The clinical application of lazertinib, a third‐generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, has extended to the treatment of EGFR‐mutant non‐small‐cell lung cancer (NSCLC); however, the effects of its dose modification on its efficacy and safety have not yet been adequately established. Here, EGFR is linked to non-small cell lung carcinoma.