PHOTON THERAPY IS JUST EMERGING AS A GOOD CANCER TREATMENT, after many years of investigation at Harvard Medical School, Mass General Hospital and other places. Unlike other particle therapy, it can be focused and does not burn through the skin on the way in, nor travel beyond the target tumor, leading to much less side effects. The capital investment is enormous because it needs a Synchrotron to generate the beam which is rotated completely around the patient to hit the 3D image of the tumor. In 2010 several centers worldwide came online.