The CHOP Study – Cholestatic Influence on Portal Vein Embolization (PVE) Induced Future Liver Remnant (FLR) Hypertrophy – A Maastricht Aachen Analysis

Abstract

Introduction: Experimentally induced hepatocellular bile salt accumulation impairs liver function and regeneration. Portal Vein Embolisation (PVE) is the current standard to induce FLR hypertrophy. The impact of cholestasis on PVE-induced FLR hypertrophy however remains unclear. We hypothesized that cholestasis impairs PVE induced FLR hypertrophy and compared PVE hypertrophic response between patients with and without cholestasis. Methods: Patients with perihilar cholangiocarcinoma or colorectal liver metasases, who had undergone PVE before a major hemihepatectomy in Uniklinik RWTH Aachen or Maastricht University Medical Center between 2016 and 2019, were enrolled. Clinical and laboratory variables were recorded and volume of segment 2 and 3 on pre- and post-embolization CT-scans were assessed. Diameters of left and right hepatic bile ducts was measured on pre-embolization scans. Bilirubin was used as a clinical marker of cholestasis. The degree of hypertrophy (DH) as a percentage and kinetic growth rate (KGR) as percentage/week were used to assess the increase of the liver volume. Results: In this study,142 patients were enrolled. Sequential pre- and post-CT-scans were available for 53 patients (32 for CRLM, 21 for pCCA). Liver segment II and III volumes increased significantly after PVE in both groups (P < 0.001). pCCA patients with cholangitis (n=4) had an almost blunted DH (P = 0.042). DH and KGR did not differ (P = 0.719 and P = 0.968, respectively) between drained and undrained pCCA patients. Higher initial bilirubin level before biliary drainage was correlated with less PVE-induced DH (ρ=-0.727, P = 0.007). The bilirubin level and bile duct diameter before PVE was not associated with DH and KGR. Conclusion: Initial bilirubin levels before biliary drainage were negatively correlated with PVE-induced liver hypertrophy in patients with pCCA. Biliary duct diameter and bilirubin level right before PVE seems less of influence on PVE induced hypertrophy.