Figure 1 .

Study design and key clinical characteristics of the SCLC patients from the discovery cohort

A. A flowchart of our study scheme. B. Clinical characteristics of the patients from the discovery cohort. C. The Kaplan–Meier plots showing the limited predictive values on patient OS of the VALG, TNM, and ASCL1/NeuroD1 staging and classification methods. SCLC, small cell lung cancer; TNM, tumor–node–metastasis; VALG, Veterans Administration Lung Study Group; OS, overall survival; PFS, progression-free survival; ICI, immune checkpoint inhibitor; LNM, lymph node metastasis; LS, limited stage; ES, extensive stage.