Shirley,
Ask questions!!! Ask what something means. Ask what tumor markers are and what does it mean in your case. If your doctor is that good he'll answer your questions and if you don't understand what he means, tell him and ask him to explain it differently until you do. If he simply can't, ask him to refer you to a nurse that has an understanding of your records and will take the time to help explain what's going on. This is information you need to know insted of being worried about.