Endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB): past, present, and future

Endoscopic ultrasound (EUS) is a combination of endoscopy and intraluminal ultrasonography. EUS also enables ultrasonographic images of high resolution to be obtained. However, whether a lesion is malignant or benign cannot be diagnosed solely from the findings of EUS. Endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) was developed to enhance the diagnostic capabilities of EUS by providing additional pathological findings. Though more than 10 years have passed since EUS-FNAB was first used for pancreatic disease, EUS FNAB has not been widely accepted in Japan. This may be due to the technical difficulties, relatively low sensitivity for the detection of malignancies, and Japanese gastroenterologists' and surgeons' inherent conservative way of thinking. We describe here a short history of EUS-FNAB, with details of technical tips, current indications and contraindications, diagnostic accuracy, and complications. The clinical utility of EUS-FNAB has been gradually understood and EUS-FNAB procedures have been increasing in number in Japan. So in the near future, EUS followed by EUS-FNAB will be routinely performed in the same manner as gastrointestinal endoscopy, followed by biopsy under direct vision. Also, therapeutic EUS procedures, such as EUS-guided celiac plexus neurolysis, pancreatic tumor ablation, drainage of pancreatic pseudocysts, and the development of an anastomosis may become feasible as less invasive and safer techniques than those used at present.