Feasibility and safety of bisegmentectomy 7–8 while preserving hepatic venous outflow of the right liver – A retrospective cohort study

Background: When a hepatic tumor is deeply located in segments 7 and 8 around the right hepatic vein (RHV), right hemihepatectomy (RH) could be excessive owing to the resection of large tumor-free segments. This study aimed to evaluate the feasibility and safety of bisegmentectomy 7–8 (S7–8) and to compare its surgical outcomes with those of RH. Materials and methods: Consecutive patients who underwent S7–8 and RH were enrolled in this study. In the S7–8 group, 14 patients with an obvious inferior right hepatic vein (IRHV) (median: 6 mm; range: 3.6–8.8 mm) underwent S7–8 without hepatic vein reconstruction. RHV reconstruction was performed in six patients without an IRHV, involving direct anastomosis of the RHV in five patients and reconstruction using a cryo-preserved iliac vein in one patient. Results: A total of 61 patients were included (20 in S7–8 group; 41 in RH group). No significant differences were observed other than higher a model of end-stage liver disease score in the RH group than in the S7–8 group (7 [6–20] vs. 6 [6–9], P = 0.003). Post-hepatectomy liver failure including severe grades was more frequent in the RH group (43.9% vs. 10%, P = 0.008). In the S7–8 group, two patients with direct RHV reconstruction had RHV anastomosis obstruction, and eventually required insertion of a metallic stent. However, computed tomography performed 4 weeks after the operation showed intact venous outflow of the right liver in the S7–8 group. Conclusion: S7–8 can be performed safely in selected patients with a thick IRHV. For patients with no obvious IRHV, RHV reconstruction could be a good surgical strategy to retain venous outflow of the right liver with feasible outcomes.