Prognostic significance of histologic differentiation, carcinoembryonic antigen value, and lymphovascular invasion in stage I non-small cell lung cancer

Objective: For stage I non-small cell lung cancer (NSCLC), the only 2 prognostic factors incorporated into the seventh edition of the TNM staging system were tumor size and visceral pleural invasion. However, with this staging system, the prognostic precision of survival has proved elusive, suggesting the need to include additional prognostic factors. To improve prognostic applications and treatment decisions, we investigated clinicopathologic factors affecting progression-free survival in patients with surgically resected stage I NSCLC. Methods: From January 2004 to December 2011, we retrospectively reviewed the clinicopathologic characteristics of 758 consecutive patients with surgically resected stage I NSCLC at the National Taiwan University Hospital. Results: The 5-year progression-free survival rate was 82.3% and 64.0% for those with stage IA (n = 481) and stage IB (n = 277), respectively. Multivariate analysis revealed poor or moderate histologic differentiation and elevated preoperative serum carcinoembryonic antigen were statistically significant risk factors for recurrence in patients with stage IA. Poor or moderate histologic differentiation, elevated preoperative serum carcinoembryonic antigen, lymphovascular invasion, and tumor size > 2 cm were statistically significant risk factors for recurrence in patients with stage I NSCLC. The 5-year progression-free survival rate was 93.0%, 73.8%, and 40.6% for stage I patients with no, 1 or 2, and > 2 risk factors, respectively (P <. 001). Conclusions: In addition to tumor size, we identified 3 other independent risk factors for recurrence in patients with stage I NSCLC. These 3 risk factors warrant consideration as additional predictors in the next version of the TNM staging system.