Prostate Cancer Defined
The body is made up of many types of cells. Normally, cells grow, divide, and produce more cells as needed to keep the body healthy and functioning properly. Sometimes, however, the process goes wrong -- cells become abnormal and form more cells in an uncontrolled way.

These extra cells form a mass of tissue, called a growth or Tumor. Tumors can be Benign, which means not cancerous, or Malignant, which means cancerous. Prostate cancer occurs when a malignant tumor forms in the tissue of the prostate, a gland in the male reproductive system. In its early stage, prostate cancer needs the male hormone Testosterone to grow and survive.

The prostate is about the size of a large walnut. It is located below the Bladder and in front of the rectum. The prostate's main function is to make fluid for semen, a white substance that carries sperm.

Prostate cancer is one of the most common types of cancer among American men. It is a slow-growing disease that mostly affects older men. In fact, more than 65 percent of all prostate cancers are found in men over the age of 65. The disease rarely occurs in men younger than 40 years of age.

Sometimes, cancer cells break away from a malignant tumor in the prostate and enter the bloodstream or the lymphatic system and travel to other organs in the body.

When cancer spreads from its original location in the prostate to another part of the body such as the bone, it is called metastatic prostate cancer -- not bone cancer. Doctors sometimes call this "distant" disease.

Today, more men are surviving prostate cancer than ever before. Treatment can be effective, especially when the cancer has not spread beyond the region of the prostate.

Causes and Risk Factors
Scientists don't know exactly what causes prostate cancer. They cannot explain why one man gets prostate cancer and another does not. However, they have been able to identify some risk factors that are associated with the disease. A risk factor is anything that increases your chances of getting a disease.

Age is the most important risk factor for prostate cancer. The disease is extremely rare in men under age 40, but the risk increases greatly with age. More than 65 percent of cases are diagnosed in men over age 65. The average age at the time of diagnosis is 70.

Race is another major risk factor. In the United States, this disease is much more common in African American men than in any other group of men. It is least common in Asian and American Indian men.

A man's risk for developing prostate cancer is higher if his father or brother has had the disease.

Diet also may play a role. There is some evidence 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 to find out whether men can reduce their risk of prostate cancer by taking certain dietary supplements are ongoing.

Scientists have wondered whether an enlarged prostate, a condition also known as benign prostatic hyperplasia or BPH, might increase the risk for prostate cancer. They have also studied Obesity, lack of Exercise, smoking, radiation exposure, and a sexually transmitted virus to see if they might increase risk. But at this time, there is little evidence that any of these factors contribute to an increased risk.