de Gracia Hahn D, Gupta G, Mukhopadhyay S, Greaney L
Histopathology Department, Charing Cross Hospital, Imperial College Healthcare NHS Foundation Trust, London, UK.
Histopathology Department, Charing Cross Hospital, Imperial College Healthcare NHS Foundation Trust, London, UK.
Int J Oral Maxillofac Surg. 2025 Aug;54(8):695-700. doi: 10.1016/j.ijom.2025.02.010. Epub 2025 Mar 17.
Ameloblastic fibroma is a rare, benign, biphasic odontogenic tumour that typically presents in young patients and is treated conservatively with an excellent prognosis. An important differential is ameloblastoma, a more common odontogenic neoplasm that shares many of the clinical, radiological, and histological features, but requires more extensive surgery due to its potentially destructive nature. Both tumours demonstrate BRAF V600E mutations. While epithelial staining with BRAF V600E-specific immunohistochemistry is considered a surrogate marker for mutation and is supportive of the diagnosis of ameloblastoma, the staining pattern in ameloblastic fibroma has not been defined previously because of the rarity of the lesion. This report describes a case of ameloblastic fibroma in a 13-year-old, in which BRAF V600E immunohistochemistry showed cytoplasmic staining in both the stromal and epithelial components of the tumour. On review of the literature, this was interpreted to be concordant with the biphasic nature of the lesion.
成釉细胞纤维瘤是一种罕见的、良性的、双相性牙源性肿瘤，通常发生于年轻患者，采用保守治疗，预后良好。一个重要的鉴别诊断是成釉细胞瘤，它是一种更常见的牙源性肿瘤，具有许多临床、放射学和组织学特征，但由于其潜在的破坏性，需要更广泛的手术。这两种肿瘤均显示BRAF V600E突变。虽然BRAF V600E特异性免疫组化的上皮染色被认为是突变的替代标志物，支持成釉细胞瘤的诊断，但由于成釉细胞纤维瘤病变罕见，其染色模式此前尚未明确。本报告描述了一例13岁的成釉细胞纤维瘤病例，其中BRAF V600E免疫组化显示肿瘤的基质和上皮成分均有细胞质染色。经文献复习，这被解释为与病变的双相性一致。
