a Mutational landscape of SCLC (n = 40). Mutated gene frequency >15% involved in previously reported significant mutated genes in SCLC are shown for each region of the individual patient. Upper, TMB count; middle, heatmap for driver mutations; lower, mutational signatures. b Counts in clonal and subclonal mutations for each patient (n = 40). c Percentage of subclonal mutations for each patient (n = 40). SCLC small cell lung cancer, P-SCLC pure small cell lung cancer, C-SCLC combined small cell lung cancer, SNVs single-nucleotide variants, CDS coding sequence.