In the independent validation set (A), PulmoSeek performance in early stage cancer: sensitivity was 100% in stage 0 (n = 2), 94.1% in stage IA (n = 85), and 100% in stage 1B (n = 5). (B) PulmoSeek performance in stage IA substages: sensitivity was 86.4% in stage IA1 (n = 22), 95.0% in stage IA2 (n = 40), and 100% in stage 1A3 (n = 23).