Shimoda H, Oka K, Naoi Y, Nishida S, Oka T, Nakazato Y, Mori N
Department of Orthopedics, Mito Saiseikai General Hospital, Ibaraki, Japan.
Clin Neuropathol. 1999 Mar-Apr;18(2):80-3.
Primary melanocytoma arising from the leptomeninges of the spinal cord is very rare. A surgical specimen of a thoracic meningeal tumor was resected from a 75-year-old woman complaining of gait disturbance was investigated. Magnetic resonance imaging and myelography showed a dumb-bell-type tumor in the subdural space at the 1st to 2nd thoracic vertebrae. The tumor was subtotally resected because of adhesion to the lamina and thoracic medulla. The localized, gelatinous black tumor showed a well-defined margin without dissemination or infiltration. The tumor had a thin capsule and was composed of solid proliferation of neoplastic melanocytes. Neither whorl formation nor foci of palisaded nuclei were observed. The neoplastic cells were of two major types: an epithelioid- or polygonal-shaped type and a spindle-shaped type, and had a large nucleus, a prominent nucleolus, coarse chromatin, and melanin-pigments in their cytoplasm. Only a few mitotic figures were observed. They were positive for HMB-45 and S-100 protein. This case was considered to be primary melanocytoma arising from the thoracic leptomeninges.
起源于脊髓软膜的原发性黑素细胞瘤非常罕见。对一名75岁主诉步态障碍的女性患者切除的胸段脑膜肿瘤手术标本进行了研究。磁共振成像和脊髓造影显示第1至2胸椎水平硬膜下间隙有一个哑铃型肿瘤。由于肿瘤与椎板和胸段脊髓髓质粘连，进行了次全切除。局部的、凝胶状黑色肿瘤边界清晰，无播散或浸润。肿瘤有一层薄包膜，由肿瘤性黑素细胞的实性增生构成。未观察到漩涡状结构或栅栏状核灶。肿瘤细胞主要有两种类型：上皮样或多边形细胞类型和梭形细胞类型，细胞核大，核仁突出，染色质粗糙，胞质内有黑色素。仅观察到少数有丝分裂象。它们对HMB-45和S-100蛋白呈阳性。该病例被认为是起源于胸段软膜的原发性黑素细胞瘤。
