Oral pigmented lesions: a pragmatic approach to diagnosis and management Faculty Dental Journal COM Dec. 2011 Diagnosis UW School of Dentistry Melanotic Macules, Naevi, and Melanoma Springer Nature Link 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.