Clinical outcome in patients with hilar malignant strictures type II Bismuth-Corlette treated by minimally invasive unilateral versus bilateral endoscopic biliary drainage.

Background: Stenting of malignant hilar strictures remains a standard endoscopic treatment in patients with unresectable tumors. The aim of this two-center prospective study was to compare unilateral versus bilateral drainage in hilar malignant stenosis Bismuth-Corlette type II.

Methods: During a 3-year period, a total of 49 patients with hilar tumors (Bismuth-Corlette type II) were referred for endoscopic treatment, following the criteria of unresectability. Ultrasound, computed tomography scan and magnetic resonance cholangiopancreatography (MRCP) were previously performed in all patients in order to facilitate endoscopic retrograde cholangiopancreatography (ERCP). The stricture was first passed by the hydrophilic guide-wire and then contrast medium was injected. Mechanical bile duct dilation was performed, followed by plastic stent placement only in the liver lobe which was previously opacified. The procedures were performed under conscious sedation. The patients were followed up for the next 12 months with a stent exchange every 3 months. Primary outcome was assessed by patient survival in the first 12 months after the procedure.

Results: All 49 patients were treated with ERCP while 39 (79.59%) had successful stent placement. Among these, 32 had hilar cholangiocarcinoma (82%) and 7 (18%) had gallbladder cancer. Two groups of patients had Bismuth II strictures: A, 21 patients (54%) with unilateral contrast injection and drainage, and B, 18 (46%) with bilateral contrast injection and drainage. A total of 57 plastic stents were used (10 Fr, 89%; 11.5 Fr, 11%). Group B showed a lower bilirubin level 7 days after the procedure (P=0.008). Early complications were cholangitis (3 patients, 2 in group A and 1 in group B) and acute pancreatitis (2 patients, 1 each in A and B) with no statistical difference between the groups. Late complications were stent migration (5 patients, 1 in A and 4 in B) and stent clogging (6 patients, 2 in A and 4 in B) showing a significant difference between the groups (P<0.01). The first stent replacement after 3 months was successful in 87% of patients (four died due to disease progression and one due to cardiopulmonary insufficiency) showing no statistical difference between the groups. At 6 months follow-up, 72% patients survived, with no statistical difference between the groups. A final follow-up (12 months) showed the survival rate of 18% (4 patients from group A and 3 from group B) (P>0.05).

Conclusions: A minimally invasive approach, based on the criterion that every bile duct being opacified needs to be drained, is associated with a lower incidence of early complications. Considering that the clinical outcome measured by bilirubin level was lower in patients with bilateral drainage 7 days after the procedure, we assumed that drainage of 50% or more of the liver volume leads to sufficient drainage effectiveness.