Epithelial-mesenchymal transition: clinical implications for nodal metastasis and prognosis of tongue cancer.

OBJECTIVE: The development of biomarkers for the prediction of lymph node metastasis and prognosis is critical for deciding the treatment modality of tongue cancer. The purpose of our study is to investigate the clinical implications of epithelial-mesenchymal transition (EMT) expression in tongue cancer. STUDY DESIGN: Historical cohort study SETTING: Tertiary-care hospital. SUBJECTS AND METHODS: The study included 95 subjects with tongue cancer who underwent wide excision and neck dissection. According to characteristics of immunohistochemical staining for E-cadherin and vimentin, we classified the tumors as complete EMT phenotype, incomplete EMT phenotype, or epithelial phenotype. The correlation between risk factors and nodal metastasis was assessed, and disease-free survival (DFS) was analyzed. RESULTS: Positive lymph nodes were detected in 46 (48.4%) patients and was found to correlate significantly with depth of invasion >/= 4 mm and EMT expression on multivariate analysis (P = .030, P = .022, respectively). The mean follow-up period of all patients was 96.3 months (range, 6-149 months). Overall 5-year DFS was 61.7%. On multivariate analysis, the only factors affecting DFS were nodal stage and EMT expression (P = .033, P = .021, respectively). CONCLUSIONS: Our study reveals that EMT expression is a significant biomarker for predicting lymph node metastasis and tumor recurrence in tongue cancer. Evaluation of EMT expression in tongue cancer can allow therapy to be offered accordingly.