小细胞肺癌（SCLC）是一种高度恶性的肿瘤，预后非常差，因此迫切需要更有效的治疗方法来治疗患有此病的患者。近年来，基于SCLC的关键转录因子的新兴分子分类为肿瘤的病理生理学、转移、免疫微环境和获得性治疗抵抗提供了更多信息，并反应了各种SCLC表型的肿瘤间异质性。此外，基因组学和单细胞测序分析的进展进一步揭示了该疾病的高度肿瘤内异质性和可塑性。在这里，我们回顾和总结这些近期的证据，并讨论SCLC的可能致病机制。2023年中国医学会版权所有，由沃尔特斯·克鲁沃公司根据CC-BY-NC-ND许可发布。

Small cell lung cancer (SCLC) is a highly malignant tumor with a very poor prognosis; therefore, more effective treatments are urgently needed for patients afflicted with the disease. In recent years, emerging molecular classifications based on key transcription factors of SCLC have provided more information on the tumor pathophysiology, metastasis, immune microenvironment, and acquired therapeutic resistance and reflected the intertumoral heterogeneity of the various SCLC phenotypes. Additionally, advances in genomics and single-cell sequencing analysis have further revealed the high intratumoral heterogeneity and plasticity of the disease. Herein, we review and summarize these recent lines of evidence and discuss the possible pathogenesis of SCLC.Copyright © 2023 The Chinese Medical Association, produced by Wolters Kluwer, Inc. under the CC-BY-NC-ND license.