Interventional endoscopic ultrasonography: Where are we headed?

Recent advances in endoscopic ultrasound-guided biliary drainage

Endoscopic ultrasound-guided biliary drainage (EUS-BD) is increasingly used as an alternative in patients with biliary obstruction who fail standard endoscopic retrograde cholangiopancreatography (ERCP). The two major endoscopic approach routes for EUS-BD are the transgastric intrahepatic and the transduodenal extrahepatic approaches. Biliary drainage can be achieved by three different methods, transluminal biliary stenting, transpapillary rendezvous technique, and antegrade biliary stenting. Choice of approach route and drainage method depends on individual anatomy, underlying disease, and location of the biliary stricture. Recent meta-analyses have revealed that cumulative technical success and adverse event rates were 90-94% and 16-23%, respectively. Development of new dedicated devices for EUS-BD would help refine the technical aspects and minimize the possibility of complications, making it a more promising procedure.

Intratumoral infection by CMV may change the tumor environment by directly interacting with tumor-associated macrophages to promote cancer immunity

Cytomegalovirus (CMV) is a herpesvirus that induces an extremely robust and sustained immune response. For this reason, CMV has been proposed as a vaccine vector to promote immunity to both pathogens and cancer. However, exploration of CMV as a vaccine vector is at an early stage and there are many questions. Using a mouse melanoma model, we recently found that a CMV-based vaccine induced large populations of melanoma-specific T cells, but was not effective at slowing tumor growth unless it was injected directly into the tumor. These surprising results have led us to hypothesize that CMV may be adept at modulating the tumor micro-environment through its infection of macrophages. Importantly, injection of CMV into the growing tumor synergized with blockade of the PD-1 checkpoint to clear well-established tumors. Here, we discuss our results in the context of CMV-based vaccines for pathogens and cancer.