Abstract
BACKGROUND: Despite surgical resection, the prognosis for patients with non-small cell lung cancer (NSCLC) remains unsatisfactory. The objective of this study was to investigate the impact of serum carcinoembryonic antigen (CEA) levels on recurrence in patients with NSCLC before and after surgical resection. In addition, for patients with invasive lung adenocarcinoma (IAC), which constitutes the majority of cases, we further explored the effect of pathological subtype on recurrence. METHODS: A total of 349 patients were included in the study. The correlation between clinicopathological factors and post-surgery survival outcomes was analyzed. Kaplan-Meier curves were constructed based on the pertinent data and analyzed using the Cox regression model. Recurrence risk curves were plotted according to the time to recurrence for each CEA subgroup and pathological subtype to explore the change in recurrent rate over time in each group. RESULTS: A total of 9 (81.82%) patients in the low preoperative CEA but higher than normal postoperative CEA levels group experienced recurrence, with a median recurrence-free survival (RFS) of only 24 months and a median overall survival (OS) of 57 months. These outcomes demonstrated poorer RFS and OS than those observed in the other three groups. Multivariate analysis of RFS revealed postoperative CEA level (P<0.001), histological type (P=0.01), tumour size (P=0.048), tumor-node-metastasis (TNM) stage (P<0.001) and pN stage (P=0.04) as independent poor prognostic factors. postoperative CEA level (P=0.003), histological type (P=0.02), tumor size (P=0.03), TNM stage (P=0.004) and pN stage (P=0.049) were independent poor prognostic factors for OS. Among the pathological subtypes, patients with Grade 3 (high-grade patterns ≥20%) exhibited a higher risk of recurrence after surgery. CONCLUSIONS: Elevated CEA levels in the postoperative period, as well as pathological subtypes of Grade 3, have been identified as risk factors for early recurrence in NSCLC patients after surgery.