Introduction According to the American Cancer Society website, Non-Hodgkin lymphoma (also known as non-Hodgkin’s lymphoma, Non-Hodgkin’s disease, NHL, or sometimes just lymphoma) is a cancer that starts in the cells of the lymph system, which is part of the body’s immune system.1 It is a type of cancer of the blood that affects the white blood cells, which are usually involved in protecting against infections. NHL is not a single disease, but rather a group of at least 31 closely related cancers that affect the lymphatic system.2 Although the different types of NHL have some things in common, particularly their lymphatic origin, they differ in their appearance under the microscope, their molecular features, their growth patterns and their impact on the body.2
Pertinent Anatomy and Lymphatics
Figure 1: The Lymphatic System [pic] Adapted image from http://lymphoma-faq.org/images/lymphatic_system.jpg The lymphatic system (Figure 1), the target of lymphomas, includes the lymph nodes and other organs that make up the immune and blood-forming (hematopoietic) elements of the body. The lymph nodes are oval, pea-sized organs. They are found beneath the skin along the route of the large blood vessels, and they are grouped in areas such as the neck, underarms, groin, abdomen and pelvis. The lymph nodes are linked throughout the body by narrow tubes known as the lymphatic vessels. The vessels carry lymph from the body’s tissues; chyle, the fluid from the intestines during digestion; lymphocytes, the specialized white blood cells; and other blood cells. The lymphatic fluids and lymphocytes ultimately are funneled back into the bloodstream through a connection in the left upper chest. Other organs that contain lymphatic tissue and are also affected by lymphomas include the spleen, thymus gland, bone marrow, and the tonsils. Non-Hodgkin’s lymphomas begin in the lymphatic tissues, the white blood cells