Chemotherapy. Drug injected into a catheter in a man's hand, during chemotherapy treatment. The catheter is attached to peripheral line blood vessels. The patient is a 34 year old Down's syndrome man who is suffering from acute myeloid leukaemia. It is a cancer in which an excess of white blood cells are produced, which play a role in the body's immune system. People with Down's syndrome suffer from a higher-than-average incidence of acute leukaemia. Chemotherapy treatment usually involves administration of cyto- toxic drugs given intravenously.