Usefulness of Endoscopic Ultrasound-Guided Fine Needle Aspiration in the Diagnosis of Mediastinal Lesions

Abstract

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a safe and effective technique for the diagnosis of focal pancreatic lesions and enlarged abdominal lymph nodes. The aim of this study was to assess the usefulness of EUS-FNA in the diagnosis of mediastinal lesions. A retrospective review was performed of all consecutive cases in which EUS-FNA was used for the diagnosis of a mediastinal lesion between January 2001 and September 2003. We used a radial echoendoscope to assess the characteristics of the lesion and a linear-array echoendoscope to perform transesophageal needle aspiration with a 22-gauge needle. Histopathology of the resected specimen was considered as the gold standard in surgically treated patients whereas cytology obtained by EUS-FNA was the gold standard when surgery was not indicated. EUS-FNA was performed in 59 patients with a total of 89 lesions with mean (SD) dimensions of 2.4 (2.0) cm x 1.6 (1.4) cm. Malignant lesions were larger than benign ones (short axis, 2.7 [1.4] as compared with 1.0 [0.9] cm; P< .001). The diagnosis was obtained for 53 patients (90%) and 81 lesions (91%) with a mean of 2 (1) passes per lesion. The sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy of EUS-FNA were 81%, 100%, 100%, 75%, and 88%, respectively, when analyzed by lesion, and 88%, 100%, 100%, 80%, and 92% when analyzed by patient. EUS-FNA is an effective technique for the diagnosis of mediastinal lesions. The likelihood of malignancy increases with size.