Charles, my husband had Cyberknife about 2008. He had a Whipple surgery in 2006 and the CC returned 2 years later. Because if the CC location he could not do Chemo and they felt Cyberknife would be better over radiation. It really was a breeze over the other choices. CK nailed it and he was again Cancer free a for another 2 years. It is merely laying under an machine like an X Ray machine and let the CK do its work only in the area of the CC, The side effects were very minimal, mostly just some tiredness. We felt it was a pure blessing!!!