Size, shape, structure, and direction of angiogenesis in laryngeal tumour development.

AIMS Angiogenesis and vessel organisation in laryngeal tumour development and progression were examined to determine characteristics of biological and clinical relevance. METHODS Automated quantitative image analysis was performed on 1451 factor VIII (FVIII) associated blood vessels with regard to occurrence, structure, size, shape, and staining intensity, in addition to vessel direction. RESULTS Vessel numbers were increased in preneoplastic states and severe dysplasia, in addition to squamous cell carcinomas, being greater in poorly differentiated carcinomas. Small regular vessels predominated in benign conditions and large, irregular vessels in malignant neoplasms. Vessel distribution was related to degree of differentiation in squamous cell carcinomas, with circumferential angiogenesis occurring in well differentiated neoplasms, directional angiogenesis in moderately differentiated tumours, and aberrant angiogenesis in less well differentiated neoplasms. Alterations in vessel shape increased significantly with increasing degree of malignancy. Comparing the characteristics of individual vessels showed vessel shape abnormalities and the intensity of FVIII staining to increase with vessel size. CONCLUSIONS Increased angiogenesis was an early event in laryngeal tumour development, with vessel structure, size, and shape related to the tumour growth pattern and behaviour.