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Prostate-specific antigen (PSA), also known as gamma-seminoprotein or kallikrein-3 (KLK3), is a glycoprotein enzyme encoded in humans by the KLK3 gene. PSA is a member of the kallikrein-related peptidase family and is secreted by the epithelial cells of the prostate gland. PSA is produced for the ejaculate, where it liquefies semen in the seminal coagulum and allows sperm to swim freely. It is also believed to be instrumental in dissolving cervical mucus, allowing the entry of sperm into the uterus.
A rectal examination or rectal exam is an internal examination of the rectum such as by a physician or other healthcare professional.
The digital rectal examination (DRE, Latin palpatio per anum or PPA) is a relatively simple procedure. The patient undresses, then is placed in a position where the anus is accessible (lying on the side, squatting on the examination table, bent over the examination table, or lying down with feet in stirrups).
Prostate cancer screening is an attempt to identify individuals with prostate cancer in a broad segment of the population—those for whom there is no reason to suspect prostate cancer. There are currently[update] two methods used: One is the digital rectal examination (DRE), in which the examiner inserts a gloved, lubricated finger into the rectum to examine the adjoining prostate. The other is the prostate-specific antigen (PSA) blood test, which measures the concentration of this molecule in the blood.
The United States Preventive Services Task Force (USPSTF) recommended against PSA screening in healthy men finding that the potential risks outweigh the potential benefits. Guidelines from the American Urological Association, and the American Cancer Society recommend that men be informed of the risks and benefits of screening. The American Society of Clinical Oncology recommends screening be discouraged in those who are expected to live less than ten years, while in those with a life expectancy of greater than ten years a decision should be made by the person in question based on the potential risks and benefits. In general, they conclude that based on recent research, "it is uncertain whether the benefits associated with PSA testing for prostate cancer screening are worth the harms associated with screening and subsequent unnecessary treatment."
ZERO - The End of Prostate Cancer is a national, not-for-profit health care organization based in Washington, D.C.
A tumor marker is a substance found in the blood, urine, or body tissues that can be elevated in cancer, among other tissue types. There are many different tumor markers, each indicative of a particular disease process, and they are used in oncology to help detect the presence of cancer. An elevated level of a tumor marker can indicate cancer; however, there can also be other causes of the elevation.
Tumor markers can be produced directly by the tumor or by non-tumor cells as a response to the presence of a tumor. Most tumor markers are tumor antigens, but not all tumor antigens can be used as tumor markers.
Prostate cancer is a form of cancer that develops in the prostate, a gland in the male reproductive system. Most prostate cancers are slow growing; however, there are cases of aggressive prostate cancers. The cancer cells may metastasize (spread) from the prostate to other parts of the body, particularly the bones and lymph nodes. Prostate cancer may cause pain, difficulty in urinating, problems during sexual intercourse, or erectile dysfunction. Other symptoms can potentially develop during later stages of the disease.
Rates of detection of prostate cancers vary widely across the world, with South and East Asia detecting less frequently than in Europe, and especially the United States. Prostate cancer tends to develop in men over the age of fifty. Globally it is the sixth leading cause of cancer-related death in men (it is now the first in the UK and second in the United States). Prostate cancer is most common in the developed world with increasing rates in the developing world. However, many men with prostate cancer never have symptoms, undergo no therapy, and eventually die of other unrelated causes. Many factors, including genetics and diet, have been implicated in the development of prostate cancer.Recently the prevalence of light pollution has been implicated in the development of prostate cancer.