[Ultrastructure of the terminal vessels in squamous cell carcinoma of the human external ear. A transmission electron microscopy study].

Electron microscopic findings of vascular fine structure of the squamous cell carcinoma of the human auricle are reported. According to morphological criteria, the tissue was divided into three areas: non-infiltrated zone, transitional zone and centre of the tumor. In the non-infiltrated zone the vessels reveal the pattern of normal vessels of the skin. In the transitional zone endothelial cells bearing all signs of newly formed vessels can be detected as well as endothelial cells that show structural characteristics of severe cellular damage. In the tumour centre itself vessels are found with fenestrations and even true endothelial gaps. Interstitially located RBCs imitate the former outline of the vascular lumen. The observations are discussed and compared with the relevant literature.