What Is It?

Hodgkin lymphoma is a cancer of the immune system. It is also called Hodgkin disease. Hodgkin lymphoma is one of the most curable forms of cancer. It begins in the part of the immune system called the lymph system. The lymph system is made up of an intricate network of immune cells, small blood-vessel-like structures called lymphatics, and lymph nodes. It also includes organs made primarily of immune cells such as the spleen and thymus gland. The lymph (or lymphatic) system helps fights infections and other diseases.

The lymph system includes:

• Lymph: A clear fluid that carries white blood cells (especially lymphocytes) through the lymph system. White blood cells help fight infection.

• Lymph vessels (lymphatics): A network of thin tubes. They carry lymph from different parts of the body to the bloodstream.

• Lymph nodes: Small masses of tissue that store white blood cells. They also remove bacteria and other substances from the lymph. Lymph nodes reside throughout the body, including the neck, underarms, chest, abdomen, pelvis, and groin.

• Spleen: An organ near the stomach that:

• Makes lymphocytes

• Filters the blood

• Stores blood cells

• Destroys old blood cells

• Thymus gland: a gland located in the central portion of the chest near the heart. The gland consists of lymphocytes that are important in immune function especially in children and young adults

The lymph system also consists of the thymus, tonsils, and bone marrow and gastrointestinal tract.