Microvessel Density, Thymidine Phosphorylase Expression and Resistance of Head and Neck Cancer to Chemo-Radiotherapy

Cancer growth, invasion and metastasis is strongly dependent on the angiogenic ability. A growing amount of clinicopathological studies confirms that intratumoural microvessel density (MVD) is one of the strongest prognostic variables in human cancer. However, vasculature is also related to the amount of haemoglobin that reaches the tumour, thus oxygenation. Moreover, during chemotherapy, the vessel density strongly defines the drug availability to the tumour. Since euoxic conditions are related to a higher response to radiotherapy (RT) and high drug availability to higher chances for the tumour to respond to chemotherapy, it would be suggested that high microvessel density is a marker of a better response to cytotoxic therapy.