If you saw a medically inoperable patient for chemoRT for muscle-invasive bladder cancer who had a congenital recto-urethral fistula, would you deliberately exclude the prostate/prostatic urethra from the target volume?

First, I would want to know about this fistula and why it couldn't be addressed when the patient was a child (what other medical factors might be involved?).  Also, the exact location of the fistula would help inform a response to this question.  Finally, the nature and location  of  the bladder tumor i.e. anatomic location in bladder and is the tumor  more defined/localized vs more of field effect seen on pathology sampling.  Be that as it may, reasonable  bladder fields tend towards organ targeting of the primary, so trimming the fields away from the prostate and prostatic urethral area may be clinically possible.