Pigmented Oral Lesions: Clues to Identifying the Potentially Malignant Consultant360 COM March 2009 Diagnosis UW School of Dentistry A Case Report of Oral Malignant Melanoma: A Silent Killer Cureus 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. Oral Melanotic Macule: Symptoms and Treatment Skinsight