Lymphoma is a type of cancer which affects our lymphatic system. This is a network of vessels which runs throughout our body and helps to carry immune cells like white blood cells, waste, and water. It has an important role in our immune system.
Lymphoma happens when a type of white blood cell called a lymphocyte does not develop properly. The cells begin to divide out of control and clump together to form solid lumps. Tumours most commonly form in the lymph nodes but they can form in other parts of the body too.
Lymphomas are usually classed as Hodgkin lymphoma or non-Hodgkin lymphoma, depending on the type of cell that is affected. Hodgkin lymphoma is more rare in the general population, but is one of the most common cancers diagnosed in younger people.