Endoscopic Ultrasound Elastography for Differential Diagnosis of Pancreatic Masses: A Meta-Analysis

Background

Distinguishing malignant from benign pancreatic tumors is challenging with current imaging techniques. Endoscopic ultrasound (EUS) elastography has further improved the efficacy of EUS for characterizing pancreatic lesions.

Aims

To assess, by combining data from existing trials, the accuracy of EUS elastography in diagnosing malignant tumors for patients with pancreatic masses.

Methods

All relevant studies published were identified by systematic searching of databases. A meta-analysis was performed using a random-effects model to combine study results.

Results

Seven studies involving 752 patients were included. The sensitivity of EUS elastography for differential diagnosis of solid pancreatic masses was 97 % (95 % CI, 0.95–0.98), and the specificity was 76 % (95 % CI, 0.69–0.82). The area under the curve under summary receiver operating characteristic (SROC) was 0.9529. The combined positive likelihood ratio was 3.71 (95 % CI, 2.72–5.07), and the negative likelihood ratio was 0.05 (95 % CI, 0.02–0.13).

Conclusion

Our meta-analysis shows that EUS elastography is a useful tool for differential diagnosis of solid pancreatic neoplasms with very high sensitivity and relatively low specificity. The results indicate that EUS elastography not only provides information complementary to that from EUS but also potentially increases the yield of fine needle aspiration and reduces the number of unnecessary biopsies.     

Endoscopic ultrasound elastography in the diagnosis of pancreatic masses: A meta-analysis

Background and aims

Endoscopic ultrasound (EUS) elastography is a novel non-invasive technique that can be used for distinguishing benign from malignant pancreatic masses. However, the studies have reported widely varied sensitivities and specificities. A meta-analysis was performed to assess the performance of EUS elastography for the differentiation of benign and malignant pancreatic masses.

Prospective cohort study comparing transient EUS guided elastography to EUS-FNA for the diagnosis of solid pancreatic mass lesions

BackgroundSemiquantitative EUS-elastography has been introduced to distinguish between malignant and benign pancreatic lesions. This study investigated whether semiquantitative EUS-guided transient real time elastography increases the diagnostic accuracy for solid pancreatic lesions compared to EUS-FNA.Patients and methodsThis single centre prospective cohort study included all patients with solitary pancreatic lesions on EUS during one year. Patients underwent EUS-FNA and semiquantitative EUS-elastography during the same session. EUS and elastography results were compared with final diagnosis which was made on the basis of tissue samples and long-term outcome.Results91 patients were recruited of which 68 had pancreatic malignancy, 17 showed benign disease and 6 had cystic lesions and were excluded from further analysis. Strain ratios from malignant lesions were significantly higher (24.00; 8.01–43.94 95% CI vs 44.00; 32.42–55.00 95% CI) and ROC analysis indicated optimal cut-off of 24.82 with resulting sensitivity, specificity and accuracy of 77%, 65% and 73% respectively. B-mode EUS and EUS-FNA had an accuracy for the correct diagnosis of malignant lesions of 87% and 85%. When lowering the cut-off strain ratio for elastography to 10 the sensitivity rose to 96% with specificity of 43% and accuracy of 84%, resulting in the least accurate EUS-based method. This was confirmed by pairwise comparison.ConclusionSemiquantitative EUS-elastography does not add substantial value to the EUS-based assessment of solid pancreatic lesions when compared to B-mode imaging.     

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.     

超声内镜弹性成像在良恶性胰腺病变鉴别中的应用价值

目的:探讨超声内镜弹性成像(endoscopic ultrasound,EUS)在胰腺占位病变良恶性鉴别中的应用价值.方法:影像学结果并经超声内镜检查确定有胰腺占位性病变的患者入选,对目标病变行超声内镜弹性成像检查,按照弹性成像5分法对组织弹性成像进行评分,将弹性成像评分为12分归为良性,3-5分归为恶性病变.结果:自2009-06/2011-06,共27例符合标准的胰腺占位病变患者入选,其中胰腺癌19例,超声内镜弹性成像评分3分(n=11)、4分(n=5)、5分(n=3),无功能性良性内分泌肿瘤(4分)及低度恶性神经内分泌肿瘤(5分)各1例,炎性病变6例,评分1分(n=1)、2分(n=3)、3分(n=2).超声内镜弹性成像对27例胰腺占位病变良恶性鉴别中24例诊断准确,诊断灵敏度100%,特异度57.14%,阳性预测值86.96%,阴性预测值100%.结论:超声内镜弹性成像对胰腺良恶性病变的鉴别具有较高的准确性,可望为疾病诊断提供新的影像学手段,但其仍为一种影像学手段,具有一定的局限性,并不替代胰腺的细胞病理学检查.     

Endoscopic ultrasound elastography for differentiating between pancreatic adenocarcinoma and inflammatory masses:A meta-analysis

AIM:To evaluate the accuracy of endoscopic ultrasound(EUS)elastography for differentiating between pancreatic ductal adenocarcinoma(PDAC)and pancreatic inflammatory masses(PIM).METHODS:Electronic databases(updated to December 2012)and manual bibliographical searches were carried out.A meta-analysis of all diagnostic clinical trials evaluating the accuracy of EUS elastography in differentiating PDAC from PIM was conducted.Heterogeneity was assessed among the studies.The metaanalysis was performed to evaluate the accuracy of EUS elastography in differentiating PDAC from PIM in homogeneous studies.RESULTS:Ten studies involving 781 patients were included in the analysis.Significant heterogeneity in sensitivity was observed among the studies(Cochran Q test=24.16,df=9,P=0.0041,I2=62.8%),while heterogeneity in specificity was not observed(Cochran Q test=5.93,df=9,P=0.7473,I2=0.0%).The area under the curve under the Sports Rights Owners Coalition was 0.8227.Evaluation of heterogeneity suggested that the different diagnostic standards used in the included studies were the source of heterogeneity.In studies using the color pattern as the diagnostic standard,the pooled sensitivity,specificity,positive likelihood ratio(LR),negative LR and diagnostic OR were0.99(0.97-1.00),0.76(0.67-0.83),3.36(2.39-4.72),0.03(0.01-0.07)and 129.96(47.02-359.16),respectively.In studies using the hue histogram as the diagnostic standard,the pooled sensitivity,specificity,positive LR,negative LR and diagnostic OR were 0.92(0.89-0.95),0.68(0.57-0.78),2.84(2.05-3.93),0.12(0.08-0.19)and 24.69(12.81-47.59),respectively.CONCLUSION:EUS elastography is a valuable method for the differential diagnosis between PDAC and PIM.And a preferable diagnostic standard should be explored and improvements in specificity are required.     

Endoscopic ultrasound-guided elastography in the nodal staging of oesophageal cancer

AIM: To assess quantitative endoscopic ultrasound (EUS)-guided elastography in the nodal staging of oesophago-gastric cancers.METHODS: This was a single tertiary centre study assessing 50 patients with established oesophago-gastric cancer undergoing EUS-guided fine needle aspiration biopsy (FNAB) of lymph nodes between July 2007 and July 2009. EUS-guided elastography of lymph nodes was performed before EUS-FNAB. Standard EUS characteristics were also described. Cytological determination of whether a lymph node was malignant or benign was used as the gold standard for this study. Comparisons of elastography and standard EUS characteristics were made between the cytologically benign and malignant nodes. The main outcome measure was the accuracy of elastography in differentiating between benign and malignant lymph nodes in oesophageal cancers.RESULTS: EUS elastography and FNAB were performed on 53 lymph nodes. Cytological malignancy was found in 23 nodes, one was indeterminate, one was found to be a gastrointestinal stromal tumor and 25 of the nodes were negative for malignancy. On 3 occasions insufficient material was obtained for analysis. The area under the curve for the receiver operating characteristic curve for elastography strain ratio was 0.87 (P < 0.0001). Elastography strain ratio had a sensitivity 83%, specificity 96%, positive predictive value 95%, and negative predictive value 86% for distinguishing between malignant and benign nodes. The overall accuracy of elastography strain ratio was 90%. Elastography was more sensitive and specific in determining malignant nodal disease than standard EUS criteria.CONCLUSION: EUS elastography is a promising modality that may complement standard EUS and help guide EUS-FNAB during staging of upper gastrointestinal tract cancer.     

Diagnostic performance of contrast-enhanced ultrasound for pancreatic neoplasms: A systematic review and meta-analysis

BackgroundEarly diagnosis of pancreatic cancer is essential to optimize treatment strategies.ObjectivesTo evaluate the diagnostic performance of contrast-enhanced ultrasound for benign and malignant pancreatic neoplasms.Data sourcesPubmed, Embase, Web of Science, and Cochrane Library databases.Study eligibility criteriaRetrospective or prospective studies.ParticipantsPatients with a confirmed diagnosis of benign and malignant pancreatic neoplasms.InterventionContrast-enhanced ultrasound.Study appraisal and synthesisPooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic risk ratio, and corresponding 95% confidence intervals; summary receiver operating characteristic (SROC) curve; a Fagan nomogram.ResultsTen studies involving 641 patients were included. Pooled sensitivity, specificity, and positive and negative predictive values were 91% (95% CI: 87%, 93%), 87% (95% CI: 78%, 93%), 7.2 (95% CI: 4.3, 12.3), and 0.11 (95% CI: 0.08, 0.15), respectively; and the odds ratio for diagnosis was 67 (95% CI: 34, 113). Contrast-enhanced ultrasound had good diagnostic ability and accuracy. Pre- and post-test probability of disease was 50% and 88%, respectively, when the positive likelihood ratio was 7.ConclusionContrast-enhanced ultrasound can be used for qualitative diagnosis of benign and malignant pancreatic neoplasms.Implications of key findingsCEUS should be considered as an important imaging tool for the characterization of pancreatic tumors.Systematic review registration numberCRD42017070434 (PROSPERO).     

超声内镜引导下细针穿刺活检对胰腺实性占位定性诊断价值的Meta分析

目的:系统评价超声内镜引导下细针穿刺活检(EUS-FNA)在胰腺实性占位定性诊断中的价值.方法:计算机检索MEDLINE、Cochrane Library、中国生物医学文献数据库、万方数据库、中国学术期刊全文等数据库,检索时间均为建库至2011-10.全面查找有关EUS-FNA诊断胰腺实性占位的文献,按照诊断试验的纳入标准筛选文献,提取纳入文献的特征信息(研究背景、设计信息和诊断参数信息),根据QUADAS质量评价标准纳入文献的质量.采用Meta-Disc1.4软件进行Meta分析,检验异质性,并根据异质性结果选择相应的效应模型.对纳入文献予以加权定量合并,计算汇总敏感度、特异度、阳性似然比、阴性似然比和诊断优势比及其95%CI,绘制汇总受试者工作特征(SROC)曲线,并计算曲线下面积(AUC).结果:共检索出相关文献280篇,按照文献纳入标准,最终纳入18篇文献(均为英文文献).EUS-FNA对胰腺实性占位定性诊断价值分别为:汇总敏感度为0.90[95%CI(0.89-0.92)],汇总特异度为0.95[95%CI(0.93-0.97)],汇总阳性似然比为13.56[95%CI(8.31-22.15)],汇总阴性似然比为0.12[95%CI(0.10-0.15)],汇总诊断优势比为143.62[95%CI(93.98-219.46)],SROC曲线下面积AUC为0.9711,Q*=0.9215.另外,本研究还对有无病理医生在场指导进行了亚组分析,发现有病理医生在场的AUC为0.9757,Q*=0.9295.且汇总诊断优势比173.37[95%CI(98.09-306.44)],明显较无病理医生在场的113.64[95%CI(60.22-214.46)]高.结论:经SROC曲线证实,EUS-FNA活检在胰腺实性占位定性诊断中具有较高的灵敏度和特异度,尤其是有病理医生在场指导的情况下,可作为临床上胰腺实性占位定性诊断的重要检查手段.     

Diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration for pancreatic cancer: A meta-analysis

Background and objectiveEUS-FNA of pancreatic lesion has been put into clinical use widely in many centers. The present meta-analysis was conducted to study the diagnostic role of EUS-FNA in pancreatic cancer.MethodsA comprehensive review of study on the precision of EUS-FNA in the diagnosis of pancreatic cancer. A random effects model was used to pool the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR) and diagnostic odds ratio (DOR). A summary receiver-operating characteristic (SROC) was constructed to summarize the overall test performance.ResultsThirty-one articles were eligible for the meta-analysis. The pooled sensitivity, specificity, PLR, NLR and DOR of EUS-FNA in the diagnosis of pancreatic cancer were 0.89 (95% CI: 0.88–0.90), 0.96 (95% CI: 0.95–0.97), 16.88 (95% CI: 10.63–26.79), 0.13 (95%CI: 0.10–0.16) and 150.80 (95%CI: 95.94–237.03) respectively. In subgroup meta-analysis of the prospective studies, the pooled sensitivity, specificity, PLR, NLR and DOR were 0.91 (95% CI: 0.90–0.93), 0.94 (95% CI: 0.91–0.96), 11.19 (95% CI: 6.36–19.69), 0.10 (95% CI: 0.07–0.15) and 125.22 (62.37–251.41). The area under the curve (AUC) was 0.97, indicating a good performance of overall accuracy.ConclusionEUS-FNA has the high sensitivity and specificity in differentiating pancreatic cancer. Moreover, it is also a safe diagnostic modality with little complications.     

Diagnostic yield of EUS-FNA-based cytology distinguishing malignant and benign IPMNs: A systematic review and meta-analysis

ObjectivesDifferential diagnosis of malignant and benign intraductal papillary mucinous neoplasms (IPMNs) is essential to determine the optimal treatment. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is currently used to diagnose pancreatic cystic lesions worldwide, but few studies have focused on the diagnostic yield to distinguish malignant and benign IPMNs. Therefore, we aim to systematically review the diagnostic yield of EUS-FNA-based cytology to distinguish malignant and benign IPMNs.MethodsRelevant studies with a reference standard of definitive surgical histology which published between 2002 and 2012 were identified via MEDLINE and SCOPUS. Malignant IPMNs included invasive adenocarcinoma, carcinoma in situ, and high-grade dysplasia.ResultsFour studies with 96 patients were included in this meta-analysis. For diagnostic yield of EUS-FNA-based cytology distinguishing malignant and benign IPMNs, the pooled sensitivity and specificity were 64.8% (95% CI, 0.44–0.82) and 90.6% (95% CI, 0.81–0.96), respectively. Similarly, the positive likelihood ratio and negative likelihood ratio were 6.35 (95% CI, 2.95–13.68) and 0.43 (95% CI, 0.14–1.34), respectively. Malignant IPMNs were observed in 20.8% (20/96) of patients in EUS-FNA studies.ConclusionsEUS-FNA-based cytology has good specificity but poor sensitivity in differentiating benign from malignant IPMNs. Newer techniques or markers are needed to improve diagnostic yield.     

Diagnostic accuracy of EUS for vascular invasion in pancreatic and periampullary cancers: a meta-analysis and systematic review

BACKGROUND: Vascular invasion (VI) in a patient with pancreatic or periampullary cancers precludes surgery and indicates a poor prognosis. Published data on the accuracy of EUS in diagnosing VI is varied. OBJECTIVE: The aim of this meta-analysis was to evaluate the accuracy of EUS in diagnosing VI in patients with pancreatic and periampullary cancers. DESIGN: Data from EUS studies were pooled according to the Mantel-Haenszel and DerSimonian Laird methods. PATIENTS: EUS studies in which VI was confirmed by surgery or angiography were selected. INTERVENTIONS: EUS. MAIN OUTCOME MEASURES: Pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratio of EUS. RESULTS: Data were extracted from 29 studies (N = 1308) that met the inclusion criteria. The pooled sensitivity of EUS in diagnosing VI was 73% (95% CI, 68.8-76.9) and the pooled specificity was 90.2% (95% CI, 87.9-92.2). The positive likelihood ratio for diagnosing VI by EUS was 9.1 (95% CI, 4.6-17.9) and the negative likelihood ratio was 0.3 (95% CI, 0.2-0.5). Diagnostic odds ratio, the odds of having VI in positive as compared with negative EUS studies, was 40.1 (95% CI, 16.1-99.9). The P value for chi(2) heterogeneity for all the pooled estimates was >.05. CONCLUSIONS: Although EUS is the best noninvasive test to diagnose VI in pancreatic and periampullary cancers, this meta-analysis showed that the specificity (90%) is high but the sensitivity (73%) is not as high as suggested. Further refinements in EUS technologies and interpretation may improve the sensitivity for detecting VI.     

Comparison of Diagnostic Accuracy of Real-Time Elastography and Shear Wave Elastography in Differentiation Malignant From Benign Thyroid Nodules

Thyroid nodules are relatively more prevalent in iodine-deficiency area, and the incidence increased sharply in the past decade in these areas. Workup of malignant from benign nodules in clinic was the main problem for managing thyroid nodules.An overall search for the articles about the diagnostic performance of real-time elastography (RTE) and shear wave elastography (SWE) before April 2015 in the databases of PubMed, Embase, and Google scholar. The pooled sensitivity, specificity, and summary receiver operating characteristic (SROC) curve were obtained from individual studies with a random-effects model. Subgroup and meta-regression analysis were also performed.Fifty-six studies involved in 2621 malignant nodules and 7380 benign nodules were contained in our meta-analysis. The pooled sensitivity and specificity of RTE was 83.0% and 81.2%, which is higher than SWE (sensitivity: 78.7%, specificity: 80.5%). The areas under the SROC curve of RTE and SWE were 0.885 and 0.842 respectively. RTE had higher diagnostic value for Caucasians than Asians. Stran ratio (SR) assessment had higher diagnostic performance than elasticity score (ES) system. Similarly, it had higher diagnostic value when malignant nodules were more than 50.In summary, the results revealed that RTE had higher diagnostic performance than SWE in differentiating malignant from benign nodules. However, future international multicenter studies in the region of thyroid risk need to further assess the diagnostic performance of RTE.     

~(18)F-脱氧葡萄糖-正电子发射/计算机体层扫描对肺部良恶性病变鉴别诊断价值的荟萃分析

目的 应用荟萃分析方法综合评价~(18)F-脱氧葡萄糖-正电子发射/计算机体层扫描(~(18)F-FDG PET/CT)对肺部良恶性病变的鉴别诊断价值.方法 应用"PET/CT&lung cancer"等检索词在PubMed等数据库检索1980-2008年发表的相关文献,根据纳入标准筛选符合条件的文献,并对文献进行信息统计、科学性评估及质量分级;采用Meta-Disc1.4和RewMan 4.2软件进行数据分析;通过汇总敏感度和特异度、汇总似然比及汇总受试者工作特征曲线(SROC曲线)等统计指标综合评价~(18)F-FDG PET/CT对肺部良恶性病变的鉴别诊断价值.结果 共纳入7篇文献,其中英文5篇,中文2篇,样本量为795例.异质性检验显示纳入研究齐性好,通过确定模型的汇总计算得出汇总敏感度为95%(93%～97%),汇总特异度为77%(71%～82%).汇总阳性似然比为4.12,汇总阴性似然比为0.08,SROC曲线下面积为94%.结论 ~(18)F-FDG PET/CT对肺部良恶性病变的鉴别诊断具有较大价值,但仍需要开展更大样本、多中心、高质量的前瞻性研究,以更准确地评价其临床价值.     

Role of Endoscopic Ultrasound Elastography Strain Histograms in the Evaluation of Patients with Pancreatic Masses

Background: The Endoscopic Ultrasound (EUS) quantitative elastography strain ratio (SR) and strain histogram (SH) methods for non-invasive pancreatic masses differentiation have been recently developed. The aim of this research was to investigate the accuracy of the diagnostic differentiation methods for patients with pancreatic masses, based on the EUS SR and SH.Methods: This is a prospective study involving 100 cases with pancreatic masses. Patients were classified into 2 groups: group that was diagnosed with pancreatic malignancy with positive histopathology by biopsy obtained by fine-needle aspiration or postoperative pathology (72 patients) and the group diagnosed with pancreatitis with negative pathology and follow-up for at least 1 year (28 patients).Results: Based on the ROC curve, the cut-off point for Mode 1 was set at 97. Values under it showed the presence of malignant pancreatic masses. Mode 1 achieved a sensitivity of 89% and a specificity of 43% with an overall accuracy of 76%. The predictive positive value was 70%, and the predictive negative value was 60%. The cut-off point for SR was set at 3.04, and the values were equal or above the suggested pancreatic malignancy. The SR achieved a sensitivity of 95.83%, a specificity of 61%, with an overall accuracy of 86%. The predictive positive and negative values were 86.2% and 85%, respectively.Conclusion: Mode 1 SH showed good sensitivity in the identification of pancreatic malignant tumors but were disappointingly of low specificity. Higher sensitivity, specificity, and overall accuracy were obtained by using the SR.     

Characterization of solid focal pancreatic lesions using endoscopic ultrasonography with real-time elastography

Abstract

Objectives. The aim of this study was to evaluate the diagnostic potential of strain assessment in solid focal pancreatic lesions using real-time elastography in combination with endoscopic ultrasonography (EUS). Material and methods. Forty-eight solid focal pancreatic lesions in 39 patients were included prospectively over a 3-year period and studied by EUS with real-time elastography (EUS-RTE). Lesions previously described as cystic by CT were not included. Distribution patterns of tissue strain were assessed using strain ratio (SR) measurements, continuous visual analog scale (VAS), and a visual categorical score (VCS), based on color coding of relative strain. Final diagnosis was based on histopathology, fine-needle aspiration cytology, and/or follow-up for ≥6 months. Results. The 48 lesions included 11 adenocarcinomas, 7 malignant neuroendocrine tumors (NETs), 11 benign or indeterminate NETs, 8 focal pancreatic lesions, 2 microcystic adenomas, and 9 other benign lesions. Malignant lesions had significantly higher median SR (7.05 vs. 1.56) and VAS scores (93.0 vs. 63.5) than benign lesions. A receiver operation characteristic curve analysis showed sensitivity of 67% and specificity of 71%, when using SR = 4.4 as a cut-off for malignancy. The highest SR values were found in two benign microcystic adenomas. Conclusions. EUS-RTE with SR measurements and VAS evaluation demonstrated a significant strain difference between benign and malignant lesions. However, the variation within the entities was substantial and some benign lesions presented with low strain. Benign lesions were generally characterized by a strain similar to reference tissue, whereas malignant lesions were harder. The recorded strain pattern in individual lesions must be interpreted with caution.     

正常胰腺及胰腺占位病变超声内镜弹性成像特点初步研究

目的 初步探讨正常胰腺及胰腺与位病变的超声内镜弹性成像特征及其在良恶性鉴别中的价值.方法 自2009年1月至6月,对9例胰腺占位病变行EUS的患者同时进行超声内镜实时弹性成像,同时选取6例因其他病变而行EUS者的正常胰腺行超声内镜实时弹性成像作对照,按照弹性成像5分法对组织弹性成像进行评分.结果 9例胰腺占位病变患者最终诊断为胰腺癌4例,囊腺癌1例,囊腺瘤2例,局限性胰腺炎2例,其弹性成像评分：胰腺癌1例3分、3例4分,囊腺癌5分,2例囊腺瘤均为2分,局限性胰腺炎2分和3分各1例;6例正常胰腺者其弹性成像评分1分5例,2分1例.当以1、2分为良性,3～5分为恶性病变的标准进行判断时,超声内镜弹性成像对9例胰腺占位性病变良恶性鉴别有8例准确.结论 胰腺良恶性组织弹性成像呈不同的图像特征,超声内镜实时弹性成像有助于胰腺良恶性病变的鉴别.     

New endoscopic ultrasound techniques for digestive tract diseases: A comprehensive review

Endoscopic ultrasound(EUS) is one of the most important modalities for the diagnosis of digestive tract diseases.EUS has been evolving ever since it was introduced.New techniques such as elastography and contrast enhancement have emerged, increasing the accuracy, sensitivity and specificity of EUS for the diagnosis of digestive tract diseases including pancreatic masses and lymphadenopathy.EUS-elastography evaluates tissue elasticity and therefore, can be used to differentiate various lesions.Contrast-enhanced EUS can distinguish benign from malignant pancreatic lesions and lymphadenopathy using the intravenous injection of contrast agents.This review discusses the principles and types of these new techniques, as well as their clinical applications and limitations.     

Endoscopic ultrasound elastography: current status and future perspectives

Elastography is a new ultrasound modality that provides images and measurements related to tissue stiffness. Endoscopic ultrasound(EUS) has played an important role in the diagnosis and management of numerous abdominal and mediastinal diseases. Elastography by means of EUS examination can assess the elasticity of tumors in the proximity of the digestive tract that are hard to reach with conventional transcutaneous ultrasound probes, such as pancreatic masses and mediastinal or abdominal lymph nodes, thus improving the diagnostic yield of the procedure. Results from previous studies have promised benefits for EUS elastography in the differential diagnosis of lymph nodes, as well as for assessing masses with pancreatic or gastrointestinal(GI) tract locations. It is important to mention that EUS elastography is not considered a modality that can replace biopsy. However, it may be a useful adjunct, improving the accuracy of EUSfine needle aspiration biopsy(EUS-FNAB) by selecting the most suspicious area to be targeted. Even more, it may be useful for guiding further clinical management when EUS-FNAB is negative or inconclusive. In the present paper we will discuss the current knowledge of EUS elastography, including the technical aspects, along with its applications in the differential diagnosis between benign and malignant solid pancreatic masses and lymph nodes, as well as its aid in the differentiation between normal pancreatic tissues and chronic pancreatitis. Moreover, the emergent indication and future perspectives are summarized, such as the benefit of EUS elastography in EUS-guided fine needle aspiration biopsy, and its uses for characterization of lesions in liver, biliary tract, adrenal glands and GI tract.     

小探头超声内镜诊断早期胃癌浸润深度准确性的Meta分析

目的对小探头超声内镜诊断早期胃癌浸润深度的准确性进行定量系统评价。 方法检索PubMed、Cochrane Library、Embase、CNKI、万方、维普数据库检索相关文献。对纳入的文献用Stata 14.2软件进行meta分析,得出汇总敏感度、特异度、阳性似然比、阴性似然比、诊断优势比及其95% CI,绘制总受试者工作特征曲线(SROC),并计算曲线下面积(AUC)等,评估其诊断价值。 结果共纳入文献16篇,包括3 168例病灶,汇总敏感度、特异度、阳性似然比、阴性似然比、诊断优势比及其95% CI分别是0.85(95% CI：0.78～0.90),0.73(95% CI：0.65～0.80),3.2(95% CI：2.4～4.1),0.20(95% CI：0.14～0.30),16(95% CI：9～26),SROC曲线下面积为0.85。 结论小探头超声内镜虽不能准确诊断早期胃癌M/SM1层浸润,但仍能很大程度提高对早期胃癌浸润深度的正确判断。