Adenomatoid odontogenic tumor—Report of a posterior mandibular case with the presence of ghost cells

Adenomatoid odontogenic tumor (AOT) occurs more frequently in the maxillary anterior region. Recurrence of AOT after surgical excision is very rare. In this case report, we describe a left posterior mandibular AOT case that exhibited three recurrences after surgical removal. A 25-year-old female patient was first seen by an oral surgeon in a regional hospital with the chief complaint of a swelling at the left mandibular molar region. The tumor was removed by enucleation. Five years later, the tumor recurred at the same region. The patient was referred to our hospital for treatment, and the recurrent tumor was widely excised. The pathological report was an extrafollicular AOT. Eleven years later, the tumor recurred again. It was removed using segmental mandibulectomy with titanium plate reconstruction. The pathological report was also an extrafollicular AOT. Nine months later, the mandibular bone defect was further reconstructed by a segment of iliac bone graft fixed by a new titanium plate and screws. Twenty-eight years after the initial surgery, the tumor recurred again in the alveolar mucosa covering the graft bone. It was further excised, and the pathological report was a peripheral AOT with the presence of amyloid materials and globules of ghost cells. Our AOT case recurred thrice after two conservative excisions and one more radical surgical resection. The multiple recurrences of the tumor indicate the importance of initial complete resection of the tumor. In addition, our case may represent the first reported AOT with the presence of ghost cells in the tumor tissue.