Introduction The abscopal effect is a rarely observed outcome of radiotherapy wherein there is a reduction in metastatic disease burden outside of the targeted treatment area. Likely due to an in situ vaccine effect of radiotherapy, the abscopal effect may be augmented by immunotherapy. This report is the first case of the abscopal effect observed in metastatic head-and-neck squamous cell carcinoma (hnscc) treated with concurrent radiotherapy and single-agent nivolumab. Case Description An otherwise healthy 57-year-old man underwent craniofacial resection and adjuvant chemoradiotherapy for advanced sinonasal squamous cell carcinoma. Distant metastatic disease developed shortly after primary treatment, and immunotherapy in the form of nivolumab was initiated. Subsequent oligometastatic progression despite immunotherapy prompted palliative radiotherapy to a single metastasis due to pending symptomatology. Post-radiotherapy, the abscopal effect was observed with all distant sites of metastatic disease shrinking. Five months following treatment, a sustained reduction in disease burden has been demonstrated. Summary We present the first case of the abscopal effect in a patient with metastatic hnscc treated with palliative radiotherapy concurrent with single-agent nivolumab immunotherapy, and only the third case of the abscopal effect in metastatic head-and-neck cancer. Dual treatment with immunotherapy and radiotherapy may be an important treatment option in the future, mediated through the abscopal effect.

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放疗联合纳武利尤单抗治疗头颈鳞癌的远隔效应一例报告及文献复习

引言 远隔效应是放射治疗中很少观察到的结果，其中目标治疗区域之外的转移性疾病负担减少。可能由于放射治疗的原位疫苗效应，免疫治疗可能会增强远隔效应。该报告是首例在同步放疗和单药纳武利尤单抗治疗的转移性头颈鳞状细胞癌 (hnscc) 中观察到的远隔效应病例。病例描述 一名原本健康的 57 岁男性因晚期鼻窦鳞状细胞癌接受了颅面切除术和辅助放化疗。初次治疗后不久出现远处转移性疾病，并开始纳武单抗形式的免疫治疗。尽管进行了免疫治疗，但随后的寡转移进展促使由于待症状而对单个转移进行姑息性放疗。放疗后，观察到远隔效应，所有远处转移灶均缩小。治疗五个月后，疾病负担持续减轻。总结 我们报告了第一例转移性头颈癌患者接受姑息性放疗与单药纳武单抗免疫治疗同时治疗时出现的远隔效应病例，也是第三例转移性头颈癌中远隔效应的病例。通过远隔效应介导的免疫疗法和放射疗法的双重治疗可能是未来的重要治疗选择。