Primary EUS-GBD in Patients With Unresectable Malignant Biliary Obstruction and Cystic Duct Orifice Involvement.

Endoscopic biliary drainage with a self-expandable metal stent (SEMS) is an accepted form of palliative therapy for distal malignant biliary obstruction (MBO); it is a low invasive procedure with a long-term patency. Covered SEMSs have a longer patency than uncovered SEMSs in patients with MBO, because covered SEMSs can prevent tumor ingrowth. However, complications of covered SEMSs include stent occlusion, migration, kinking, non-occlusion cholangitis, liver abscess, pancreatitis and cholecystitis. Nonsurgical decompression of the gallbladder is urgently needs to prevent sepsis, perforation and death in patients with acute cholecystitis. Several risk factors of cholecystitis after SEMS placement for distal MBO have been reported: however, tumor involvement to the orifice of the cystic duct (OCD) is the major predictive factor for cholecystitis after endoscopic SEMSs placement for distal MBO palliative treatment . Acute cholecystitis related to SEMSs deployment was evaluated in 2009, by using endoscopic trans-papillary gallbladder drainage (TPGBD) in 11 individuals in whom SEMSs covered the OCD. None episode of cholecystitis was reported, however TPGBD is a difficult technique with a high rate of stent dislodgement and reintervention needed. EUS-GBD by using a lumen apposing metal stent have been proposed, but only for acute cholecystitis treatment or symptomatic gallbladder hydrops, never as a prophylactic technique. The aim of this study if to determine if primary prophylaxis EUS-GBD in patients with distal malignant biliary obstruction and the OCD involvement is superior than conservative management. Also, a cost-effectiveness analysis will be done in both arm groups. This would be the first trial to study the effect of prophylactic EUS-GBD prior SEMSs deployment in patients with distal malignant biliary obstruction.