POLE and cancer: Patients with high mutation loads, ie, the number of mutations per million bases (mb) in target regions, are more susceptible to immune checkpoint inhibitors (eg PD‐1 or PD‐L1‐mediated immunotherapy) than the patients with low mutation loads in lung and other cancers.34, 50, 51 Some mutations in mismatch repair genes, homologous recombination genes, or POLE have been associated with high mutation load.30, 52 As previously reported, we found that mutation load varied among lung cancer patients and we identified six genes that could significantly affect patient mutation load34 (Figure 2D‐E).