Cancer of the lymphatic system is known as lymphoma. Lymphoma originates in the cells called lymphocytes (a type of white blood cell). The lymphoma can affect any part of the lymphatic system (the lymph nodes, thymus gland, tonsils, spleen, and bone marrow). The lymphatic system comprises a series of lymph nodes and vessels that carry a fluid called lymph. The lymph fluids contain the infection-fighting cells called lymphocytes. Lymph fluid passes through the lymph nodes, which filter, capture, and destroy the bacteria and viruses to prevent the infection from spreading.