IDH2 and non-small cell lung carcinoma: We found a level of IDH2 at 7.26 ± 3.98 ng·mL−1 in serum from patients with NSCLC at 1 week after surgery, which was significantly lower than level before surgery (11.27 ± 3.51 ng·mL−1, P < 0.0001, Mann–Whitney U‐test, Fig. 4A) and approached the level of that observed in healthy control subjects (6.57 ± 5.10 ng·mL−1, P = 0.91, Mann–Whitney U‐test; Fig. 4B).