Can melanoma pop up suddenly?

Yes: Any change whether it be size or color or texture of a pigmented skin lesion is suspect for melanoma. You should get anything that changes checked even if it is something that changed suddenly.

Yes: Many times my patients will notice a dark skin lesion for the first time that is melanoma.

Yes: Melanomas can pop up anywhere on your skin, or sometimes in weird places like the mucous membranes or back of the eye. As they arise from melanocytes, over a third of the time they will arise inside a pre-existing mole or dysplastic mole...either suddenly, or after smouldering for a few months or years. That is why surveillance of moles for any changes is important.