Understanding Hodgkin Lymphoma: What is Hodgkin Lymphoma?

To understand Hodgkin lymphoma, it’s first important to understand what cancer is: basically, the production of abnormal cells.

The body is programmed to routinely replenish cells in different organs. As normal cells age or get damaged, they die off. New cells take their place. This is what’s supposed to happen. Abnormal cell growth refers to a buildup of extra cells. This happens when:

  • New cells form even though the body doesn’t need them or
  • Old, damaged cells don’t die off.

These extra cells slowly accumulate to form a tissue mass, lump, or growth called a tumor. These abnormal cells can destroy normal body tissue and spread through the bloodstream and lymphatic system.

About Hodgkin Lymphoma

Your immune system fights off infections and other diseases. Hodgkin lymphoma is a cancer that begins in the cells of your immune system. To understand this form of cancer, it’s helpful to understand how your immune system works.

Your immune system is complex. It consists of many interacting parts, including:

  • white blood cells called lymphocytes
  • a network of lymph nodes and connecting vessels called the lymphatic system
  • lymphoid organs like the tonsils, thymus  and spleen

Lymph nodes, which are composed almost entirely of lymphocytes, exist throughout the entire body. They play a critical role in ‘educating’ lymphocytes on how to fight infection. There is also lymphatic tissue in other parts of your body, like your stomach, skin and small intestine.

Because lymphatic tissue is in many parts of the body, Hodgkin lymphoma can start almost anywhere. Usually, it's first found in a lymph node above your diaphragm. This is the thin muscle between your chest and your abdomen. Hodgkin lymphoma can also be found in a group of lymph nodes or in other parts of the lymphatic system.

According ot the National Cancer Institute (NCI), there were about 8,500 new cases of Hodgkin lymphoma in the U.S. in 2016.

The Way Hodgkin Lymphoma Progresses

Hodgkin lymphoma develops when a lymphocyte becomes abnormal. That abnormal cell is called the Reed-Sternberg cell. This cell divides and gives rise to new dividing abnormal cells.   This process causes more and more abnormal cells to exist. What makes Hodgkin lymphoma unusual, is that the abnormal Reed-Sternberg cells sends out messengers that attract millions of normal cells.  For this reason, most of the cells in a Hodgkin lymphoma tumor are actually normal.  This buildup of abnormal Reed-Sternberg cells and normal cells creates a mass of tissue. This is called a tumor or growth.

There are 2 main types of Hodgkin lymphoma:

  • Classical: This is the most common kind of Hodgkin lymphoma.
  • Nodular lymphocyte-predominant Hodgkin lymphoma: This kind is rare, and treated very differently.  It’s important that your doctor find out which kind of Hodgkin lymphoma you have to plan the appropriate treatment.

Next: How is non-Hodgkin Lymphoma diagnosed?

Return to "Hodgkin Lymphoma: An Introduction."