Retrospective Cohort Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 28, 2016; 22(12): 3381-3391
Published online Mar 28, 2016. doi: 10.3748/wjg.v22.i12.3381
Contrast-enhanced harmonic endoscopic ultrasonography for assessment of lymph node metastases in pancreatobiliary carcinoma
Takeshi Miyata, Masayuki Kitano, Shunsuke Omoto, Kumpei Kadosaka, Ken Kamata, Hajime Imai, Hiroki Sakamoto, Naoshi Nisida, Yogesh Harwani, Takamichi Murakami, Yoshifumi Takeyama, Yasutaka Chiba, Masatoshi Kudo
Takeshi Miyata, Masayuki Kitano, Shunsuke Omoto, Kumpei Kadosaka, Ken Kamata, Hajime Imai, Hiroki Sakamoto, Naoshi Nisida, Yogesh Harwani, Masatoshi Kudo, Department of Gastroenterology and Hepatology, Kinki University Faculty of Medicine, Osaka-sayama 589-8511, Japan
Takamichi Murakami, Department of Radiology, Kinki University Faculty of Medicine, Osaka-sayama 589-8511, Japan
Yoshifumi Takeyama, Department of Surgery, Kinki University Faculty of Medicine, Osaka-sayama 589-8511, Japan
Yasutaka Chiba, Division of Biostatistics, Clinical Research Center, Kinki University Faculty of Medicine, Osaka-sayama 589-8511, Japan
Author contributions: Miyata T wrote the manuscript; Miyata T, Kitano M, Imai H, Sakamoto H and Kudo M drafted the study conception and design; Miyata T, Kadosaka K, Harwani Y, Murakami T and Takeyama Y critically revised the article for important intellectual content; Kitano M and Sakamoto H performed the endosonography studies; Omoto S, Kamata K, Nisida N and Takeyama Y performed the pathological evaluations; Kadosaka K and Chiba Y provided statistical analysis; Imai H, Murakami T and Kudo M read images; and Harwani Y critically revised English grammar.
Supported by Grants from the Japan Society for the Promotion of Science and the Japanese Foundation for the Research and Promotion of Endoscopy, No. 22590764 and No. 25461035.
Institutional review board statement: This study was approved by the Institutional Review Board of Kinki University Faculty of Medicine.
Informed consent statement: All patients provided informed consent with regard to the procedures and participation in the study.
Conflict-of-interest statement: We wish to confirm that there are no known conflicts of interest associated with this publication.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Masayuki Kitano, MD, PhD, Department of Gastroenterology and Hepatology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-sayama 589-8511, Japan. m-kitano@med.kindai.ac.jp
Received: September 9, 2015
Peer-review started: September 16, 2015
First decision: October 14, 2015
Revised: October 23, 2015
Accepted: December 12, 2015
Article in press: December 14, 2015
Published online: March 28, 2016
Processing time: 195 Days and 18.9 Hours
Abstract

AIM: To assess the usefulness of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for lymph node metastasis in pancreatobiliary carcinoma.

METHODS: All patients suspected of pancreatobiliary carcinoma with visible lymph nodes after standard EUS between June, 2009 and January, 2012 were enrolled. In the primary analysis, patients with successful EUS-fine needle aspiration (FNA) were included. The lymph nodes were assessed by several standard EUS variables (short and long axis lengths, shape, edge characteristic and echogenicity), color Doppler EUS variable [central intranodal blood vessel (CIV) presence] and CH-EUS variable (heterogeneous/homogeneous enhancement patterns). The diagnostic accuracy relative to EUS-FNA was calculated. In the second analysis, N-stage diagnostic accuracy of CH-EUS was compared with EUS-FNA in patients who underwent surgical resection.

RESULTS: One hundred and nine patients (143 lymph nodes) fulfilled the criteria. The short axis cut-off ≥ 13 mm predicted malignancy with a sensitivity and specificity of 72% and 85%, respectively. These values were 72% and 63% for the long axis cut-off ≥ 20 mm, 62% and 75% for the round shape variable, 81% and 30% for the sharp edge variable, 66% and 61% for the hypoechogenicity variable, 70% and 72% for the CIV-absent variable, and 83% and 91% for the heterogeneous CH-EUS-enhancement variable, respectively. CH-EUS was more accurate than standard and color Doppler EUS, except the short axis cut-off. Notably, three patients excluded because of EUS-FNA failure were correctly N-staged by CH-EUS.

CONCLUSION: CH-EUS complements standard and color Doppler EUS and EUS-FNA for assessment of lymph node metastases.

Keywords: Contrast-enhanced harmonic endoscopic ultrasonography; Sensitivity and specificity; Lymph node; Pancreatobiliary carcinoma; Endoscopic ultrasonography-fine needle aspiration

Core tip: Diagnosis of malignant intra-abdominal lymph nodes is often challenging for endoscopists and radiologists. In the present study, the diagnostic accuracy for differentiating malignant from benign lymph nodes of standard endoscopic ultrasonography (EUS), color Doppler EUS, and contrast-enhanced harmonic (CH)-EUS relative to EUS-fine needle aspiration (FNA) was assessed. A secondary objective of the present study was to assess the N-stage diagnostic accuracy of CH-EUS and EUS-FNA in patients who underwent surgical resection. In conclusion, CH-EUS was more accurate than standard and color Doppler EUS, except the short axis cut-off. Notably, three patients excluded because of EUS-FNA failure were correctly N-staged by CH-EUS.