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.     

乳腺癌超声弹性成像与组织学特征、分子生物学指标的相关性

目的探讨乳腺癌超声弹性成像与组织学特征、分子生物学指标的相关性。方法选择孕激素受体乳腺癌患者200例,采用超声弹性成像进行弹性评分;采用免疫组化法测定人表皮生长因子受体(Her)-2、雌激素受体(ER)和孕激素受体(PR)表达。观察超声弹性成像评分、组织学特征及Her-2、ER和PR表达阳性情况,超声弹性成像评分与组织学和分子生物学水平的关系。结果超声弹性成像评分中,评分3分9例、评分4分24例、评分5分167例。肿瘤大小≥2. 0 cm患者54例,浸润型导管癌患者168例,淋巴结转移患者73例。Her-2阳性表达患者125例,ER阳性表达患者139例,PR阳性表达患者145例。不同肿瘤大小超声弹性成像评分比较差异无统计学意义(P>0. 05);浸润型导管癌超声弹性成像评分5分多于浸润型小叶癌和其他,淋巴结转移超声弹性成像评分5分多于无淋巴结转移,Her-2阳性者超声弹性成像评分5分比例显著多于阴性者,ER阳性者超声弹性成像评分5分比例显著多于阴性者,PR阳性者超声弹性成像评分5分比例显著多于阴性者,差异有统计学意义(P<0. 05)。结论乳腺癌超声弹性成像与组织学病理及Her-2、ER和PR阳性表达具有一定相关性,二者联合可作为乳腺癌早期诊断及预后评估指标。     

联合应用超声内镜与超声微探头在早期食管癌术前分期中的作用

目的 探讨超声内镜联合超声微探头对早期食管浅表癌浸润深度和淋巴结转移的判断及其临床意义.方法 联合应用超声内镜和超声微探头对121例共124处早期浅表型食管癌病灶行临床分期,并与术后及黏膜切除后病理分期相比较.结果 内镜超声检查对早期食管癌术前T分期总的准确率为82.3%(102/124).本组早期食管癌淋巴结总的转移率为5.0%(6/121),其中原位无一例淋巴结转移,黏膜内癌淋巴结转移率为1.3%(1/78),黏膜下癌淋巴结转移率为11.6%(5/43).结论 联合使用超声内镜及超声微探头对早期食管癌可以进行准确的分期,可以指导早期食管癌治疗策略的选择.     

超声弹性成像在甲状腺癌颈部淋巴结转移诊断的应用

目的探讨甲状腺癌颈部淋巴结转移的超声弹性成像的诊断价值。方法经手术病理证实的有颈部淋巴结转移的50例甲状腺癌患者,手术切除转移性淋巴结114枚,无转移的淋巴结52枚,术前分别对以上淋巴结行常规超声检查及超声弹性成像检查,比较两组淋巴结的超声检查特点。结果颈部转移淋巴结多表现为长径/短径2、形态不规则、血流信号丰富、内部回声不均匀、微钙化等。常规超声的灵敏度71.45%、阴性预测值69.65%,低于实时弹性超声93.31%、91.54%,差异具有统计学意义(P0.05)。结论超声弹性成像技术有助于诊断甲状腺颈部淋巴结转移。     

超声弹性成像对乳腺良恶性病变的鉴别诊断价值分析

目的 探讨超声弹性成像对乳腺良恶性病变的鉴别诊断价值.方法 应用超声弹性成像技术对经手术病理学或穿刺组织活检确诊为乳腺肿块的乳腺疾病患者128例进行超声检查,以病理检查结果 作为"金标准",分析超声弹性对乳腺良恶性病变诊断的灵敏度、特异度、准确性、阳性预测值、阴性预测值,并测算弹性成像及灰阶声像图下病灶的长径及面积,测算长径变化率及面积比.结果 超声弹性成像诊断乳腺良恶性病变的敏感度为85.96%,特异度为95.77%,准确率为91.41%,阳性预测值为94.23%,阴性预测值为89.47%;病灶恶性组≥4分的占比为38.28%(49/128),显著高于良性组的2.34%(3/128) (P<0.05);乳腺恶性病灶在灰阶成像及弹性成像中长径、面积测值差异有统计学意义(P<0.05),良性病灶在灰阶成像及弹性成像中长径、面积测值差异不显著(P>0.05),良、恶性组间灰阶成像和弹性成像中的长径变化率、面积比差异有统计学意义(P<0.05).结论 超声弹性成像可以较为准确的判定乳腺肿物的相对弹性硬度,直径变化率及面积比等定量参数对肿物良恶性鉴别具有辅助功能.     

支气管镜超声弹性成像在肺门纵隔淋巴结良恶性的诊断价值

目的 探讨经支气管镜实时超声弹性成像鉴别肺门纵隔淋巴结性质的诊断价值.方法 经支气管镜超声弹性成像评价肺门纵隔淋巴结性质,并对该淋巴结行针吸活检术.弹性成像评分为1～4分.l、2分为阴性淋巴结,3、4分为阳性淋巴结.结果 纳入29例患者共43枚淋巴结.不同弹性分级组间良恶性构成比差异有统计学意义(X2＝16.92,P=0.001).弹性成像对恶性淋巴结的敏感度、特异度、准确度分别为70.83％、84.21％、76.74％.结论 经支气管镜实时超声弹性成像的敏感度、特异度、准确度高,有助于肺门纵隔淋巴结良恶性的鉴别诊断.     

内镜超声引导下细针穿刺抽吸术在纵隔病变诊断中的应用

目的 初步探讨内镜超声引导下细针穿刺抽吸术(EUS-FNA)在纵隔肿大淋巴结、纵隔不明原因占位定性诊断及肺癌N分期中的应用价值.方法 应用22 G穿刺针对61例患者经食管行EUS.FNA,穿刺物均行病理及细胞学检查.结果 EUS·FNA诊断阳性率为93.4%(57/61),细胞学及病理诊断阳性率分别为85.2%(52/61)和83.6%(51/61).100.0%(26/26)临床疑诊肺癌纵隔淋巴结转移而经支气管镜等检查未能提供病理或细胞学证据者均通过EUS-FNA得到诊断,其中21例诊断为肺癌、5例排除肺癌诊断为良性疾病;86.4%(19/22)纵隔不明原因占位明确定性;85.7%(6/7)有恶性肿瘤病史影像学检查疑诊纵隔淋巴结转移者,EUS-FNA病理及细胞学结果 支持转移;6例经支气管镜检查已获得明确病理细胞学诊断的肺癌病例但影像学提示纵隔淋巴结肿大,为明确N分期行EUS-FNA,结果 均为阳性,改变了原计划治疗方案.本组无一例EUS-FNA相关并发症发生.结论 对于明确纵隔肿大淋巴结、纵隔不明原因占位定性诊断及肺癌N分期,EUS-FNA是一种较为安全、有效的诊断方法.     

超声内镜引导下细针穿刺在消化系占位性病变诊断中的价值

目的 探讨超声内镜引导下的细针穿刺检查(EUS-FNA)在消化系占位性病变诊断中的价值.方法 2007年5月-2008年12月对68例患者行超声内镜检查及超声内镜引导下的细针穿刺检查,对比细胞学和(或)病理学检查结果与术后病理结果及随访结果.结果 EUS-FNA细胞取材成功率91.18%(62/68).其中病灶位于食管4例(6.45%,4/62),胃19例(30.65%,19/62),直肠19例(30.65%,19/62),肝脏3例(4.84%,3/62),纵隔4例(6.45%,4/62),淋巴结13例(20.97%,13/62).40例患者细胞学检查结果阳性,阳性率为64.52%(40/62).22例患者获得组织碎片或细条行病理学检查,组织获得率为35.48%(22/62),其中10例病理学检查结果阳性,阳性率为45.45%(10/22).与术后病理结果及长期随访结果对照,EUS-FNA对消化系占位性病变诊断的准确率为85.48%.敏感度为90.91%,特异度为100.00%,阴性预测值为57.14%,阳性预测值为100.00%.结论 在消化系占位性病变诊断中,EUS-FNA是一项安全、有效、准确的诊断及鉴别诊断方法,在细胞学诊断中具有重要临床价值.     

胰头癌淋巴结微转移的检出及其分析

目的 通过对胰头癌切除标本中淋巴结微转移的检测,分析淋巴结微转移对胰头痛临床分期及预后的影响,探讨其临床价值.方法 以手术显微镜法完整取出20例冈胰头癌行区域性胰十二指肠切除术标本中的淋巴结,常规病理检测淋巴结转移,免疫组化检测淋巴结微转移.结果 20例标本中共找到677枚淋巴结,常规病理显示13例共87枚淋巴结发生转移.在病理检测阴性的590枚淋巴结中,免疫组化检测又发现3例57枚淋巴结存在微转移.常规病理结合免疫组化检测,淋巴结转移阳性患者从65%(13/20)增加到80%(16/20);转移淋巴结的检出率从12.9%(87/677)上升到21.3%(144/677),相差显著(P<0.05).微转移检测使3例ⅡA期患者转为ⅡB期,有淋巴结微转移患者的1年内肿瘤转移、复发率为75%,而无微转移者的转移、复发率为25%.结论 胰头癌淋巴结微转移的检出有助于肿瘤分期的确定和预后的判断.     

组织谐波显像下BI-RADS分级的定量评分联合超声弹性成像评分诊断乳腺良恶性病灶的价值

目的探讨组织谐波显像下BI-RADS分级定量评分联合超声弹性成像评分诊断乳腺良恶性病灶的价值。方法在组织谐波显像条件下分析363个经病理证实的乳腺病灶的10项超声特征,并对其进行赋分,给予超声BI-RADS综合评分及分级,再行弹性成像评分(以罗葆明改良5分法为标准),以病理结果为金标准,比较BI-RADS定量评分、弹性成像以及两者联合诊断乳腺病灶良恶性的准确率。结果 (1)以病理诊断为金标准,将肿块综合评分定为15分,即BI-RADS4b级作为诊断乳腺肿块良恶性的界点分值,其诊断灵敏度为80.3%,特异性为95.4%,阳性预测值为89.9%,阴性预测值为90.6%,准确率为90.3%,约登指数为0.76。(2)以病理诊断为金标准,将弹性成像评分≤3分定为良性,≥4分为恶性时,其诊断灵敏度为77.0%,特异性为91.7%,阳性预测值为82.5%,阴性预测值为88.8%,准确率为86.8%,约登指数为0.69。联合诊断准确率高于综合评分及弹性成像评分单独诊断。结论以超声诊断指标综合评分为量化依据对乳腺病灶进行BI-RADS分级诊断,可以使超声报告在一定程度上更客观及规范化,同时联合弹性成像进行判断可为临床评价乳腺病灶恶性风险程度提供更可靠的依据。     

超声支气管镜下弹性成像技术在纵隔淋巴结性质判定中的价值

目的探讨超声支气管镜下弹性成像技术单独及联合胸部CT、常规超声在气管周围的纵隔及肺门淋巴结性质判定中的价值。 方法选取2016年6月至2018年3月期间在南京医科大学附属南京医院呼吸内科气管镜室拟行EBUS-TBNA检查的患者。记录目标淋巴结的胸部CT、常规超声及超声弹性成像各参数,根据EBUS-TBNA的病理阳性结果或者阴性结果进行一年的随访作为诊断的金标准。构建各个特征参数的受试者工作特征曲线,得到曲线下面积和最佳截断值,并计算出最佳截断值时各个参数的诊断准确率、灵敏度、特异度、阳性预测值、阴性预测值等指标。 结果共入组78例患者,117枚淋巴结：①胸部CT在判定淋巴结性质中,淋巴结短径≥10 mm,边界清楚,质地不均匀这三个特征具有统计学意义(P<0.05),其中质地不均匀的AUC最高,为0.711;②常规超声判定淋巴结性质时,淋巴结短径≥10 mm,边界清楚,低回声,形状呈类圆形这四个特征具有统计学意义(P<0.05),其中边界清楚的AUC最高,为0.655;③超声弹性成像图像应用图像类型、超声弹性评分、应变率比值以及蓝色面积比四种方法判断淋巴结性质,AUC分别是0.843,0.820,0.717,0.877;其中蓝色面积比的AUC最高;④联合胸部CT的淋巴结质地不均匀,常规超声的淋巴结边界清楚以及超声弹性成像的图像类型进行统计分析,得出准确率、灵敏度、特异度、阳性预测值、阴性预测值分别是85.5%,85.7%,87.9%,100%,100%,AUC为0.932。 结论超声弹性成像对于肺门及纵隔淋巴结的性质判断的诊断价值高于胸部CT及常规超声。三者联合能够明显提高淋巴结的恶性检出率。     

Differentiation of benign and malignant lymph nodes with contrast-enhanced echolymphography using endoscopic ultrasound-guided puncture

BACKGROUND/AIMS: Although endoscopic ultrasonography is considered the most useful diagnostic modality for the regional staging, the capability of diagnosing lymph node metastasis based on endoscopic ultrasonography images alone is not sufficient. To improve the capability of differential diagnosis of lymph node enlargement, contrast-enhanced echolymphography was performed using endoscopic ultrasonography-guided puncture. METHODOLOGY: Contrast-enhanced echolymphography was performed in 8 metastatic lymph nodes surgically resected from patients with gastrointestinal cancers (in vitro study) and also in 55 patients in whom abdominal lymph node swelling was indicated by endoscopic ultrasonography (in vivo study). Lymph nodes were punctured under real-time endoscopic ultrasonography guidance, and carbon dioxide microbubbles were injected to evaluate echo features before and after microbubbles injection. RESULTS: Contrast-enhanced echolymphography of freshly resected metastatic lymph nodes showed nonhomogeneous echo patterns. In regions demonstrating filling defects detected by contrast-enhanced echolymphography, neoplastic infiltration was pathologically observed. In almost all of the malignant lymph nodes studied in vivo, filling defects and heterogeneous enhancements were observed by contrast-enhanced echolymphography. However, contrast-enhanced echolymphography demonstrated uniform patterns in most of the benign group. The sensitivity, specificity, positive and negative predictive value, and accuracy of differential diagnosis by contrast-enhanced echolymphography were 95.8%, 90.3%, 88.5%, 96.6%, and 92.7%, respectively. CONCLUSIONS: Contrast-enhanced echolymphography is a useful method for help in the differentiation between reactive and malignant alterations of lymph nodes.     

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.     

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.     

Accuracy of endoscopic ultrasound-guided tissue acquisition in the evaluation of lymph nodes enlargement in the absence of on-site pathologist

AIM To evaluate factors that influence the diagnostic accuracy of endoscopic ultrasound(EUS)-guided tissue acquisition for lymph node enlargement in the absence of an on-site pathologist. METHODS A retrospective analysis of patients who underwent EUS-guided tissue acquisition for the pathological diagnosis of lymph node enlargement between April2012 and June 2015 is reported. Tissue acquisition was performed with both cytology and biopsy needles of different calibers. The variables evaluated were lymph node location and size, number of passes and type of needle used. Final diagnosis was based on surgical histopathology or, in non-operated cases, on EUSguided tissue acquisition and imaging assessment with a minimum clinical follow-up of 6 mo. RESULTS During the study period, 168 lymph nodes with a median size of 20.3 mm(range 12.5-27) were sampled from 152 patients. Ninety lymph nodes(53.6%) were located at mediastinum, and 105(62.5%) were acquired with biopsy needles. The final diagnosis was benign/reactive origin in 87 cases(51.8%), malignant in 65 cases(38.7%), and lymphoma in 16 cases(9.5%). The sensitivity, specificity, positive predictive value and negative predictive value for the detection of malignancy were 74.1%, 100%, 100% and 80.6%, respectively. The overall accuracy was 87.5%(95%CI: 81.7-91.7). No variables were independently associated with a correct final diagnosis according to the multivariate analysis. CONCLUSION EUS-guided tissue acquisition is a highly accurate technique for assessing lymph node enlargement. None of the variables evaluated were associated with diagnostic accuracy.     

Assessment for diagnosis of lymph node metastasis in esophageal cancer using endoscopic ultrasound elastography

Background

We performed endoscopic ultrasound real-time tissue elastography to more accurately diagnose lymph node metastasis of esophageal cancer. The aim of this study was to evaluate the ability of EUS elastography to distinguish benign from malignant lymph nodes in esophageal cancer patients.

Methods

The present study had two steps. As the first step (study 1), we developed diagnostic criteria for metastatic lymph nodes using elastography and verified the validity of the criteria. Three hundred and twenty-two lymph nodes from 35 patients treated by surgical resection were included in the study. As the second step (study 2), we preoperatively examined the lymph nodes of esophageal cancer patients with EUS elastography and compared its diagnostic performance with that of the conventional B-mode EUS images. A total of 115 lymph nodes from 31 patients were included.

Results

In study 1, lymph nodes were considered malignant if 50 % or more of the node appeared blue, or if the peripheral part of the lesion was blue and the central part was red/yellow/green. The sensitivity and specificity of the elastography were 79.7 and 97.6 % with an accuracy of 93.8 %, which was significantly higher than the values for conventional B-mode imaging. In study 2, the sensitivity and specificity of the EUS elastography were 91.2 and 94.5 % with an accuracy of 93.9 %, which was also significantly higher than the values for conventional B-mode EUS imaging.

Conclusions

The present study demonstrated that EUS elastography is useful for diagnosing lymph node metastasis of esophageal cancer.

     

Dynamic analysis of EUS used for the differentiation of benign and malignant lymph nodes

BACKGROUND: EUS elastography was reported to offer supplemental information that allows a better characterization of tissue, and that might enhance conventional EUS imaging. OBJECTIVE: Our purpose was to apply real-time elastography during EUS examinations and to assess the accuracy of the differentiation of benign versus malignant lymph nodes. DESIGN: Prospective cross-sectional feasibility study. SETTING: Department of Surgical Gastroenterology, Gentofte University Hospital, Hellerup, Denmark. PATIENTS: Patients diagnosed by EUS with cervical, mediastinal, or abdominal lymph nodes were included, with a total number of 78 lymph nodes examined. The final diagnosis of the type of lymph node was obtained by EUS-FNA cytologic analysis or by surgical pathologic examination and by a minimum 6 months of follow-up. INTERVENTIONS: Hue histogram analysis of the average images computed from EUS elastography movies was used to assess the color information inside the region of interest and to consequently differentiate benign and malignant lymph nodes. MAIN OUTCOME MEASUREMENTS: Differentiate between malignant and benign lymph nodes. RESULTS: By using mean hue histogram values, the sensitivity, specificity, and accuracy for the differential diagnosis were 85.4%, 91.9%, and 88.5%, respectively, on the basis of a cutoff level of 166 (middle of green-blue rainbow scale). The proposed method might be useful to avoid color perception errors, moving artifacts, or possible selection bias induced by analysis of still images. LIMITATIONS: Lack of the surgical standard in all cases. CONCLUSIONS: Computer-enhanced dynamic analysis based on hue histograms of the EUS elastography movies represents a promising method that allows the differential diagnosis of benign and malignant lymph nodes, offering complementary information added to conventional EUS imaging.     

A comparison of the accuracy of echo features during endoscopic ultrasound (EUS) and EUS-guided fine-needle aspiration for diagnosis of malignant lymph node invasion

Background: The purpose of this study was to re-evaluate echo features of lymph nodes during endoscopic ultrasound and assess the utility of these echo features and endoscopic ultrasound–guided fine-needle aspiration in predicting malignant lymph node invasion. Methods: Thirty-five lymph nodes in 25 patients with lung, esophageal, and pancreatic cancer were evaluated by endoscopic ultrasound. Endoscopic ultrasound examinations were performed with a radial scanning echoendoscope. Confirmation of benign lymph nodes was obtained by surgical resection while malignant lymph nodes were confirmed by real-time endoscopic ultrasound–guided fine-needle aspiration with a linear array echoendoscope. Results: Nineteen benign lymph nodes and 16 malignant lymph nodes in the mediastinum, celiac axis, and the peripancreatic area were included in the study. The following echo features were compared between benign and malignant lymph nodes: size greater than 1 cm, hypoechoic, distinct margins, and round shape. No single feature independently predicted malignant invasion. When all four of the above features were present in the same lymph node, the accuracy for predicting malignant invasion was 80%. However, all four features of malignant involvement were present in only 25% (4 of 16) of malignant lymph nodes. Our study also suggests that the above echo features may be a less reliable predictor of malignant invasion in pulmonary malignancies when compared to gastrointestinal cancers. Endoscopic ultrasound–guided fine-needle aspiration of lymph nodes in 22 patients revealed malignant lymph node invasion in 16 and benign cells in 6 patients. Conclusion: Endoscopic ultrasound–guided fine-needle aspiration is an important adjunct for accurate lymph node assessment for malignancy. (Gastrointest Endosc 1997;45:474-9.)