When treating bladder cancer with 55 Gy in 20 fractions, what small bowel dose constraints do people use?

Yes, it is hard to tell what happened on that trial because we don't know how often small bowel might have been excluded from the PTV. It would be nice to hear from others, like @Dr. First Last. And maybe theMednet can get Dr. James to join?

For what it is worth, when this is an issue, I treat with...