Endoscopic Ultrasound-Guided Fine Needle Aspiration and Biopsy

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and biopsy (FNB) has been widely accepted as a fundamental procedure for the diagnosis and staging of lesions of the gastrointestinal tract or non-gastrointestinal lesions within reach of the aspiration needle. EUS-FNA has been used in lesions of the esophagus, mediastinal lesions, lymph node (LN) sampling, lung cancer diagnosis and other less common conditions (such as tuberculosis and sarcoidosis), gastrointestinal subepithelial lesions, pancreatic solid cystic lesions and neuroendocrine tumors, liver and bile duct lesions (such as cholangiocarcinoma and hepatocellular carcinoma), rectal and pelvic lesion, and lesions of extra-gastrointestinal organs (such as the adrenals and the prostate). Continued improvements in the technology and the technical aspects of EUS-guided FNA and FNB aim to improve the diagnostic accuracy and sensitivity and at the same time reduce the adverse events associated with the procedure. This chapter focuses on common technical aspects of EUS-FNA and FNB, such as the choice of needle and use of the stylet and suction, and performs a short review of the current applications of EUS-guided FNA in gastrointestinal and extra-intestinal lesions, along with a brief review of the adverse events that have been associated with the procedure.