Tibial adamantinoma: its histogenesis from ultrastructural studies.

Only three previous reports on the ultrastructural appearance of tibial adamantinoma have been found among some 120 cases of this tumor reported in the literature. The tumor in our case is less differentiated than the cases previously reported. We believe it is of epithelial character and the possibilities of its histogenesis have been narrowed down to either mesothelial, synovial or squamous origins among the many theories proposed. Ameloblastic origin, however, cannot be ruled out.