Non-Hodgkin’s lymphoma is cancer of the lymphatic system. The lymphatic system is the body’s natural defence against infection. It is made up of a collection of lymph glands (nodes) which are situated throughout the body in the neck, armpits, chest, abdomen and groin. Tiny vessels (tubes) connect these glands. The tonsils and spleen (which breaks down old blood cells) are also part of the lymphatic system.