radiation induced leukemia usually takes longer to develop so that seems unlikely. Its a little early to say what the actual cause is as other things could cause low platlets. Do you know any other lab results (WBC, Hg/Hb, etc) ? Let us know what the biopsy says. A BMT may or may not be needed in a leukemia patient. Many patients can get into remission with chemo alone and BMT's are usually reserved for refractory/relapsed cases. The best BMT donor is an identical twin, but from there the best HLA match is obtained from a sibling or perhaps from an unrelated donor. Again, its a little early in the game to be worrying too much about such things. Get a disgnosis first and then go from there.