Prediction of delayed neck metastasis in patients with stage I/II squamous cell carcinoma of the tongue

BACKGROUND: The incidence of delayed neck metastasis (DNM) in patients with squamous cell carcinoma (SCC) of the tongue is reported to be 20% to 50%. Although clinically negative cervical lymph nodes (N0) are associated with a good outcome, the prognosis is poor in patients with DNM. The aim of this study was to evaluate the clinicopathological and immunohistochemical parameters associated with DNM in patients with stage I/II SCC. METHODS: Fifty nine patients, with previously untreated stage I/II carcinoma, underwent examination of clinicopathological and immunohistochemical parameters and incidence of DNM. A linear discriminant analysis was used to analyze prognostic factors and to determine the probability of DNM occurring. RESULTS: DNM occurred in 14 (24%) subjects of the 59 study patients, level I to level III, within 5 years. Parameters such as gender and age, disease stage, tumor size and histological grade, tumor location, degree of tumor invasion and expression of VEGF, E-cadherin or Ki-67 showed no significant correlation with the occurrence of DNM; however, factors such as tumor morphology, tumor thickness greater than 4 mm, and Flt-4 expression were significantly associated with development of DNM. CONCLUSIONS: Such factors provide useful information with regard to DNM and the prognosis. We concluded that patients with early SCC whose tumors are > 4 mm in thickness and immunopositive for Flt-4 are particularly at risk of developing DNM.