My mom has Stage 4 Non-Hodgkin's T-Cell Lymphoma. She's going to have to do a strong chemo this time. Her doctor told her, because of which she'll need a bone marrow transplant. They want to use her bone marrow first, and if that doesn't work, test her kids and siblings. What I'm wondering is, if she has the cancer in her bone marrow, how can they use her bone marrow? Wouldn't that be putting the cancer back in her?