Relation between lymphatic vessel diameter and clinicopathologic parameters in squamous cell carcinomas of the oral region

Abstract

In an attempt to determine the mechanism of cervical lymph node metastases, the authors studied the relation between lymphatic vessels in or around tumour tissue and lymph node metastases in patients with primary squamous cell carcinoma (SCC) of the oral region by enzyme histochemistry using 5′ nucleotidase-alkaline phosphatase. The subjects consisted of 23 patients, who had biopsy proven oral SCC. After enzyme histochemical staining, the cross-sectional dimensions of the lymphatic vessels were measured and analysed in relation to the T classification of the tumour, degree of tumour differentiation and mode of invasion. The average diameter of the lymphatic vessels in or around tumour tissue was significantly greater than that in tumour-free tissue (P<0.01). The mode of invasion correlated significantly with the lymphatic vessel diameter (P<0.01). The diameter did not correlate significantly with the T classification (P range, 0.135–0.254) or tumour differentiation (P=0.274). The following relation was found between the incidence of cervical lymph node metastases and the mode of invasion: 40.0% of Grade 2 tumours were positive for metastases, 71.4% of Grade 3 tumours were positive, and 75.0% of Grade 4 tumours were positive (grading was according to Jakobsson’s classification). Of the factors evaluated in this study, only the mode of invasion correlated significantly with the diameter of the lymphatic vessels. Although other studies have shown that tumour thickness and perhaps even perineural and blood vessel invasion may be equally important, the findings of the current study suggest that both lymphatic vessel diameter and the mode of invasion may be important factors in the prediction of cervical lymph node metastases. Henk Tideman