FLT1 and non-small cell lung carcinoma: It is worth noting that circulating IgG for the CD25‐MUC1‐VEGFR1 combination had the highest sensitivity of 49.6% against a specificity of 95%, with an AUC of 0.883 (95% CI 0.844–0.923) in early‐stage NSCLC, suggesting that natural antibodies for this combination may be an effective biomarker for early diagnosis of NSCLC.