Brick Katherine E, Halling Kevin C, Khan Yulia K, Peters Margot S
Department of Dermatology, Mayo Clinic, Rochester, MN 55905, USA.
Am J Dermatopathol. 2013 Jul;35(5):609-12. doi: 10.1097/DAD.0b013e31827a0bfb.
Primary cutaneous folliculotropic melanoma has been described rarely, and there are even fewer published cases of folliculotropic metastases. We report a 54-year-old man with history of primary cutaneous melanoma of the right posterior shoulder, Breslow depth of 3.4 mm, with one positive sentinel lymph node, negative full axillary dissection, and no extranodal metastases at initial staging. Three years later, he presented with an asymptomatic isolated 2-mm blue-black papule on the scalp and was found to have widespread metastatic melanoma involving lymph nodes, liver, adrenal glands, subcutaneous tissue, skeleton, and lung. Histopathologic examination of the scalp lesion demonstrated a tumor nodule composed of sheets and nests of large round to polygonal cells centered about a hair follicle and within follicular epithelium. BRAF V600E gene mutation was documented in this lesion, and the patient received vemurafenib, with dramatic improvement noted on positron emission tomography scan after 2 months of treatment, soon followed by development of extensive metastases, including to brain. Although BRAF mutations have been found in primary and metastatic melanomas of the skin, and in melanoma metastases of extracutaneous sites, to our knowledge, this is the first case of a BRAF mutation documented in folliculotropic metastatic melanoma.
原发性皮肤毛囊性黑色素瘤鲜有报道，毛囊性转移的病例更是少见。我们报告了一名54岁男性，有右后肩部原发性皮肤黑色素瘤病史，Breslow厚度为3.4mm，前哨淋巴结1枚阳性，腋窝清扫阴性，初始分期无结外转移。三年后，他头皮上出现一个无症状的孤立2mm蓝黑色丘疹，发现有广泛转移性黑色素瘤，累及淋巴结、肝脏、肾上腺、皮下组织、骨骼和肺。头皮病变的组织病理学检查显示一个肿瘤结节，由围绕毛囊及在毛囊上皮内的大片和巢状大圆形至多边形细胞组成。该病变检测到BRAF V600E基因突变，患者接受维莫非尼治疗，治疗2个月后正电子发射断层扫描显示显著改善，但随后很快出现广泛转移，包括脑转移。虽然在皮肤原发性和转移性黑色素瘤以及皮肤外部位的黑色素瘤转移中都发现了BRAF突变，但据我们所知，这是第一例在毛囊性转移性黑色素瘤中记录到BRAF突变的病例。
