In a patient with localized prostate cancer with rising PSA would you consider EBRT if the patient is also undergoing chemotherapy for active recurrent colon cancer?

Hi. I, generally, agree with @Dr. First Last's response, but I would consider a few other things as well.

For example:

1. Disease extent or tumor burden of the recurrent colon cancer. Is the patient dying soon because of a heavy tumor burden, or does the tumor involve 5 or less metastatic sites, w/o compromised organ system(s) of those involved.

2. The performance status of the patient -> are they sickly, or healthy looking and still active. I ask the patient and family what are they willing do in this regard and in light of the complicated clinical circumstances?

3. Nature of his prostate cancer -> is it a young patient 60yrs or less, is the PC high risk or low risk category, is there irritative prostate issues

So, I have treated a few patients...

If course of colon cancer is not curative would not chase rising PSA for treatment.