p27: a protein that helps to regulate cell growth and a loss of p27 expression is associated with poor prognosis in prostate cancer
p53: a protein that detects and repairs gene damage, coordinating events that cause the cell to stop its growth and repair the damage. If the damage is too great, p53 becomes the catalyst directing the damaged cell to commit suicide.
PAACT: Patient Advocates for Advanced Cancer Treatment – www.paactusa.org
paclitaxel (Taxol®): one of the chemotherapy agents called taxanes that block cell division
Palladium-103: radioactive source used for brachytherapy. Pd-103 gives off energy more quickly than iodine. The radioactive half-life of palladium is 17 days.
palliative: designed to relieve a particular problem without necessarily solving it; for example, palliative therapy is given in order to relieve symptoms and improve quality of life, but does not cure the patient
palpable: capable of being felt during a physical examination by an experienced physician; in the case of prostate cancer, this normally refers to some form of abnormality of the prostate which can be felt during a digital rectal examination
palpation: physical examination in medical diagnosis by pressure of the hand or fingers to the surface of the body especially to determine the condition (as of size or consistency) of an underlying part or organ
pamidronate: a disodium bisphosphonate bone-resorption inhibitor C3H9NNa2O7P2 administered as an intravenous infusion in the treatment of hypercalcemia associated with malignancy called also pamidronate disodium
PAP (prostatic acid phosphatase): an enzyme or biomarker secreted by prostate cells associated with a higher probability of disease outside the prostate when levels are 3.0 or higher; PAP elevations suggest that the disease is not OCD (organ confined disease)
papaverine: a drug which causes blood vessels to expand, thereby increasing blood flow; when papaverine is injected into the penis, it produces an erection by increasing blood flow to the penis; see also phentolamine, “bimix”, “trimix”
paracrine: a form of signaling in which the target cell is close to the signal-releasing cell; compare to endocrine.
parathyroid hormone (PTH): one of the principal calcium-regulating hormones in the body
partial response (PR): a 50% or greater decline in parameters that are being used to measure anti-cancer activity; parameters include abnormalities involving physical exam findings, lab and radiologic studies; also see complete response (CR)
partial voluming: the presence of different tissue types (e.g. healthy and malignant) within a spectroscopic volume leading to an averaging of the resulting spectra – a loss of resolution due to excessively large voxels, typically caused by scan slices that are too thick
Partin tables: tables constructed based on results of the PSA, clinical stage and Gleason score involving thousands of men with PC; used to predict the probability that the prostate cancer has spread to the lymph nodes, seminal vesicles, penetrated the capsule or that it remains confined to the prostate; developed by a group of scientists at the Brady Institute for Urology at Johns Hopkins University. Related Paper
PC-3: human PC cell line that is androgen independent
PCRI: The Prostate Cancer Research Institute; a non-profit organization located in Los Angeles whose goal is to educate patients and physicians about PC; telephone number is 310-743-2116; Web site: www.pcri.org
pelvic lymph node dissection: removal of lymph nodes in the area of the pelvis to check for presence of cancer
peptide: a compound of two or more amino acids where the alpha carboxyl group of one is bound to the alpha amino group of another
perfluorocarbon liquid: a colorless and odorless liquid in which all hydrogen atoms have been replaced by fluorine atoms. This liquid is injected within the MEDRAD endorectal coil instead of air to increase image and spectral quality.
peripheral zone: the largest portion of the prostate located in the back closest to the rectum
perirectal: the tissues surrounding the rectum
phagocytosis: the engulfing and ingesting of a substance within a cell; e.g. a macrophage may phagocytize bacteria or other cells
phase I, II or III clinical trial: see Clinical Trial
phentolamine: given by injection causes blood vessels to expand, thereby increasing blood flow; when injected into the penis, it increases blood flow to the penis, which results in an erection. see also papaverine, “bimix”, “trimix”
phosphorylation: the addition of phosphate to an organic compound through the action of a phosphorylase or kinase
photon: A unit of energy of a light ray or other form of radiant energy. Most conventional radiation uses photons to deliver ionizing radiation.
PICP: carboxy-terminal propeptide of type 1 procollagen; a bone formation marker
PIN: prostatic intraepithelial (or intraductal) neoplasia; a pathologically identifiable condition characterized by microscopic changes in the epithelial cells; also known more simply as dysplasia by many physicians; broken down into high-grade PIN or PIN 2 and PIN 3 or low-grade PIN or PIN 1. High grade PIN is what is believed to be a precursor to PC
planning target volume (PTV): Equivalent to the clinical target volume plus a margin to account for uncertainty in immobilization and localization of the patient anatomy during treatment
plasma: The clear, yellowish fluid portion of blood, lymph, or intramuscular fluid in which cells are suspended. It differs from serum in that it contains fibrin and other soluble clotting elements.
platelet: a particle found in the bloodstream that binds at the site of a wound to begin the blood clotting process; platelets are formed in bone marrow.
plexus: a structure in the form of a network, especially of nerves, blood vessels, or lymphatics
PNI: perineural invasion
polymerase chain reaction (PCR): system for in vitro amplification of DNA that involves separating the DNA into its two complementary strands and using DNA enzymes to synthesize two-stranded DNA from each single strand, and repeating the process
positive: the term used to describe a test result which shows the presence of the substance or material for which the test was carried out; for example, a positive bone scan would show signs of bone metastases
positive margin: the pathologic finding of cancer cells on the outer edge of the tissue removed
PR (progesterone receptor): the docking site on a cell that interacts with progestins
prednisone (Orasone® or Deltasone® or Liquid Pred® or Meticorten®): a glucocorticoid steroid used to treat anorexia and cachexia and some cancers. It is similar to a steroid hormone made by the adrenal glands in the body.
priapism: an abnormal, painful erection where the penis remains erect for an extended period of time that is usually not accompanied with sexual desire
Procrit®: a recombinant human erythropoietin used to treat anemia
prognosis: the patient's potential clinical outlook based on the status and probable course of his disease; chance of recovery
Proscar®: brand name of finasteride; a 5 AR inhibitor
prospective: relating to or being a study (as of the incidence of disease) that starts with the present condition of a population of individuals and follows them into the future — compare retrospective
prostaglandin: hormone like substances that stimulate target cells into action; they differ from hormones in that they act locally, near their site of synthesis, and they are metabolized very rapidly; any of various oxygenated unsaturated cyclic fatty acids of animals that have a variety of hormone like actions (as in controlling blood pressure or smooth muscle contraction)
prostate specific antigen (PSA): a protein secreted by the epithelial cells of the prostate gland including cancer cells; an elevated level in the blood indicates an abnormal condition of the prostate gland, either benign or malignant; it is used to detect potential problems in the prostate gland and to follow the progress of PC therapy (see screening)
prostate-specific membrane antigen (PSMA): a biomarker of prostate epithelial cell activity that is expressed in the membrane of prostate epithelial cells. PSMA is composed of a short 19 amino acid intra-cellular domain, a 24 amino acid transmembrane domain and a 707 amino acid extra-cellular domain. PSMA antigen is radiologically identified (imaged) using a monoclonal antibody attached to a radioactive Indium 111 isotope (ProstaScint scan) to allow visualization of PSMA antigen-containing tissue found within lymph nodes and/or prostate gland.
prostatic acid phosphatase (PAP): an enzyme or biomarker secreted by prostate cells associated with a higher probability of disease outside the prostate when levels are 3.0 or higher; PAP elevations suggest that the disease is not OCD (organ confined disease)
prostatitis: infection or inflammation of the prostate gland treatable by medication and/or manipulation; (BPH is a more permanent laying down of fibrous and connective tissue caused when the prostate tries to contain a relatively silent chronic lower-grade infection, often requiring a TURP to relieve the symptoms)
protease inhibitor: a substance that inhibits the action of a protease
protein: any of a group of complex organic macromolecules that contain carbon, hydrogen, oxygen, nitrogen, and usually sulfur and are composed of one or more chains of amino acids. Proteins are fundamental components of all living cells and include many substances, such as enzymes, hormones, and antibodies, that are necessary for the proper functioning of an organism. They are essential in the diet of animals for the growth and repair of tissue and can be obtained from foods such as meat, fish, eggs, milk, and legumes
proton beam radiation therapy: a form of RT that uses the proton, a positively charged nuclear particle, to deliver ionizing radiation. The proton can be programmed to stop at a particular depth within tissue for the delivery of its radiation payload
proximal: a part of the body that is nearer to the point of reference, compare to distal
PSA: see prostate-specific antigen.
PSA density (PSAD): The amount of PSA per unit volume of the prostate gland; the quotient of PSA divided by gland volume; a reflection of tumor density within the prostate
PSA doubling time (PSADT): the calculation of the time it takes for the PSA value to double based on at least three values separated by at least three months each; before diagnosis, a PSADT of less than 10 years may be an indication of the presence of PC
PSA II: see free PSA.
PSA nadir (PSAN): the lowest value the PSA reaches during or after a particular treatment; a progressive rise after a PSA nadir has been reached usually indicates biologic activity of PC
PSA relapse-free survival: survival of the PC patient that relates to no evidence of biochemical relapse based on a rising PSA as seen in 3 consecutive determinations; also called biochemical relapse-free survival ( bRFS)
PSA response: normally referred to as a decline in PSA of > 50%
PSA slope: the rate of rise in the PSA level normally expressed as ng/mL per month
PSA velocity (PSAV): the calculation of the rate of increase in PSA levels in succeeding PSA tests; before diagnosis, a PSAV of 0.75 ng/ml/year (or higher) may be an indication of the presence of PC
psychogenic: produced or caused by psychological or mental factors rather than organic factors; compare to neurogenic
Pub Med: a Web site which allows access to thousands of published medical studies. It is a service of the National Institute of Health and can be found at www.pubmed.com
pubic arch: the arch formed by the inferior rami of the pubic bones
pubo-prostatic: relating to the structures/supports which connects the capsule of the prostate gland to symphysis pubis
qCT: quantitative CT bone densitometry; an alternate way to evaluate bone density besides the DEXA scan; qCT is not falsely elevated due to calcium deposits in blood vessels or due to degenerative joint disease