Oral cancer often presents with a sore in the mouth that does not heal or persistent pain in the mouth. Other common symptoms include a persistent lump or thickening in the cheek, or a persistent white or red patch on the gums, tongue, tonsil, or lining of the mouth. Signs of oral cancer include bleeding, skin ulceration, facial swelling, a neck mass, trismus, facial numbness, and paralysis of the facial musculature.