About Hodgkin lymphoma

Hodgkin lymphoma (also known as Hodgkin's disease) is cancer that develops in lymphocytes. These are cells in the lymphatic system, a network of vessels, nodes and organs that filter waste and toxins and help fight infection. The spleen, thymus, tonsils and bone marrow form part of the lymphatic system, which also includes about 650 lymph nodes scattered throughout the body.

The main types of lymphocytes are T-cells and B-cells, which are white blood cells made in bone marrow. B-cells remain in the bone marrow to mature, while T-cells mature in the thymus, a small organ nestled between the lungs.

The two main types of T-cells are:

• Killer T-cells, which destroy cells that have been infected or damaged
• Helper T-cells, which stimulate B-cells to make antibodies that attack infections and viruses

B-cells are far more likely than T-cells to mutate and cause a liquid cancer such as Hodgkin lymphoma, non-Hodgkin lymphoma or leukemia.

The main difference between Hodgkin lymphoma and non-Hodgkin lymphoma is the presence or absence of oversized B-cells called Reed-Sternberg cells. These cells are usually detected during a biopsy and indicate the presence of Hodgkin lymphoma. Hodgkin lymphoma is considered rare. The American Cancer Society estimates that 8,480 new cases of the disease will be diagnosed in the United States in 2020, with 4,690 occurring in men and 3,790 occurring in women. Among lymphomas, Hodgkin lymphoma is much less common than non-Hodgkin lymphoma, which is the seventh most common type of cancer in the United States.

Although Hodgkin lymphoma can occur at any age, it is most common between the ages of 55 and 84.

Next topic: What are the risk factors for Hodgkin lymphoma?