Progression-free and overall survival for study cohort of patients with limited-stage SCLC. (A) Progression-free survival of the cohort of patients in whom we ever detected circulating tumor DNA (ctDNA) after definitive therapy (n = 15, blue line) versus never detected ctDNA after definitive therapy (n = 8, red line). (B) Overall survival of the cohort of patients in whom we ever detected ctDNA after definitive therapy (n = 15, blue line) versus never detected ctDNA after definitive therapy (n = 8, red line). LS-SCLC, limited-stage SCLC.