贝伐珠单抗与阿替珠单抗联合使用可通过激活免疫反应来增强治疗的抗肿瘤效果。该组合被批准用于治疗不可切除的肝细胞癌（HCC）。根据实验模型，远隔效应与辐射诱导的免疫原性细胞死亡引发的免疫反应有关。因此，结合放射治疗和免疫治疗预计会引起远隔效应。然而，由于临床病例很少，免疫治疗在远隔效应中的临床意义仍不清楚。在此，我们报告一例伴有肺和肾上腺转移的晚期 HCC 病例。立体定向放射治疗 (SBRT) 后，atezolizumab 和贝伐单抗 (atezo/bev) 的抗肿瘤功效得到增强，尽管 atezo/bev 在 SBRT 前没有产生足够的治疗反应。此外，在单独使用阿替利珠单抗期间未观察到 SBRT 后的远隔效应，但在恢复贝伐珠单抗与阿替利珠单抗联合治疗后出现了这种效应，最终使患者达到完全缓解状态。这些发现表明，放疗后的免疫激活可能与临床实践和实验环境中诱导远隔效应有关，并且将免疫治疗与放疗后贝伐珠单抗相结合可能会在 HCC 病例中引起远隔效应，即使免疫治疗单独使用检查点抑制剂可能不够。© 2024。日本胃肠病学会。

Combining bevacizumab with atezolizumab enhances the antitumor effects of the treatment by activating an immune response. This combination is approved for the treatment of unresectable hepatocellular carcinoma (HCC). An abscopal effect is associated with an immune response triggered by radiation-induced immunogenic cell death, based on experimental models. Thus, combining radiotherapy and immunotherapy is expected to induce an abscopal effect. However, the clinical significance of immunotherapy in the abscopal effect remains unknown due to the rarity of clinical cases. Herein, we report a case of advanced HCC with lung and adrenal metastases. The antitumor efficacy of atezolizumab and bevacizumab (atezo/bev) was enhanced following stereotactic body radiotherapy (SBRT), although atezo/bev did not yield a sufficient therapeutic response pre-SBRT. Furthermore, an abscopal effect following SBRT was not observed during atezolizumab alone but was evoked after resuming bevacizumab in combination with atezolizumab, culminating in the patient achieving a complete response status. These findings suggest that immune activation following radiotherapy may be related to the induction of an abscopal effect in clinical practice as well as in experimental settings, and combining immunotherapy with bevacizumab post-radiotherapy could evoke an abscopal effect in a case of HCC, even though immune checkpoint inhibitor use alone may be insufficient.© 2024. Japanese Society of Gastroenterology.