The median age at the time of diagnosis was 57 years (range: 19-80 years). Four patients were female, and 11 were male. A total of 25 lesions were irradiated in 15 patients between January 2019 and July 2020. Sixteen of these lesions were re-irradiation, and three of them received the 3rd course of RT. At the last control, four patients were dead; one was due to disease progression. Eight patients had complete responses, one had a partial response, four had stable diseases, and two had progressive diseases. None of the lesions irradiated via SBRT with concurrent ICI progressed during the follow-up except for one. Therefore, the SBRT-C rate was 96%. The 6-, 12-, and 24-month OS rate was 93%, 76%, and 57%; the PFS rate was 86%, 50% and 33%, %the LRFS rate was 86%, 70%, and 53%, the RRFS rate was 86%, 65%, and 49%, and the DMFS rate was 93%, 61%, and 46%, respectively. Mean OS was 21.2 months (standard error [SE]:2.2, 95% confidence interval [CI]: 17.7-25.7) and mean PFS was 16.2 months (SE: 2.4, 95% CI: 11.4-20.9). The abscopal effect was observed in two patients who both had nasopharyngeal cancer. Acute grade 1 SBRT-related dermatitis was observed in only one patient and no other acute side effects were observed. A stent was placed in the carotid artery in two patients prior to re-irradiation due to the late SBRT-related carotid blowout syndrome (CBOS) risk. In one patient CBOS could be prevented but the other patient succumbed to CBOS. Other late SBRT-related side effects were observed in three patients (dysphagia, pituitary insufficiency, skull base osteomyelitis). A total of five patients developed ICI-related toxicity (recall dermatitis in one patient and hypothyroidism in four patients).