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Home > Prostate cancer

1 The prostate

The prostate is a gland in a man's reproductive system. It makes and stores seminal fluid, a milky fluid that nourishes sperm. This fluid is released to form part of semen.

The prostate is about the size of a walnut. It is located below the urinary bladder and in front of the rectum. It surrounds the upper part of the urethra, the tube that empties urine from the bladder. If the prostate grows too large, the flow of urine can be slowed or stopped.

To work properly, the prostate needs male hormones ( androgens). Male hormones are responsible for male sex characteristics. The main male hormone is testosterone, which is made mainly by the testicles. Some male hormones are produced in small amounts by the adrenal glands.

Diagram of the prostate and nearby organs

2 Understanding the cancer process

Normally, cells grow and divide to form new cells in an orderly way. They perform their functions for a while, and then they die. This process helps keep the body healthy.

Sometimes, however, cells do not die. Instead, they keep dividing and creating new cells that the body does not need. They form a mass of tissue, called a growth or tumor.

Tumors can be benign or malignant:

• Benign tumors are not cancer. They can usually be removed, and in most cases, they do not come back. Cells from benign tumors do not spread to other parts of the body. Most important, benign tumors of the prostate are not a threat to life. Benign prostatic hyperplasia (BPH) is the abnormal growth of benign prostate cells. In BPH, the prostate grows larger and presses against the urethra and bladder, interfering with the normal flow of urine. More than half of the men in the United States between the ages of 60 and 70 and as many as 90 percent between the ages of 70 and 90 have symptoms of BPH. For some men, the symptoms may be severe enough to require treatment.

• Malignant tumors are cancer. Cells in these tumors are abnormal. They divide without control or order, and they do not die. They can invade and damage nearby tissues and organs. Also, cancer cells can break away from a malignant tumor and enter the bloodstream and lymphatic system. This is how cancer spreads from the original (primary) cancer site to form new (secondary) tumors in other organs. The spread of cancer is called metastasis.

When prostate cancer spreads (metastasizes) outside the prostate, cancer cells are often found in nearby lymph nodes. If the cancer has reached these nodes, it means that cancer cells may have spread to other parts of the body -- other lymph nodes and other organs, such as the bones, bladder, or rectum. When cancer spreads from its original location to another part of the body, the new tumor has the same kind of abnormal cells and the same name as the primary tumor. For example, if prostate cancer spreads to the bones, the cancer cells in the new tumor are prostate cancer cells. The disease is metastatic prostate cancer; it is not bone cancer.

3 Prostate cancer: who's at risk

The causes of prostate cancer are not well understood. Doctors cannot explain why one man gets prostate cancer and another does not.

Researchers are studying factors that may increase the risk of this disease. Studies have found that the following risk factors are associated with prostate cancer:

• Age. In the United States, prostate cancer is found mainly in men over age 55. The average age of patients at the time of diagnosis is 70.
• Family history of prostate cancer. A man's risk for developing prostate cancer is higher if his father or brother has had the disease.
• Race. This disease is much more common in African American men than in white men. It is less common in Asian and American Indian men.
• Diet and dietary factors. Some evidence suggests that a diet high in animal fat may increase the risk of prostate cancer and a diet high in fruits and vegetables may decrease the risk. Studies are in progress to learn whether men can reduce their risk of prostate cancer by taking certain dietary supplements.

Although a few studies suggested that having a vasectomy might increase a man's risk for prostate cancer, most studies do not support this finding. Scientists have studied whether benign prostatic hyperplasia, obesity, lack of exercise, smoking, radiation exposure, or a sexually transmitted virus might increase the risk for prostate cancer. At this time, there is little evidence that these factors contribute to an increased risk.

There is a lower occurrence of prostate cancer in men in less developed countries. It is speculated that the developed countries have higher levels of carcinogens in the environment that lead to the development of prostate cancer; men who move from less developed countries to more developed ones have an increased occurrence of prostate cancer.

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Topics: Prostate Cancer Tumor Doctor Cells Men Risk Symptoms Tumors...

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ProstateThe prostate is a gland that is part of male mammalian sex organs. Its main function is to secrete and store a clear, slightly acidic fluid that is part of semen. A healthy prostate is approximately the size of a walnut. It surrounds the urethra just belo Prostate cancerProstate cancer is the second most common type of cancer in men in the United States, after skin cancer. Of all the men who are diagnosed with cancer each year, more than one-fourth have prostate cancer. The prostate The prostate is a gland in a man's rep Prostate massageProstate massage involves massaging the prostate, one source of sexual pleasure in men relating to orgasm. This process involves massaging the prostate through the anus by hand, or with a vibrator. The prostate can also be indirectly massaged externally t Prostate specific antigenProstate specific antigen PSA is a protein manufactured exclusively by the prostate gland; PSA is produced for the ejaculate where it liquifies the semen and allows sperm cells to swim freely. It is also believed to be instrumental in desolving the cervic