Most cases in node negative mastectomy, radiation is NOT indicated. I'd be shocked if it is recommended in your case, and would seek a 2nd opinion if it is. It is not without risks of side effects and unless your tumor sat up against the chest wall, I doubt it's truly necessary.

My diagnosis was Stage 0, DCIS. I had a lumpectomy, radiation treatments and am now taking Tamoxifen. Think of the radiation treatments as additional insurance. The side effects are more noticeable towards the end. That is when the fatigue sets in and burns begin to surface. It takes time to recover from radiation treatment. More than most people realize.

I had a lumpectomy and a spec was found on one node. I had chemo and radiation. Radiation wasn't too bad. It just really makes you tired. I finished two weeks ago and still have overwhelming fatigue. I nap for a long time every day. To me, do it so you have no regrets and you did everything possible to prevent recurrence. Good look with whatever you decide.

I too had a mastectomy with clear margins. I had 4 rounds of chemo, but no radiation. I was told as long as the margins were clear and no lymph node involvement, radiation was unneccesary

Seek a second opinion. The standard protocol is to radiate, no matter what - but there are serious side effects, consequences, and quality of life issues to consider. For example: radiating the chest poses a large risk of heart failure years down the road, and can make any reconstruction on that skin very hard to perform. I chose not to radiate, and am pleased with my decision - but every cases is different and should be undertaken with the advice and support of a trusted oncologist.