Labial Lentigo (labial melanotic macule) Cancer Therapy Advisor What to do with pigmented oral lesions? Mucosal melanocytic macules Oral Malignant Melanoma Oral Cancer Foundation Information and Resources about Oral Head and Neck Cancer Oral melanoacanthoma and oral melanotic macule: a report of 8 cases, review of the literature, and immunohistochemical analysis ORAL MELANOTIC MACULE (OMM) (Also called focal melanosis labial melanotic macule) A benign, localized, flat pigmented lesion of the oral mucosa Caused by a focal increase in melanin production