皮脂腺肿瘤是起源于皮脂腺的肿瘤,是第三常见的皮肤肿瘤,占狗所有皮肤肿瘤的21-35%。根据它们的组织病理学特征,皮脂腺肿瘤可分为良性腺瘤和恶性上皮瘤。皮脂腺上皮瘤与皮脂腺瘤的区别在于含有90%或更多的储备细胞。然而,这个简单的数值标准不足以在组织学上区分上皮瘤和腺瘤.此外,人类的皮球瘤,类似于皮脂腺上皮瘤的肿瘤,是一个术语,用于具有超过50%的储备细胞的肿瘤,不像上皮瘤.因此,我们旨在比较和表征综合皮脂腺腺瘤的组织学和免疫组织化学特征,上皮瘤,和具有超过50%但不到90%的储备细胞的交界性肿瘤。共有14个犬皮脂腺肿瘤被诊断为7个腺瘤,四个交界性肿瘤,还有三个上皮瘤.组织学上,皮脂腺腺瘤显示结节由单层基底细胞包围的成熟皮脂腺细胞组成。相比之下,储备细胞的部分增加了,脂肪化细胞的部分减少,在皮脂腺上皮瘤中发现大多数脂肪化细胞是不成熟的。在皮脂腺腺瘤中,未观察到坏死,很少见到有丝分裂图。然而,在交界性肿瘤和皮脂腺上皮瘤中,坏死和有丝分裂现象非常常见。免疫组化显示,交界性肿瘤和皮脂腺上皮瘤对Ki-67的表达明显高于皮脂腺腺瘤。我们得出的结论是,在人类中使用50%的储备细胞的临界值而不是目前的90%的储备细胞来分类狗的皮脂腺肿瘤更准确。从而为皮脂腺肿瘤的表征提供了新的见解。
Sebaceous gland tumors are neoplasms originating from the sebaceous gland and are the third most common type of skin tumor, accounting for 21-35% of all cutaneous neoplasms in dogs. According to their histopathological characteristics, sebaceous gland tumors can be classified into adenoma as a benign tumor and epithelioma as a malignant tumor. Sebaceous
epithelioma is distinguished from sebaceous adenoma by containing 90% or more reserve cells. However, this simple numerical criterion is insufficient to histologically distinguish between epitheliomas and adenomas. In addition, sebaceoma in humans, a similar tumor to sebaceous
epithelioma, is a term used for tumors with more than 50% of reserve cells, unlike
epithelioma. Therefore, we aimed to compare and characterize the histological and immunohistochemical profiles of comprehensive sebaceous adenoma,
epithelioma, and borderline tumors that have more than 50% but less than 90% of reserve cells. A total of 14 canine sebaceous tumors were diagnosed as seven adenomas, four borderline tumors, and three epitheliomas. Histologically, the sebaceous adenomas showed nodules consisting of mature sebocytes surrounded by monolayer basaloid cells. In contrast, the portion of the reserve cells was increased, the portion of lipidized cells was decreased, and the majority of lipidized cells were found to be immature in sebaceous epithelioma. In the sebaceous adenomas, necrosis was not observed and mitotic figures were rarely seen. However, necrosis and mitotic figures were highly frequent in both borderline tumor and sebaceous epithelioma. Immunohistochemistry revealed that borderline tumor and sebaceous
epithelioma showed significantly higher expression against Ki-67 than sebaceous adenoma. We conclude that it is more accurate to employ the cut-off value of 50% reserve cells in humans rather than the current 90% reserve cells for classifying sebaceous gland tumors in dogs, thereby providing new insight into the characterization of the sebaceous gland tumors.