Ameloblastic fibrosarcoma: an ultrastructural study of the mesenchymal component

The mesenchymal components of tumors from 2 patients with ameloblastic fibrosarcoma were studied ultrastructurally. The mesenchymal components consisted predominantly of fibroblastic cells with a few histiocytic or fibrohistiocytic cells and myofibroblastic cells. In addition, a very small number of undifferentiated mesenchymal cells were found. We speculate that the mesenchymal components in this tumor may be derived from the undifferentiated mesenchymal cells.