Hi Raj,
I had exactly the same cancer in the cheek seven years ago. My surgery was on March 27 and I did not start radiation until May 20th through July 3rd. Your sisters skin has to heal because radiation will burn her skin. So be patient. I do not have time right now to write more about my case; but I just want to let you know, that you have to trust her doctors about radiation treatment. If they took her cheek out, even her outer skin, it means that they were careful to make sure the cancer was removed. In my case, my cancer was at the beginning stage, so my doctor did not remove my outer skin. I was lucky. Loli