Afatinib was utilized to treat nine patients with NSCLC who had already had EGFR 20 insertional mutations in a large retrospective study: four with S768_D770dup, one with N771_H773dup, two with H773_V774dup, one with H773dup, and one with V769_D770insGVV. Here, EGFR is linked to non-small cell lung carcinoma.