To clarify the correlation between tumor angiogenesis and tumor growth in head and neck carcinomas, we investigated the number of microvessels, using immunohistochemical factor VIII. No correlations among this number, differences in the primary lesion, histological differentiation and T classification were detected. The incidence of neck lymph node metastases increased as microvessel numbers increased in tumor sites. The number of microvessels increased as N and Stage classification progressed. The number of microvessels in CR cases after induction chemotherapy were increased. The numbers of microvessels in patients without recurrence were apparently greater than those in patients with recurrence. The results of this study suggest that the number of microvessels in a primary tumor correlates with the metastatic ability of the tumor.