肿瘤免疫检查点抑制剂治疗:影像学表现总结

Immune checkpoint inhibitors are a new class of cancer therapeutics that have demonstrated striking successes in a rapid series of clinical trials. Consequently, these drugs have dramatically increased in clinical use since being first approved for advanced melanoma in 2011. 

免疫检查点抑制剂是一类新的癌症治疗药物，已在一系列快速临床试验中取得了巨大成功。 因此，自2011年首次批准用于晚期黑色素瘤以来，这些药物的临床使用量急剧增加。

Current indications in addition to melanoma are non-small cell lung cancer, head and neck squamous cell carcinoma, renal cell carcinoma, urothelial carcinoma, and classical Hodgkin lymphoma. A small subset of patients treated with immune checkpoint inhibitors undergoes an atypical treatment response pattern termed pseudoprogression: New or enlarging lesions appear after initiation of therapy, thereby mimicking tumor progression, followed by an eventual decrease in total tumor burden. 

除黑色素瘤外，目前的适应症包括非小细胞肺癌、头颈部鳞状细胞癌、肾细胞癌、尿路上皮癌和经典霍奇金淋巴瘤。 少部分用免疫检查点抑制剂治疗的患者会经历非典型治疗反应模式，称之为假性进展：在开始治疗后出现新的或扩大的病变，从而表现出“肿瘤进展”，而最终总肿瘤负荷减少。

Traditional response standards applied at the time of initial increase in tumor burden can falsely designate this as treatment failure and could lead to inappropriate termination of therapy. Currently, when new or enlarging lesions are observed with immune checkpoint inhibitors, only follow-up imaging can help distinguish patients with pseudoprogression from the large majority in whom this observation represents true treatment failure. 

在肿瘤负荷初始增加时，应用的传统反应标准可能错误地将其指定为治疗失败，并且可能导致不适当地终止治疗。 目前，当用免疫检查点抑制剂观察到新的或扩大的病变时，只有影像学随访能够帮助鉴别假性进展患者与大多数观察结果表明真正治疗失败患者。

Furthermore, the unique mechanism of immune checkpoint inhibitors can cause a distinct set of adverse events related to autoimmunity, which can be severe or life threatening. Given the central role of imaging in cancer care, radiologists must be knowledgeable about immune checkpoint inhibitors to correctly assess treatment response and expeditiously diagnose treatment-related complications. 

此外，免疫检查点抑制剂的独特机制可引起与自身免疫相关的一组不同的不良事件，其可能很重甚至会危及患者生命。 鉴于影像学在癌症治疗中的核心作用，放射科医师必须了解免疫检查点抑制剂，以正确评估治疗反应并迅速诊断治疗相关并发症。

The authors review the molecular mechanisms and clinical applications of immune checkpoint inhibitors, the current strategy to distinguish pseudoprogression from progression, and the imaging appearances of common immune-related adverse events. 

Wang, G. X., et al. (2017). "Immune Checkpoint Inhibitor Cancer Therapy: Spectrum of Imaging Findings." Radiographics 37(7): 2132-2144.