Peripheral Ameloblastoma, Rare and Often Misdiagnosed Entity. Case Report and Review of Literature

Peripheral ameloblastoma (PA) is a rare benign odontogenic tumor that accounts for only 2 to 10% of all ameloblastomas. It originates in the soft tissues, typically in the gingiva, and may mimic common reactive lesions, making diagnosis challenging. This paper presents a rare case of peripheral ameloblastoma and reviews the related literature, highlighting diagnostic challenges, histopathological features, and current treatment approaches. A 43-year-old male patient presented with a firm, painless, non-bleeding 3¥3 cm gingival lesion adjacent to the upper right third molar. Radiographic evaluation revealed no bone involvement. A clinical diagnosis of pyogenic granuloma was made, and complete excision was performed along with the extraction of the impacted tooth. Histopathological analysis showed ameloblastomatous epithelium and immunohistochemical positivity for CK19, confirming the diagnosis of peripheral ameloblastoma. Findings were consistent with ameloblastic islands beneath intact squamous epithelium. No bone invasion or malignant transformation was observed. At the two-month follow-up, no recurrence was detected. Peripheral ameloblastoma occurs more frequently in men in their fifth decade and typically affects the mandibular gingiva. Its differential diagnosis includes reactive lesions such as pyogenic granuloma and basal cell carcinoma. Immunohistochemistry, particularly CK19 positivity and Ber-EP4 negativity, is key for differentiation. Although conservative surgical excision is usually effective, cases of recurrence and malignant transformation have been reported, making long-term clinical follow-up essential.

KEY WORDS: Peripheral ameloblastoma; Odontogenic tumor; Differential diagnosis.

EL YACOUBI, O. & TALEB, B. Peripheral ameloblastoma, rare and often misdiagnosed entity. Case report and review of literature. Int. J. Odontostomat., 19(2):109-112, 2025.