- What is prostate cancer?
- What are the risk factors for prostate cancer?
- Can prostate cancer be prevented?
- Finding prostate cancer early
- What tests can detect prostate cancer early?
- American Cancer Society recommendations for prostate cancer early detection
- If prostate cancer screening test results aren’t normal
- What are the signs and symptoms of prostate cancer?
- Insurance coverage for prostate cancer screening
- Additional resources
What is prostate cancer?
To understand prostate cancer, it helps to know about the prostate and nearby structures in the body. The prostate is a gland found only in males. It is located below the urinary bladder and in front of the rectum. The size of the prostate changes with age. In younger men, it is about the size of a walnut, but it can be much larger in older men.
The prostate’s job is to make some of the fluid that protects and nourishes sperm cells in semen, making the semen more liquid. Just behind the prostate are glands called seminal vesicles that make most of the fluid for semen. The urethra, the tube that carries urine and semen out of the body through the penis, goes through the center of the prostate.
The prostate starts to develop before birth. It grows rapidly during puberty, fueled by male hormones (called androgens). The main androgen, testosterone, is made in the testicles. The enzyme 5-alpha reductase converts testosterone into dihydrotestosterone (DHT). DHT is the main hormone that signals the prostate to grow.
The prostate usually stays at about the same size or grows slowly in adults, as long as male hormones are present.
Benign prostatic hyperplasia (BPH)
The inner part of the prostate (around the urethra) often keeps growing as men get older, which can lead to a common condition called benign prostatic hyperplasia (BPH). In BPH, the prostate tissue can press on the urethra, leading to problems urinating.
BPH is not cancer and does not develop into cancer. But it can be a serious problem for some men. If it requires treatment, drugs can often shrink the prostate or to relax the muscles within it, which usually helps with urine flow. If drugs aren’t helpful, some type of surgery, such as a transurethral resection of the prostate (TURP) may be needed.
Several types of cells are found in the prostate, but almost all prostate cancers develop from the gland cells, which are the cells that make the prostate fluid that is added to the semen. The medical term for a cancer that starts in gland cells is adenocarcinoma.
Other types of cancer can also start in the prostate gland, including sarcomas, small cell carcinomas, and transitional cell carcinomas. But these other types of prostate cancer are so rare that if you have prostate cancer it is almost certain to be an adenocarcinoma.
Some prostate cancers can grow and spread quickly, but most grow slowly. In fact, autopsy studies show that many older men (and even some younger men) who died of other diseases also had prostate cancer that never affected them. In many cases neither they nor their doctors even knew they had it.
Last Medical Review: 10/17/2014
Last Revised: 01/06/2015