Lymphoma is a type of cancer that starts in cells of the lymphatic system, which is part of the body's immune system. The lymphatic system includes the lymph nodes (small bean-shaped glands), lymphatic vessels, and other organs like the spleen, thymus, and tonsils.
There are two main types of lymphoma: Hodgkin lymphoma and non-Hodgkin lymphoma. Hodgkin lymphoma, also called Hodgkin's disease, is characterized by the presence of a specific cell called Reed-Sternberg cells.
