无色素性黑素瘤误诊为表皮囊肿1例

患者男,39岁。头部红色结节、斑块2年。2年前患者头部出现一黄豆大红色结节,当地医院以"表皮囊肿"相继予激光和手术治疗,皮损均复发。皮损组织病理示:表皮与真皮交界处和真皮内瘤细胞呈巢状分布,肿瘤细胞大小不等,核深染,具显著异型性,肿瘤细胞内无明显黑素颗粒。免疫组化检查:瘤细胞表达S-100及Melan-A。CT检查示肺转移癌。诊断:无色素性黑素瘤。

A Case of Amelanotic Malignant Melanoma Misdiagnosed as Epidermal Cyst

A 39-year-old male presented with some red nodules and plaques on his scalp two years before,which was diagnosed as "Epidemal cyst" and treated by laser treatment and local excision without biopsy in the local hospital but relapsed quickly.Histopathological examnation of the skin lesion revealed the tumor cells arranged as nest in dermoepidermal junction and dermis,with various shapes,nucleolus hyperchromatism and obvious heteromorphism.No obvious melanin was observed in the tumor cells.Immunohistochemistry staining for S-100 and melan-A were positive in the tumor cells.The CT result showed metastasic lung cancer.Amelanotic malignant melanoma was diagnosed based on clinical and histopathologyical features.