Prognostic relevance of CD105+ microvessel density in HNSCC patient outcome

Angiogenesis is essential for the development and progression of malignant tumours, and there is increasing evidence that microvessel density (MVD) can be considered an indirect marker of neo-angiogenesis. However, there is still disagreement concerning the clinical relevance and prognostic significance of MVD in head and neck squamous cell carcinomas (HNSCCs). MVD was evaluated in 127 HNSCC patients by means of immunohistochemistry using monoclonal antibodies (mAbs) against CD34 and CD105 (endoglin), which has recently been described as a potent marker of neo-vascularisation in various malignancies. MVD was expressed as the mean number of vessels/mm2. The mean CD34+ and CD105+ MVD values were significantly higher in T3-T4 tumours and those in an advanced clinical stage; furthermore, CD105+ MVD was significantly higher in N+ tumours. The patients with a high CD105+ MVD had a significantly shorter disease-free and overall survival; CD34+ MVD was not associated with survival. Similarly, in the subset of lymph-node negative patients, higher CD105+ MVD values were significantly associated with either OS and DFS. Multivariate analysis showed that a high CD105+ MVD was the only independent marker of tumour recurrence or death. Our data suggest that CD105+ MVD may represent an additional prognostic factor in HNSCC patients providing more accurate data for the determination of prognosis and management in the subset of lymph node negative patients.