marginally non-significantP = 0.730
KM analysis for IV CSCLC, IV SCLC and IV NSCLC after PSM After PSM, the mOS and mCSS for patients with IV CSCLC were both 6.00 months, while those for SCLC patients were 5.00 months, there were marginally non-significant differences in OS (P = 0.730; Fig 5A ) and CSS (P = 0.685; Fig 5B ) between IV CSCLC and IV SCLC groups.