However, a singular, hard bump on the tongue can be a cancerous growth. Sores, red or white spots, irritated spots, numbness, lumps, and growths in the mouth are common signs of cancer.

White spots on the tongue may be callous-like spots that come ... inflammatory condition of the tongue that results in white and red patches which may have slightly raised borders that quickly ...

Red spots then appear on the tongue and inside of the mouth a couple of days later. The spots can turn into painful ulcers ...