Melanotic sarcoma growing from the mucous membrane of the lip and upper alveolar border of the jaw SuperStock View of Malignant melanotic nerve sheath tumor with PRKAR1A, KMT2C and GNAQ mutations Free Neuropathology 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 Pigmented Lesions of the Oral Cavity Oral and Maxillofacial Surgery Clinics Melanoma Treatment & Pharmacologic Management