Dictionary

Lleptomeninges The arachnoid and pia mater layers of themeninges.lesion [lee´ zhun] An area of abnormal tissue due to disease orinjury.lethargy [leth´ ar gee] Sluggishness, drowsiness, indifference.leukocytes [lou´ ko sitez] White blood cells, includingeosinophils, basophils, mast cells, neutrophils, lymphocytesand monocytes, etc.leukoencephalopathy [loo koe n seff ah lopp´ ah thee]An adverse effect on the white matter of the brain. Can be dueto infection, drugs, radiation, or disease. Symptoms range frommild to severe.Li-Fraumeni syndrome A rare, inherited predisposition tomultiple cancers including brain tumors. It is caused by analteration in the p53 suppressor gene. Abbreviated LFSsyndrome.limbic system The part of the brain involved with behavior,emotion, and the sense of smell. With the hypothalamus, itcontrols hunger, thirst, and biological rhythms.Linac Radiosurgery An adapted linear accelerator that deliversa single, high-energy beam, computer-shaped to the tumor.linear accelerator An electrical device that creates ionizingradiation in the form of x-rays (photons) The higher the voltageof the device, the more penetrating are the x-rays produced.lipoma A rare, benign tumor composed of fat tissue.lobe One of four sections of the cerebral hemispheres.lobectomy [low bek´ toe mee] The surgical removal of one lobeof the brain.local In the area of the tumor; confined to one specific area.Also referred to as localized.local therapy A treatment directed only to the tumor andperhaps a small area beyond it.loss of 1p 19q The combined loss of genetic material onchromosomes 1p and 19q is strongly associated with favorableoutcome in patients with certain types of oligodendroglialtumors (oligodendrogliomas).low-frequency electromagnetic fields Low energy fields,called EMFs, emitted by power lines and household appliances.lower toxicity drugs A generation of chemotherapy drugs withmilder side-effects.LPN Licensed Practical Nurse.LRRFS Local/Regional Recurrence-Free Survival.LSW Licensed Social Worker.lumbar [lum´ bar] The area of the spine between the ribs andthe pelvis (the waist and lower back).lumbar puncture Needle penetration into the subarachnoidspace of the lumbar spine. Used to withdraw a sample of spinalfluid for examination or to to inject a dye into the spine prior toa myelogram. Also called spinal tap.lymph [limf] A transparent, slightly yellow fluid that carrieslymphocytes, bathes body tissues and drains into the lymphaticvessels.lymph nodes [limf] Small bean-shaped organs of the immunesystem, distributed widely throughout the body and linked bylymphatic vessels. Clusters of lymph nodes are found in theunderarms (axilla), groin, neck, chest and abdomen. Also calledlymph glands, although they are not actually glands.lymphatic system [lim fat´ ik] The tissues and organs thatproduce, store and carry white blood cells that fight infectionsand other diseases.L6667