In training, I was taught that IMRT may be justified in rectal cancer with T4 disease, because a greater volume of bowel was treated when the field was extended anteriorly, and that seems to make sense. Overall, more people are using IMRT for rectal cancer patients, but it doesn't seem to coincide w...

I have no doubt that when treating the external iliac nodes, IMRT has benefit.  There is a very old study by Gallagher that looked at 2D planning for pelvic malignancies planned in different positions after different types of surgery.  The volume of bowel was estimated using contrast, but ...