Needing some advice

Definitely go for the interview.  Radiation is annoying in that you have to go every day, and it can make you quite tired, but it is only for a few weeks so it shouldn't stop you from working.  I didn't work during my treatment which was lumpectomy, mastectomy, chemo then radiation, but I went back within a couple of weeks of radiation finishing.  I think if it had been rads only rather than chemo as well, I probably wouldn't have been off work.