If my dad had a skin cancer spot removed...?

If he will let you, consider going with him to the visit so you can ask questions about the cancer and risk of future cancer to both you and him. Melanoma has the most potential of the common skin cancers, but it is related to thickness of the cancer. So early (lowest level) has a very good chance of being gone. His risk of another one only ever goes up with time and age, as does yours and mine. That's why the check ups are so important as is protecting from the biggest risk factor, UVA light exposure. Find out what Clark level and Breslow thickness and then educate yourself about that level of melanoma since the prognosis is very different for the different thicknesses.