Correlation between lymphatic vessel density and regional metastasis in squamous cell carcinoma of the tongue.

BACKGROUND The aim of this study was to investigate the correlation between lymphatic vessel density in squamous cell carcinoma of the tongue and regional metastasis. METHODS Intratumoral and peritumoral lymphatic densities (ILDs and PLDs, respectively) were determined by immunohistochemical staining of lymphatic endothelial cells with podoplanin in 62 patients surgically treated for tongue cancer. Clinicopathological variables were quantified, and their correlations with regional metastasis were assessed. RESULTS The rate of regional metastasis was significantly higher in patients with high ILD than that in those with low ILD (21/33, 63.6% vs 8/29, 27.5%; p = .006). Perineural invasion and lymphovascular invasion were also significantly correlated with regional metastasis. By multivariate analyses, ILD was the only variable identified to be significantly correlated with regional metastasis (p = .009). On the other hand, PLD showed no correlation with regional metastasis. CONCLUSIONS ILD showed a strong correlation with regional metastasis in patients with squamous cell carcinoma of the tongue.