Evaluation of segment 4 portal vein embolization added to right portal vein for right hepatic trisectionectomy: A retrospective propensity score‐matched study.

Background: Adding segment 4 (S4) portal vein embolization (PVE) to right PVE before right hepatic trisectionectomy is controversial. We retrospectively examined the effect of S4 PVE on segments 2 and 3 (S2 + 3) hypertrophy. Methods: We reviewed patients with biliary carcinoma who underwent right PVE with (R3PVE) or without (R2PVE) S4 PVE using gelatin sponge particles and coils (2010‐2019). Propensity score matching balanced the cohort for baseline characteristics, including total liver volume and S2 + 3 volume before PVE. We compared the groups regarding the S2 + 3 volume changes after PVE. Results: Of 178 enrolled patients, 38 underwent R3PVE for right hepatic trisectionectomy and 140 underwent R2PVE for right hepatectomy. Twenty‐eight patients from each group were respectively matched. The median absolute volume increase in (146 cm3 vs 70 cm3), hypertrophy rate of (52.4% vs 32.3%), and kinetic growth rate of (3.1%/wk vs 2.0%/wk) S2 + 3 were significantly higher in the R3PVE group than in the R2PVE group. In the pre‐matched cohort, the rate of posthepatectomy liver failure and postoperative hospital stay did not significantly differ between the patients who underwent right hepatic trisectionectomy and right hepatectomy. Conclusion: R3PVE increased the S2 + 3 volume more effectively than R2PVE in patients with biliary carcinoma. [ABSTRACT FROM AUTHOR]