Objective:Merkel cell carcinoma (MCC) is a rare and aggressive form of skin cancer. Although immunotherapy has transformed MCC management, published data remain limited. This comprehensive review evaluates current evidence on immune checkpoint inhibitors (ICIs) in MCC, in relation to other treatment modalities such as surgery and radiotherapy.Methods:Peer-reviewed articles published between January 2000 and August 2025 were searched manually in four databases: Scopus, ScienceDirect, PubMed and MEDLINE, using the keywords “Merkel cell carcinoma” AND “immunotherapy” AND “immune checkpoint inhibitors”. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) methodology was employed.Results:ICIs can be given in different settings: (A)Neoadjuvant: The CheckMate 358 trial reported a 54.5% response rate among 33 radiologically evaluable patients treated with nivolumab, each showing over 30% tumor reduction. (B)Adjuvant: (1) The ADMEC-O phase II trial demonstrated improved disease-free survival with adjuvant nivolumab. (2) The ADAM phase III trial evaluates adjuvant avelumab in node-positive patients post-surgery/radiation, with common side effects including nausea, fatigue, and itching. (3) STAMP, a phase III trial, investigates pembrolizumab in stage I–III MCC. Both ADAM and STAMP have completed accrual and results are pending. (C)Primary therapy: KEYNOTE-017 and JAVELIN trials reported a 60% overall response rate and ~40% 3-year progression-free survival with first-line pembrolizumab or avelumab. Both agents also show promise as salvage therapies.Conclusions:ICIs demonstrate encouraging outcomes in MCC across various treatment stages. Continued research is essential to optimize treatment timing and integrate multimodal therapies.
目的：默克尔细胞癌（MCC）是一种罕见且侵袭性强的皮肤癌。尽管免疫疗法已改变了MCC的治疗格局，但已发表的数据仍有限。本综述系统评估了免疫检查点抑制剂（ICIs）在MCC治疗中的现有证据，并探讨其与手术、放疗等其他治疗方式的关系。 方法：通过人工检索Scopus、ScienceDirect、PubMed和MEDLINE四个数据库，收集2000年1月至2025年8月期间发表的同行评议文献，检索关键词为“默克尔细胞癌”与“免疫疗法”与“免疫检查点抑制剂”。采用系统综述与荟萃分析优先报告条目（PRISMA）方法进行文献筛选与分析。 结果：ICIs可在不同治疗场景中应用：（A）新辅助治疗：CheckMate 358试验显示，33例经影像学评估的患者接受纳武利尤单抗治疗后，客观缓解率达54.5%，所有缓解者肿瘤缩小均超过30%。（B）辅助治疗：（1）ADMEC-O II期试验证实辅助性纳武利尤单抗可改善无病生存期；（2）ADAM III期试验正在评估术后/放疗后淋巴结阳性患者使用阿维鲁单抗辅助治疗的效果，常见副作用包括恶心、疲劳和瘙痒；（3）STAMP III期试验正在研究帕博利珠单抗在I–III期MCC患者中的应用。ADAM与STAMP试验已完成入组，结果待公布。（C）一线治疗：KEYNOTE-017和JAVELIN试验显示，一线使用帕博利珠单抗或阿维鲁单抗的总体缓解率达60%，3年无进展生存率约40%。两种药物在挽救治疗中也显示出潜力。 结论：ICIs在MCC各治疗阶段均展现出令人鼓舞的疗效。未来需持续开展研究以优化治疗时机，并推进多模式治疗的整合应用。
Immune Checkpoint Inhibitors in Merkel Cell Carcinoma of the Skin: A 2025 Comprehensive Review
肿瘤(癌症)患者之家