Oral melanotic macule 2019-03-08T11:02:36Z Melanotic macules very rarely, if ever, present larger than one centimeter in diameter. Although these are innocuous lesions, a biopsy is usually warranted for diagnosis since mucosal melanoma can mimic the appearance of a melanotic macule. Melanotic macules are caused by functional hyperactivity of the regional melanocytes ie there is increased melanin production. Histologically, this is evidenced by abundant melanin pigmentation within the basal epithelial cell layer with melanin incontinence in the superficial portions of the submucosa. Importantly, there is no increase in melanocyte number. If there is evidence of melanocytic hyperplasia, it should be diagnosed as such and the lesion would likely warrant complete surgical removal. It is possible that melanocytic hyperplasia may potentially herald the development of malignant melanoma. Flat, distinct, discolored area of oral mucosal membrane less than 1 cm wide not associated with a change in the thickness or texture of the affected mucosal membrane. The lesions are small, solitary, well-circumscribed and often uniformly pigmented. Melanotic macule of oral mucosa Abnormal pigmentation of the oral mucosa