Best Lip Pigmentation Treatment 2026 Frontiers Case report: A rare case of massive peripheral nerve melanotic schwannoma and review of the literature An oral melanotic macule is a harmless dark spot found on the lip, most often the lower lip, or inside the mouth, either on the gums, inside the cheek, or on the roof of the mouth. An oral melanotic Skin Lesions in Melanoma and Kaposi's Sarcoma Journal of Clinical Oncology