Most likely your personal insurance will not cover you outside of the U.S. Better check this out before you decide to sail without it.
A recent poster told her story of breaking an ankle while walking around a port. She went to a local hospital for treatment and in the meantime the ship sailed without her. Her family of 4 had to find their own way back to the U.S. The insurance company had to send a representative to the next port to remove her and her family's belongings from the ship, which they charged her for. Her bill was $12,000 and her trip insurance covered it all.
Do you want to risk it?