Recurrence of unicystic ameloblastoma: a case report and review of the literature.

Unicystic ameloblastoma is believed to be less aggressive and responds more favorably to conservative surgery than the solid or multicystic ameloblastomas. We report a case of unicystic ameloblastoma that was initially treated by marsupialization and later by enucleation under suspicion of a dentigerous cyst. The neoplastic nature of the lesion became evident only when the enucleated material was available for histologic examination. Apart from an ameloblastomatous epithelial lining and luminal tumor nodules, the cystic tumor contained numerous tumor islands within its fibrous capsule. The lesion recurred 8 years after the enucleation. This case supports the view that the presence of tumor islands in the fibrous capsule may indicate a high risk of recurrence for unicystic ameloblastomas. Relevant diagnostic problems and choice of treatment are presented along with a review of the literature.