So far I've only had squamous and basal cell tumors. No melanoma... knock wood. Still, the first time the doctor says to you "you have a cancer" it comes as a shock and a wake up call.
Do look into sun-blocking shirts and pants. Wide brimmed hats. Good quality sun screen.
Do not give up on sailing so easily!
(Although, if you still want to give away your boat, I'm currently "between boats" and looking!)