Prognostic implications of Fas-ligand expression in nasopharyngeal carcinoma

BACKGROUND: In nasopharyngeal carcinoma (NPC), Fas-ligand (Fas-L)-mediated apoptosis might contribute to the immune privilege of tumors. In some cancers, dysregulation of Fas-L protein in tumors might lead to disease progression. The purpose of this study was to evaluate the correlations between Fas-L expression and the clinical outcomes in patients with NPC. METHODS: We recruited 78 patients with primary NPC, classified clinical stages according to the 1997 American Joint Committee on Cancer staging system, and assessed Fas-L with immunohistochemical methods. RESULTS: Forty-one (53%) of 78 patients were Fas-L-positive. The prevalence was 0%, 57%, 58%, and 82% from stages I to IV, respectively (p <.001). Fas-L expression was associated with the N classification (p=.05) but not the T classification. Patients with positive Fas-L expression had a lower rate of disease-free survival and overall survival (p=.01 for all log-rank tests). CONCLUSION: Patients with NPC with Fas-L-positive tumors had higher clinical stages and lymph node metastasis at diagnosis and poorer disease-free survival and overall survival; therefore, Fas-L expression may be a potential biomarker of prognosis.