Original Article
Copyright ©2012 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Mar 7, 2012; 18(9): 889-895
Published online Mar 7, 2012. doi: 10.3748/wjg.v18.i9.889
Endoscopic ultrasound-guided elastography in the nodal staging of oesophageal cancer
Stuart Paterson, Fraser Duthie, Adrian J Stanley
Stuart Paterson, Department of Gastroenterology, Forth Valley Royal Hospital, Larbert FK5 4WR, United Kingdom
Fraser Duthie, Department of Pathology, Glasgow Royal Infirmary, Glasgow G4 0SF, United Kingdom
Adrian J Stanley, Department of Gastroenterology, Glasgow Royal Infirmary, Glasgow G4 0SF, United Kingdom
Author contributions: Stanley AJ and Paterson S were involved in study conception and design, performing endoscopic procedures, elastographic analysis and analysis of data; Paterson S wrote the manuscript which has been approved by both Duthie F and Stanley AJ; Duthie F provided cytological expertise and analysed specimens.
Correspondence to: Dr. Stuart Paterson, MB, ChB, MRCP, PhD, Department of Gastroenterology, Forth Valley Royal Hospital, Stirling Road, Larbert FK5 4WR, United Kingdom. stuart.paterson@nhs.net
Telephone: +44-1324-566842 Fax: +44-1786-434461
Received: August 5, 2011
Revised: October 16, 2011
Accepted: January 18, 2012
Published online: March 7, 2012
Abstract

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.

Keywords: Endoscopic ultrasound; Oesophageal cancer; Lymph nodes; Elastography; Tumour staging