Cancer Glossary » P

P-32 A radioactive form of phosphorus used in the treatment of cancer.

p-value A statistics term. A measure of probability that a difference between groups during an experiment happened by chance. For example, a p-value of .01 (p = .01) means there is a 1 in 100 chance the result occurred by chance. The lower the p-value, the more likely it is that the difference between groups was caused by treatment.

p53 gene A tumor suppressor gene that normally inhibits the growth of tumors. This gene is altered in many types of cancer.

Pacific valerian Valeriana officinalis. A plant whose roots are used as a sedative and to treat certain medical conditions. It is being studied as a way to improve sleep in cancer patients undergoing treatment. Also called valerian, garden valerian, Indian valerian, Mexican valerian, garden heliotrope, and Valerianae radix.

pack year A way to measure the amount a person has smoked over a long period of time. It is calculated by multiplying the number of packs of cigarettes smoked per day by the number of years the person has smoked. For example, 1 pack year is equal to smoking 1 pack per day for 1 year, or 2 packs per day for half a year, and so on.

paclitaxel A drug that is used to treat cancer. It belongs to the family of drugs called mitotic inhibitors.

paclitaxel liposome A form of the anticancer drug paclitaxel that may have fewer side effects and work better than paclitaxel. It is being studied in the treatment of cancer. It belongs to the family of drugs called mitotic inhibitors. Also called LEP-ETU and PNU-93914.

Paget's disease of bone A chronic condition in which both the breakdown and regrowth of bone are increased. Paget's disease of bone occurs most frequently in the pelvic and leg bones, skull, and lower spine. It is most common in older individuals, and may lead to bone pain, deformities, and fractures. Also called osteitis deformans.

Paget's disease of the nipple A form of breast cancer in which the tumor grows from ducts beneath the nipple onto the surface of the nipple. Symptoms commonly include itching and burning and an eczema-like condition around the nipple, sometimes accompanied by oozing or bleeding.

pain threshold The point at which a person becomes aware of pain.

PALA A substance that is being studied for its ability to increase the effectiveness of the anticancer drug fluorouracil.

palate (PAL-et) The roof of the mouth. The front portion is bony (hard palate), and the back portion is muscular (soft palate).

palatine uvula The soft flap of tissue that hangs down at the back of the mouth (at the edge of the soft palate). Also called uvula.

palifermin (pal-ee-FER-min) A form of keratinocyte growth factor (KGF) that is made in the laboratory. KGF stimulates the growth of cells that line the surface of the mouth and intestinal tract. Palifermin is used to prevent and treat oral mucositis (mouth sores) caused by high-dose chemotherapy and radiation therapy in leukemia and lymphoma. It is also being studied in the prevention and treatment of oral mucositis (mouth sores) and dysphagia (difficulty swallowing) in other types of cancer. Palifermin belongs to the family of drugs called recombinant human keratinocyte growth factors. Also called Kepivance.

palliative care (PAL-ee-yuh-tiv) Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of palliative care is to prevent or treat as early as possible the symptoms of the disease, side effects caused by treatment of the disease, and psychological, social, and spiritual problems related to the disease or its treatment. Also called comfort care, supportive care, and symptom management.

palliative therapy (PAL-ee-yuh-tiv) Treatment given to relieve the symptoms and reduce the suffering caused by cancer and other life-threatening diseases. Palliative cancer therapies are given together with other cancer treatments, from the time of diagnosis, through treatment, survivorship, recurrent or advanced disease, and at the end of life.

palmar-plantar erythodysthesia A condition marked by pain, swelling, numbness, tingling, or redness of the hands or feet. It sometimes occurs as a side effect of certain anticancer drugs. Also known as hand-foot syndrome.

palpable disease A term used to describe cancer that can be felt by touch, usually present in lymph nodes, skin, or other organs of the body such as the liver or colon.

palpation Examination by pressing on the surface of the body to feel the organs or tissues underneath.

pamidronate A drug that is used to treat hypercalcemia (too much calcium in the blood) and cancer that has spread to the bones. It belongs to the family of drugs called bisphosphonates.

panacea A cure-all.

Pancoast tumor A type of lung cancer that begins in the upper part of a lung and spreads to nearby tissues such as the ribs and vertebrae. Most Pancoast tumors are non-small cell cancers. Also called pulmonary sulcus tumor.

pancreas A glandular organ located in the abdomen. It makes pancreatic juices, which contain enzymes that aid in digestion, and it produces several hormones, including insulin. The pancreas is surrounded by the stomach, intestines, and other organs.

pancreatectomy (pan-kree-a-TEK-toe-mee) Surgery to remove all or part of the pancreas. In a total pancreatectomy, part of the stomach, part of the small intestine, the common bile duct, gallbladder, spleen, and nearby lymph nodes also are removed.

pancreatic Having to do with the pancreas.

pancreatic cancer A disease in which malignant (cancer) cells are found in the tissues of the pancreas. Also called exocrine cancer.

pancreatic duct Part of a system of ducts in the pancreas. Pancreatic juices containing enzymes are released into these ducts and flow into the small intestine.

pancreatic enzyme A protein secreted by the pancreas that aids in the digestion of food.

pancreatic juice Fluid made by the pancreas. Pancreatic juices contain proteins called enzymes that aid in digestion.

pancreatitis Inflammation of the pancreas. Chronic pancreatitis may cause diabetes and problems with digestion. Pain is the primary symptom.

panitumumab A monoclonal antibody that is being studied in the diagnosis and treatment of some types of cancer. Monoclonal antibodies are made in the laboratory and can locate and bind to cancer cells. Also called ABX-EGF.

PAP Prostatic acid phosphatase. An enzyme produced by the prostate. It may be found in increased amounts in men who have prostate cancer.

Pap smear A procedure in which cells are scraped from the cervix for examination under a microscope. It is used to detect cancer and changes that may lead to cancer. A Pap smear can also show noncancerous conditions, such as infection or inflammation. Also called a Pap test.

Pap test A procedure in which cells are scraped from the cervix for examination under a microscope. It is used to detect cancer and changes that may lead to cancer. A Pap test can also show noncancerous conditions, such as infection or inflammation. Also called a Pap smear.

papillary serous carcinoma An aggressive cancer that usually affects the uterus/endometrium, peritoneum, or ovary.

papillary thyroid cancer (PA-pih-LAYR-ee THY-royd KAN-ser) Cancer that forms in cells in the thyroid and grows in small finger-like shapes. It grows slowly, is more common in women than in men, and often occurs before age 40. It is the most common type of thyroid cancer.

papillary tumor (PAP-ih-lar-ee TOO-mer) A tumor shaped like a small mushroom, with its stem attached to the epithelial layer (inner lining) of an organ.

papilledema (pap-il-eh-DEE-ma) Swelling around the optic disk, the area where the optic nerve (the nerve that carries messages from the eye to the brain) enters the eyeball. Papilledema occurs when increased brain pressure caused by tumors or other problems results in swelling of the optic nerve.

paracentesis (PAYR-uh-sen-TEE-siss) A procedure in which a thin needle or tube is put into the abdomen to remove fluid from the peritoneal cavity (the space within the abdomen that contains the intestines, the stomach, and the liver).

paraganglia (PA-ruh-GAN-glee-uh) A collection of cells that came from embryonic nervous tissue, and are found near the adrenal glands and some blood vessels and nerves. Most paraganglia secrete epinephrine and norepinephrine.

paraganglioma (PA-ruh-gan-glee-OE-ma) A rare, usually benign tumor that develops from cells of the paraganglia. Paraganglia are a collection of cells that came from embryonic nervous tissue, and are found near the adrenal glands and some blood vessels and nerves. Paragangliomas that develop in the adrenal gland are called pheochromocytomas. Those that develop outside of the adrenal glands near blood vessels or nerves are called glomus tumors or chemodectomas.

parageusia A bad taste in the mouth. Also called dysgeusia.

paralysis (pa-RAL-ih-sis) Loss of ability to move all or part of the body.

paramyxovirus A type of virus that has hemagglutinin-neuraminidase proteins in the outer coat and RNA as the genetic material. Measles (rubeola) virus, mumps virus, and Newcastle disease virus are paramyxoviruses.

paranasal sinus and nasal cavity cancer (PAYR-uh-NAY-zul SY-nus and NAY-zul KA-vuh-tee KAN-ser) Cancer that forms in tissues of the paranasal sinus (hollow spaces behind the lower part of the forehead, nose, and cheeks, or below the eyes) or nasal cavity (the inside of the nose from the nostrils to the part of the throat between the nose and windpipe). The most common type of this cancer is squamous cell carcinoma (cancer that begins in flat cells lining the paranasal sinus and nasal cavity).

paraneoplastic syndrome (pair-a-nee-o-PLAS-tik) A group of symptoms that may develop when substances released by some cancer cells disrupt the normal function of surrounding cells and tissue.

parasite An animal or plant that gets nutrients by living on or in an organism of another species. A complete parasite gets all of its nutrients from the host organism, but a semi-parasite gets only some of its nutrients from the host.

parasitic (PAYR-uh-SIH-tik) Having to do with or being a parasite (an animal or plant that gets nutrients by living on or in an organism of another species).

parathormone (PA-ruh-THORE-mone) A substance made by the parathyroid gland that helps the body store and use calcium. Also called parathyroid hormone, parathyrin, or PTH.

parathyrin (PA-ruh-THY-rin) A substance made by the parathyroid gland that helps the body store and use calcium. Also called parathormone, parathyroid hormone, or PTH.

parathyroid cancer (PAYR-uh-THY-royd KAN-ser) A rare cancer that forms in tissues of one or more of the parathyroid glands (four pea-sized glands in the neck that make parathyroid hormone, which helps the body store and use calcium).

parathyroid gland (PA-ruh-THY-royd) One of four pea-sized glands found on the thyroid. The parathyroid hormone produced by these glands increases the calcium level in the blood.

parathyroid hormone (PA-ruh-THY-royd HORE-mone) A substance made by the parathyroid gland that helps the body store and use calcium. Also called parathormone, parathyrin, or PTH.

parathyroidectomy (PAYR-uh-THY-roy-DEK-tuh-mee) Surgery to remove one or more parathyroid glands (four pea-sized organs found on the thyroid).

parenchyma (pah-REN-kih-ma) The essential or functional elements of an organ.

parenteral nutrition A form of nutrition that is delivered into a vein. Parenteral nutrition does not use the digestive system. It may be given to people who are unable to absorb nutrients through the intestinal tract because of vomiting that won't stop, severe diarrhea, or intestinal disease. It may also be given to those undergoing high-dose chemotherapy or radiation and bone marrow transplantation. It is possible to give all of the protein, calories, vitamins and minerals a person needs using parenteral nutrition. Also known as hyperalimentation or total parenteral nutrition (TPN).

paresthesias Abnormal touch sensations, such as burning or prickling, that occur without an outside stimulus.

paricalcitol (par-i-KAL-si-tol) A substance that is being used to treat overactive parathyroid glands in patients with kidney failure. It is also being studied in the treatment of cancer. Paricalcitol belongs to the family of drugs called vitamin D analogs.

parietal pericardium The outer layer of the pericardium, which is a thin sac of tissue that surrounds the heart.

parietal peritoneum (puh-RY-uh-tul PAYR-ih-toh-NEE-um) The layers of tissue that line the abdominal wall and the pelvic cavity.

Parkinson's disease A progressive disorder of the nervous system marked by muscle tremors, muscle rigidity, decreased mobility, stooped posture, slow voluntary movements, and a mask-like facial expression.

parotidectomy Surgery to remove all or part of the parotid gland (a large salivary gland located in front of and just below the ear). In a radical parotidectomy, the entire gland is removed.

paroxetine hydrochloride (puh-ROX-uh-teen HY-droh-KLOR-ide) A drug used to treat depression and anxiety disorders. It belongs to the family of drugs called selective serotonin reuptake inhibitors (SSRI). Also called Paxil.

paroxysmal nocturnal hemoglobinuria (puh-rahk-SIZ-mul nok-TUR-nul HEE-moh-gloh-bih-NOO-ree-uh) PNH. A rare disorder in which red blood cells are easily destroyed by certain immune system proteins. Symptoms include blood clots, and red or brownish urine in the morning. Aplastic anemia (decreased production of blood cells) may lead to PNH, and people with PNH are at increased risk of acute myelogenous leukemia.

partial cystectomy (sis-TEK-to-mee) The removal of the cancer as well as some of the bladder tissue around the tumor. Also called segmental cystectomy.

partial hysterectomy (hiss-ter-EK-toe-mee) Surgery to remove the uterus only. When the uterus and part or all of the cervix are removed, it is called a total hysterectomy.

partial laryngectomy (PAR-shul lair-in-JEK-tuh-mee) An operation to remove part of the larynx (voice box).

partial mastectomy (mas-TEK-toe-mee) The removal of cancer as well as some of the breast tissue around the tumor and the lining over the chest muscles below the tumor. Usually some of the lymph nodes under the arm are also taken out. Also called segmental mastectomy.

partial nephrectomy (neh-FREK-tuh-mee) Surgery to remove part of one kidney or a kidney tumor, but not an entire kidney.

partial oophorectomy (o-o-for-EK-toe-mee) Surgery to remove part of one ovary or part of both ovaries.

partial remission A decrease in the size of a tumor, or in the extent of cancer in the body, in response to treatment. Also called partial response.

partial response A decrease in the size of a tumor, or in the extent of cancer in the body, in response to treatment. Also called partial remission.

passive antibody therapy Treatment with injections of antibodies made in another animal or in the laboratory.

Paterson-Kelly syndrome A disorder marked by anemia caused by iron deficiency, and a web-like growth of membranes in the throat that makes swallowing difficult. Having Paterson-Kelly syndrome may increase the risk of developing esophageal cancer. Also called Plummer-Vinson syndrome and sideropenic dysphagia.

pathognomonic (PATH-og-NOH-mah-nik) Having to do with a sign or symptom that is specific to a certain disease.

pathologic fracture A broken bone caused by disease, often by the spread of cancer to the bone.

pathological staging A method used to determine the stage of cancer. Tissue samples are removed during surgery or a biopsy. The stage is determined based on how the cells in the samples look under a microscope.

pathologist (pa-THOL-o-jist) A doctor who identifies diseases by studying cells and tissues under a microscope.

pathology report The description of cells and tissues made by a pathologist based on microscopic evidence, and sometimes used to make a diagnosis of a disease.

patient advocate A person who helps a patient work with others who have an effect on the patient's health, including doctors, insurance companies, employers, case managers, and lawyers. A patient advocate helps resolve issues about health care, medical bills, and job discrimination related to a patient's medical condition. Cancer advocacy groups try to raise public awareness about important cancer issues, such as the need for cancer support services, education, and research. Such groups work to bring about change that will help cancer patients and their families.

patient-controlled analgesia (...AN-ul-JEE-zee-uh) PCA. A method of pain relief in which the patient controls the amount of pain medicine that is used. When pain relief is needed, the person can receive a preset dose of pain medicine by pressing a button on a computerized pump that is connected to a small tube in the body.

Paxil (PAK-sil) A drug used to treat depression and anxiety disorders. It belongs to the family of drugs called selective serotonin reuptake inhibitors (SSRI). Also called paroxetine hydrochloride.

PCA Patient-controlled analgesia. A method in which the patient controls the amount of pain medicine that is used. When pain relief is needed, the person can receive a preset dose of pain medicine by pressing a button on a computerized pump that is connected to a small tube in the body.

PCOS Polycystic ovary syndrome. A condition marked by infertility, enlarged ovaries, menstrual problems, high levels of male hormones, excess hair on the face and body, acne, and obesity. Women with PCOS have an increased risk of diabetes, high blood pressure, heart disease, and endometrial cancer.

PCR Polymerase chain reaction. A laboratory method used to make many copies of a specific DNA sequence.

PDQ Physician Data Query. PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq.

peau d'orange A dimpled condition of the skin of the breast, resembling the skin of an orange, sometimes found in inflammatory breast cancer.

pediatric (pee-dee-AT-rik) Having to do with children.

pediatric hematologist A doctor who specializes in treating blood disorders in children.

pediatric nurse specialist A registered nurse with an advanced degree in nursing who specializes in the care of children.

pediatric surgeon A surgeon who specializes in the treatment of children. A surgeon removes or repairs a part of the body by operating on the patient.

pedigree A record of one's ancestors, offspring, siblings, and their offspring that may be used to determine the pattern of certain genes or disease inheritance within a family.

PEG-interferon alfa-2a (peg-IN-ter-FEER-ahn AL-fa) A drug used to treat hepatitis C infections. It is also being studied in the treatment and prevention of cancer. It is a cytokine that is modified in the laboratory. It belongs to the family of drugs called biological response modifiers. Also called Pegasys.

PEG-interferon alfa-2b (peg IN-ter-FEER-ahn AL-fa) A drug used to treat hepatitis C infections. It is also being studied in the treatment and prevention of cancer. It is a cytokine that is modified in the laboratory. It belongs to the family of drugs called biological response modifiers. Also called PEG-Intron and SCH 54031.

PEG-Intron A drug used to treat hepatitis C infections. It is also being studied in the treatment and prevention of cancer. It is a cytokine that is modified in the laboratory. It belongs to the family of drugs called biological response modifiers. Also called PEG-interferon alfa-2b and SCH 54031.

PEG-MGDF A form of megakaryocyte growth and development factor (MGDF) that is made in the laboratory. MGDF comes from the protein thrombopoietin, which is normally made in the body to help make platelets. PEG-MGDF is being studied as a way to increase the number of platelets in patients receiving chemotherapy. Also called polyethylene glycosylated recombinant human megakaryocyte growth and development factor (PEG-rhMGDF).

PEG-rhMGDF Polyethylene glycosylated recombinant human megakaryocyte growth and development factor. A form of megakaryocyte growth and development factor (MGDF) that is made in the laboratory. MGDF comes from the protein thrombopoietin, which is normally made in the body to help make platelets. PEG-rhMGDF is being studied as a way to increase the number of platelets in patients receiving chemotherapy. Also called PEG-MGDF.

pegaspargase A modified form of asparaginase, an anticancer drug that belongs to the family of drugs derived from enzymes.

Pegasys (PEG-ah-siss) A drug used to treat hepatitis C infections. It is also being studied in the treatment and prevention of cancer. It is a cytokine that is modified in the laboratory. It belongs to the family of drugs called biological response modifiers. Also called PEG-interferon alfa-2a.

pegfilgrastim (peg-FIL-grass-tim) A drug used to increase numbers of white blood cells in patients who are receiving chemotherapy. It belongs to the family of drugs called colony-stimulating factors. Also called Neulasta and filgrastim-SD/01.

PEITC Phenethyl isothiocyanate. A substance that is being studied in the prevention of cancer. It is a naturally occurring compound found in some cruciferous vegetables.

peldesine A substance that is being studied for the treatment of cancer.

pelvic Having to do with the pelvis (the lower part of the abdomen located between the hip bones).

pelvic examination A physical examination in which the health care professional will feel for lumps or changes in the shape of the vagina, cervix, uterus, fallopian tubes, ovaries, and rectum. The health care professional will also use a speculum to open the vagina to look at the cervix and take samples for a PAP test. Also called an internal examination.

pelvic exenteration Surgery to remove the lower colon, rectum, and bladder, and create stomata (openings) through which urine and stool are passed out of the body. In women, the cervix, vagina, ovaries, and nearby lymph nodes are also removed.

pelvic lymphadenectomy (lim-FAD-eh-NEK-tah-me) Surgery to remove lymph nodes in the pelvis for examination under a microscope to see if they contain cancer.

pelvic wall The muscles and ligaments that line the part of the body between the hips.

pelvis The lower part of the abdomen, located between the hip bones.

pemetrexed disodium (pem-eh-TREX-ed dy-SOH-dee-um) A drug that is used to treat malignant pleural mesothelioma and advanced non-small cell lung cancer and is being studied in the treatment of other types of cancer. It belongs to the family of drugs called enzyme inhibitors. Also called Alimta and LY231514.

penclomedine A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called alkylating agents.

penectomy (pee-NEK-toh-mee) Surgery to remove part or all of the penis

penicillamine A drug that removes copper from the body and is used to treat diseases in which there is an excess of copper. It is also being studied as a possible angiogenesis inhibitor in the treatment of brain tumors.

penicillin A drug that is used to treat infection. It belongs to the family of drugs called antibiotics.

penile cancer (PEE-nile KAN-ser) A rare cancer that forms in the penis (the external male reproductive organ). Most penile cancers are squamous cell carcinomas (cancer that begins in flat cells lining the penis).

penile implant A firm rod or inflatable device that is placed in the penis during a surgical procedure. The implant makes it possible to have and keep an erection. Penile implants are used to treat erectile dysfunction or impotence.

penis An external male reproductive organ. It contains a tube called the urethra, which carries semen and urine to the outside of the body.

pentetic acid calcium A drug that protects healthy tissues from the toxic effects of anticancer drugs.

pentosan polysulfate A drug used to relieve pain or discomfort associated with chronic inflammation of the bladder. It is also being evaluated for its protective effects on the gastrointestinal tract in people undergoing radiation therapy.

pentostatin An anticancer drug that belongs to the family of drugs called antimetabolites.

pentoxifylline A drug used to prevent blood clotting and as a treatment that may help decrease weight loss in people with cancer.

peptide Any compound consisting of two or more amino acids, the building blocks of proteins.

peptide 946 A protein that causes white blood cells to recognize and destroy melanoma cells.

percutaneous ethanol injection (per-kyoo-TAY-nee-us) An injection of ethanol (alcohol) through the skin directly into the tumor to kill cancer cells.

percutaneous transhepatic biliary drainage A procedure to drain bile to relieve pressure in the bile ducts caused by a blockage. An x-ray of the liver and bile ducts locates the blockage of bile flow. Images made by ultrasound guide placement of a stent (tube), which remains in the liver. Bile drains through the stent into the small intestine or into a collection bag outside the body. This procedure may relieve jaundice before surgery. Also called percutaneous transhepatic cholangiodrainage (PTCD).

percutaneous transhepatic cholangiodrainage PTCD. A procedure to drain bile to relieve pressure in the bile ducts caused by a blockage. An x-ray of the liver and bile ducts locates the blockage of bile flow. Images made by ultrasound guide placement of a stent (tube), which remains in the liver. Bile drains through the stent into the small intestine or into a collection bag outside the body. This procedure may relieve jaundice before surgery. Also called percutaneous transhepatic biliary drainage.

percutaneous transhepatic cholangiography (per-kyoo-TAY-nee-us trans-heh-PAT-ik ko-LAN-jee-AH-gra-fee) PTC. A procedure to x-ray the hepatic and common bile ducts. A contrasting agent is injected into the liver or bile duct, and the ducts are then x-rayed to find the point of obstruction.

performance status A measure of how well a patient is able to perform ordinary tasks and carry out daily activities.

perfusion Bathing an organ or tissue with a fluid. In regional perfusion, a specific area of the body (usually an arm or a leg) receives high doses of anticancer drugs through a blood vessel. Such a procedure is performed to treat cancer that has not spread.

perfusion magnetic resonance imaging A special type of magnetic resonance imaging (MRI) that uses an injected dye in order to see blood flow through tissues. Also called magnetic resonance perfusion imaging.

pericardial effusion An abnormal collection of fluid inside the sac that covers the heart.

perifosine A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called alkylphospholipids.

perillyl alcohol A substance that is being studied in the prevention of cancer. It belongs to the family of plant drugs called monoterpenes.

perimenopausal The time of a woman's life when menstrual periods become irregular. Refers to the time near menopause.

perineal colostomy An opening made surgically to allow the colon to exit the body through the perineum (the area of the body between the anus and the vulva in females, and between the anus and the scrotum in males). A colostomy provides a new path for waste material to leave the body after part of the colon has been removed.

perineal prostatectomy (peh-rih-NEE-ul prah-stuh-TEK-toh-mee) Surgery to remove the prostate through an incision made between the scrotum and the anus.

perineum The area of the body between the anus and the vulva in females, and between the anus and the scrotum in males.

perineural (pear-ih-NOOR-al) Around a nerve or group of nerves.

perioperative (PER-ee-AH-pruh-tiv) Around the time of surgery. This usually lasts from the time the patient goes into the hospital or doctor's office for surgery until the time the patient goes home.

peripheral blood Blood circulating throughout the body.

peripheral blood lymphocyte therapy A treatment for Epstein-Barr virus infection or overgrowth of white blood cells (lymphocytes) after an organ or bone marrow transplant. Specific lymphocytes from a sibling donor are infused into the patient to try and reverse these conditions.

peripheral blood smear A procedure in which a sample of blood is viewed under a microscope to count different circulating blood cells (red blood cells, white blood cells, platelets, etc.) and see whether the cells look normal.

peripheral neuropathy A condition of the nervous system that causes numbness, tingling, burning or weakness. It usually begins in the hands or feet, and can be caused by certain anticancer drugs.

peripheral primitive neuroectodermal tumor (...NOO-ro-ek-toe-DER-mul...) pPNET. A type of cancer that forms in bone or soft tissue. Also called Ewing's sarcoma.

peripheral stem cell An immature cell found circulating in the bloodstream. New blood cells develop from peripheral stem cells.

peripheral stem cell support (per-IF-er-al) A method of replacing blood-forming cells destroyed by cancer treatment. Immature blood cells (stem cells) in the circulating blood that are similar to those in the bone marrow are given to the patient after treatment. This helps the bone marrow recover and continue producing healthy blood cells. Transplantation may be autologous (an individual's own blood cells saved earlier), allogeneic (blood cells donated by someone else), or syngeneic (blood cells donated by an identical twin). Also called peripheral stem cell transplantation.

peripheral stem cell transplantation (per-IF-er-al) A method of replacing blood-forming cells destroyed by cancer treatment. Immature blood cells (stem cells) in the circulating blood that are similar to those in the bone marrow are given to the patient after treatment. This helps the bone marrow recover and continue producing healthy blood cells. Transplantation may be autologous (an individual's own blood cells saved earlier), allogeneic (blood cells donated by someone else), or syngeneic (blood cells donated by an identical twin). Also called peripheral stem cell support.

peripheral T-cell lymphoma One of a group of aggressive (fast-growing) non-Hodgkin’s lymphomas that begin in mature T lymphocytes (T cells that have matured in the thymus gland and gone to other lymphatic sites in the body, including lymph nodes, bone marrow, and spleen.) Also called mature T-cell lymphoma.

peristalsis (pair-ih-STAL-sis) The rippling motion of muscles in the intestine or other tubular organs characterized by the alternate contraction and relaxation of the muscles that propel the contents onward.

peritoneal (PAYR-ih-toh-NEE-ul) Having to do with the parietal peritoneum (the tissue that lines the abdominal wall and pelvic cavity) and visceral peritoneum (the tissue that covers most of the organs in the abdomen, including the intestines).

peritoneal cancer Cancer of the tissue that lines the abdominal wall and covers organs in the abdomen.

peritoneal cavity The space within the abdomen that contains the intestines, the stomach, and the liver. It is bound by thin membranes.

peritoneal fluid (PAYR-ih-toh-NEE-ul FLOO-id) A liquid that is made in the abdominal cavity to lubricate the surface of the tissue that lines the abdominal wall and pelvic cavity and covers most of the organs in the abdomen.

peritoneal infusion A method of delivering fluids and drugs directly into the abdominal cavity through a thin tube. Also called intraperitoneal infusion.

peritoneal perfusion A method of delivering fluids and drugs directly to tumors in the peritoneal cavity.

peritoneum (PAYR-ih-toh-NEE-um) The tissue that lines the abdominal wall and covers most of the organs in the abdomen.

peritonitis Inflammation of the peritoneum (tissue that lines the abdominal wall and covers most of the organs in the abdomen). Peritonitis can result from infection, injury, or certain diseases. Symptoms may include swelling of the abdomen, severe pain, and weight loss.

pernicious anemia (per-NISH-us a-NEE-mee-a) A type of anemia (low red blood cell count) caused by the body's inability to absorb vitamin B12.

perturbation A disruption or disturbance.

pertuzumab (per-TOO-zoo-mab) A monoclonal antibody that is being studied in the treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

pesticide (PES-tih-side) A chemical that is used to kill insects and other pests.

PET scan Positron emission tomography scan. A procedure in which a small amount of radioactive glucose (sugar) is injected into a vein, and a scanner is used to make detailed, computerized pictures of areas inside the body where the glucose is used. Because cancer cells often use more glucose than normal cells, the pictures can be used to find cancer cells in the body.

petechiae (peh-TEH-kee-a) Pinpoint, unraised, round red spots under the skin caused by bleeding.

Peutz-Jeghers syndrome PJS. A genetic disorder in which polyps form in the intestine and dark spots appear on the mouth and fingers. Having PJS increases the risk of developing gastrointestinal and many other types of cancer.

phagocyte An immune system cell that can surround and kill microorganisms and remove dead cells. Phagocytes include macrophages.

phantom limb pain The sensation of pain or other unpleasant feelings in the place of a missing (phantom) limb.

pharmacokinetics The activity of drugs in the body over a period of time, including the processes by which drugs are absorbed, distributed in the body, localized in the tissues, and excreted.

pharmacopoeia A 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 the windpipe and esophagus). Pharyngeal cancer includes cancer of the nasopharynx (the upper part of the throat behind the nose), the oropharynx (the middle part of the pharynx), and the hypopharynx (the bottom part of the pharynx). Most pharyngeal cancers are squamous cell carcinomas (cancer that begins in flat cells lining the pharynx). Also called throat cancer.

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 the stomach). The pharynx is about 5 inches long, depending on body size. Also called the throat.

phase I detoxification A 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 that is easier for the body to excrete.

phase I trial The 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, or injection) and the best dose. The dose is usually increased a little at a time in order to find the highest dose that does not cause harmful side effects. Because little is known about the possible risks and benefits of the treatments being tested, phase I trials usually include only a small number of patients who have not been helped by other treatments.

phase I/II trial A trial to study the safety, dosage levels, and response to a new treatment.

phase II detoxification A 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 that is easier for the body to excrete. In phase II detoxification, liver cells add a substance (such as cysteine, glycine, or a sulfur molecule) to a toxic chemical or drug, to make it less harmful.

phase II trial A 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 works against a certain type of cancer.

phase II/III trial A trial to study response to a new treatment and the effectiveness of the treatment compared with the standard treatment regimen.

phase III trial A 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 better survival rates or fewer side effects). In most cases, studies move into phase III only after a treatment seems to work in phases I and II. Phase III trials may include hundreds of people.

phase IV trial After 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 III trial. Thousands of people are involved in a phase IV trial.

phenethyl isothiocyanate PEITC. A substance that is being studied in the prevention of cancer. It is a naturally occurring compound found in some cruciferous vegetables.

phenobarbital A 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 effect of other therapies. It belongs to the family of drugs called barbiturates.

phenoxodiol A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called signal transduction inhibitors.

phenylacetate A substance that is being studied in the treatment of cancer.

phenylbutyrate A 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) PKU. An inherited disorder that causes a build-up of phenylalanine (an amino acid) in the blood. This can cause mental retardation, behavioral and movement problems, seizures, and delayed development. Using a blood test, PKU can easily be found in newborns, and treatment is a diet low in phenylalanine.

pheochromocytoma A tumor of the adrenal gland that causes it to produce too much adrenaline. Pheochromocytomas are usually benign (noncancerous), but can cause dangerously high blood pressure and other symptoms, including pounding headaches, heart palpitations, flushing of the face, nausea, and vomiting.

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 returned to the donor. Also called apheresis.

Philadelphia chromosome An abnormality of chromosome 22 in which part of chromosome 9 is transferred to it. Bone marrow cells that contain the Philadelphia chromosome are often found in chronic myelogenous leukemia.

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.

phlebotomy The puncture of a vein with a needle for the purpose of drawing blood. Also called venipuncture.

phospholipid A lipid (fat) that contains phosphorus. Phospholipids are a major part of cell membranes.

phospholipid complex A chemical or drug that is attached to a lipid (fat) that contains phosphorus.

phosphorous (FOS-for-us) 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 primary energy source for the body's cells).

phosphorus-32 A radioactive form of phosphorus used in the treatment of cancer. It is also used to help locate areas of DNA damage.

photoactivity The 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 kill tumor cells.

photodynamic therapy (foe-toe-dye-NAM-ik) Treatment with drugs that become active when exposed to light. These drugs 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, porfimer sodium becomes active and kills the cancer cells. It belongs to the family of drugs called photodynamic therapy agents. Also called porfimer sodium.

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 light. The blood is then returned to the body. It is being studied in the treatment of some blood and bone marrow diseases and graft-vs-host disease (GVHD). Also called extracorporeal photopheresis.

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 cancer cells. Also called photosensitizing agent.

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 the cancer cells. Also called photosensitizer.

phyllodes tumor A type of tumor found in breast tissue. It is often large and bulky and grows quickly. It is usually benign (not cancer), but may be malignant (cancer). Also called cystosarcoma phyllodes.

physical examination An exam of the body to check for general signs of disease.

physical therapist A health professional who teaches exercises and physical activities that help condition muscles and restore strength and movement.

physical therapy The use of exercises and physical activities to help condition muscles and restore strength and movement. For example, physical therapy can be used to restore arm and shoulder movement and build back strength after breast cancer surgery.

physician Medical doctor.

Physician Data Query PDQ. The Physician Data Query is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq.

physiologic Having to do with the functions of the body. When used in the phrase "physiologic age," it refers to an age assigned by general health, as opposed to calendar age.

phytic acid (FY-tik ASS-id) A substance found in many foods that come from plants, including corn, wheat, rice, and soybeans, and in large amounts in cereals and legumes. It is being studied in the prevention of cancer. Also called inositol hexaphosphate (IP6).

phytochemical (FY-toh-KEH-mih-kuhl) A substance found in plants. Some phytochemicals may reduce the risk of cancer.

phytoestrogen An estrogen-like substance found in some plants and plant products. Phytoestrogens may have anticancer effects.

phytosterol A plant-based compound that can compete with dietary cholesterol to be absorbed by the intestines, resulting in lower blood cholesterol levels. Phytosterols may have some effect in cancer prevention. Also called plant sterol.

PI-88 A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antiangiogenesis agents.

pigment A substance that gives color to tissue. Pigments are responsible for the color of skin, eyes, and hair.

pilocarpine A drug used to increase salivation in people who have dry mouth caused by opioids or radiation therapy. Pilocarpine belongs to the family of drugs called alkaloids.

pilocytic (PI-lo-SIT-ik) Made up of cells that look like fibers when viewed under a microscope.

pilot study The initial study examining a new method or treatment.

PIN Prostatic intraepithelial neoplasia. Noncancerous growth of cells lining the internal and external surfaces of the prostate gland. Having high-grade PIN may increase the risk of developing prostate cancer.

pineal body A tiny organ in the cerebrum that produces melatonin. Also called pineal gland or pineal organ.

pineal gland (PIN-ee-al) A tiny organ in the cerebrum that produces melatonin. Also called pineal body or pineal organ.

pineal organ A tiny organ in the cerebrum that produces melatonin. Also called pineal body or 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-o-blas-TOE-ma) 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-o-sye-TOE-ma) A slow growing type of brain tumor that occurs in or around the pineal gland, a tiny organ near the center of the brain.

pinkeye A condition in which the conjunctiva (membranes lining the eyelids and covering the white part of the eye) become inflamed or infected. Also called conjunctivitis.

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. It may be able to stop leukoplakia (a precancerous condition affecting the mouth) from developing into cancer. It belongs to the family of drugs called thiazolidinediones. Also called Actos.

piperacillin-tazobactam A drug combination that is used to treat infection in people with cancer. Piperacillin is a synthetic penicillin; tazobactam enhances the effectiveness of piperacillin.

pirfenidone A substance that is being studied in the prevention and treatment of scar tissue caused by radiation therapy. It belongs to the family of drugs called anti-inflammatory agents.

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-tair-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 the nose. It makes hormones that affect other glands and many body functions, especially growth. Most pituitary tumors are benign (not cancer).

pixantrone A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antitumor antibiotics. Also called BBR 2778.

PJS Peutz-Jeghers syndrome. A genetic disorder in which polyps form in the intestine and dark spots appear on the mouth and fingers. Having PJS increases the risk of developing gastrointestinal and many other types of cancer.

PKC Protein kinase C. An enzyme found throughout the body's tissues and organs. Several forms of PKC are involved in many cellular functions. PKC is being studied in the treatment of cancer.

PKC412 A substance that is being studied in the treatment of cancer. It belongs to the families of drugs called protein kinase C (PKC) and protein tyrosine kinase inhibitors.

PKU Phenylketonuria . An inherited disorder that causes a build-up of phenylalanine (an amino acid) in the blood. This can cause mental retardation, behavioral and movement problems, seizures, and delayed development. Using a blood test, PKU can easily be found in newborns, and treatment is a diet low in phenylalanine.

placebo An inactive substance or treatment that looks the same as, and is given the same way as, an active drug or treatment being tested. The effects of the active drug or treatment are compared to the effects of the placebo.

placebo-controlled Refers to a clinical study in which the control patients receive a placebo.

placenta The organ that nourishes the developing fetus in the uterus.

placental blood transplantation The transfer of blood from a placenta to an individual whose own blood production system is suppressed. Placental blood contains high levels of stem cells needed to produce new blood cells. It is being studied in the treatment of cancer and severe blood disorders such as aplastic anemia. Also called umbilical cord blood transplant.

plant sterol A plant-based compound that can compete with dietary cholesterol to be absorbed by the intestines, resulting in lower blood cholesterol levels. Plant sterols may have some effect in cancer prevention. Also called phytosterol.

plaque In medicine, a small, abnormal patch of tissue on a body part or an organ. Plaques may also be a build-up of substances from a fluid, such as cholesterol in the blood vessels.

plasma (PLAS-ma) The clear, yellowish, fluid part of the blood that carries the blood cells. The proteins that form blood clots are in plasma.

plasma cell A type of white blood cell that produces antibodies.

plasma cell myeloma A type of cancer that begins in plasma cells (white blood cells that produce antibodies). Also called multiple myeloma, Kahler’s disease, or myelomatosis.

plasma cell tumor A tumor that begins in plasma cells (white blood cells that produce antibodies). Multiple myeloma, monoclonal gammopathy of undetermined significance (MGUS), and plasmacytoma are types of plasma cell tumors.

plasma membrane The outer membrane of a cell.

plasmacytic Having to do with plasma cells (a type of white blood cells).

plasmacytoma (PLAZ-ma-sye-TOE-ma) A type of cancer that begins in plasma cells (white blood cells that produce antibodies). A plasmacytoma may turn into multiple myeloma.

plasmapheresis (plas-ma-fer-EE-sis) The process of separating certain cells from the plasma in the blood by a machine; only the cells are returned to the person. Plasmapheresis can be used to remove excess antibodies from the blood.

plastic surgeon A surgeon who specializes in reducing scarring or disfigurement that may occur as a result of accidents, birth defects, or treatment for diseases.

plastic surgery An operation that restores or improves the appearance of body structures.

platelet (PLATE-let) A type of blood cell that helps prevent bleeding by causing blood clots to form. Also called a thrombocyte.

platinum A metal that is an important component of some anticancer drugs, such as cisplatin and carboplatin.

Plenaxis A drug used to reduce the amount of testosterone made in patients with advanced symptomatic prostate cancer for which no other treatment options are available. It belongs to the family of drugs called gonadotropin-releasing hormone (GnRH) antagonists. Also called abarelix.

pleomorphic Occurring in various distinct forms. In terms of cells, having variation in the size and shape of cells or their nuclei.

pleura (PLOOR-a) A thin layer of tissue covering the lungs and lining the interior wall of the chest cavity. It protects and cushions the lungs. This tissue secretes a small amount of fluid that acts as a lubricant, allowing the lungs to move smoothly in the chest cavity while breathing.

pleural cavity The space enclosed by the pleura, which is a thin layer of tissue that covers the lungs and lines the interior wall of the chest cavity.

pleural effusion An abnormal collection of fluid between the thin layers of tissue (pleura) lining the lung and the wall of the chest cavity.

pleurodesis (PLOO-ro-DEE-sis) A medical procedure that uses chemicals or drugs to cause inflammation and adhesion between the layers of the pleura (the tissue that covers the lungs and lines the interior wall of the chest cavity). This prevents the buildup of fluid in the pleural cavity. It is used as a treatment for severe pleural effusion.

pleuropulmonary blastoma (ploor-oh-PUL-moh-nayr-ee blas-TOH-muh) A rare and very aggressive (fast-growing) cancer that forms in tissues of the lung and pleura (a thin layer of tissue covering the lungs and the inside wall of the chest cavity). Pleuropulmonary blastoma is most common in children.

plexiform neurofibroma A nerve that has become thick and misshapen due to the abnormal growth of cells and tissues that cover the nerve.

plexopathy (pleks-AH-pah-thee) A disorder affecting a network of nerves, blood vessels, or lymph vessels.

PLL Prolymphocytic leukemia. A type of chronic lymphocytic leukemia (CLL) in which too many immature white blood cells (prolymphocytes) are found in the blood and bone marrow. PLL usually progresses more rapidly than classic CLL.

ploidy (PLOY-dee) The number of sets of chromosomes in a cell or an organism. For example, haploid means one set and diploid means two sets.

Plummer-Vinson syndrome A disorder marked by anemia caused by iron deficiency, and a web-like growth of membranes in the throat that makes swallowing difficult. Having Plummer-Vinson syndrome may increase the risk of developing esophageal cancer. Also called Paterson-Kelly syndrome and sideropenic dysphagia.

pluripotent Able to mature or develop in any of several ways.

pluripotent stem cell A cell that is able to develop into several different types of cells or tissues in the body.

pM-81 A monoclonal antibody that is being studied in the detection and treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

PN401 A substance that is being studied for its ability to protect against thet Able to mature or develop in any of several ways.

pluripotent stem cell A cell that is able to develop into several different types of cells or tissues in the body.

pM-81 A monoclonal antibody that is being studied in the detection and treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

PN401 A substance that is being studied for its ability to protect against thet Able to mature or develop in any of several ways.

pluripotent stem cell A cell that is able to develop into several different types of cells or tissues in the body.

pM-81 A monoclonal antibody that is being studied in the detection and treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

PN401 A substance that is being studied for its ability to protect against thet Able to mature or develop in any of several ways.

pluripotent stem cell A cell that is able to develop into several different types of cells or tissues in the body.

pM-81 A monoclonal antibody that is being studied in the detection and treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

PN401 A substance that is being studied for its ability to protect against thet Able to mature or develop in any of several ways.

pluripotent stem cell A cell that is able to develop into several different types of cells or tissues in the body.

pM-81 A monoclonal antibody that is being studied in the detection and treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

PN401 A substance that is being studied for its ability to protect against thet Able to mature or develop in any of several ways.

pluripotent stem cell A cell that is able to develop into several different types of cells or tissues in the body.

pM-81 A monoclonal antibody that is being studied in the detection and treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

PN401 A substance that is being studied for its ability to protect against thet Able to mature or develop in any of several ways.

pluripotent stem cell A cell that is able to develop into several different types of cells or tissues in the body.

pM-81 A monoclonal antibody that is being studied in the detection and treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

PN401 A substance that is being studied for its ability to protect against thet Able to mature or develop in any of several ways.

pluripotent stem cell A cell that is able to develop into several different types of cells or tissues in the body.

pM-81 A monoclonal antibody that is being studied in the detection and treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

PN401 A substance that is being studied for its ability to protect against thet Able to mature or develop in any of several ways.

pluripotent stem cell A cell that is able to develop into several different types of cells or tissues in the body.

pM-81 A monoclonal antibody that is being studied in the detection and treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

PN401 A substance that is being studied for its ability to protect against thet Able to mature or develop in any of several ways.

pluripotent stem cell A cell that is able to develop into several different types of cells or tissues in the body.

pM-81 A monoclonal antibody that is being studied in the detection and treatment of cancer. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.