Cellular features in desmoid fibromatosis and well-differentiated fibrosarcomas: an electron microscopic study.

In the study presented here the ultrastructural cellular features of three desmoids and four well-differentiated fibrosarcomas were compared. Electron microscopically, the tumors were almost identical relative to qualitative traits. The majority of cells corresponded to fibroblast-like cells with certain morphological variations. Especially cells with characteristics of myofibroblasts must be emphasized, whereas cells with an organelle composition of classical fibroblasts were surprisingly seldom. Considering the relations of cells to each other and to vessels the prevailing origin of tumor cells from preexisting fibroblasts is suggested.