Requena L, Sangueza O P, Sánchez Yus E, Furio V
Department of Dermatology, Fundación Jiménez Díaz, Universidad Autónoma, Madrid, Spain.
J Cutan Pathol. 1997 Mar;24(3):176-82. doi: 10.1111/j.1600-0560.1997.tb01573.x.
Atypical fibroxanthoma is a superficial variant of pleomorphic malignant fibrous histiocytoma. Histopathologically, it is characterized by a dermal nodule composed of bizarre cells arranged in a haphazard-to-fascicular pattern. These cells are spindle or rounded, pleomorphic and with numerous atypical mitotic figures. Some cells appear polygonal with ample and foamy cytoplasm. We recently encountered two elderly patients with atypical fibroxanthoma on their face. Histopathologically, one of the lesions was composed, almost entirely, of clear cells, whereas in the other one aggregations of clear cells constituted a half of the neoplasm. Atypical multinucleated cells with a Touton-like appearance were present. In addition to clear cells, areas of more conventional atypical spindle cells arranged in fascicles were seen, supporting the diagnosis of atypical fibroxanthoma. PAS staining failed to demonstrate glycogen in neoplastic cells. Immunohistochemistry revealed that neoplastic cells expressed positivity for vimentin, muscle-specific actin, and alpha smooth muscle actin, whereas cytokeratin, S-100 protein, EMA, CEA, and desmin were negative. Ultrastructural studies showed that neoplastic cells contained abundant rough endoplasmic reticulum, mitochondria, and numerous lipid vacuoles within the cytoplasm. Clear-cell atypical fibroxanthoma is a rare variant of atypical fibroxanthoma that should be differentiated from other clear-cell neoplasms of the skin.
非典型纤维黄色瘤是多形性恶性纤维组织细胞瘤的一种浅表型。组织病理学上，其特征为真皮结节，由排列杂乱至束状的奇异细胞组成。这些细胞呈梭形或圆形，多形性，有许多非典型有丝分裂象。一些细胞呈多边形，胞质丰富且呈泡沫状。我们最近遇到两名老年患者面部患有非典型纤维黄色瘤。组织病理学上，其中一个病变几乎完全由透明细胞组成，而另一个病变中透明细胞团占肿瘤的一半。存在具有图顿样外观的非典型多核细胞。除了透明细胞外，还可见到呈束状排列的更典型的非典型梭形细胞区域，支持非典型纤维黄色瘤的诊断。PAS染色未能在肿瘤细胞中显示糖原。免疫组织化学显示肿瘤细胞对波形蛋白、肌肉特异性肌动蛋白和α平滑肌肌动蛋白呈阳性表达，而细胞角蛋白、S-100蛋白、EMA、CEA和结蛋白呈阴性。超微结构研究表明，肿瘤细胞胞质内含有丰富的粗面内质网、线粒体和许多脂质空泡。透明细胞型非典型纤维黄色瘤是一种罕见的非典型纤维黄色瘤变体，应与皮肤的其他透明细胞肿瘤相鉴别。
