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 cm(3) vs 70 cm(3) ), 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.