硬骨鱼的甲状腺组织主要位于咽部区域，通常到达其他邻近的解剖位置。在此，通过手术切除了塞内加尔鲷（Diplodus bellottii）左鳃盖处的结节性病变，并送去进行显微镜评估。显微镜下，病变呈现不规则边界，由排列成管状乳头状图案的柱状上皮细胞组成，围绕着充满无细胞、嗜酸和均质物质（“胶体”）的中央管腔。为了确定病变的组织发生，使用 AE1/AE3、CK7、甲状腺球蛋白和波形蛋白抗体进行免疫组织化学分析。肿瘤细胞表现出低有丝分裂指数和 CK7 和甲状腺球蛋白免疫标记阳性。因此，诊断为异位甲状腺腺瘤。本文描述了经典用于哺乳动物的抗体的成功应用，以准确诊断甲状腺疾病。鱼类甲状腺组织的增殖可能反映了环境和生理失衡，因此对该物种中这些肿瘤的研究和正确诊断非常重要。© 2024 John Wiley

Thyroid tissue in teleosts is located mainly in the pharyngeal region, usually reaching other adjacent anatomical locations. Herein, a nodular lesion located in the left operculum of a Senegal seabream (Diplodus bellottii) was surgically excised and sent for microscopical evaluation. Microscopically, the lesion presented irregular borders and consisted in columnar epithelial cells arranged in a tubulopapillary pattern, surrounding a central lumen filled with acellular, acidophilic and homogeneous, material ('colloid'). To determine the lesion's histogenesis, immunohistochemistry was performed employing antibodies for AE1/AE3, CK7, thyroglobulin and vimentin. The neoplastic cells presented low mitotic index and positive immunolabelling for CK7 and thyroglobulin. Therefore, a diagnosis of ectopic thyroid adenoma was made. Herein, the successful employment of antibodies classically used in mammals for accurate diagnosis of thyroid disorders is described. Proliferation of thyroid tissue in fish may reflect environmental and physiological imbalances, making the study and correct diagnosis of these tumours in this species important.© 2024 John Wiley & Sons Ltd.