Staging of oral squamous cell carcinoma is based on the TNM system, which has been deemed insufficient for prognostic purposes. Hence, better prognostic tools are needed to reflect the biological diversity of these cancers. Previously, high numbers of specialized blood vessels called high-endothelial venules have been reported to be associated with prolonged survival in patients with breast cancer. In this study, we analysed the prognostic value and morphological characteristics of

more »

... ated high-endothelial venules in oral cancer. Methods: The presence of tumour-associated high-endothelial venules was evaluated by immunohistochemistry in 75 patients with oral squamous cell carcinoma and analysed with correlation to clinicopathological parameters, patients' survival, and vessel morphology. Ten of the samples were analysed at multiple levels to evaluate intratumoural heterogeneity. Results: The presence of tumour-associated high-endothelial venules was found to be associated with lower disease-specific death in multivariate regression analyses (P=0.002). High-endothelial venules were present in all (n=53) T1-T2 tumours, but only in two-thirds (n=14) of the T3-T4 tumours. The morphology of high-endothelial venules was heterogeneous and correlated with lymphocyte density. High-endothelial venules were found to be distributed homogeneously within the tumours. Conclusion: We found the presence of tumour-associated high-endothelial venules to be an easy-to-use, robust, and independent positive prognostic factor for patients with oral cancer. Absence of these vessels in advancedstage tumours might identify patients with more aggressive disease. Evaluating the presence of tumour-associated high-endothelial venules might help to tailor the treatment of oral cancer patients to their individual needs.