放疗是指利用放射线杀伤肿瘤细胞来提高肿瘤治疗效果的一种局部治疗方法，它不仅可以直接杀伤肿瘤细胞，也可以诱导肿瘤细胞释放肿瘤相关抗原，激活特异性T细胞，从而促进机体产生免疫应答反应。肿瘤的免疫治疗旨在利用患者自身免疫系统杀灭肿瘤细胞和肿瘤组织。放疗可诱导机体产生肿瘤的免疫原性，促进细胞释放细胞内容物，产生"原位疫苗"，这有利于免疫治疗发挥抗肿瘤作用。放疗联合免疫治疗作为一种新的治疗方法已在临床上取得一定的治疗效果。作者对近年来放疗联合免疫治疗的研究进展和面临的挑战作一综述。

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