Diffuse Large B-Cell Lymphoma (DLBCL or DLBL) is a cancer of B cells, a type of white blood cell responsible for producing antibodies. It is the most common type of non-Hodgkin lymphoma among adults. It usually grows in the lymph nodes – the pea-sized glands in your neck, groin, armpits, and elsewhere that are part of your immune system. Depending on diagnosis, Bone Marrow transplant may be required to treat this disease.