Interventional endoscopic ultrasonography for pancreatic cancer

Endoscopic ultrasonography (EUS) represents the combination of endoscopy and intraluminal ultrasonography. This allows use of a high-frequency transducer (5-20 MHz) that, due to the short distance to the target lesion, provides ultrasonographic images of higher resolution than those obtained from other imaging modalities, including multiple-detector-row-computed tomography, magnetic resonance imaging, and positron emission tomography. EUS is now a widely accepted modality for diagnosing pancreatic diseases. However, the most important limitation of EUS has been the lack of specificity in differentiating between benign and malignant changes. In 1992, EUS-guided fine needle aspiration (FNA) of lesions in the pancreas head was introduced into clinical practice, using a curved linear-array echoendoscope. Since then, EUS has evolved from EUS imaging to EUS-FNA and wider applications. Interventional EUS for pancreatic cancer includes EUS-FNA, EUS-guided fine needle injection, EUS-guided biliary drainage and anastomosis, EUS-guided celiac neurolysis, radiofrequency ablation, brachytherapy, and delivery of a growing number of anti-tumor agents. This review focuses on interventional EUS, including EUS-FNA and therapeutic EUS for pancreatic cancer.