Glossary I

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IAD (intermittent androgen deprivation): ADT that discontinues testosterone lowering therapy with the intent to allow the patient to recover from symptoms of ADS as testosterone levels recover to normal; same as IHT or IAS. See our paper Intermittent Androgen Deprivation

IAS: intermittent androgen suppression; same as IAD, IHT

ICTP: carboxy-terminal telopeptide of type 1 collagen (a bone resorption marker like Dpd)

IGF-1: Insulin growth factor 1

IGFBP: Insulin growth factor binding protein; e.g. IGFBP3

IGRTIGRT: a procedure that uses a computer to create a picture of a tumor to help guide the radiation beam during radiation therapy. The pictures are made using CT, ultrasound, X-ray, or other imaging techniques. IGRT makes radiation therapy more accurate and causes less damage to healthy tissue. Also called image-guided radiation therapy. (source:

IHT: intermittent hormone therapy; see IAD

IL-1(interleukin-1): a cell product involved in the immune response (cytokine) which facilitates osteoblast growth among its many functions; see issue 2 of Insights for a more detailed description with illustrations

IL-1R: Interleukin 1 receptor

IL-6 (interleukin-6): a cytokine that stimulates osteoclast precursors and mature osteoclasts among its many functions; see issue 2 of Insights for a more detailed description with illustrations

imaging: a radiology technique or method allowing a physician to see a graphic representation of something that would not normally be visible

immortalization: the ability of a genetically engineered cell line to reproduce indefinitely

Immulite®: laboratory console manufactured by Diagnostics Products Company (DPC) that evaluates biomarkers such as ultrasensitive PSA

immune reaction: a bodily defense reaction that recognizes an invading substance (an antigen: such as a virus or fungus or bacteria or transplanted organ) and produces antibodies specific against that antigen

immune system: the biological system which protects a person or animal from the effects of foreign materials such as bacteria, viruses, cancer cells, and other things which might make that person or animal sick

immunoassay: a laboratory technique that makes use of the binding between an antigen and its homologous antibody in order to identify and quantify the specific antigen or antibody in a sample

immunoblot: a blot in which a radiolabeled antibody is used as the molecular probe

immunodeficient: the ability of a body’s immune system to fight disease is compromised or absent

immunogenic: capable of inducing a strong immune response

immunohistochemistry: of or relating to the application of tissue chemistry and immune reaction methods to analysis of living cells and tissues

immunoperoxidase: stains which are used in the microscopic examination of tissues. These stains are based on antibodies which will bind to specific antigens, usually of protein or glycoprotein origin

immunopositive: a positive result is observed on immunostaining for the target substance

immunoreaction, immunoreactivity: See immune reaction.

immunostaining: the staining of a specific substance by using an antibody against it which is complexed (formed into a complex) with a staining medium

immunotherapy: treatment of disease by inducing, enhancing, or suppressing an immune system response.

implant: a device that is inserted into the body; e.g., a tiny container of radioactive material inserted in or near a tumor (see brachytherapy); also a device inserted in order to replace or substitute for an ability which has been lost; for example, a penile implant is a device which can be surgically inserted into the penis to provide rigidity for intercourse

impotence: the inability to have or to maintain an erection satisfactory for intercourse; also known as ED or erectile dysfunction

IMRT (intensity modulated radiation therapy): an approach to radiation therapy allowing the treatment team to specify the tumor target dose and the amount of radiation allowable to the nearby tissues and uses sophisticated computer planning to arrive at acceptable equations; sophisticated hardware is also incorporated into this planning that allows the radiation intensity to be modulated up or down as the delivery system rotates around the patient – see our paper Targeting For Cure: Intensity Modulated Radiation Therapy

incidental: insignificant or irrelevant; for example, incidental prostate cancer (also known as latent prostate cancer) is a form of prostate cancer which is of no clinical significance to the patient in whom it is discovered

incontinence: (urinary incontinence) loss of urinary control; there are various kinds and degrees of incontinence; overflow incontinence is a condition in which the bladder retains urine after voiding; as a consequence, the bladder remains full most of the time, resulting in involuntary seepage of urine from the bladder; stress incontinence is the involuntary discharge of urine when there is increased pressure upon the bladder, as in coughing or straining to lift  heavy objects; total incontinence is the inability to voluntarily exercise control over the sphincters of the bladder neck and urethra, resulting in total loss of retentive ability – see our paper Incontinence Treatment Options for Post-Prostatectomy

indication: a reason for doing something or taking some action; also used to mean the approved clinical application of a pharmaceutical

indolent: minimal disease, defined as < 0.5 cc of cancer confined to the prostate with no Gleason grade 4 or 5

induration: an increase in the fibrous elements in tissue, a hardened mass or formation, which if felt during a DRE is worrisome

infiltrate (adj. infiltrative): to penetrate through a porous tissue

inflammation: any form of swelling or pain or irritation

informed consent: permission to proceed given by a patient after being fully informed of the purposes and potential consequences of a medical procedure

innervate: to supply a body part with nerves

in situ: in the natural or usual place

Insights: the newsletter of the Prostate Cancer Research Institute (PCRI Insights)

insulin: hormone that helps the body use glucose (sugar) for energy

insulin growth factor1 (IGF-1): a growth factor that stimulates PC cell growth and osteoblast growth

intensity map: representations of energy deposited per unit volume across a treatment volume when the deposition of energy is not delivered in a homogeneous manner

interferon: a body protein that affects antibody production and can modulate (regulate) the immune system

interleukin (IL): any of various compounds of low molecular weight that are produced by T-cells and macrophages and that function especially in regulation of the immune system and cell-mediated immunity

interstitial: within a particular organ; for example, interstitial prostate radiation therapy is radiation therapy applied within the prostate using implanted radioactive pellets or seeds (see also brachytherapy)

intracrinology: the part of endocrinology that focuses on the fact that, in men and women, an important proportion of androgens and estrogens are synthesized locally at their site of action in peripheral target tissues

intraductal: within a duct

intraepithelial: within the layer of cells that forms the surface or lining of an organ

intraglandular prostate cancer: See organ confined disease (OCD).

intraoperative: occurring, carried out, or encountered in the course of surgery

intravascular: within a vessel or vessels

intravenous (IV): into a vein

invasive: requiring an incision or the insertion of an instrument or substance into the body

inverse planningTreatment planning for radiation therapy in which various aspects of the treatment plan are generated by a computer in order to achieve the dose distribution prescribed by a physician

investigational: a drug or procedure allowed by the FDA for use in clinical trials

in vitro: in an artificial environment e.g. within a Petri dish or test-tube

in vivo: within a living organism

involution: a normal process marked by decreasing size of an organ

Iodine-125: radioactive source used for brachytherapy. I=125 gives off energy at a slow and continuous rate. The half life of iodine is 60 days.

ion: atom or molecule that has acquired an electric charge by the loss or gain of one or more electrons

ipsilateral: pertaining to, situated on, or affecting the same side of the body

IPSS: (international prostate symptom score) –see AUA Symptom Score

ionize: to dissociate atoms or molecules into electrically charged atoms or radicals

Iressa®: the trade name for gefitinib

isocenter: The center of rotation of a treatment arc/p>

isodose contour: A two or three-dimensional shape that contains the volume receiving a dose greater than or equal to a specified amount

isodose line: A two-dimensional line that circumscribes an area receiving a dose greater than or equal to a specified amount

isoform: One of a set of similar proteins that have the same function but slightly different composition, e.g. free and complexed PSA

isotherm: a line on a chart representing the locations of zones having a particular temperature

isotope: a different form of a chemical element having similar properties

iterations: Repeated series of steps, performed either by the computer or by the user, implemented to develop a treatment plan

IVP (intravenous pyelogram): a procedure that introduces an X-ray absorbing dye into the urinary tract in order to allow the physician a superior image of the tract by taking an x-ray;