McKinnon Elizabeth L, West Kelly L, Ball Russell A, Wright Nathan, Barnhill Raymond L
*Duke University Medical Center, Durham, NC; †Ball Dermpath, Greensboro, NC; ‡Wilson Dermatology Clinic PA, Wilson, NC; and §Department of Pathology, Institut Curie, Faculty of Medicine, University of Paris Descartes, Paris, France.
Am J Dermatopathol. 2017 Sep;39(9):e147-e150. doi: 10.1097/DAD.0000000000000968.
Folliculotropic metastasis of cutaneous melanoma is rare, with only 5 published case reports in the English language literature since it was first described in 2009. We report a 41-year-old man with a primary cutaneous melanoma of the right upper preauricular region with metastatic spread to the parotid gland and pulmonary lymph nodes. Excision of the primary lesion was performed and immunotherapy was initiated. Sixteen months later, the patient presented with 2 new lesions of the left forehead and left neck. Histopathological examination was consistent with folliculotropic dermal deposits of metastatic melanoma. Deeper sectioning into the blocks revealed only sparse perifollicular pigment deposition and rare dermal melanocytes-a potential diagnostic pitfall had this been seen in the initial sections. This case represents the sixth and youngest patient to date with folliculotropic metastatic melanoma. This entity often presents in patients with advanced disease, including increased Breslow thickness and/or multiple metastases to lymph nodes, internal organs, or both. The folliculotropic metastases tend to be small and are often multiple. The precise relationship between folliculotropic primary melanoma and folliculotropic metastasis is unclear. In one reported case and in our patient, the primary tumor was noted to have a "folliculocentric" pattern. Because of the latter finding, the differential diagnosis includes multiple primary folliculotropic melanomas. Thus, clinical correlation and knowledge concerning the evolution of disease in the patient are critical. This case highlights a rare and unusual pattern of metastatic melanoma and potential problems in differential diagnosis.
皮肤黑色素瘤的毛囊性转移较为罕见，自2009年首次被描述以来，英文文献中仅有5篇已发表的病例报告。我们报告了一名41岁男性，其右耳前上部区域原发性皮肤黑色素瘤已转移至腮腺和肺门淋巴结。对原发性病变进行了切除，并开始免疫治疗。16个月后，患者左前额和左颈部出现2个新病灶。组织病理学检查结果与转移性黑色素瘤的毛囊性真皮沉积一致。对组织块进行更深层次切片后发现，仅见稀疏的毛囊周围色素沉着和罕见的真皮黑素细胞——若在最初切片中看到这种情况，可能会造成诊断陷阱。该病例是迄今为止第六例也是最年轻的毛囊性转移性黑色素瘤患者。这种情况常出现在疾病晚期患者中，包括Breslow厚度增加和/或淋巴结、内脏或两者均发生多处转移。毛囊性转移灶往往较小且常为多发。毛囊性原发性黑色素瘤与毛囊性转移之间的确切关系尚不清楚。在一篇报道的病例以及我们的患者中，原发性肿瘤均呈现“以毛囊为中心”的模式。鉴于后一发现，鉴别诊断包括多个原发性毛囊性黑色素瘤。因此，临床相关性以及对患者疾病演变的了解至关重要。本病例突出显示了转移性黑色素瘤一种罕见且不寻常的模式以及鉴别诊断中潜在的问题。
