摘要肺癌的发病率和病死率在所有恶性肿瘤中呈逐年上升的趋势，其中小细胞肺癌(SCLC)约占所有肺癌的14%。由于SCLC早期不易发现，易复发转移，治疗效果不佳，平均5年生存率不超过10%。曾有研究显示化疗对34%～85%的SCLC有效，但疾病进展迅速，后续二线治疗效果很不理想。随着美国食品药品监督管理局批准卡铂、依托泊苷联合抗程序性细胞死亡配体1抑制剂atezolizumab作为一线治疗，单药抗程序性细胞死亡蛋白1抑制剂nivolumab和pembrolizumab作为三线治疗，免疫检查点抑制剂逐渐进入SCLC的治疗中。现对SCLC免疫治疗的临床研究及生物标志物研究进展进行综述。

abstractsAmong all malignant tumors, the morbidity and mortality of lung cancer are increasing yearly, small cell lung cancer (SCLC) accounts for approximately 14% of all lung cancers.Because SCLC is not easily detected in the early stage, it tends to relapse and metastasize, and has a poor treatment effect, the average five-year survival rate does not exceed 10%.Previous studies have shown that chemotherapy is effective for 34% to 85% of SCLC, but the disease progresses rapidly, and the effect of subsequent second-line treatment is very unsatisfactory.Food and Drug Administration of America approved carboplatin, etoposide and programmed cell death ligand 1 inhibitor atezolizumab as first-line treatment.Programmed cell death protein 1 inhibitors nivolumab and pembrolizumab as monotherapy in third-line treatment.Immune checkpoint inhibitors gradually entered the treatment of SCLC.The clinical research and biomarkers of SCLC immunotherapy are summarized and sorted out.