Kindblom L G, Meis-Kindblom J M, Havel G, Busch C
Department of Pathology, Gothenburg Musculoskeletal Tumor Center, Sahlgrenska University Hospital, University of Gothenburg, Sweden.
Am J Surg Pathol. 1998 Jun;22(6):762-70. doi: 10.1097/00000478-199806000-00015.
Benign schwannoma (neurilemoma) has various morphologic patterns that may cause problems in differential diagnosis. Although an epithelioid variant of malignant schwannoma simulating carcinoma and melanoma is well recognized, a benign counterpart has not yet been defined. In the current study, we describe five cases of benign epithelioid schwannoma that were in the subcutis (four cases) and the neck of the urinary bladder (one case). The tumors occurred in adults 28-73 years of age, were 1-4.5 cm in diameter, were well circumscribed and cellular, and were composed of epithelioid cells arranged in cords and nests. The benign nature of the lesions was evident by a constellation of features, including small size, sharp circumscription, bland morphology, low proliferative activity (four of five had < or =1% Ki67 immunostaining), and a benign clinical course after either marginal or intralesional excision. All cases had some features of classic schwannoma light microscopically and a high degree of Schwann cell differentiation both ultrastructurally and immunohistochemically. The recognition of benign epithelioid schwannoma is important because it may be misinterpreted as a malignant neuroectodermal, mesenchymal, epithelioid, or melanocytic tumor.
良性神经鞘瘤（神经膜瘤）具有多种形态学模式，这可能在鉴别诊断中引发问题。尽管模拟癌和黑色素瘤的恶性神经鞘瘤的上皮样变体已广为人知，但尚未定义其良性对应物。在本研究中，我们描述了5例良性上皮样神经鞘瘤，其中4例位于皮下，1例位于膀胱颈部。肿瘤发生于28至73岁的成年人，直径为1至4.5厘米，边界清楚且细胞丰富，由排列成条索状和巢状的上皮样细胞组成。病变的良性性质通过一系列特征得以体现，包括体积小、边界清晰、形态温和、增殖活性低（5例中有4例Ki67免疫染色≤1%）以及在边缘切除或瘤内切除后呈良性临床病程。所有病例在光镜下均具有一些经典神经鞘瘤的特征，并且在超微结构和免疫组织化学方面均表现出高度的施万细胞分化。认识良性上皮样神经鞘瘤很重要，因为它可能被误诊为恶性神经外胚层、间叶、上皮样或黑素细胞肿瘤。
