Traditional cancer treatment approaches have focused on surgery, radiation therapy, and cytotoxic chemotherapy. However, with rare exceptions, metastatic cancers were considered to be incurable by traditional therapy. Over the past 20 years a fourth modality – immunotherapy – has emerged as a potentially curative approach for patients with advanced metastatic cancer. However, in many patients cancer “finds a way” to evade the anti-tumor effects of immunotherapy. Immunotherapy resistance mechanisms can be employed by both cancer cells and the non-cancer elements of tumor microenvironment. This review focuses on the resistance mechanisms that are specifically mediated by cancer cells. In order to extend the impact of immunotherapy to more patients and across all cancer types, and to inhibit the development of acquired resistance, the underlying biology driving immune escape needs to be better understood. Elucidating mechanisms of immune escape may shed light on new therapeutic targets, and lead to successful combination therapeutic strategies.

传统的癌症治疗方法主要集中在手术、放射治疗和细胞毒性化学疗法上。然而，除了极少数例外，转移性癌症被认为是传统疗法无法治愈的。在过去的 20 年中，第四种方式——免疫疗法——已经成为晚期转移性癌症患者的潜在治愈方法。然而，在许多患者中，癌症“找到了一种方法”来逃避免疫疗法的抗肿瘤作用。癌细胞和肿瘤微环境的非癌成分都可以利用免疫疗法抗性机制。本综述重点关注由癌细胞特异性介导的耐药机制。为了将免疫疗法的影响扩展到更多患者和所有癌症类型，并抑制获得性耐药性的发展，需要更好地理解驱动免疫逃逸的潜在生物学。阐明免疫逃逸的机制可能会揭示新的治疗靶点，并导致成功的联合治疗策略。