A case of secondary ameloblastic carcinoma of the mandible and a comparative review of primary and secondary subtypes.

BACKGROUND

Ameloblastic carcinoma is an extremely rare malignant odontogenic epithelial tumor, which can be categorized into primary ameloblastic carcinoma and secondary ameloblastic carcinoma. The secondary type typically arises from a pre-existing, histologically confirmed benign ameloblastoma. Owing to the scarcity of clinical reports, the epidemiology, treatment, and prognosis of ameloblastic carcinoma remain poorly understood.

METHODS

We report and analyze a case of a 49-year-old male with secondary ameloblastic carcinoma of the mandible. Based on preoperative pathological examination indicating squamous cell carcinoma, the patient underwent right mandibular resection, cervical lymph node dissection, and anterolateral femoral flap repair. Postoperatively, the diagnosis of secondary ameloblastic carcinoma was confirmed pathologically. No signs of metastasis or recurrence were observed during the 2-year follow-up. Additionally, we systematically reviewed the literature on the clinical details, treatment, and outcomes of ameloblastic carcinoma from 2000 to 2022, including five cases from our hospital.

RESULTS

A total of 35 cases of primary ameloblastic carcinoma and 45 cases of secondary ameloblastic carcinoma were identified. Both types predominantly occur in males, primarily in the mandible, and are mainly treated with surgery. However, they present at different ages. The primary type is characterized by a short disease course and a favorable prognosis, whereas the secondary type usually has a history of ameloblastoma and a poor prognosis.

CONCLUSION

Our study is one of the few in the literature to highlight a high incidence of secondary ameloblastic carcinoma, suggesting that clinicians should be vigilant for malignant transformation in benign ameloblastomas. We hope this research provides valuable insights for clinical management and a theoretical basis for future studies on the pathogenesis of ameloblastic carcinoma.