Kim Young Jee, Lee Jee-Bum, Kim Seong-Jin, Lee Seung-Chul, Won Young Ho, Yun Sook Jung
Department of Dermatology, Chonnam National University Medical School, Gwangju, Korea.
Ann Dermatol. 2015 Apr;27(2):201-5. doi: 10.5021/ad.2015.27.2.201. Epub 2015 Mar 24.
Amelanotic acral melanoma is rare and difficult to diagnose, both clinically and pathologically. KIT mutations are frequently found in acral melanomas and are considered a risk factor for poor prognosis. The presence of vitiligo in melanoma has been reported, and KIT is thought to be partly responsible for the dysfunction and loss of melanocytes observed in vitiligo. We report a case of amelanotic subungual melanoma with multiple metastases that was associated with KIT mutation and vitiligo. An 85-year-old man presented with a 3-year history of a tender erythematous ulcerated tumor on the left third fingertip and developed hypopigmented patches on the face and trunk. Histopathological examination of the ulcerative tumor showed aggregates of tumor cells that were pleomorphic epithelioid cells. Immunohistochemical staining of the tumor cells was positive for S100, HMB45, and c-Kit. Histopathological findings from the hypopigmented patch on the face were consistent with vitiligo. Mutation analysis showed a KIT mutation in exon 17 (Y823D). The patient had metastasis to the brain, liver, bone, and both lungs. The patient refused chemotherapy, and died 3 months after the first visit.
无色素性肢端黑色素瘤罕见，在临床和病理上均难以诊断。KIT突变在肢端黑色素瘤中经常被发现，被认为是预后不良的一个危险因素。黑色素瘤中白癜风的存在已有报道，并且KIT被认为部分导致了白癜风中观察到的黑素细胞功能障碍和缺失。我们报告一例伴有多发转移的无色素性甲下黑色素瘤病例，该病例与KIT突变和白癜风相关。一名85岁男性，左手中指指尖出现一个压痛性红斑溃疡性肿瘤，病史3年，面部和躯干出现色素减退斑。对溃疡性肿瘤进行组织病理学检查显示肿瘤细胞聚集，为多形性上皮样细胞。肿瘤细胞的免疫组化染色S100、HMB45和c-Kit呈阳性。面部色素减退斑的组织病理学表现与白癜风一致。突变分析显示第17外显子（Y823D）存在KIT突变。该患者发生了脑、肝、骨和双肺转移。患者拒绝化疗，首次就诊3个月后死亡。
