EGFR and adenocarcinoma: Regarding targeted agents, several studies suggest that adenocarcinoma patients benefit more from epidermal growth factor receptor (EGFR)–tyrosine kinase inhibitor (TKI) therapy than squamous cell carcinoma patients, both subtypes bearing EGFR mutations, where objective response rates, OS, and progression-free survival (PFS) are 66–74%, 19–21 months, and 9.4–10 months (9) versus 25–27%, 13.48 months, and 3–5 months (10, 11), respectively.