having worked with and around radioactivity in a medical lab for 3 years, my first answer would be no. that person is not in danger of radioactivity. as someone stated before, you would have to be subject to radioactivity exposure for ample amount before you would be in danger. afterall, almost all appliances emit some sort of radioactivity continually, and we live with it all our lives. okay, i'm getting sidetracked.
as with others who said so already, best advice would be given from qualified professionals, who would be people in medical field, not from androidtech members. but i understand your concern, i probably would banter away on some message board if that helped. oh, and this mom who has the tumor.... she has a tumor and taking radioactivity as a treatment... sound to me like it indeed is cancerous. if it was benign, couldn't they just go in and take it out? i don't know what the diagnosis is exactly, but ingesting radioactivity is pretty heavy duty. but then again, i'm not a doctor and that's why i'm on here posting.