There are no vaccines for leukemia. My Father died of leukemia in 1993. He was diagnosed 1 year prior to that and did the whole chemo thing along with the rest of the protocol. That being said, approx. 9 years prior to being diagnosed with leukemia, he had prostate cancer in which he took the maximum amount or radiation for that. In 1992, his Oncologist told him that his acute leukemia was most likely brought on by the maximum radiation he had all those years in the past. Also, in that one year that he lived between his diagnosis of leukemia and his death, he had only 4 months of remission, and those other 8 months were HELL. Of course, things have probably come a long way since the 90's, BUT that doesn't mean that a person will 100% be absolutely cured for the rest of their life. Honestly, most things in life are a "crap shoot" no matter how much medicine has advanced through the years.