Molecular subtyping of small cell lung cancer

Small cell lung cancer (SCLC), originating from lung neuroendocrine stem cells, is a common pulmonary malignant tumor. SCLC, with poor prognoses, accounts for approximately 13-15% of all lung cancer cases. Due to the slow progress of clinical treatment, the 5-year survival rate of SCLC has remained below 7% for many years. In recent years, with the development and popularity of gene sequencing technologies, we were able to better grasp patterns of gene mutations and tumor evolution in SCLC. Thus, appropriate molecular subtyping strategies have been established to help predict patients' prognoses and develop the treatment regimen for SCLC more accurately. In this narrative review, we aim to summarize the evolution of mutation-based molecular subtyping of SCLC, as well as the trends in molecular targeting and immunotherapeutic for SCLC. Based on the latest sequencing data for SCLC, thereafter, we discuss therapeutic opinions of SCLC from basic to clinic. This review may provide a basis for guiding the development of subsequent individualized precision-targeted therapy for SCLC patients to improve their clinical prognoses.