Hi Shat, I think it's probably 50-50 as to whether your boob shrinks after radiation. I know any ladies who had no changes in their breasts at all. I'll be honest with you - my boob shrunk abit and was uncomfortable, hard forever after. My husband and I couldn't touch it and it basically was there to fill a bra which was ok by me.However,7 years later the cancer came back in the same spot and I had to have a mastectomy.I was told I had an 8% chance of recurrence in the same breast - lucky me!Prepare for worst but hope for the best,has become my motto.You've come this far so stay hopeful.Tonya xx