laparoscopy [lap-a-ros-co-py], laparoscope [lap-a-ro-scope] The process of looking into the abdomen using a laparoscope in order to establish a diagnosis, particularly of liver , bowel and pelvic conditions: see endoscopy , fibre optics .

large bowel Consists of the colon and rectum : see bowel. Also called large intestine.

large cell carcinoma A type of lung cancer that usually develops in the airways and is characterised by large rounded cells . It accounts for about 16 per cent of all lung cancers.

laryngeal carcinoma [la-ryn-ge-al car-ci-no-ma] Cancer of the larynx . This is considerably more common in men than in women. Most cancers of the larynx occur on the vocal cords ; hoarseness is an early symptom. Many can be cured if diagnosed at an early stage: see laryngectomy .

laryngectomy [la-ryn-gec-to-my] A total laryngectomy is the surgical removal of the larynx or voice box . A partial laryngectomy is the removal of part of the larynx: the voice is preserved, though it may be slightly changed.

larynx [la-rynx] The voice box , or Adam's apple, which sits in the front of the neck. It contains the vocal cords. During swallowing, the vocal cords close together to prevent food and saliva entering the windpipe. They also vibrate together to produce voice.

laser An instrument that produces an intense beam of light used in surgical procedures. It can work on a very small area with great precision without damaging surrounding tissue. It can be used to remove abnormal cells .

lesion [le-sion] Any abnormality in tissues of the body caused by disease or injury.

leucocyte (or leukocyte) [leu-co-cyte] see white blood cell .

leukaemia [leu-kae-mi-a] Cancer that affects the bone marrow and organs that manufacture blood (lymph nodes, spleen). In leukaemia, large numbers of abnormal white blood cells (known as leukaemic blasts) are produced, and this suppresses the production of normal blood cells . Leukaemia may be acute , progressing rapidly over days or weeks, or chronic , progressing slowly over months or years: see white blood cells .

lipoma [lip-o-ma] A soft, fatty benign tumour (not a cancer ) that lies directly under the skin . Lipomas may be very small or as big as a grapefruit, and are very common. They are sometimes removed for cosmetic reasons.

liver cancer Cancer that begins in the liver is uncommon in Australia. Treatment may be surgery and/or chemotherapy . However it is common to find secondary tumours (metastases ) in the liver, that is, cancers that have spread to the liver from another part of the body. These 'liver secondaries' are not true liver cancers, and treatment will depend on the site and type of the primary or original cancer.

liver function tests A simple blood test that gives information about how the liver is functioning.

liver scan A test used to discover the size, shape and position of the liver and to detect any tumours : see nuclear medicine .

lobe A major division of an organ of the body, often separated from other lobes by deep splits. The liver is made up of four lobes, the right lung has three lobes, and the left lung, two.

lobectomy [lo-bec-to-my] The surgical removal of a lobe of the liver or a lung.

lobular cancer [lob-u-lar can-cer] A breast cancer that starts in the milk sacs in one of the lobes of the breast .

local excision The surgical removal of a localised cancer , that is, one that has not spread beyond its original site: see lumpectomy .

local invasion see infiltration .

local recurrence see recurrence .

lumbar puncture A diagnostic test in which a sample of cerebrospinal fluid is taken from the area around the spinal cord and examined under the microscope. The fluid may show evidence of tumour , infection, or inflammation in the central nervous system .

lumbar spine The section of backbone in the small of the back, just above the buttocks.

lumpectomy [lump-ec-to-my] The surgical removal of a lump, particularly in relation to breast cancer to describe the removal of a breast lump with some of the surrounding healthy tissue, without removing the whole breast : see local excision .

lumpy breast disease see benign fibrocystic changes .

lungs The two sponge-like, pinkish-grey organs in the chest cavity. The lungs wrap around the heart and the oesophagus . Air enters the lungs via the windpipe. Oxygen processed from this air passes into the bloodstream. See Diagram 2 .

lung cancer Cancer that starts in the lung or in the lining of the air passages leading to the lung. There are several different types of lung cancer that are named according to the type of cell involved.

lung function tests see pulmonary function tests .

lymph A clear fluid that contains white blood cells , antibodies, and wastes carried from the body tissues, lymph is present throughout the body in a network of lymphatic vessels.

lymph glands see lymph nodes .

lymph nodes Small bean-shaped structures scattered along the lymphatic vessels, particularly in the neck, armpit and groin. They filter the lymph to remove bacteria and other harmful agents to prevent them from entering the bloodstream. Lymph nodes also produce lymphocytes, a type of white blood cell . Also called lymph glands (although they are not true glands ). Lymph node negative test results show no cancer cells in the lymph nodes. Lymph node positive test results show that cancer cells are present in the lymph nodes.

lymph tissue see lymphoid tissue .

lymphatic system, lymphatic vessels The lymphatic system is part of the immune system, which protects the body against 'invaders', like bacteria and parasites. The lymphatic system is a network of small lymph nodes connected by very thin lymph vessels, which branch into every part of the body.

lymphocyte A type of white blood cell formed in lymph nodes. It is part of the body's immune system which helps to fight infection.

lymphoedema [lymph-oe-de-ma] Swelling caused by a buildup of lymph ; this happens when there is a insufficient draining in lymphatic vessels or lymph nodes , and can occur following some cancer treatments.

lymphoid tissue [lym-phoid] Tissue where lymphocytes and antibodies are made. The lymph nodes , tonsils, thymus and spleen are made up of lymph tissue; it also forms part of other tissues. It is important in fighting infection. Also called lymph tissue.

lymphoma [lym-pho-ma] Lymphomas are divided into two major types: Hodgkin's disease and non-Hodgkin's lymphoma. Most arise in a lymph node, but sometimes a non-Hodgkin's lymphoma may begin in lymph tissue in the stomach, bone or small intestine. Some non-Hodgkin's lymphomas tend to appear simultaneously in several parts of the body.