultrasound and fine-needle aspiration for analysis of the fluid contents. Moreover, small asymptomatic incidental pancreatic cysts without concerning MRI features such as internal septae and/or nodularity may be safely followed with serial imaging. The lack of risk associated to repeated exposure to ionizing radiation and its ability to characterize pancreatic cysts are strong arguments for selecting MRI as the preferred imaging modality for following up these lesions. However, the recommendations for imaging follow-up continue to evolve, and several of the proposed guidelines are reviewed in this manuscript.

Differential diagnosis of pancreatic serous oligocystic adenoma and mucinous cystic neoplasm with spectral CT imaging: initial results

AIM

To investigate the imaging characteristics of pancreatic serous oligocystic adenoma (SOA) and mucinous cystic neoplasms (MCNs) using spectral computed tomography (CT) and to evaluate whether quantitative information derived from spectral imaging can improve the differential diagnosis of these diseases.

MATERIALS AND METHODS

From February 2010 to June 2013, 44 patients (24 SOAs and 20 MCNs) who underwent spectral CT imaging were included in the study. Conventional characteristics and quantitative parameters were compared between the two disease groups. Logistic regression was used for multiparametric analysis. The receiver-operating characteristic curve was used to evaluate the diagnostic performance of single parameter and multiparametric analysis. Two radiologists diagnosed the diseases blinded and independently, without and with the information of the statistical analysis.

RESULTS

Tumour location, contour, size, and monochromatic CT values at 40 keV to 70 keV, iodine concentration, and effective atomic number (effective-Z) in the late arterial phase were the independent factors correlated with category. Multiparametric analysis with logistic regression showed that tumour size, location, and contour were the most effective variations, and obtained an area under the ROC curve (AUC) of 0.934. With the knowledge of statistical analysis, the accuracy of the first reader increased from 70.5% to 86.4%, and the accuracy of the second reader increased from 81.8% to 90.9%.

CONCLUSIONS

Although CT spectral imaging provided additional information and multiparametric analysis obtained better performance than single-parameter analysis in differentiating MCNs from SOAs, multiparametric analysis with the combination of quantitative parameters derived from CT spectral imaging did not improve the diagnostic performance. Tumour size, location, and contour played an important role in differentiating MCNs from SOAs.

Italian consensus guidelines for the diagnostic work-up and follow-up of cystic pancreatic neoplasms

This report contains clinically oriented guidelines for the diagnostic work-up and follow-up of cystic pancreatic neoplasms in patients fit for treatment. The statements were elaborated by working groups of experts by searching and analysing the literature, and then underwent a consensus process using a modified Delphi procedure. The statements report recommendations regarding the most appropriate use and timing of various imaging techniques and of endoscopic ultrasound, the role of circulating and intracystic markers and the pathologic evaluation for the diagnosis and follow-up of cystic pancreatic neoplasms.