In the whole set, the median level of IDH2 in the serum from patients with NSCLC was 12.53 ± 7.76 ng·mL−1, which was significantly higher than that of the healthy controls (6.48 ± 4.29 ng·mL−1; Fig. 2C; P < 0.0001, Mann–Whitney U‐test). Here, IDH2 is linked to non-small cell lung carcinoma.