Segment IVb and V liver resection (versus wedge resection)

The gallbladder lies in a fossa between Couinaud segments IVb and V, and hepatic-side (T2b) tumours drain and spread into them. Radical cholecystectomy therefore removes either a non-anatomical wedge of liver around the fossa or the two segments in full. A 2023 systematic review of nine studies and 2,086 T2 patients (627 segmental, 1,459 wedge) found one-year disease-free survival higher after segmental resection (risk ratio 1.07) but no difference at three or five years, three-year overall survival lower after segmental resection (risk ratio 0.90; hazard ratio for death 1.33), more postoperative complications (risk ratio 1.90) and no difference in intrahepatic recurrence, and concluded the choice should weigh the patient's condition and the surgeon's experience (Chen 2023). The T2 side matters: T2b tumours have more vascular and neural invasion and nodal spread, and liver resection appears to improve survival in T2b in the 2022 meta-analysis of 2,531 patients (Shindoh 2015; Alrawashdeh 2022).