University of Wisconsin School of Medicine and Public Health, 750 Highland Ave, Madison, WI, USA.
Diagn Pathol. 2013 Nov 25;8:192. doi: 10.1186/1746-1596-8-192.
Clear cell sarcoma is a rare cancer primarily of tendons, fascia, and aponeuroses that can be difficult to discern from primary cutaneous malignant melanoma. The two cancers share several histological markers, with most cases of both cancers staining positively for S-100, HMB-45, and melanin. Primary therapy of both cancers involves wide local excision, but while systemic therapy has proven benefit for malignant melanoma, it has not been established for clear cell sarcoma.We report the case of a 58 year old woman with a large, ulcerated, fungating mass on her left lower leg. Frozen section of the mass showed a malignant epithelioid and spindle cell tumor confined to the subcutaneous tissue. A provisional diagnosis of soft-tissue sarcoma was made. Through in-depth study of initial biopsy with immunohistochemistry for S-100, HMB-45, MART-1, and MITF, along with karyotyping and FISH analysis for EWS gene rearrangement, the diagnosis of amelanotic malignant melanoma was confirmed. The patient then underwent systemic treatment with ipilimumab upon recurrence with good response.
The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1989338475107348.
透明细胞肉瘤是一种罕见的癌症，主要发生于肌腱、筋膜和腱膜，很难与原发性皮肤恶性黑色素瘤区分。这两种癌症有几个组织学标志物，大多数透明细胞肉瘤和恶性黑色素瘤的病例均对 S-100、HMB-45 和黑色素呈阳性染色。两种癌症的主要治疗方法均为广泛局部切除，但恶性黑色素瘤的全身治疗已被证明有效，而透明细胞肉瘤的全身治疗尚未确定。我们报告了一例 58 岁女性，左小腿有一个大的溃疡性、隆起性肿块。肿块的冷冻切片显示恶性上皮样和梭形细胞肿瘤局限于皮下组织。初步诊断为软组织肉瘤。通过对初始活检进行深入研究，包括 S-100、HMB-45、MART-1 和 MITF 的免疫组织化学染色，以及 EWS 基因重排的核型分析和 FISH 分析，最终确诊为无黑色素恶性黑色素瘤。随后，患者在复发时接受了伊匹单抗的全身治疗，反应良好。
