Lesional Markers and Precursors of Melanoma Dermatologic Clinics Brown spots, especially on the lips, can be alarming to some. In some instances it can indicate rare oral mucosal melanoma, however in this case it was a non cancerous labial melanotic macule. Labial melanotic macule Pigmented skin lesions The BMJ Differential Diagnosis of Pigmented Lesions in the Oral Mucosa: A Clinical Based Overview and Narrative Review Pigmented Lesions of the Oral Mucosa Pocket Dentistry