it is kind of funny in a horrible, ironic way that you would see in a movie or a cartoon. i know sorry doesn't help much but i am genuinely sorry that life slapped you with this irony. i don't know what its like to live with cancer, but from what i hear cancer is really painful and the treatments can get expensive.
i knew a friend who saw two blood linked relatives pass away from cancer. one, they told me, was really painful to watch because they saw their brain slipping away from them.
i don't mean to say any of these things to scare you. what do you think you want to do now? what are your viable options? (you don't have to answer if you don't want to.)