Good luck with your Cat Scan. I am also on Sutent, 3rd cycle, and awaiting a Scan soon to see if it is working. It is a very anxious place to be. My side effects have been limited to sore feet and hands. I am taking 37.5 mg after 2 cycles of 25 mg. I don't know if I could handle 50 mg., which is the standard dose, and probably the most effective. If it is working for me, I may try to kick it up another notch. If it is not working for me, I may still try to kick it up a notch. My oncologist and I have not had a discussion about it not working. I have been on Nexavar and Torisel, with some success, but bad side effects.
Good luck with your Cat Scan. Let's hope for better treatments soon.
Richard