If you agree to take part in this study, the way you participate will depend on if you are being treated for cancer. If you are receiving any form of chemotherapy, you will have about 4 1/2 tablespoons of blood drawn before you start the first day of treatment. You will then have about 3 tablespoons of blood drawn every 6 to 8 weeks for the next 6 months. You will have a total of up to about 5 blood draws for this portion of the study. You will have the above blood draws during routine visits so that no additional visits will be required.