Preoperative biliary drainage of the hepatic lobe to be resected does not affect liver hypertrophy after percutaneous transhepatic portal vein embolization

Background: In patients with malignant perihilar biliary strictures, preoperative biliary drainage (PBD) of the hepatic lobe to be resected may decrease the liver volume of the future liver remnant (FLR) after percutaneous transhepatic portal vein embolization (PVE). However, evidence of its application is insufficient. This study aimed to clarify the effects of PBD on liver hypertrophy after PVE. Methods: Between January 2008 and December 2017, 169 patients with malignant perihilar biliary strictures underwent major hepatectomy or palliative surgery at our hospital. Of these, 76 patients who underwent PVE were categorized into two groups: group A (n = 29) who received unilateral PBD of the FLR and group B (n = 47) who received bilateral PBD, including that of the hepatic lobe to be resected. FLR ratios after PVE and liver hypertrophy ratios were retrospectively compared in both groups. Results: Group B exhibited significantly severe biliary stenosis (p = 0.0038) and high serum bilirubin before biliary drainage (p = 0.0037). After PVE, the total liver volumes were 1287 ± 260 ml and 1340 ± 257 ml (p = 0.39), respectively. FLR volumes were 555 ± 135 and 577 ± 113 ml (p = 0.45), respectively. FLR ratios were 43.4 ± 8.2% and 43.4 ± 6.4%, respectively (p = 0.98). Liver hypertrophy ratios were 124.2 ± 17.7% and 129.2 ± 20.9%, respectively (p = 0.28). In addition, an examination which excluded patients with Bismuth type I obtained similar result. Conclusions: PBD of the hepatic lobe to be resected did not decrease the FLR ratios and hypertrophy ratios. Thus, in patients with poor biliary drainage, additional PBD of the target lobe is acceptable.