Ho K K, Dervan P, O'Loughlin S, Powell F C
Regional Centre of Dermatology, Mater Misercordiae Hospital, Dublin, Ireland.
J Am Acad Dermatol. 1993 Jan;28(1):33-9. doi: 10.1016/0190-9622(93)70005-e.
The labial melanotic macule (LMM) is a recently described pigmentary anomaly that may simulate malignant melanoma.
Our purpose was to define the LMM clinically, histologically, and immunohistochemically in a large group of patients.
We describe the clinical features of 36 LMMs in 29 patients (aged from 4 to 79 years, 4 male, 25 female) seen during the past 4 years. Histopathologic findings in 21 of these patients are discussed. Seventeen lesions were immunostained with HMB-45 monoclonal antibody, and electron microscopy was performed on eight lesions.
The majority of patients were women and had solitary lesions on the lower lip with the mean age of onset of 30 years. Histologically prominent basilar hyperpigmentation accentuated at the tips of the rete ridges was present without atypia or nevoid formation. Immunohistochemical studies showed that all intralesional melanocytes were HMB-45 negative, supporting their benign nature. Ultrastructurally, numerous stage III and IV melanosomes clustered within basal keratinocytes and papillary dermal melanophages were found.
The LMM is a clinically and histologically distinctive benign pigmentary anomaly.
唇部黑素沉着斑（LMM）是一种最近被描述的色素异常，可能类似恶性黑色素瘤。
我们的目的是在一大组患者中从临床、组织学和免疫组织化学方面对唇部黑素沉着斑进行定义。
我们描述了在过去4年中见到的29例患者（年龄4至79岁，男性4例，女性25例）的36个唇部黑素沉着斑的临床特征。讨论了其中21例患者的组织病理学发现。17个损害用HMB - 45单克隆抗体进行免疫染色，8个损害进行了电子显微镜检查。
大多数患者为女性，下唇有孤立损害，平均发病年龄为30岁。组织学上可见显著的基底色素沉着，在 rete 嵴尖端加重，无异型性或痣样形成。免疫组织化学研究表明，所有损害内的黑素细胞HMB - 45均为阴性，支持其良性性质。超微结构上，发现大量III期和IV期黑素小体聚集在基底角质形成细胞内，真皮乳头层有黑素巨噬细胞。
唇部黑素沉着斑是一种临床和组织学上独特的良性色素异常。
