Other than skin cancer, prostate cancer is the most common type of cancer in U.S. men. Early detection and improvements in therapy have resulted in a dramatic decrease in prostate cancer deaths (by 40 to 50 percent) since the early 1990s.
Detecting Prostate Cancer Early
One of the best ways to detect prostate cancer early is through screening, which is testing to find a disease in people with no symptoms. Screening can help find some types of cancer at an early stage, when they may have a better prognosis. In fact, screening alone is credited for one third of the recent decrease in prostate cancer deaths, accounting for about 10,000 lives saved in 2010.
Two of the most common screening tests for prostate cancer are the digital rectal exam (DRE) and the prostate-specific antigen (PSA) test. Since the PSA test was introduced in the late 1980s, doctors have commonly used it in conjunction with a DRE to screen for prostate cancer. Because the DRE can sometimes find cancers in men with normal PSA levels, doctors often suggest that men have both tests.
Ultimately, decisions about screening should be individualized based on your level of risk, overall health, and life expectancy, as well as your desire for treatment if you are diagnosed with prostate cancer.
Digital Rectal Exam
For a DRE, a doctor inserts a gloved, lubricated finger into the rectum to feel the prostate gland. Many prostate cancers begin in the back of the prostate, and a DRE may be used to assess the texture of this part of the gland and check for any bumps (nodules) or hard areas there that might be cancer. This exam usually isn’t painful and only takes a few seconds.
In addition to being combined with the PSA test to screen for prostate cancer, a DRE can also be used in men with prostate cancer to try to determine if the disease has spread to nearby tissues or to detect cancer that has come back after treatment.
The PSA test is a blood test that measures a protein released in the blood by prostate cells. Although both normal and malignant (cancerous) prostate cells secrete the protein, higher PSA levels may indicate the probability of cancer. While there is no perfect screening test for prostate cancer, PSA is the best indicator available.
If you have any questions about whether the PSA test is right for you, talk with your doctor about the benefits and risks. Learn more about PSA screening.
Preventing Prostate Cancer
The exact cause of prostate cancer is unknown, and many prostate cancer risk factors cannot be controlled, so it is not possible to prevent the disease. However, there are some things you can do, such as eat a healthy diet and exercise, that might help lower your risk (and might help you deal with the disease if you do develop it). The section on diet and exercise for men with prostate cancer may also help those who do not have the disease.
In 2003, a study called the Prostate Cancer Prevention Trial demonstrated that hormone therapy with finasteride (Proscar) reduced the risk of developing prostate cancer by 25 percent. Finasteride is approved for the treatment of benign prostatic hyperplasia (BPH), a noncancerous enlargement of the prostate. This study was the first to show that a drug could be used to prevent prostate cancer.
In 2010, a similar drug, dutasteride (Avodart), was also found to reduce the risk of prostate cancer in men at higher-than-average risk for the disease.
However, there are potential side effects, and men who developed prostate cancer while on these medications were more likely to have higher-grade cancer. As a result, the use of finasteride and dutasteride in cancer prevention has not been well accepted.