What does your medical Onc have to say about rads? Having had a lumpectomy, I don't have any experience about what a PS would know about giving you advice about rads or no rads. I think I would have more confidence in an Onc, but again, not sure about that. Would you consider a second opinion from a diffrerent rad onc?
I did have radiation, but also had lymph node involvement. It was also my decision, but one that I was very comfortable with making.
I'm sure you will hear from those with experience.
Go with your gut - it never lies!
HUGS and PRAYERS