Kletzl et al. reported, in a retrospective study of 157 EGFR-mutated advanced NSCLC patients treated with erlotinib or gefitinib, that co-administration of acid-suppressant therapy did not significantly affect the efficacy (overall response rate (ORR) and progression-free survival (PFS)) in the overall cohort [24]. Here, EGFR is linked to non-small cell lung carcinoma.