Efficacy and safety of preoperative biliary drainage in patients with Hilar Cholangiocarcinoma: a systematic review and meta-analysis.

Background: Preoperative biliary drainage (PBD) has been proposed as a strategy to manage the complications associated with biliary obstruction in hilar cholangiocarcinoma patients. However, the efficacy and safety of PBD in remain controversial, even in clinical guidelines. This meta-analysis aimed to provide a comprehensive evaluation of the efficacy and safety of PBD in patients with hilar cholangiocarcinoma.

Methods: PubMed, Medline, EMBASE, Cochrane Library, and registers were screened to investigate the efficacy and safety of PBD in patients with hilar cholangiocarcinoma. The search timeframe was set before December 2024. Mortality, morbidity, and postoperative infection served as the primary outcomes, while the secondary outcomes included transfusion, operative time, operative bloody loss, intraabdominal abscess, intraabdominal bleeding, leakage (bile leak or anastomotic leakage), hepatic insufficiency, renal insufficiency, second laparotomy, total hospital stay, cholangitis. Studies were evaluated for quality by Newcastle-Ottawa scale. Data were pooled as odds ratio ( OR ) or standard mean difference ( SMD ).

Results: Our meta-analysis of 21 studies (3059 patients) showed that PBD reduced hepatic insufficiency ( OR  = 0.38, 95% CI  = 0.16-0.90, P  = 0.03, I 2  = 69%) but increased risks of long term follow up mortality ( OR  = 1.90, 95% CI  = 1.02-3.56, P  = 0.04, I 2  = 0%), morbidity ( OR  = 1.47, 95% CI  = 1.12-1.92, P  = 0.01, I 2  = 52%), postoperative infection ( OR  = 2.46, 95% CI  = 1.17-5.18, P  = 0.02, I 2  = 69%), transfusion ( OR  = 1.39, 95% CI  = 1.06-1.81, P  = 0.02, I 2  = 49%), leakage ( OR  = 1.67, 95% CI  = 1.08-2.60, P  = 0.02, I 2  = 44%), cholangitis ( OR  = 6.40, 95% CI  = 1.75-23.48, P  = 0.01, I 2  = 51%), and prolonged hospital stay ( SMD  = 0.53, 95% CI  = 0.06-0.99, P  = 0.03, I 2  = 87%). There was no difference in overall mortality, operative time, blood loss, or other complications ( P > 0.05). Subgroup analysis showed that differences in some outcomes lost significance with higher bilirubin levels, fewer PBD cases, studies published after 2010, and strictly select PBD patients ( P < 0.05).

Conclusions: Routine PBD cannot be recommended but it tends to be a better choice in patients with average initial bilirubin above 218.75 μmol/L, portal vein embolization and malnutrition. Further multicenter randomized studies should address the potential advantages of PBD over NPBD, identify clear patient selection criteria, and determine the optimal bilirubin threshold for PBD.