We all naturally shrink from pain and death, and we all want to preserve our lives–because God made us that way. If we weren't built like that, the human race would become extinct–and God's plan for us would be blocked. Remember: The Bible calls death "The last enemy" (1 Corinthians 15:26).
At the same time, pain, illness and death are also realities. But listen: God has conquered them! In fact, the reason Christ came into the world was to conquer death and sin and hell–and He did this by His death and resurrection. When we know Christ, we know that this life is only temporary, and that some day we will go to be with Him in heaven forever. In heaven, "There will be no more death or mourning or crying or pain" (Revelation 21:4).
Let me ask you a question: What are the worst things that might happen to you? Death? Discomfort or pain? Leaving your family behind? Physical weakness? Fear of a recurrence if your cancer is conquered? These are all real, and they have to be faced honestly.
But God wants you to trust Him for the future. Yes, pray for healing. But above all, ask God to help you trust Him, because He loves you and He can be trusted, no matter what happens. Look beyond your cancer to Christ.