内镜超声引导下细针穿刺细胞学及囊液癌胚抗原分析诊断胰腺囊性病变的价值

目的探讨内镜超声引导下细针穿刺（EUS-FNA）细胞学检查、囊液癌胚抗原（cEA）分析对区分胰腺囊性病变良恶性的诊断价值。方法对27例胰腺囊性病变患者行EUS-FNA细胞学检查和囊液CEA分析,绘制囊液CEA受试者工作特征曲线并通过Youden指数确定诊断临界值,以手术病理诊断为金标准,统计分析EUS、EUS-FNA细胞学及囊液CEA分析鉴别诊断胰腺囊性病变良恶性的敏感度、特异度、阳性预测值、阴性预测值和准确率。结果手术病理确诊良性病变14例、潜在恶性／恶性病变13例。EUS鉴别诊断胰腺囊性病变良恶性的准确率、敏感度、特异度、阳性预测值、阴性预测值分别为77．8％（21／27）、69．2％（9／13）、85．7％（12／14）、81．8％（9／11）、75．0％（12／16）;EUS-FNA细胞学上述指标分别为85．2％（23／27）、76．9％（10／13）、92．9％（13／14）、90．9％（10／11）、81．3％（13／16）;以囊液CEA值22．24ng／ml为诊断临界值,上述指标分别为74．1％（20／27）、84．6％（11／13）、64．3％（9／14）、68．8％（11／16）、81．8％（9／11）。结论EUS-FNA细胞学鉴别诊断胰腺囊性病变良恶性具有较高的准确率和特异度,而囊液CEA分析（诊断临界值22．24ng／m1）鉴别诊断胰腺囊性病变良恶性的敏感度较高,选择合适的胰腺囊液CEA分析诊断临界值结合EUS-FNA细胞学检查可以基本满足临床鉴别胰腺囊性病变良恶性的需要。     

Diagnosis of pancreatic cystic neoplasms: a report of the cooperative pancreatic cyst study

BACKGROUND & AIMS: Cysts of the pancreas display a wide spectrum of histology, including inflammatory (pseudocysts), benign (serous), premalignant (mucinous), and malignant (mucinous) lesions. Endoscopic ultrasonography (EUS) may offer a diagnostic tool through the combination of imaging and guided, fine-needle aspiration (FNA). The purpose of this investigation was to determine the most accurate test for differentiating mucinous from nonmucinous cystic lesions. METHODS: The results of EUS imaging, cyst fluid cytology, and cyst fluid tumor markers (CEA, CA 72-4, CA 125, CA 19-9, and CA 15-3) were prospectively collected and compared in a multicenter study using histology as the final diagnostic standard. RESULTS: Three hundred forty-one (341) patients underwent EUS and FNA of a pancreatic cystic lesion; 112 of these patients underwent surgical resection, providing a histologic diagnosis of the cystic lesion (68 mucinous, 7 serous, 27 inflammatory, 5 endocrine, and 5 other). Receiver operator curve analysis of the tumor markers demonstrated that cyst fluid CEA (optimal cutoff of 192 ng/mL) demonstrated the greatest area under the curve (0.79) for differentiating mucinous vs. nonmucinous cystic lesions. The accuracy of CEA (88 of 111, 79%) was significantly greater than the accuracy of EUS morphology (57 of 112, 51%) or cytology (64 of 109, 59%) (P < 0.05). There was no combination of tests that provided greater accuracy than CEA alone (P < 0.0001). CONCLUSIONS: Of tested markers, cyst fluid CEA is the most accurate test available for the diagnosis of mucinous cystic lesions of the pancreas.     

Combination of cyst fluid CEA and CA 125 is an accurate diagnostic tool for differentiating mucinous cystic neoplasms from intraductal papillary mucinous neoplasms

Background/objectivesDespite advances in imaging techniques, diagnosis and management of pancreatic cystic lesions still remains challenging. The objective of this study was to determine the utility of cyst fluid analysis (CEA, CA 19-9, CA 125, amylase, and cytology) in categorizing pancreatic cystic lesions, and in differentiating malignant from benign cystic lesions.MethodsA retrospective analysis of 68 patients with histologically and clinically confirmed cystic lesions was performed. Cyst fluid was obtained by surgical resection (n = 45) or endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) (n = 23). Cyst fluid tumor markers and amylase were measured and compared between the cyst types.ResultsReceiver operating characteristic (ROC) curve analysis of the tumor markers demonstrated that cyst fluid CEA provided the greatest area under ROC curve (AUC) (0.884) for differentiating mucinous versus non-mucinous cystic lesions. When a CEA cutoff value was set at 67.3 ng/ml, the sensitivity, specificity and accuracy for diagnosing mucinous cysts were 89.2%, 77.8%, and 84.4%, respectively. The combination of cyst fluid CEA content >67.3 ng/ml and cyst fluid CA 125 content >10.0 U/ml segregated 77.8% (14/18) of mucinous cystic neoplasms (MCNs) from other cyst subtypes. On the other hand, no fluid marker was useful for differentiating malignant versus benign cystic lesions. Although cytology (accuracy 83.3%) more accurately diagnosed malignant cysts than CEA (accuracy 65.6%), it lacked sensitivity (35.3%).ConclusionsOur results demonstrate that cyst fluid CEA can be a helpful marker in differentiating mucinous from non-mucinous, but not malignant from benign cystic lesions. A combined CEA and CA 125 approach may help segregate MCNs from IPMNs.     

The utility and the safety of EUS-guided FNA in the evaluation of duplication cysts

BACKGROUND: Diagnosis of a foregut duplication cyst is of great clinical impact. A definitive diagnosis of a foregut duplication cyst can avert the need for major thoracic surgery in the otherwise asymptomatic individual. This study sought to evaluate the safety and the utility of EUS and EUS-guided FNA (EUS-FNA) in the diagnosis of foregut duplication cysts. METHODS: Over a period of 4 years, 4771 patients underwent EUS for various indications at two EUS referral centers. EUS findings were consistent with a mediastinal cyst in 30 cases. EUS-FNA was performed in 22 patients. A definitive diagnosis was established based on cytology, surgical pathology, and/or clinical follow-up. FNA was done with 22-gauge needles and antibiotic prophylaxis. RESULTS: The appearance of cyst contents on EUS ranged from completely anechoic (23 cases) to hypoechoic (7 cases). Hypoechoic cystic lesions contained echogenic foci. All anechoic lesions were confirmed as benign duplication cysts based on cytology, pathology, and clinical follow-up. Hypoechoic cystic lesions were confirmed to be benign duplication cysts in 4 cases. Three cases proved to be malignant or granulomatous necrotizing lymph nodes. No periprocedural complications occurred. CONCLUSIONS: Variation exists in the EUS appearance of benign mediastinal cysts. EUS-FNA of mediastinal cysts with smaller-gauge needles, and antibiotic prophylaxis appears safe and can provide a definitive diagnosis in atypical mediastinal cystic lesions.     

EUS diagnosis of cystic lesions of the pancreas

Summary Background. Cystic tumors of the pancreas are composed of benign, premalignant, malignant, and inflammatory lesions that are traditionally difficult to diagnose. Most of the tumors are initially detected on CT/US scanning, but often the morphological characteristics are insufficient for making a definitive diagnosis. Endoscopic ultrasound (EUS) may be an ideal tool for imaging of these lesions because it can provide highly detailed imaging without interference by bowel or air. Furthermore, EUS can direct fine needle aspiration of the lesions, providing cyst fluid for cytologic examination. The findings of cyst fluid cytology can be complemented by the use of cyst fluid tumor makers such as CEA. Using the morphologic appearance by endosonography, the results of cytology, and tumor marker analysis, EUS can often differentiate between benign, malignant, and inflammatory cystic lesions of the pancreas.     

Role of endoscopic ultrasonography in the diagnosis and treatment of cystic tumors of the pancreas

Endoscopic ultrasound (EUS) allows high resolution imaging of the pancreas. EUS is a very useful technique for evaluating morphological features of a cystic tumors of the pancreas. These features include thick wall type, tumor protruding type, thick septal type, microcystic type, thin septal type and simple type. Malignant cystic lesions may present as a hypoechoic cystic/solid mass or as a complex cyst and are frequently associated with a dilated main pancreatic duct. There is some overlap between EUS appearances of non-neoplastic and neoplastic cystic pancreatic lesions. EUS guided FNA of cystic pancreatic lesions can play an important role in the differential diagnosis of these lesions and deciding about the need for surgery by evaluating cytology and tumor markers such as CEA in cyst fluid. There is some emerging data on EUS guided treatment of cystic pancreatic tumors by injection of alcohol.     

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

Background and study aimspancreatic 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 methodsThis 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.ResultsThe 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%.ConclusionCyst fluid analysis by investigating amylase, mucin, CA 19-9, CEA and EUS examination improves the diagnosis of different pancreatic cysts.     

A comparative analysis of K-ras mutation and carcinoembryonic antigen in pancreatic cyst fluid

Background/aimsAnalysis of cystic fluid may be useful in distinguishing between benign and malignant cysts which has significant impact on their management. The aim of our study was to assess the diagnostic utility of carcinoembryonic antigen (CEA) and K-ras gene mutation in pancreatic cysts fluid.MethodsThe study included 56 patients with pancreatic cystic fluid collected for analysis. The cysts were classified as benign (simple cysts, pseudocysts, serous cystadenoma) - 39 patients or premalignant/malignant (mucinous cystadenoma, IPMN, cystadenocarcinoma) - 17 patients. The patients history, CEA fluid concentrations and presence of K-ras mutation were analyzed.ResultsCEA were higher in patients with malignant cysts (mean levels 238 ± 12.5 ng/ml; range 32.8–4985 ng/ml) compared to benign lesions (mean levels 34.5 ± 3.7 ng/ml; range 3.9–693 ng/ml; p < 0.001). K-ras mutation correctly classified 11 of 17 patients with premalignant/malignant lesions. It was also detected in 1 patient with final diagnosis of benign cyst (the sensitivity 64.7% and the specificity 97.4%; p < 0.01). If CEA and molecular analysis were combined in that cysts with either CEA level>45 ng/ml or presence of K-ras mutation, than 16 of 17 premalignant/malignant cysts were correctly identified (94.1%).ConclusionMolecular analysis of pancreatic cyst fluid adds diagnostic value to the preoperative diagnosis and should be considered when cyst cytologic examination is negative for malignancy.     

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

BACKGROUND: Accurate assessment of pancreatic cystic neoplasms is imperative before selecting available treatment options, such as surgical resection, drainage, or conservative therapy. Available modalities, CT and magnetic resonance imaging, have been inconsistent in diagnosis. Reports involving EUS and cyst fluid analysis have been encouraging, including studies of EUS features and/or cyst fluid analysis, which may differentiate pancreatic cystic neoplasms. OBJECTIVE: To retrospectively determine cyst fluid characteristics that differentiate cystic neoplasms. DESIGN: Patient evaluation included (1) EUS features (reported elsewhere) and (2) cyst fluid analysis (carcinoembryonic antigen [CEA], carbohydrate antigen 19-9 [CA 19-9], amylase and lipase, viscosity [VIS], mucin stain, and cytology). Exclusion criteria included the following: intraductal papillary mucinous tumor lesions, bloody cyst aspirate, neuroendocrine tumors, and patients without surgical histopathology. SETTING: Pancreatic Biliary Center, St Luke's Medical Center, Milwaukee, Wisconsin. PATIENTS: A total of 102 patients (60 women, 42 men; age, 23-76 years) presented for evaluation of pancreatic cystic neoplasm; 71 underwent surgical resection. RESULTS: Seventy-one of 102 patients who underwent surgery presented the following histopathologic correlates: 23 pseudocysts (PC), 13 serous cystadenoma (SCyA), 21 mucinous cystadenoma (MCyA), and 14 mucinous cystadenocarcinoma (MCyA-CA). Cyst fluid analysis of these patients showed the following: VIS was lower in PC (mean, 1.3) and SCyA (1.27) when compared with MCyA (1.84) and MCyA-CA (1.9). All mucinous neoplasms had VIS >1.6, whereas only 2 mucinous cystic neoplasms (MCN) had VIS = 1.6 (both PC). The CEA level was significantly higher in MCyA (adenoma [878 ng/mL], carcinoma [27,581 ng/mL]) vs PC (189 ng/mL), and SCyA (121 ng/mL). Amylase levels were higher in PC (7210 U/L) compared with cystic neoplasm (SCyA, 679 U/L; MCyA, 1605 U/L; MCyA-CA, 569 U/L). CONCLUSIONS: Differential diagnosis of pancreatic cystic neoplasm is significantly enhanced by cyst fluid analysis. Elevated CEA (> or =480 ng/mL) and VIS (>1.6) accurately predict MCN from SCyA and PC. Malignant from benign MCN can be differentiated by CEA levels > or =6000 ng/mL.     

Current status on the diagnosis and management of pancreatic cysts in the Asia-Pacific region: role of endoscopic ultrasound

Endoscopic ultrasound (EUS) and EUS-guided fine-needle aspiration (EUS-FNA) play increasingly prominent roles in the diagnosis and management of pancreatic cysts. The Asian Consortium of Endoscopic Ultrasound was recently formed to conduct collaborative research in this area. This is a review of literature on true pancreatic cysts. Due to the lack of systematic studies, there are no robust data on the true incidence of pancreatic cystic lesions in Asia and any change in over the recent decades. Certain EUS morphological features have been used to predict particular types of pancreatic cysts. Pancreatic cyst fluid viscosity, cytology, pancreatic enzymes, and tumor markers, in particular carcinoembryonic antigen, can aid in the diagnosis of pancreatic cysts. Hemorrhage and infection are the most common complications of EUS-FNA of pancreatic cysts. Pancreatic cysts can either be observed or resected depending on the benign or malignant nature, or malignant potential of the lesions. Guidelines from an international consensus did not require positive cytological findings to be present in their recommendation for resection, which included all mucinous cystic neoplasms, all main-duct intraductal papillary mucinous neoplasms (IPMN), all mixed IPMN, symptomatic side-branch IPMN, and side-branch IPMN larger than 3 cm. In patients with poor surgical risks, EUS-guided cyst ablation of mucinous pancreatic cysts is an alternative. As long-term prospective data on pancreatic cysts are still not available in Asia, management strategies are largely based on risk stratification by surgical risk and malignant potential. Gene expression profiling of pancreatic cyst fluid and confocal laser endomicroscopic examination of pancreatic cysts are novel techniques currently being studied.     

Concomitant pancreatic adenocarcinoma in a patient with branch-duct intraductal papillary mucinous neoplasm

Branch duct intraductal papillary mucinous neoplasms (BD-IPMN) are pre-malignant pancreatic cystic lesions which carry a small risk of malignant transformation within the cyst. Guidelines exist with respect to surveillance of the cysts using computed tomography, magnetic resonance imaging, and/or endoscopic ultrasound (EUS). There are reports that patients with IPMNs are at increased risk of developing pancreatic adenocarcinoma, which arises in an area separate to the IPMNs. We present two cases of pancreatic adenocarcinoma arising within the parenchyma, distinct from the IPMN-associated cyst, identified with EUS. This case report highlights that patients with BD-IPMN are at increased risk for pancreatic adenocarcinoma separate from the cyst and also the importance for endosonographers to carefully survey the rest of the pancreatic parenchyma separate from the cyst in order to identify small pancreatic adenocarcinomas.     

Endoscopic ultrasound and computer tomography are inaccurate methods of classifying cystic pancreatic lesions

BACKGROUND: Despite advances in imaging modalities, preoperative diagnosis of pancreatic cystic lesions remains difficult. AIM: To assess the accuracy of endoscopic ultrasound and computer tomography to preoperatively distinguish benign from potentially malignant and malignant pancreatic cystic lesions. METHODS: Photograph series obtained from endoscopic ultrasound examinations of 66 patients with cystic pancreatic lesions were blindly reviewed by three endoscopic ultrasonographers. Forty-one of those 66 patients also underwent a computer tomography scan at our institution, which was blindly reviewed by a single radiologist. Computer tomography and endoscopic ultrasound classification into benign and malignant and potentially malignant pancreatic cystic lesions was correlated with the final diagnosis, which was established by surgical pathology (n = 43), diagnostic fine needle aspiration (n = 13) or follow-up imaging (n = 10). Interobserver agreement was measured using kappa statistics. RESULTS: Endoscopic ultrasound classification by the three examiners into benign versus malignant or potentially malignant cystic lesions was correct in 65-67%. Interobserver agreement was 50%. Kappa values for pairs of endoscopic ultrasound examiners were 0.16, 0.43 and 0.53. Computer tomography classification was correct in 71% and in agreement with the endoscopic ultrasound classification in 56-61% (kappa 0.12 to 0.27). CONCLUSIONS: Endoscopic ultrasound and computer tomography cannot accurately distinguish between benign pancreatic cystic lesions and malignant or potentially malignant ones. There is poor-to-modest interobserver agreement in classifying these lesions.     

Rendimiento diagnóstico de la punción mediante ultrasonografía endoscópica de las lesiones quísticas del páncreas

IntroductionDespite 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 methodsRetrospective 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.ResultsFrom 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%).ConclusionThe 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%.     

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.     

Can EUS alone differentiate between malignant and benign cystic lesions of the pancreas?

OBJECTIVE: The aim of this study was to evaluate the ability of endoscopic ultrasound (EUS) alone to predict and differentiate malignant from benign cystic lesions of the pancreas. METHODS: From January, 1995, to August, 1999, 98 cases of pancreatic cystic lesions were evaluated by EUS; all of these were originally imaged by cross-sectional modalities that were not diagnostic. Among these, surgical/pathological correlation was available in 48 patients. The original endosonographic images were reviewed by two endosonographers who were blinded to each other's interpretation and to the surgical and pathological interpretation. The EUS images were assessed for the presence or absence of the following characteristics: 1) wall, 2) solid component, 3) septae, 4) lymphadenopathy, and 5) number of cysts. These characteristics were then correlated with the surgical and pathological findings and were assessed to determine if any were predictors of the lesion being benign or malignant. RESULTS: For reviewer A, the presence of a solid component by EUS was the only statistically significant predictor of malignancy (odds ratio = 4.73, 95% CI = 1.13-19.68, p = 0.03). However, 61% of patients with benign lesions were also interpreted by EUS to have a solid component. For reviewer B, none of the features were found to be significant predictors of a malignant lesion. When the results of both reviewers were combined, the presence of a solid component was not found to be a statistically significant predictor of malignancy (odds ratio = 1.046, 95% CI = 0.99-1.09, p = 0.07). CONCLUSION: Endosonographic features cannot reliably differentiate between benign and malignant cystic lesions of the pancreas after a nondiagnostic cross-sectional modality.     

Sensitivity of CT,MRI, and EUS-FNA/B in the preoperative workup of histologically proven left-sided pancreatic lesions

Background and objectivesLeft-sided pancreatic lesions are often treated surgically. Accurate diagnostic work-up is therefore essential to prevent futile major abdominal surgery. Large series focusing specifically on the preoperative work-up of left-sided pancreatic lesions are lacking. This surgical cohort analysis describes the sensitivity of CT, MRI, and EUS-FNA/B in the diagnostic work-up of left-sided pancreatic lesions.MethodsWe performed a post-hoc analysis of patients who underwent surgery for a left-sided pancreatic lesion between April 2010 and August 2017 and participated in the randomized CPR trial. Primary outcome was the sensitivity of CT, MRI, and EUS-FNA/B. Sensitivity was determined as the most likely diagnosis of each modality compared with the postoperative histopathological diagnosis. Additionally, the change in sensitivity of EUS versus EUS-FNA/B (i.e., cyst fluid analysis, and/or tissue acquisition) was measured.ResultsOverall, 181 patients were included (benign: 23%, premalignant: 27%, malignant: 50%). Most patients had solid lesions (65%). Preoperative imaging included CT (86%), MRI (41%), EUS (68%). Overall, CT and EUS-FNA/B reached a sensitivity of both 71%, compared with 66% for MRI. When EUS was combined with FNA/B, sensitivity rose from 64% to 71%. For solid lesions, CT reached the highest sensitivity (75%) when compared with MRI (70%) and EUS-FNA/B (69%). For cystic lesions, EUS-FNA/B reached the highest sensitivity (75%) when compared with CT and MRI (both 62%).ConclusionsCT is the most sensitive diagnostic modality for solid and EUS-FNA/B for cystic left-sided pancreatic lesions. EUS-FNA/B was associated with an increased sensitivity when compared to EUS alone.     

Endoscopic ultrasound elastography for evaluation of lymph nodes and pancreatic masses： A multicenter study

AIM： To evaluate the ability of endoscopic ultrasound （EUS） elastography to distinguish benign from malignant pancreatic masses and lymph nodes.
METHODS： A multicenter study was conducted and included 222 patients who underwent EUS examination with assessment of a pancreatic mass （n = 121） or lymph node （n = 101）, The classification as benign or malignant, based on the real time elastography pattern, was compared with the classification based on the B-mode EUS images and with the final diagnosis obtained by EUS-guided fine needle aspiration （EUS- FNA） and/or by surgical pathology. An interobserver study was performed.
RESULTS： The sensitivity and specificity of EUS elastography to differentiate benign from malignant pancreatic lesions are 92.3% and 80.0%, respectively, compared to 92.3% and 68.9%, respectively, for the conventional B-mode images. The sensitivity and specificity of EUS elastography to differentiate benign from malignant lymph nodes was 91.8% and 82.5%, respectively, compared to 78.6% and 50.0%, respectively, for the B-mode images. The kappa coefficient was 0.785 for the pancreatic masses and 0.657 for the lymph nodes.
CONCLUSION： EUS elastography is superior compared to conventional B-mode imaging and appears to be able to distinguish benign from malignant pancreatic masses and lymph nodes with a high sensitivity, specificity and accuracy. It might be reserved as a second line examination to help characterise pancreatic masses after negative EUS-FNA and might increase the yield of EUS-FNA for lymph nodes.     

Cyst fluid analysis in the differential diagnosis of pancreatic cystic lesions: a pooled analysis

BACKGROUND: Pancreatic cystic tumors commonly include serous cystadenoma (SCA), mucinous cystadenoma (MCA), and mucinous cystadenocarcinoma (MCAC). A differential diagnosis with pseudocysts (PC) can be difficult. Radiologic criteria are not reliable. The objective of the study is to investigate the value of cyst fluid analysis in the differential diagnosis of benign (SCA, PC) vs. premalignant or malignant (MCA, MCAC) lesions. METHODS: A search in PubMed was performed with the search terms cyst, pancrea, and fluid. Articles about cyst fluid analysis of pancreatic lesions that contained the individual data of at least 7 patients were included in the study. Data of all individual patients were combined and were plotted in scatter grams. Cutoff levels were determined. RESULTS: Twelve studies were included, which comprised data of 450 patients. Cysts with an amylase concentration <250 U/L were SCA, MCA, or MCAC (sensitivity 44%, specificity 98%) and, thus, virtually excluded PC. A carcinoembryonic antigen (CEA) <5 ng/mL suggested a SCA or PC (sensitivity 50%, specificity 95%). A CEA >800 ng/mL strongly suggested MCA or MCAC (sensitivity 48%, specificity 98%). A carbohydrate-associated antigen (CA) 19-9 <37 U/mL strongly suggested PC or SCA (sensitivity 19%, specificity 98%). Cytologic examination revealed malignant cells in 48% of MCAC (n = 111). DISCUSSION: Most pancreatic cystic tumors should be resected without the need for cyst fluid analysis. However, in asymptomatic patients, in patients with an increased surgical risk, and, in patients in whom there is a diagnostic uncertainty about the presence of a PC, cyst fluid analysis helps to determine the optimal therapeutic strategy.     

Endoscopic ultrasonography as additional preoperative workup is valuable in half of the patients with a pancreatic body or tail lesion

BackgroundThe management of pancreatic body and tail lesions is underexposed. It remains unclear whether endoscopic ultrasonography (EUS) increases the accuracy of the preoperative workup. This study assessed the diagnostic value and safety of EUS in addition to cross-sectional imaging in a surgical cohort of patients with pancreatic body or tail lesions.MethodsA multicenter retrospective cohort study was performed of patients who underwent distal pancreatectomy from 2010 to 2017. The composite primary outcome was the additional value of EUS, defined as: (a) EUS confirmed an uncertain diagnosis on cross-sectional imaging, (b) EUS was correct in case of discrepancy with cross-sectional imaging, or (c) EUS provided tissue diagnosis for neoadjuvant treatment. Furthermore, serious adverse events and needle tract seeding were assessed.ResultsIn total, 181 patients were included, of whom 123 (68%) underwent EUS besides cross-sectional imaging. Postoperative pathology was heterogeneous: 91 was malignant, 49 premalignant, 41 benign. Most lesions were solid (n = 117). EUS had additional value in 59/123 (48%) patients; 27/50 (54%) of cystic and 32/73 (44%) of solid lesions. No serious adverse event or needle tract seeding following EUS occurred.ConclusionEUS had additional value besides cross-sectional imaging in half of the patients and showed low associated risks.