Abstract：
OBJECTIVE: Adenoid ameloblastoma (AA) is an epithelial odontogenic tumor that was recognized as a separate entity in the last odontogenic classification of WHO in 2022. The etiology is unknown, and the pathogenesis remains controversial. The objective of this study is to contribute the clinicopathological features of 4 additional BRAF-negative cases to the existing literature, aiming to enhance the molecular understanding of this unique tumor in the forthcoming classification.
METHODS: This study consists of a case series of four patients diagnosed with AA. The patients\' demographic and clinical information were collected from the universities\' medical achieves. Histopathologically, all cases were reexamined according to the latest update of the WHO odontogenic tumor classification. In addition to H&E and immunohistochemical stains, cytogenetics was also evaluated.
RESULTS: Well-defined unilocular radiolucent lesions were observed in all cases. Ameloblastoma-like components exhibited reserved nuclear polarity, suprabasal stellate reticulum-like epithelium, duct-like structure, whorls/morules, and cribriform architecture were common features. Variable immunoreactivity to CK7, CK19, CK14, p63, and p40 were determined, and proliferative activity was greater than 15%. The BRAF molecular study revealed no mutations.
CONCLUSIONS: When diagnosing AA, the essential histopathological characteristics must be rigorously applied, and a significant portion of the lesion should contain these features. Additionally, despite limited molecular data, since the BRAF mutation commonly observed in ameloblastomas is not present in the majority of AA cases, we propose changing the term \"ameloblastoma\" to \"ameloblastic\" and referring to it as \"adenoid ameloblastic tumor\" in the forthcoming classification.
METHODS: This study consists of a case series of four patients diagnosed with AA. The patients\' demographic and clinical information were collected from the universities\' medical achieves. Histopathologically, all cases were reexamined according to the latest update of the WHO odontogenic tumor classification. In addition to H&E and immunohistochemical stains, cytogenetics was also evaluated.
RESULTS: Well-defined unilocular radiolucent lesions were observed in all cases. Ameloblastoma-like components exhibited reserved nuclear polarity, suprabasal stellate reticulum-like epithelium, duct-like structure, whorls/morules, and cribriform architecture were common features. Variable immunoreactivity to CK7, CK19, CK14, p63, and p40 were determined, and proliferative activity was greater than 15%. The BRAF molecular study revealed no mutations.
CONCLUSIONS: When diagnosing AA, the essential histopathological characteristics must be rigorously applied, and a significant portion of the lesion should contain these features. Additionally, despite limited molecular data, since the BRAF mutation commonly observed in ameloblastomas is not present in the majority of AA cases, we propose changing the term \"ameloblastoma\" to \"ameloblastic\" and referring to it as \"adenoid ameloblastic tumor\" in the forthcoming classification.
摘要：
目的：腺样体成釉细胞瘤（AA）是一种上皮牙源性肿瘤，在2022年WHO的上一次牙源性分类中被认为是一个单独的实体。病因不明,发病机制仍存在争议。本研究的目的是为现有文献贡献另外4例BRAF阴性病例的临床病理特征，旨在在即将到来的分类中增强对这种独特肿瘤的分子理解。
方法：本研究由4例确诊为AA的患者组成。患者的人口统计学和临床信息是从大学医学成就中收集的。组织病理学,根据WHO牙源性肿瘤分类的最新更新,对所有病例进行了重新检查.除了H&E和免疫组织化学染色，还评估了细胞遗传学。
结果：在所有病例中均观察到明确定义的单眼射线可透病变。成釉细胞瘤样成分表现出保留的核极性，鼻上星状网状上皮，管道状结构，螺纹/modules，和筛形建筑是共同的特征。测定了对CK7，CK19，CK14，p63和p40的可变免疫反应性，增殖活性大于15％。BRAF分子研究显示没有突变。
结论：诊断AA时，必须严格应用基本的组织病理学特征，病变的很大一部分应该包含这些特征。此外,尽管分子数据有限，由于在成釉细胞瘤中常见的BRAF突变在大多数AA病例中不存在，我们建议将术语“成釉细胞瘤”改为“成釉细胞瘤”，并在即将到来的分类中将其称为“腺样体成釉细胞瘤”。
方法：本研究由4例确诊为AA的患者组成。患者的人口统计学和临床信息是从大学医学成就中收集的。组织病理学,根据WHO牙源性肿瘤分类的最新更新,对所有病例进行了重新检查.除了H&E和免疫组织化学染色，还评估了细胞遗传学。
结果：在所有病例中均观察到明确定义的单眼射线可透病变。成釉细胞瘤样成分表现出保留的核极性，鼻上星状网状上皮，管道状结构，螺纹/modules，和筛形建筑是共同的特征。测定了对CK7，CK19，CK14，p63和p40的可变免疫反应性，增殖活性大于15％。BRAF分子研究显示没有突变。
结论：诊断AA时，必须严格应用基本的组织病理学特征，病变的很大一部分应该包含这些特征。此外,尽管分子数据有限，由于在成釉细胞瘤中常见的BRAF突变在大多数AA病例中不存在，我们建议将术语“成釉细胞瘤”改为“成釉细胞瘤”，并在即将到来的分类中将其称为“腺样体成釉细胞瘤”。
