Andrew P. Collins, Naser Mubarak, Hadi S. Hemaidan, Sami M. Hemaidan, Ammar Hemaidan
College of Medicine, University of Central Florida, Orlando, FL, USA
Am J Case Rep 2021; 22:e929422
Available online: 2021-05-20
Primary malignant ameloblastoma is a very rare tumor of the dental lamina epithelium. Similar to the benign ameloblastoma, the mass is without significant histological atypia, but the malignant type may present with metastases, most commonly to the lungs. The average age of diagnosis is 34 years, and the malignancy affects men and women equally. The tumors often present with an insidious growth and have a median survival from time of diagnosis of 17.6 years. Due to the rarity of this lesion, a standard of care has not yet been established.
CASE REPORT: A 38-year-old Haitian woman, who initially presented with a large primary malignant ameloblastoma of the angle of the mandible, experienced a recurrence in the floor of the mouth 30 months after surgical resection. In 2018, 2 years after the removal of the recurrent tumor, the patient presented with ascites, right-sided abdominal pain, weight loss, and a palpable liver mass. Laparoscopic exploration demonstrated a complex lateral right liver lobe cyst, suspicious for parasitic infection. Cytological analysis showed positive staining for cytokeratin 5/6, P63, and CD56, indicative of metastatic ameloblastoma of the liver. Consistent cell morphology from the primary tumor and liver cyst was also noted. Following drainage of the cyst, the patient returned to Haiti, where she died in 2020. In Haiti, she lacked appropriate local medical care, leading to the severe progression of her initial primary ameloblastoma and disease recurrence.
CONCLUSIONS: Malignant ameloblastoma accounts for less than 2% of all odontogenic tumors, as the benign variant is much more common. Distant metastases of these lesions are rare; to date, few cases have presented with hepatic metastases.
Keywords: Ameloblastoma, Neoplasm Metastasis, Rare Diseases