Role of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for diagnosis of solid pancreatic masses.

Since it was developed in 1992, endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has been widely used and has been adapted for gastrointestinal and perigastrointestinal lesions. A medical literature review to evaluate the role of EUS-FNA for diagnosis of solid pancreatic masses showed a 78-95% sensitivity, 75-100% specificity, 98-100% positive predictive value, 46-80% negative predictive value and a 78-95% accuracy. The reported complication rates of EUS-FNA for pancreatic solid masses were 0-2%, although the criteria for complications varied among the studies. Because of its high diagnostic yield and low complication rate, EUS-FNA is cost-effective and widely applicable for the diagnosis of solid pancreatic masses, and is the best initial and the preferred secondary method compared with other biopsy techniques, such as endoscopic retrograde cholangiopancreatography-guided biopsy, computed tomography/ultrasound-FNA and surgery. Although EUS-FNA is 'a nearly perfected procedure,' controversy remains, such as the most suitable diameter of the needle, the appropriate number of needle passes and the necessity of on-site cytopathological evaluation. Recently investigators reported that using molecular analysis of EUS-FNA samples can achieve a higher diagnostic efficacy. Further research is encouraged to optimize the EUS-FNA procedure to reach its maximum diagnostic yield for solid pancreatic masses.