[Peripheral ameloblastic fibrosarcoma]

We describe the clinicopathological features of a peripheral ameloblastic fibrosarcoma (PAFS) diagnosed in a 89-years-old man with a past history of recurrent peripheral ameloblastoma. Like other peripheral odontogenic tumors, PAFS shows histological features comparable to those of the central intraosseous form, with (fibro)sarcomatous proliferation associated to benign-appearing ameloblastomatous areas. The differential diagnosis must be made with a low-grade spindle ameloblastic carcinoma and with a collision tumor (a non odontogenic sarcoma associated with a recurrent ameloblastoma). Almost any odontogenic tumor has been observed in the peripheral soft tissues, but our case seems to be, to our best knowledge, the first case of PAFS reported in the literature. This fact can only reflect the rarity of its central counterpart. A particular feature is the old age of our patient (ameloblastic fibrosarcoma usually occurs in adolescent or young adult). Another particular feature is that this PAFS appeared in the contiguity of a recurrent peripheral ameloblastoma. As proposed by many authors, this finding suggests that peripheral odontogenic tumors should require a long-term follow-up and, maybe, a more aggressive initial surgical management.