Endoscopic ultrasound-guided injection therapy for hepatobiliary disease

Endoscopic ultrasound (EUS)-guided injection therapy is the new frontier in the management of patients with hepatobiliary disease. Celiac plexus block/neurolysis was the first form of injection therapy and has been validated in many subsequent trials. Cyst ablation therapy, fiducial insertion, angiography, portal hypertensive therapy, endoscopic portosystemic shunt creation, portal vein embolization and injection of chemotherapeutic/biologic agents for antitumor therapy are more recent uses and will be discussed. Celiac plexus neurolysis is currently well established in providing adjunct pain control in patients with advanced malignancy. There are limited data available for its use in benign conditions. EUS-guided ablative therapy for pancreatic cysts remains an area for future research but seems to have a role for small thin-walled non-septated cysts. EUS-guided implantation of fiducials is technically feasible but its exact impact on tumor regression is unknown. Several case reports have documented EUS-guided alcohol and thrombin injection into pseudoaneurysms and cyanoacrylate and coil embolization for variceal therapy. Injection of viral vectors and immunomodulating cell cultures as antitumor therapy has been described but the evidence is still preliminary and further data are awaited.