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NIH MedlinePlus the Magazine, Trusted Health Information from the National Institutes of Health

Prostate Cancer

Progress Against Prostate Cancer

Diagram of prostate cancer

Click to enlarge. Illustration: NIDDK

What Is the Prostate?

The prostate is a walnut-sized gland that only men have. It is part of the reproductive system that makes the fluid that carries sperm. As you can see in the picture (upper right), the prostate is located just below the bladder. The urethra (the tube carrying urine from the bladder to outside the body) runs through the center of the prostate. As men age, the prostate tends to increase in size. This can narrow the urethra, decreasing urine flow.

Prostate cancer is made up of cells the body does not need, forming a mass of tissue called a tumor. Cancer cells sometimes spread to other parts of the body, multiply, and cause death.

African American men are about 60 percent likelier to develop prostate cancer than white men. However, age is the greatest risk factor for prostate cancer, with nearly 92 percent of those diagnosed being 45 or older.

What Is PSA?

Prostate specific antigen, or PSA, is a substance produced by the prostate and released into the blood. PSA levels are often high in men with prostate cancer. However, PSA can also be high with other prostate conditions.

There is a simple blood test to measure for PSA levels. Typically, the higher the PSA level, the more likely there is a prostate problem. But age and race can affect PSA levels. And some prostates produce more PSA than others. PSA levels can also be affected by certain medical procedures, an enlarged prostate, or a prostate infection.

Since there are many contributing factors, your healthcare provider is the best person to test and interpret your PSA level.

Fast Facts

  • Prostate cancer occurs when malignant (cancer-forming) cells grow in the tissue of the prostate gland—a part of the male reproductive system that sits below the bladder and in front of the rectum. A healthy prostate is about the size of a walnut. As men age, their prostate grows in size.
  • Growths in the prostate can be benign or malignant. Benign growths are not cancerous, but they can make urinating difficult. They are common, do not spread, and can be removed. A malignant tumor in the prostate can be life threatening and invade other tissue and organs. It can be removed but sometimes returns.
  • Prostate cancer is the second most common type of cancer among men in the United States. One out of six American men will be diagnosed with prostate cancer during their lifetimes.
  • The National Cancer Institute estimates 192,280 men will be diagnosed with prostate cancer for 2009.

Fast Facts

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Winter 2010 Issue: Volume 5 Number 1 Page 22