Prognostic factors based on clinicopathological data among the patients with resected peripheral squamous cell carcinomas of the lung

Introduction: Although the incidence of peripheral squamous cell carcinomas (p-SqCCs) of the lung has increased over recent years, clinicopathological factors influencing prognosis of resected p-SqCCs remain unclear. Methods: We examined 280 patients who underwent complete resection of SqCCs and analyzed the clinicopathological features in relation to their overall survival (OS) and recurrence-free survival (RFS) according to the primary location. Results: Multivariate analysis of all stages of p-SqCCs patients revealed that high serum squamous cell carcinoma antigen (SCC) level (OS; p < 0.01, RFS; p < 0.01), vascular invasion (OS; p < 0.01, RFS; p < 0.01), pleural invasion (OS; p = 0.03, RFS; p = 0.01), nodal metastasis (OS; p = 0.02) and complication with lung disease (OS; p < 0.01) were independently unfavorable prognostic factors. Among stage I p-SqCCs patients, high serum SCC level (OS; p < 0.01, RFS; p < 0.01), vascular invasion (RFS; p < 0.01) and pleural invasion (RFS; p = 0.01) were also strongly correlated with poor prognosis independently. When we reevaluated the survival rate, T1 p-SqCCs with high serum SCC level or vascular invasion can be upgraded to T2a. Patients with stage IB had a significantly poorer prognosis than stage IA (5-year RFS; 61.4 % versus 76.6 %, p < 0.05). Conclusion: High serum SCC level, pleural and vascular invasions were independent poor prognostic factors for completely resected p-SqCCs. T1 p-SqCCs with high serum SCC level or vascular invasion should be upgraded to T2a, which accurately reflect survival status among patients with p-SqCCs.