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

Backgrounds 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 aspi ration in predicting malignant lymph node invasion. Methods: Thirty-fi ve lymph nodes in 25 patients with lung, esophageal, and pancreatic ca ncer were evaluated by endoscopic ultrasound. Endoscopic ultrasound ex aminations were performed with a radial scanning echoendoscope. Confir mation of benign lymph nodes was obtained by surgical resection while malignant lymph nodes were confirmed by real-time endoscopic ultrasoun d-guided fine-needle aspiration with a linear array echoendoscope. Res ults: 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 a nd malignant lymph nodes: size greater than 1 cm, hypoechoic, distinct margins, and round shape. No single feature independently predicted m alignant invasion. When all four of the above features were present in the same lymph node, the accuracy for predicting malignant invasion w as 80%. However, all four features of malignant involvement were prese nt in only 25% (4 of 16) of malignant lymph nodes. Our study also sugg ests that the above echo features may be a less reliable predictor of malignant invasion in pulmonary malignancies when compared to gastroin testinal cancers, Endoscopic ultrasound-guided fine-needle aspiration of lymph nodes in 22 patients revealed malignant lymph node invasion i n 16 and benign cells in 6 patients. Conclusion: Endoscopic ultrasound -guided fine-needle aspiration is an important adjunct for accurate ly mph node assessment for malignancy.