petrolatum(PEH-troh-LAY-tum) A thick, greasy, substance with no odor or taste made from petroleum.
petroleum jelly(peh-TROH-lee-um â¦) A thick, greasy, substance with no odor or taste made from petroleum.
Peutz-Jeghers syndromeA genetic disorder in which polyps form in the intestine and dark spots appear on the mouth and fingers.
PF-00299804A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called protein tyrosine kinase inhibitors.
PF-3512676A substance that is being studied in the treatment of some types of cancer. It belongs to the family of drugs called biological response modifiers.
PGOne of several hormone-like substances made by the body. Different PGs control blood pressure, contraction of smooth muscles, and other processes within…
PGE1A drug that is used to treat impotence (inability to have an erection) and is being studied in the treatment of sexual problems in men who have had…
PHA-739358A substance being studied in the treatment of chronic myelogenous leukemia. PHA-739358 may stop tumor growth by blocking certain enzymes needed for cancer…
PhagocyteAn immune system cell that can surround and kill microorganisms and remove dead cells. Phagocytes include macrophages.
phagocytosis(FA-goh-sy-TOH-sis) The process by which a phagocyte (a type of white blood cell) surrounds and destroys foreign substances (such as bacteria) and removes…
phantom limb painThe sensation of pain or other unpleasant feelings in the place of a missing (phantom) limb.
pharmacokinetics(FAR-muh-koh-kih-NEH-tix) The activity of drugs in the body over a period of time, including the processes by which drugs are absorbed, distributed in the…
pharmacology(FAR-muh-KAH-loh-jee) The study of the origin, chemistry, and uses of drugs and their effects on the body.
pharmacopoeiaA book describing chemicals, drugs, and other substances and how they are used as medicines. It is prepared by a recognized authority.
pharyngeal cancer(fuh-RIN-jee-ul KAN-ser) Cancer that forms in tissues of the pharynx (the hollow tube inside the neck that starts behind the nose and ends at the top of…
pharynx(FAIR-inks) The hollow tube inside the neck that starts behind the nose and ends at the top of the trachea (windpipe) and esophagus (the tube that goes to…
phase I detoxificationA process in which the liver uses one of two major enzyme pathways to change a toxic substance, such as an anticancer drug, into a less toxic substance…
phase I trialThe first step in testing a new treatment in humans. These studies test the best way to give a new treatment (for example, by mouth, intravenous infusion…
phase I/II trialA trial to study the safety, dosage levels, and response to a new treatment.
phase II detoxificationA process in which the liver uses one of two major enzyme pathways to change a toxic substance, such as an anticancer drug, into a less toxic substance…
phase II trialA study to test whether a new treatment has an anticancer effect (for example, whether it shrinks a tumor or improves blood test results) and whether it…
phase II/III trialA trial to study response to a new treatment and the effectiveness of the treatment compared with the standard treatment regimen.
phase III trialA study to compare the results of people taking a new treatment with the results of people taking the standard treatment (for example, which group has…
phase IV trialAfter a treatment has been approved and is being marketed, it is studied in a phase IV trial to evaluate side effects that were not apparent in the phase…
phenethyl isothiocyanateA substance being studied in the prevention of cancer. It is a naturally occurring compound found in some cruciferous vegetables. Also called PEITC.
phenobarbitalA drug that is used to treat seizures and as a sedative. It is being studied in the treatment of diarrhea and for its ability to increase the antitumor…
phenol(FEE-nol) A very poisonous chemical substance made from tar and also found in some plants and essential oils (scented liquid taken from plants).
phenothiazine(FEE-noh-THY-uh-zeen) A type of drug that is used to treat severe mental and emotional disorders, severe nausea and vomiting, and certain other conditions.
phenoxodiolA substance that is being studied in the treatment of cancer. It belongs to the family of drugs called signal transduction inhibitors.
phenylacetateA substance that is being studied in the treatment of cancer.
phenylbutyrateA substance that is being studied in the treatment of cancer. It belongs to the family of drugs called differentiating agents.
phenylketonuria(FEH-nil-KEE-tone-yoor-ee-uh) An inherited disorder that causes a build-up of phenylalanine (an amino acid) in the blood.
pheochromocytoma(FEE-oh-KROH-moh-sy-TOH-muh) Tumor that forms in the center of the adrenal gland (gland located above the kidney) that causes it to make too much…
pheresis(fer-E-sis) A procedure in which blood is collected, part of the blood such as platelets or white blood cells is taken out, and the rest of the blood is…
Philadelphia chromosome(FIH-luh-DEL-fee-uh KROH-muh-some) An abnormality of chromosome 22 in which part of chromosome 9 is transferred to it.
philosophical(FIH-luh-SAH-fih-kul) Having to do with the deeper questions of life and with a person's basic beliefs, ideas, and attitudes.
phlebitis(fleh-BY-tis) Inflammation (redness, swelling, pain, and heat) of a vein, usually in the legs. Phlebitis may be caused by infection, injury, or irritation.
phlebotomy(fleh-BAH-toh-mee) The puncture of a vein with a needle for the purpose of drawing blood. Also called venipuncture.
phlegm(flem): Thick mucus from the airways of the body.
phlegm (flem)A more than normal amount of thick mucus made by the cells lining the upper airways and lungs.
phobia(FOH-bee-uh) An extreme, irrational, fear of something that may cause a person to panic.
phosphate(FOS-fayt) A substance that contains phosphorus, a nonmetal chemical element. Phosphate may be used to treat a high level of calcium in the blood.
phospholipidA lipid (fat) that contains phosphorus. Phospholipids are a major part of cell membranes.
phospholipid complexA chemical or drug that is attached to a lipid (fat) that contains phosphorus.
phosphoric(FOS-for-ric) Having to do with or containing the element phosphorus.
phosphorus(FOS-for-us) A nonmetallic element that is found in the blood, muscles, nerves, bones, and teeth and is a component of adenosine triphosphate (ATP; the…
phosphorus-32A radioactive form of phosphorus used in the treatment of cancer. It is also used to help locate areas of DNA damage.
photoactivityThe effect produced when certain substances are exposed to light. In cancer treatment, some drugs become active when exposed to light and are then able to…
photocoagulation(FOH-toh-koh-A-gyuh-LAY-shun) The use of an intense beam of light, such as a laser, to seal off blood vessels or destroy tissue.
photodynamic therapy(FOH-toh-dy-NA-mik THAYR-uh-pee) Treatment with drugs that become active when exposed to light. These activated drugs may kill cancer cells.
Photofrin(FOH-toh-frin) A drug used to treat some types of cancer. When absorbed by cancer cells and exposed to light, Photofrin becomes active and kills the…
photon-beam radiation(FOH-ton beem RAY-dee-AY-shun) A type of radiation therapy that reaches deep tumors with high-energy x-rays made by a machine called a linear accelerator.
photopheresis(FOH-toh-fuh-REE-siss) A procedure in which blood is removed from the body and treated with ultraviolet light and drugs that become active when exposed to…
photophobia(FOH-toh-FOH-bee-uh) A condition in which the eyes are more sensitive than normal to light.
photosensitizer(FOH-toh-SEN-sih-ty-zer) A drug used in photodynamic therapy. When absorbed by cancer cells and exposed to light, the drug becomes active and kills the…
photosensitizing agent(FOH-toh-SEN-sih-ty-zing...) A drug used in photodynamic therapy. When absorbed by cancer cells and exposed to light, the drug becomes active and kills…
phototesting(FOH-toh-TES-ting) Special tests used to measure the reaction of the skin to ultraviolet radiation.
phototherapy(FOH-toh-THAYR-uh-pee) The treatment of disease with certain types of light. Phototherapy can use lasers, LED, fluorescent lamps, and ultraviolet or…
phototoxicity(FOH-toh-tok-SIH-sih-tee) A condition in which the skin or eyes become very sensitive to sunlight or other forms of light.
phyllodes tumor(fih-LOH-deez TOO-mer) A type of tumor found in breast or prostate tissue. It is often large and bulky and grows quickly.
physiatrist(fih-ZY-uh-trist) A doctor who specializes in physical medicine (the prevention and treatment of disease or injury with physical methods, such as exercise…
Physical Dependence(FIH-zih-kul dee-PEN-dents) A condition in which a person takes a drug over time, and unpleasant physical symptoms occur if the drug is suddenly stopped…
physical medicine specialist(FIH-zih-kul MEH-dih-sin SPEH-shuh-list) A doctor who specializes in physical medicine (the prevention and treatment of disease or injury with physical…
physical therapistA health professional who teaches exercises and physical activities that help condition muscles and restore strength and movement.
physical therapy(FIH-zih-kul THAYR-uh-pee) The use of exercises and physical activities to help condition muscles and restore strength and movement.
Physician Data QueryPhysician Data Query is an online database developed and maintained by the National Cancer Institute.
physiologic(FIH-zee-uh-LAH-jik) Having to do with the functions of the body. When used in the phrase "physiologic age," it refers to an age assigned by general…
phytic acid(FY-tik A-sid) A substance found in many foods that come from plants, including corn, wheat, rice, and soybeans, and in large amounts in cereals and…
phytochemical(FY-toh-KEH-mih-kuhl) A substance found in plants. Some phytochemicals may reduce the risk of cancer.
phytoestrogenAn estrogen-like substance found in some plants and plant products. Phytoestrogens may have anticancer effects.
phytohemagglutinin(FY-toh-HEE-muh-GLOO-tih-nin) A substance found in plants that causes red blood cells to clump together and certain white blood cells to divide.
phytol(FY-tol) A chemical substance that comes from plants and is used to make vitamins E and K.
phytosterolA plant-based compound that can compete with dietary cholesterol to be absorbed by the intestines, resulting in lower blood cholesterol levels.
PI-88A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antiangiogenesis agents.
PI3 KinaseA type of enzyme that transmits signals in cells and that helps control cell growth. Some tumors have higher-than-normal levels of PI3 Kinase.
PI3KA type of enzyme that transmits signals in cells and that helps control cell growth. Some tumors have higher-than-normal levels of PI3K.
pigmentA substance that gives color to tissue. Pigments are responsible for the color of skin, eyes, and hair.
pilocarpineA drug used to increase salivation in people who have dry mouth caused by opioids or radiation therapy.
pilocytic(PI-lo-SIT-ik) Made up of cells that look like fibers when viewed under a microscope.
pilot studyThe initial study examining a new method or treatment.
PINNoncancerous growth of cells lining the internal and external surfaces of the prostate gland.
pineal bodyA tiny organ in the cerebrum that produces melatonin. Also called pineal gland and pineal organ.
pineal gland(PIN-ee-al) A tiny organ in the cerebrum that produces melatonin. Also called pineal body and pineal organ.
pineal organA tiny organ in the cerebrum that produces melatonin. Also called pineal body and pineal gland.
pineal region tumor(PIN-ee-al...) A type of brain tumor that occurs in or around the pineal gland, a tiny organ near the center of the brain.
pineoblastoma(PIN-ee-oh-blas-TOH-muh) A fast growing type of brain tumor that occurs in or around the pineal gland, a tiny organ near the center of the brain.
pineocytoma(PIN-ee-oh-sy-TOH-muh) A slow growing type of brain tumor that occurs in or around the pineal gland, a tiny organ near the center of the brain.
pinkeyeA condition in which the conjunctiva (membranes lining the eyelids and covering the white part of the eye) become inflamed or infected.
pioglitazone(py-oh-GLIH-tuh-zone) A drug that is used to treat type 2 diabetes and is being studied in the prevention of head and neck cancer.
piperacillin-tazobactamA drug combination that is used to treat infection in people with cancer. Piperacillin is a synthetic penicillin; tazobactam enhances the effectiveness of…
pirfenidoneA substance that is being studied in the prevention and treatment of scar tissue caused by radiation therapy.
Piritrexim(peer-ee-TREX-im) A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called folate antagonists.
Pituitary gland(pih-TOO-ih-TAYR-ee...) The main endocrine gland. It produces hormones that control other glands and many body functions, especially growth.
pituitary tumor(pih-TOO-ih-TAYR-ee TOO-mer) A tumor that forms in the pituitary gland. The pituitary is a pea-sized organ in the center of the brain above the back of…
pixantroneA substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antitumor antibiotics. Also called BBR 2778.
PJSA genetic disorder in which polyps form in the intestine and dark spots appear on the mouth and fingers.
PKCAn enzyme found throughout the body's tissues and organs. Several forms of PKC are involved in many cellular functions.