Adjuvant radiotherapy and chemotherapy offer a recurrence and survival benefit in patients with resected perihilar cholangiocarcinoma

Background and objectives: The objective of this study was to investigate the benefits of adjuvant treatment for patients with resected perihilar cholangiocarcinoma (PHC). Methods: Between 2001 and 2017, 196 patients with PHC adenocarcinoma underwent curative resection. The patients were divided into four groups according to adjuvant treatment type: surgery alone (S; N = 90), surgery with chemotherapy (S+CTx; N = 67), surgery with radiotherapy (S+RTx; N = 18), and surgery with chemoradiotherapy (S+ CRTx; N = 21). Results: The median follow-up duration of the surviving patients was 58 months. The 5-year rate of overall survival (OS) was 32%. In multivariate analysis, receiving S+CTx and S+CRTx were significant prognostic factors for OS. In subgroup analyses of the R1 resection patients, the S+CRTx group showed better OS than the S group (p < 0.05). In subgroup analyses of the stage III–IVA patients with a negative resection margin, the S+CTx and S+CRTx groups showed superior OS than the S group (p < 0.05). Conclusions: Our data suggest that adjuvant chemoradiotherapy might be considered for PHC patients with R1 resection. Adjuvant chemotherapy or chemoradiotherapy is suggested for stage III–IVA patients with R0 resection. The results of this study require validation through further prospective studies.