In UK now, the first genetic test for prostate cancer is being launched this week. The disease kills 10,000 men every year in that country.
The genetic test is considered more reliable than methods currently used to diagnose the disease. Doctors say the genetic test is a step closer to being able to screen all men for prostate cancer in the same way as women are routinely checked for breast and cervical cancer.
At present doctors use a blood test called the prostate specific antigen (PSA) test to check if men are at increased risk of cancer. The PSA test can indicate the presence of a prostate problem, which may sometimes turn out to be prostate cancer. The PSA test gives rise to a large number of false positive results, however. This leads to men having unnecessary biopsies carried out.
The new test, called the PCA3, is being marketed by the American company Gen-Probe and will have the backing of leading cancer experts and campaigners.
It looks for a gene in men's urine that is produced by prostate cancer cells. If the urine test is positive, this is a more accurate indication that the man has prostate cancer.
Roger Kirby, professor of urology at St George's hospital, London, said: "Although the PSA test gives us an indication of there being something wrong with the prostate, it does not always tell us if it is malignant. This new test, in combination with an examination of the prostate . . . tells us whether we should advise a biopsy."
Worldwide, more than 670,000 men are diagnosed with prostate cancer every year, accounting for one in nine of all new cancers in males. It is the second most common cancer in men after lung cancer.
Recent incidence rates are heavily influenced by the availability of PSA testing in the population and incidence varies far more than mortality. The highest incidence rates are in the United States and Sweden and the lowest rates are in China and India
Whether there is a real increase in incidence or not, the numbers of cases of prostate cancer will rise as the population at risk (older men) expands due to increasing life expectancy. But early detection will certainly help effective treatment.
If prostate cancer is detected during routine yearly exams with the PSA test or digital rectal examination (DRE), your cancer will likely be at an early, more treatable stage.
Since the use of early detection tests for prostate cancer became relatively common (about 1990), the prostate cancer death rate has dropped. However, it has not been proven that this is a direct result of screening. Studies are under way to try to confirm that early detection tests for prostate cancer in large groups of men will lower the prostate cancer death rate.