Non-small cell lung cancer (NSCLC) patients with higher carcinoembryonic antigen (CEA) levels tend to have mutant epidermal growth factor receptor (EGFR). Thus, in patients with unknown EGFR mutation status, those with higher CEA are more likely to response to EGFR-tyrosine kinase inhibitors (TKIs). However, patients with higher CEA also have more tumor burden. With the above paradoxical evidence, it is prudent to understand the prognostic significance of baseline CEA in patients with EGFR-mutant NSCLC treated with first-line EGFR-TKIs. The clinical significance of the trend in CEA after treatment and the impact of CEA normalization during EGFR-TKI therapy are also unknown and potentially important.
241 patients who received first-line EGFR-TKIs were included. Patients were divided into 3 groups accordingly to their CEA response. In group A, 1-month follow-up CEA level decreased more than 35% with nadir CEA normalization; in group B, 1-month follow-up CEA level decreased more than 35% without nadir CEA normalization; in group C, 1-month follow-up CEA level decreased less than 35% or increased.
Patients with lower baseline CEA levels had longer overall survival (OS) duration (CEA > 32 vs. 5-32 vs. < 32 ng/mL, OS = 17.8 vs. 22.0 vs. 27.9 months, respectively; p = 0.014). For trend and nadir CEA levels, OS duration was 29.7, 20.0, and 16.2 months in groups A, B, and C, respectively (p < 0.001).
CEA are potential prognostic markers for patients with EGFR-mutant NSCLC treated with first line EGFR-TKIs.
Clinical trial identification
All authors have declared no conflicts of interest.