微囊性/网状神经鞘瘤的临床病理特点

目的 探讨微囊性/网状神经鞘瘤的形态学和免疫表型特点及鉴别诊断.方法 收集1例发生在颈椎的微囊性/网状神经鞘瘤,根据HE切片和免疫组织化学染色观察形态学及免疫表型特点,并复习相关文献.免疫组织化学采用EnVision两步法.结果 患者男,35岁,因颈部不适就诊,影像学检查见颈5椎体破坏,肿块周围有硬化带,考虑良性病变.手术中见椎体破坏,肿瘤无包膜,结节状,质软,大小约3.5 cm×3.0 cm×1.8 cm.镜下观察,肿瘤无明确包膜,结节状分布,细胞学明确呈两种形态,一种类似于普通神经鞘瘤,但局灶细胞显示明显多形性,似神经鞘瘤伴退变,另一区域呈上皮样细胞,呈网状或蕾丝花边样排列,间质伴显著黏液变性.免疫组织化学示两种区域细胞表达一致,强阳性表达波形蛋白、S-100蛋白、胶质纤维酸性蛋白和神经元特异性烯纯化酶,散在表达CD68、CD10和Ki-67,不表达细胞角蛋白、上皮细胞膜抗原、神经微丝、癌胚抗原、平滑肌肌动蛋白、雌孕激素受体和p53.结论 微囊性/网状神经鞘瘤是神经鞘瘤的一种特殊形态学变型,临床罕见,发生在骨内更为罕见,熟悉其组织学特点和免疫表型有助于与脊索瘤和其他黏液性肿瘤或肉瘤鉴别.

Microcystic/reticular schwannoma occurring in cervical spine: report of a case with literature review

Objective To study the morphologic characteristics, immunophenotype and differential diagnosis of a case of microcystic/reticular schwannoma occurring in cervical spine. Methods The pathologic features and immunophenotypic profile of a case of microcystic/reticular schwannoma were studied. Immunohistochemistry was performed using EnVision two-step method. Results The patient was a 35 -year-old male and presented with a bump over the fifth cervical spine on radiologic check up. Crossly,the bump was gray-white in color, soft, well-circumscribed but non-encapsulated. The tumor measured 3.5 cm ×3.0 cm × 1. 8 cm in size. Histologically, it was composed of two distinctive components. One component resembled the conventional schwannoma but showed focally nuclear pleomorphism, reminiscent of changes in degenerating schwannoma. The other component consisted of epithelial-like cells arranged in a reticular or lacelike pattern, amongst a myxoid matrix. Immunohistochemical study showed that the tumor cells were strongly positive for vimentin, S-100 protein, glial fibrillary acidic protein and neuron-specific enolase, focally positive for CD68, CD10 and Ki-67, and negative for pan-cytokeratin, epithelial membrane antigen, neurofilament, carcinoembryonic antigen, smooth muscle actin, estrogen receptor, progesterone receptor and p53. Conclusions Microcystic/reticular schwannoma is a novel variant of schwannoma,arising mainly in internal viscera but seldom in bone. Awareness of this entity is helpful in distinction from chordoma, other mucoid tumors or sarcomas.