Table 1.

Summary of representative studies on the combination of radiotherapy with immunotherapy in main cancer types investigated to date

Cancer type	Patient Characteristics	Number of patients	Status of TMB/MSI/MMR/PD-L1	Treatment	Outcome	References
Melanoma	advanced melanoma	25	Not Specified	RT + nivolumab or pembrolizumab	CR&PR&SD&PD in irradiated lesions: 24,12,24,32%;in nonirradiated lesions: 20, 19, 12, 40%	[25]
	metastatic melanoma	59	Not Specified	17:RT + nivolumab or pembrolizumab 42:nivolumab or pembrolizumab	RT + anti-PD-1 therapy vs anti-PD-1 therapy, ORR: 64.7% VS 33.3%;	[26]
	metastatic melanoma	101	Not Specified	70: concurrent radiotherapy with ipilimumab (Ipi-RT); 31 ipilimumab alone	OS significantly increased (19 vs 10 months). Median PFS marginally increased (5 vs 3 months). CR rate significantly increased (25.7% vs 6.5%), OR rate increaed (37.1% vs 19.4%).	[24]
NSCLC	recurrence after at least 1 prior platinum-containing regimen	1736 (18 studies)	Not Specified	RT + nivolumab, or pembrolizumab, or ipilimumab	Local Control Rate (CR + PR + S): 70.7%; median OS: 12.4 months; PFS: 4.6 months;Distant/Abscopal Response Rate (CR + PR + S):41.3%;Toxicity ≥Grade 3:20.0%	[27]
Solid tumors	metastatic solid tumor previously treated with standard-of-care therapy	73 (27 cancer types)	Not Specified	RT + pembrolizumab	overall ORR: 13.2%; Median OS: 9.6 months; Median PFS: 3.1 months; nonirradiated ORR: 26.9%	[34]

TMB tumor mutation burden, MSI microsatellite instability, MMR mismatch repair, PD-L1 programmed death ligand-1, NSCLC non-small cell lung cancer, CR complete response, PR partial response, SD stable disease, PD progressive disease, OS overall survival, ORR objective response rate, PFS progression free survival, RT radiotherapy