BACKGROUND: Hemihepatectomy with extrahepatic bile duct resection is considered the only curative treatment for perihilar cholangiocarcinoma. The aim of the study was to clarify the survival benefits in this invasive surgical procedure for elderly patients. METHODS: A total of 290 patients who underwent surgical resection for perihilar cholangiocarcinoma in our department from 2000 to 2020 were categorized into the E group (62 patients aged ≥75 years) and NE group (228 patients aged <
74 years). RESULTS: The E group exhibited decreased pathological lymph node metastasis (p = .001) and had a shorter operative time (p = .021) and fewer cases of combined vascular resection (p = .002). We found no significant differences in postoperative mortality
however, disease-specific survival was significantly better in the E group (3-year survival: 75.6 vs. 60.3%, p = .031). After propensity score matching, overall survival and disease-specific survival did not differ between the two groups
nevertheless, the hospital mortality rate was significantly higher in the E group (11.5 vs. 1.6%, p = .020). In the E group, a high preoperative Glasgow prognostic score was the only factor associated with hospital mortality (odds ratio, 7.35
p = .026) and indicated worse prognosis. CONCLUSIONS: A high preoperative Glasgow prognostic score was associated with hospital mortality and poor prognosis in elderly patients with perihilar cholangiocarcinoma.