IMRT….again?

Hell all;
I just got back from MD Anderson where I was told my tumor had shrank but it was slightly more FDG avid. I am currently on Itrinotecan every two weeks. Dr. Javle at MD Anderson (after meeting with a group on doctors to discuss my case in a conference)is suggesting IMRT….for the second time.
Last summer I had the 28 treatments and at first, they thought it didn’t worked but later decided it had made the majority of my mass inside the liver necrotic. Basically it is very low – activity wise. BUT at the dome of the liver there is a spot that is still showing up FDG avid. They would like to do IMRT again for 13 days (just on the spot showing up brighter)…getting it twice a day-once in the am and once in the pm. Has ANYONE or does anyone know anything about doing this. The oncologist said it is not done a lot but they feel it will be of benefit to me. Dr. Das, the oncology radiologist says they HAVE did this in the past as MD Anderson but not ALOT. Dr. Javle has tried to get the oncology team to agree to do the IMRT for the past 6 months but since it shrank a little more this time, the oncology team is ready to say yes (the shrinkage made the tumor a little further away from my heart). They say NOW is the time. My CA 19-9 is at 19…..3 months ago, it was about 24.6. I am confused and worried about scar tissue….heart damage….any additional info or comments is appreciated.