Barnhart K F, Edwards J F, Storts R W
Department of Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station 77833-4457, USA.
Vet Pathol. 2001 May;38(3):332-6. doi: 10.1354/vp.38-3-332.
A granular cell tumor involving the pituitary gland, optic chiasm and ventral pyriform lobes was discovered in a 12-year-old Labrador Retriever. Clinical signs included acute blindness, seizures, ataxia, weakness, and behavioral changes. The diagnosis was established by histopathologic and ultrastructural examination of neoplastic tissues collected at necropsy. Granular cell tumors involving the central nervous system are well documented in humans but rarely have been described in dogs. The location of the neoplasm and the clinical symptoms seen in this dog closely parallel those of a rare syndrome in humans commonly described as symptomatic parasellar or pituitary granular cell tumors. The cell of origin for these tumors is still highly debated, and attempts to characterize human granular cell tumors through immunohistochemistry have produced conflicting results. An immunohistochemical profile of this neoplasm revealed focal positive staining for vimentin with a lack of staining for neuron-specific enolase, glial fibrillary acidic protein, S-100, and synaptophysin. All neoplastic cells were strongly positive with the periodic acid-Schiff reaction.
在一只12岁的拉布拉多寻回犬中发现了一个累及垂体、视交叉和腹侧梨状叶的颗粒细胞瘤。临床症状包括急性失明、癫痫发作、共济失调、虚弱和行为改变。通过对尸检时收集的肿瘤组织进行组织病理学和超微结构检查确诊。累及中枢神经系统的颗粒细胞瘤在人类中有充分的文献记载，但在犬类中很少被描述。该犬肿瘤的位置和临床症状与人类一种罕见综合征（通常称为症状性鞍旁或垂体颗粒细胞瘤）的症状非常相似。这些肿瘤的起源细胞仍存在激烈争论，通过免疫组织化学对人类颗粒细胞瘤进行特征描述的尝试也产生了相互矛盾的结果。该肿瘤的免疫组织化学图谱显示波形蛋白呈局灶性阳性染色，而神经元特异性烯醇化酶、胶质纤维酸性蛋白、S-100和突触素均无染色。所有肿瘤细胞对过碘酸希夫反应均呈强阳性。
