Lymphocytes are part of the normal defence system of the body.
Lymphomas are potentially life threatening. Hodgkin's disease most commonly presents with painless swelling of the lymph glands which continues for some weeks or months. The first glands to be affected are often in the neck or in the area above the collar bone. Where glands in the chest are affected, a troublesome cough or breathlessness may be apparent. Initially the swelling is painless.