It doesn't matter if it kills cancer cells or not if it's unsafe for the patient to have the procedure done as well as unsafe for the medical staff providing the treatment- not to mention handling and disposal safety issues.
I do believe radiogel is a good cancer killing idea but until amic can prove its a safe treatment the risks do not outweigh the rewards. Thats EXACTLY WHAT THE FDA SAYS.
fda says "We do not believe that the benefits of your device outweigh the risks "