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 Lentigo (labial melanotic macule) Cancer Therapy Advisor Definition of melanocytic macules associated with Peutz Jeghers syndrome NCI Dictionary of Genetics Terms NCI Pigmented Lesions of the Oral Mucosa Pocket Dentistry