Introduction: The abscopal effect is a systemic immune response characterized by metastases regression at sites distant from the irradiated lesion. This systematic review aims to explore the immunological mechanisms of action underlying the abscopal effect and to investigate how hyperthermia (HT) can increase the chances of radiotherapy (RT) triggering systemic anti-tumor immune responses. Methods: This review is created in accordance with the PRISMA guidelines. Results and Conclusion: HT and RT have both complementary and synergistic immunological effects. Both methods trigger danger signal release, promoting cytokine and chemokine secretion, which increases T-cell infiltration and facilitates cell death. Both treatments upregulate extracellular tumor HSP70, which could amplify DAMP recognition by macrophages and DCs, leading to stronger tumor antigen presentation and CTL-mediated immune responses. Additionally, the combined increase in cell adhesion molecules (VCAM-1, ICAM-1, E-selectin, L-selectin) could enhance leukocyte adhesion to tumors, improving lymphocyte trafficking and boosting systemic anti-tumor effects. Lastly, HT causes vasodilation and improves blood flow, which might exacerbate those distant effects. We suggest the combination of local radiotherapy with fever-range whole-body hyperthermia to optimally enhance the chances of triggering the abscopal effect mediated by the immune system.
引言：远隔效应是一种系统性免疫反应，其特征是远离照射部位的转移灶发生消退。本系统性综述旨在探讨远隔效应背后的免疫学作用机制，并研究热疗如何提高放疗触发系统性抗肿瘤免疫反应的可能性。方法：本综述依据PRISMA指南撰写。结果与结论：热疗与放疗具有互补和协同的免疫效应。两种疗法均可触发危险信号释放，促进细胞因子和趋化因子分泌，从而增加T细胞浸润并促进细胞死亡。两种治疗均能上调细胞外肿瘤HSP70表达，可能增强巨噬细胞和树突状细胞对损伤相关分子模式的识别，从而强化肿瘤抗原呈递和细胞毒性T淋巴细胞介导的免疫反应。此外，细胞黏附分子（VCAM-1、ICAM-1、E-选择素、L-选择素）的协同增加可增强白细胞与肿瘤的黏附，改善淋巴细胞归巢并增强系统性抗肿瘤效应。最后，热疗引起的血管舒张和血流改善可能强化上述远隔效应。我们建议将局部放疗与发热范围全身热疗联合应用，以最大程度提高免疫系统介导的远隔效应触发几率。
肿瘤(癌症)患者之家