Abstract
The malignant progression mechanism of precancerous whitish lesions of the vocal cords is still unclear. In this study, the differences of angiogenesis and extracellular matrices between keratosis, dysplasia and invasive carcinoma of the vocal cords were investigated using immunohistochemical staining with anti-CD34, which discerns endothelial cells, and type IV collagen monoclonal antibodies.
In vocal cord keratosis, only a few vessels with small diameters were observed under the basement membrane of the epithelium. An increased number of vessels were recognized around the dysplastic epithelium, downward papillary grow to the stroma. Interestingly, the basement membranes under the dysplastic epithelium and around the vessels were located very closely, suggesting some interaction between the two basement membranes. The double basement membranes were also observed in invasive carcinoma with exophytic growth. In addition, a type IV collagen staining was also seen around nests of carcinoma cells which had infiltrated into the stroma. These results suggest the important roles of the basement membrane and the extracellular matrix in the malignant progression and angiogenesis of the precancerous lesion of the vocal cords.
