Cancer begins when normal cells in the prostate change and grow uncontrollably, forming a mass called a tumor. A tumor can be benign (noncancerous) or malignant (cancerous, meaning it can spread to other parts of the body).

About the prostate gland

The prostate is a walnut-sized gland located behind the base of a man’s penis, in front of the rectum, and below the bladder. It surrounds the urethra, the tube-like channel that carries urine and semen through the penis. The prostate's main function is to make seminal fluid, the liquid in semen that protects, supports, and helps transport sperm.

Types of prostate cancer

Prostate cancer is a malignant tumor that begins in the prostate gland. Some prostate cancers grow very slowly and may not cause symptoms or problems for years. Many times, when a man develops prostate cancer much later in life, it is unlikely to cause symptoms or shorten the man’s life, and aggressive treatment may not be needed. For this reason, early detection for prostate cancer with prostate specific antigen (PSA) testing in men who don’t have symptoms of the disease is controversial. PSA is found in higher-than-normal levels in men with various prostate conditions, including benign prostatic hyperplasia (BPH, an enlarged prostate), inflammation or infection of the prostate, and prostate cancer (see Risk Factors and Prevention)

Prostate cancer is somewhat unusual, compared with other types of cancer, because many tumors do not spread from the prostate. And often, even metastatic prostate cancer can be successfully treated, allowing men with prostate cancer to live with good health for several years. However, if the cancer does metastasize (spread) to other parts of the body and is not well controlled with treatment, it can cause pain, fatigue, and other symptoms.

More than 95% of prostate cancers are a type called adenocarcinomas. A rare type of prostate cancer known as neuroendocrine cancer or small cell anaplastic cancer tends to spread earlier but usually does not make PSA. Read more about neuroendocrine tumors.

Find out more about basic cancer terms used in this section.

Looking for More of an Overview?

If you would like additional introductory information, explore these related items on Cancer.Net:

• ASCO Answers Fact Sheet: Read a one-page fact sheet (available in PDF) that offers an easy-to-print introduction for this type of cancer.

• Cancer.Net Patient Education Video: View a short video led by an ASCO expert in this type of cancer that provides basic information and areas of research.

• Cancer.Net En Español: Read about prostate cancer in Spanish or a one-page summary in an ASCO Answers Fact Sheet in Spanish. Infórmase sobre cáncer de próstata en español o una hoja informativa de una página, Respuestas sobre el cáncer.

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