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 melanotic macule (brown spot on lip) (Stony Brook Case 1) dermatology dermatopathology PDF) Labial Melanotic Macule Diagnosed by Dermoscopy Melanotic macule. Benign. Dark spot on labia (or lip). Analogous to lentigo simplex. Hyperpigmented basal keratinocytes & dermal melanophages. Slight in single basal melanocytes; NO nests. More info like this in Melanotan II Indications, Uses, and Side Effects_Chemicalbook