Extension Without Malignant Changes in Oral Melanotic Macule: A Report of Two Cases and Review of the Literature Melaninassociated pigmented lesions of the oral mucosa: presentation, differential diagnosis, and treatment Mller 2010 Dermatologic Therapy Wiley Online Library 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. Smoker's melanosis Wikipedia