右侧第三颅神经原发神经内神经束膜瘤1例及文献复习

Intraneural Perineurioma of Right Third Cranial Nerve:One Case Report and Literature Review

目的报道1例罕见的右侧第三颅神经发生的神经束膜瘤,探讨其组织病理学特点和鉴别诊断,提高对该病的认识。方法右侧第三颅神经发生的肿瘤行部分切除,一部分瘤组织用多聚甲醛固定用作常规苏木精-伊红染色和免疫组织化学染色;另一部分用戊二醛固定用作电子显微镜观察。结果瘤细胞排列成典型的"洋葱头"样构象,免疫组织化学染色显示上皮膜抗原(EMA)和CD34阳性;电镜观察显示瘤细胞具有细长的胞质突起并呈现同心圆状的排列。结论神经束膜瘤是一种罕见的良性肿瘤,常发生于外周神经;颅神经原发的神经束膜瘤极为罕见。该例是已知报道中第2例发生于第三颅神经的病例。该肿瘤应当和中枢神经系统发生的神经鞘瘤、神经纤维瘤、孤立性纤维性肿瘤(SFT)、低分化纤维黏液肉瘤(LGFS)和脑膜瘤进行鉴别。

Objective Intraneural perineurioma is a rare neoplasm which originates from perineural cells and mainly affects peripheral nerves.We described one case of intraneural perineurioma of right third cranial nerve with mixed collagenous-myxoid stroma and diffuse CD34 immunopositivity in a 47-year-old Chinese female patient.Methods The neoplasm was localized in the right third cranial nerve and was partially excised.One part of the specimen was fixed in formalin and embedded in paraffin,and the rest part was fixed in formaldehyde and glutaraldehyde.The histological and immunohistocemical features of the neoplasm were assessed,and the ultrastructure of the tumor cells was studied under the electron microscopy.Results The tumor cells arranged in characteristic pseudo-onion bulb formation and showed immunopositivity of epithelial membrane antigen（EMA）and CD34.The ultrastructure showed concentric arrangements of perineurial cells with long,thin cytoplasmic processes.ConclusionIntraneural perineurioma primarily affects peripheral nerves of the extremities.To our knowledge,this is the second case of intraneural perineurioma of right third cranial nerve.The tumor should be distinguished from mimic lesions including schwannoma,neurofibroma,and solitary fibrous tumor,low grade fibrous myxoid sarcoma（LGFS）and meningioma.