Lymphoma is the most common type of blood cancer. It affects the body’s lymphocytes, a type of white blood cell that defends against bacteria and viruses. Lymphomas typically develop because a change or mutation occurs inside a lymphocyte. When a lymphocyte develops cancer, it can travel through the blood and spread to other areas of the body, including the lymph nodes, bone marrow, skin and many other organs.
Non-Hodgkin lymphoma is one of the most common cancers. According to the American Cancer Society, it accounts for about 4% of all cancers in the United States.