What dose do you use for postoperative rectum boost?

To the best of my knowledge there is no good information on this topic. I rarely use post RT nowadays. However, when I do, I have not gone higher than 54 Gy when it is truly an adjuvant treatment, and I often stopped at 50.4 Gy. The main limiting factor is toxicity, both small bowel and residual rec...

We use 50.4Gy and very rarely go to 54Gy.

max point dose of 65Gy and <40 cc over 55Gy (guideline not limit).

We use 54Gy as well, but limit the small bowel dose to max point dose of 55Gy and <40 cc over 45Gy (guideline not limit). Often IMRT is necessary due to fixed small bowel in the pelvis. It is important to be very cautious with apparently fixed small bowel in the pelvis.