Late recurrence more than 40 years of mandibular ameloblastoma: Report of two cases

Ameloblastoma is a benign odontogenic tumor with a relatively high incidence. However, there are few case reports of ameloblastoma recurring after more than 30 years, and there are no reports of recurrence after 50 years. Here we report 2 cases of recurring ameloblastoma, one after 40 years and the other after 50 years, and we discuss the differences in clinical features and treatment between early recurrent cases (<20 years) and late recurrent cases (>20 years) on the basis of a literature review. There was no difference in occurring site or histologic type, and all late recurrent ameloblastomas occurred on the mandible, with follicular being the most common histologic type. However, there was a difference in treatment methods. Marginal resection or wide resection was performed in most late recurrent cases, and no conservative treatment was performed. Ameloblastoma should be followed-up with consideration of the potential for recurrence over the long term.