Tsugu Hitoshi, Nabeshima Kazuki, Matsumoto Shinji, Omura Tadahiro, Yahiro Tatsumi, Oshiro Shinya, Komatsu Fuminari, Abe Hiroshi, Fukushima Takeo, Inoue Toru, Takano Koichi
Department of Neurosurgery, Fukuoka University Faculty of Medicine, 45-1-7 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan.
Brain Tumor Pathol. 2009;26(1):25-9. doi: 10.1007/s10014-008-0242-8. Epub 2009 Apr 30.
We present an extremely rare case of an orbital melanocytoma that occurred in a 51-year-old man. The patient suffered from diplopia and mild exophthalmos of the right eye for 2 months. Brain magnetic resonance imaging showed a well-demarcated round mass 3.5 cm in diameter in the right orbit. We performed total resection of this tumor. Histological findings revealed a proliferation of large polygonal cells with fine pigment granules in the cytoplasm and prominent nucleoli. Although these tumor cells revealed immunohistochemical reactivity in HMB-1, there was no S-100 or Melan A antibody reactivity. Also, there were no malignant findings of nuclear polymorphism, mitoses, or necrosis. The brown pigments were confirmed to be melanin by bleaching and the Fontana-Masson silver stain method. The MIB-1 labeling index was less than 1%. This tumor also consisted of 50% melanophages, which revealed immunohistochemical reactivity in CD68, CD163, and in (1-AT antibodies. These histological findings led us to diagnose an orbital melanocytoma with partial tumor regression.
我们报告一例极为罕见的眼眶黑素细胞瘤，发生于一名51岁男性。患者右眼复视和轻度眼球突出2个月。脑部磁共振成像显示右眼眶内有一个边界清晰的圆形肿块，直径3.5厘米。我们对该肿瘤进行了全切除。组织学检查结果显示，大的多边形细胞增生，细胞质内有细小色素颗粒，核仁明显。尽管这些肿瘤细胞在HMB-1中显示免疫组化反应性，但无S-100或Melan A抗体反应性。此外，也没有核多形性、有丝分裂或坏死的恶性表现。通过漂白和Fontana-Masson银染法证实棕色色素为黑色素。MIB-1标记指数小于1%。该肿瘤还由50%的噬黑素细胞组成，这些细胞在CD68、CD163和α1-抗胰蛋白酶抗体中显示免疫组化反应性。这些组织学检查结果使我们诊断为眼眶黑素细胞瘤伴部分肿瘤消退。
