Evolving role of radiation therapy in advanced/metastatic intrahepatic cholangiocarcinoma

Table 1 Summary of key studies on radiation as a neoadjuvant and adjuvant treatment modality in intrahepatic cholangiocarcinoma

Therapy type	Study/protocol	Regimen (RT + chemo)	Patient population	Key outcomes
Neoadjuvant	NACRAC[48]	45 Gy EBRT + Gemcitabine	Borderline/Locally advanced hilar CCA	R0 resection 89.6%
	SBRT + LT[49]	30-45 Gy SBRT + Capecitabine	Unresectable iCCA, transplant cohort	Pathologic CR in 3/6, 83% 1-year survival
Adjuvant	NCDB analysis[47]	RT (dose varies)	GBC, extrahepatic CCA, N+/R1	OS improvement in high-risk groups
	RT for iCCA[43]	NA	Resected iCCA, high-risk	Median OS 11 months

SBRT: Stereotactic body radiation therapy; EBRT: External beam radiation therapy; GBC: Gall bladder cancer; iCCA: Intrahepatic cholangiocarcinoma; CR: Complete response; OS: Overall survival; LT: Liver transplantation; RT: Radiation therapy; NCDB: National Cancer Database; NACRAC: Neoadjuvant chemoradiation therapy.

Table 2 Summary of key studies on stereotactic body radiation therapy in intrahepatic cholangiocarcinoma

Ref.	Unresectable/metastatic	No.	Follow up (months)	mOS (months)	mPFS (months)	Adverse effects
Tse et al[50], 2008	Unresectable	10	NA	15	NA	RILD: 0%
Tao et al[20], 2016	Unresectable	79	33	30	30	Biliary complication: 33%
Liu et al[56], 2017	Unresectable	12	29	12.6	NA	RILD: 0%
Chen et al[51], 2010	Unresectable	35	7	9.5	NA	Grade II transaminitis
Weiner et al[57], 2016	Unresectable	12	8.8	13.2	24.7	Grade 3/4 reaction: 16%
Zhang et al[23], 2023	Unresectable	43	15	12	6	RILD: 0%
Shen et al[58], 2017	Unresectable	28	16	15	11	RILD: 7.1%
Kozak et al[59], 2020	Unresectable	25	18	23	NA	NA
Sharma et al[60], 2025	Unresectable/metastatic	17	14	21	10	RILD: 0%

RILD: Radiation-induced liver disease; M1: Metastatic; mOS: Median overall survival; mPFS: Median progression-free survival; NA: Not available.