Death rates from prostate cancer - the most commonly diagnosed cancer in men - have stabilized or declined in dozens of countries since the turn of the century, the American Cancer Society reported on Tuesday.
In 33 of 44 countries surveyed, the incidence of prostate cancer had stabilized in the last five years for which data was available - and in seven countries, it was down, the report found. Only four of the countries surveyed, including Bulgaria, saw an increased incidence of prostate cancer, it said.
"In the most recent five years of data examined, prostate cancer incidence and mortality rates are decreasing or stabilizing in most parts of the world," the study's author MaryBeth Freeman said. Prostate cancer deaths were down in 14 countries surveyed and stable in 54 others. Only three countries experienced a rise in prostate cancer deaths, according to the study findings, which were presented on Tuesday at a conference in Atlanta.
The United States had the biggest drop in prostate cancers, which Freeman attributed to a decline in the use of a controversial diagnostic test that identified too many non-dangerous tumors. The incidence of prostate cancers rose in the US during the 1980s and early 1990s when the PSA, or Prostate-Specific Antigen, blood test became widely available.
The test is imprecise, however, and yields too many false positives. It identifies higher than normal levels of PSA, a protein produced by the prostate, which could be a sign of cancer but is more often a symptom of other diseases.
Moreover, some prostate cancers are not aggressive and do not grow enough to pose a risk.
A false positive, on the other hand, can have harmful consequences for the patient: anxiety, complications linked to biopsies or anti-cancer treatments.
In 2012, the US Preventive Services Task Force, an expert panel that reviews the effectiveness of preventive clinical services, advised against use of the PSA test.