Mucosal melanocytic macules COM Jan. 2008 Diagnosis UW School of Dentistry Melanotic Macules, Naevi, and Melanoma Springer Nature Link Pigmented Lesions of the Oral Cavity Oral and Maxillofacial Surgery 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.