A new mole or spot appears on your skin
An existing mole changes in size, shape, or color
A spot has uneven borders
A spot has multiple colors or unusual darkening
A spot is larger than a pencil eraser
A mole or spot looks different from your other moles
A sore does not heal after several weeks
A spot bleeds, crusts, or scabs repeatedly
A spot itches, hurts, or becomes tender
A red, rough, scaly patch appears and persists
A shiny, pearly, or waxy bump appears
A firm, red nodule appears and grows
A dark streak appears under a fingernail or toenail
A mole becomes raised or changes texture
A spot spreads beyond its original border
You notice rapid growth of a skin lesion
You have a family history of skin cancer
You have frequent sunburns or heavy sun exposure
You notice any skin change that is new, changing, or unusual