Correlation between liver volume drainage and clinical success after endoscopic biliary drainage of hilar malignant obstruction.

Background and aim: Malignant hilar obstruction usually presents in advanced-stage disease with a poor prognosis. Effective biliary drainage is essential for the beginning of palliative chemotherapy. There is a debate on the amount of liver parenchyma that should be drained to achieve clinical success. This study aimed to correlate the volume of liver drained with clinical success rate.

Methods: The authors conducted a retrospective study including patients with malignant hilar biliary obstruction who underwent retrograde endoscopic cholangiography for biliary drainage from January 2014 to December 2018. The main outcome was a correlation of clinical success rate with hepatic volume drained. Secondary outcomes were correlation of clinical success rate with the quantity of liver sectors drained and unilateral versus bilateral drainage.

Results: 82 patients met inclusion criteria (58.5 % female), with a mean age of 60±13 years. The main cause of hilar obstruction was cholangiocarcinoma (32.9 %) followed by lymph node metastasis (23.2 %). Technical success was achieved in 75 patients (91.5 %), and clinical success in 45 patients (60 %). The authors found a significant correlation between clinical success rate when at least 50 % of viable parenchyma was drained (p = 0.016; OR = 4.15, 95 % CI 1.4-12.5). Considering liver sectors, higher clinical success rates were found when at least 2 sectors were drained (p < 0.001; OR = 8.50, 95 % CI 2.7-26.7). The correlation between unilateral versus bilateral drainage and clinical success was not statistically significant.

Conclusion: Drainage of at least 50 % of volume hepatic parenchyma was associated with better outcomes as well as drainage of at least 2 hepatic sectors, regardless of if unilateral or bilateral.