Skin Cancer Lentigo Maligna Melanoma
Lentigo maligna and lentigo maligna melanoma account for about 5-10% of all melanomas. Lentigo maligna represents in situ or intraepidermal melanoma. Progression to invasive lentigo maligna melanoma occurs in 5% of patients. They are equally common in males and females, usually in older people. They develop over years or decades on sun-exposed Caucasian skin, most often affecting the face, neck or dorsal arms. LMM may have a complex patten. Years of migration and regression can produce lesions with a shape more varied and bizarre than that of SSM. The color is more uniform than SSM, but red and white may occur later. Lesions tend to be flat and irregularly outlined. Lesions tend to look mottled or washed out and often contain areas of normal pigmentation. Woods light often reveals irregular pigmentation extending well beyond the clinical lesion. Nodules and ulceration may indicate local invasion.