Ameloblastic carcinoma of the mandible: A case report and literature review

Abstract

Ameloblastic carcinoma is a rare malignant odontogenic tumor. Here we present a case of malignant transformation of ameloblastoma into ameloblastic carcinoma over a period of eight years. A cystic lesion in the left mandible was initially identified histopathologically as ameloblastoma, and curettage of the lesion was performed. Recurrence occurred 7 years later, and was treated with a second enucleation and curettage of the tumor. The second histopathological diagnosis was also ameloblastoma. One year later the patient presented with a swelling on the left side of the retromolar triangle. An incisional biopsy detected cytological atypia, and the histopathological features met the criteria for diagnosis of ameloblastic carcinoma. Surgical treatment with segmental mandibulectomy and reconstruction with a free vascularized fibula bone graft was performed. A literature review was performed identifying a total of 234 cases of ameloblastic carcinoma reported. The median age of onset was 47 years, with a peak incidence during the third- and sixth decades. A predominance of men was found, with a male-female ratio of 2,21:1. The tumor was more frequently reported in the mandible, with a mandible-to- maxilla ratio of 1,96:1, and the most common tumor site was the posterior mandible. Surgical treatment was the primary treatment modality and was performed in 87,2% of the patients. Recurrence was reported in 22,2% of the patients, and metastasis in 18,8%. The most common sites for metastasis were the lungs, followed by regional lymph nodes and the brain.