Peripheral extraosseous ameloblastoma is the rarest subtype of ameloblastoma, accounting for 1-2% of cases. We report a case in which a peripheral ameloblastoma of the acanthomatous type occurred at the same site of a previously removed central ameloblastoma.
The patient had a central ameloblastoma of the right mandibular angle removed 15 years ago. The patient underwent clinical and radiological follow-up, initially every six months and then every year, which ended eight years ago. On the advice of her family dentist, the patient presented again with an exophytic mucosal change in the area of the former resection site. A sample was taken and a histological examination was performed, which revealed a peripheral ameloblastoma of the acanthomatous type; a microscopically complete removal could not be assumed due to marginal cell nests.
Due to the rarity of the findings, there is no clear consensus regarding the necessary radicality of the removal. In this case, a subsequent resection was dispensed with in favour of close clinical and radiological follow-up; a six-monthly follow-up interval was again specified.