Anonalon, I've been thinking about you and your son through out the day, and continually praying. I don't know all the answers to what you should do right now, but I know God is sovereign and will lead you. One day we will understand all the ins and outs and whys of all these hard times. My little girl has a friend at school that is having some scary irregular moles too, she's six. I'm praying for them too.
I really do long for heaven when all the pain and suffering will be over, and there is not all this fear to struggle against all the time.