Expression of Maspin in Non-Small-Cell Lung Cancer: Correlation with Clinical Features

Purpose: Maspin is a member of the serpin (serine protease inhibitor) family and has been shown to be a suppressor of tumor growth and metastasis in several types of tumors. The objective of this study was to evaluate whether maspin is a prognostic factor in patients with non-small-cell lung cancer (NSCLC). Patients and Methods: We investigated maspin expression in 181 patients with curatively resected NSCLC by means of immunohistochemistry. We also determined whether expression of maspin correlates with the microvessel density (MVD) level. Results: The incidence of strong maspin expression in patients with squamous cell carcinoma was significantly higher than that in patients with other histology (46 of 70 [65.7%]; P < .0001). There was no significant difference between maspin expression status and MVD. Prognosis was defined as progression-free survival (PFS) and overall survival (OS). There was no difference in PFS or OS between patients with strong and weak maspin expression among all patients. However, for squamous cell carcinoma, the PFS and OS rates for patients with strong maspin expression were significantly higher than those for patients with weak maspin expression (PFS, P = .004; OS, P = .001). In multivariate analysis on squamous cell carcinoma, strong maspin expression was an independent favorable prognostic indicator (PFS, P = .03; OS, P = .01). Conclusion: Strong maspin expression was an independent factor in predicting a favorable prognosis in squamous cell carcinoma of lung.