Abstract:
Odontogenic neoplasms demonstrate unique histopathological features and are thought to arise from the germinal tissues of the developing tooth germ, effectively restricting their anatomic origin to the tooth-bearing regions of the jaw and directly associated soft tissues of the oral cavity. Ectopic odontogenic-like neoplasms located in the skin of cats, rabbits, and human beings challenge these assumptions. Here we describe the clinical, pathological, and immunohistochemical features of 6 spontaneously occurring odontogenic-like neoplasms arising in the cutaneous tissue of the cheek in client-owned pet rabbits, including ameloblastoma-like (n = 3), ameloblastic fibroma-like (n = 2), and ameloblastic carcinoma-like neoplasms (n = 1). Microscopically, all the cheek tumors featured neoplastic epithelium exhibiting odontogenic architectural structures (plexiform ribbons, anastomosing trabeculae, follicles, cysts, and irregular structures with rounded botryoid protuberances) and 1 or more cardinal odontogenic epithelial features (basal palisading, antibasilar nuclei, and central stellate reticulum-like cells). The pancytokeratin, cytokeratin 5/6, cytokeratin 14, and vimentin immunohistochemical patterns of these odontogenic-like lesions were most similar to those of jaw-associated ameloblastoma and differed from those of cutaneous trichoblastoma. All neoplasms were narrowly excised, and for lesions with clinical follow-up information, none had evidence of recurrence 1-7 months after surgical removal. Although evidence suggests that these odontogenic-like tumors of the rabbit cheek may be derived from ectopic rests of transformed tooth germ, the histogenesis of these lesions remains unresolved.
摘要:
牙源性肿瘤表现出独特的组织病理学特征,被认为是由发育中的牙胚的生发组织产生的,有效地将其解剖起源限制在颌骨的牙齿支撑区域和直接相关的口腔软组织。位于猫皮肤的异位牙源性肿瘤,兔子,人类挑战这些假设。在这里,我们描述了临床,病态,和6种自发发生的牙源性样肿瘤的免疫组织化学特征,这些肿瘤出现在客户拥有的宠物兔的脸颊的皮肤组织中,包括成釉细胞瘤样(n=3),成釉细胞纤维瘤样(n=2),成釉细胞癌样肿瘤(n=1)。微观上,所有脸颊肿瘤都以肿瘤上皮为特征,表现出牙源性建筑结构(丛状丝带,吻合小梁,卵泡,囊肿,和不规则结构,具有圆形的葡萄状突起)和1个或多个主要牙源性上皮特征(基底栅栏,底基底核,和中央星状网状细胞)。Pancytokeratin,这些牙源性样病变的细胞角蛋白5/6,细胞角蛋白14和波形蛋白免疫组织化学模式与颌骨相关成釉细胞瘤最相似,与皮肤成纤维细胞瘤不同。所有肿瘤都被狭窄切除,以及具有临床随访信息的病变,手术切除后1~7个月无复发证据.尽管有证据表明这些兔脸颊的牙源性样瘤可能来自转化的牙胚的异位休息,这些病变的组织发生仍未解决。