Additional Study Information: The purpose of this study is to study the impact of stem cell dose on outcome after autologous transplant. An autologous transplant is infusion of your own bone marrow cells (stem cells) following a high-dose of chemotherapy. Autologous transplant is the standard treatment for relapsed Diffuse Large B-Cell Lymphoma (DLBCL) or DLBCL that did not respond to initial chemotherapy. The treatment is meant to keep your lymphoma from coming back. Previous studies have suggested that the amount of your stem cells that you get at transplant may effect outcomes. This has not been proven in a randomized study.