EGFR and adenocarcinoma: In summary, the principal findings suggest that firstly, CA-125, CA-153, and CA-199, increased with advancing stages of lung adenocarcinoma patients; secondly, in patients with stage IV adenocarcinoma, higher CA-125 and CA-199 levels may predict poor PFS; and thirdly, higher CA-125 levels were associated with poor PFS in patients with stage IV adenocarcinoma receiving EGFR TKIs.