Hodgkin lymphoma starts in the lymph system, usually in a lymph node. The disease may be found because of a swollen lymph node in the neck, chest, or other areas.
The disease begins when a lymphocyte (almost always a B cell) becomes abnormal. The abnormal cell divides to make copies of itself. The copies keep dividing, making more abnormal cells that build up.
When white blood cells collect around the abnormal cells, the lymph node that contains abnormal cells becomes swollen. Abnormal cells may spread through the lymph vessels or blood vessels to other parts of the body.
Although normal cells die when they get old or damaged, abnormal cells don’t die. Also unlike normal cells, abnormal cells can’t help the body fight infections.