Abstract：
Divergent differentiation, mainly towards various subsets of mesenchymal cells, is encountered sporadically in human malignant peripheral nerve sheath tumours (MPNSTs) but this is the first report of epithelioid components within this neoplasm in a cat. An 8-year-old, spayed female Domestic Shorthaired cat was presented for surgical removal of a subcutaneous mass on the right flank. Morphological and immunohistochemical analysis revealed a malignant neoplasm with spindloid cells intermixed with an epithelioid component that had squamous differentiation. There was intense immunolabelling of vimentin, S100 protein, neuron-specific enolase, laminin and glial fibrillary acidic protein in the spindloid cell component and for cytokeratin (CK) AE1/AE3 and CK5/6 in the epithelial elements. Melanoma-associated antigen, desmin, α-smooth muscle actin, CD18, CD31, ionized calcium binding adapter molecule-1 and CK8/18 were not expressed, which helped differentiate the tumour from other feline spindloid cell neoplasms. These features are characteristic of divergent epithelioid differentiation of MPNST.
摘要：
不同的分化，主要针对间充质细胞的各种亚群，在人类恶性周围神经鞘瘤（MPNSTs）中偶尔遇到，但这是猫中这种肿瘤中上皮样成分的首次报道。一个8岁的孩子,接受家养的雌性短肢猫手术切除右侧腹部的皮下肿块。形态学和免疫组织化学分析显示，一种恶性肿瘤，其中纺状细胞与上皮样成分混合，并具有鳞状分化。波形蛋白有强烈的免疫标记，S100蛋白,神经元特异性烯醇化酶，轴突样细胞成分中的层粘连蛋白和神经胶质原纤维酸性蛋白，以及上皮元件中的细胞角蛋白（CK）AE1/AE3和CK5/6。黑色素瘤相关抗原,desmin,α-平滑肌肌动蛋白，CD18、CD31、离子钙结合接头分子-1和CK8/18不表达，这有助于将肿瘤与其他猫科动物的脊髓样细胞肿瘤区分开来。这些特征是MPNST的发散性上皮样分化的特征。
