Rates of prostate cancer cases and deaths have declined or stabilized in many countries. And the United States had the largest recent decrease in disease incidence, a new study says.
“Previous studies have indicated significant variation in prostate cancer rates, due to factors including detection practices, availability of treatment, and genetic factors,” said study author MaryBeth Freeman. She’s a senior associate scientist for surveillance research at the American Cancer Society.
“By comparing rates from different countries, we can assess differences in detection practices and improvements in treatment,” Freeman said in a news release from the American Association for Cancer Research (AACR).
Researchers examined long-term and short-term data from 44 countries with incidence data and 71 countries with prostate cancer death data.
Of the 44 countries assessed for incidence, prostate cancer rates rose in four countries and fell in seven, with the United States with the biggest decrease. Rates remained stable in the other 33 countries.
Of the 71 countries assessed for prostate cancer death rates, there were decreases in 14, increases in three, and no change in 54.
As of 2012, prostate cancer was the most commonly diagnosed cancer among men in 96 countries and the leading cause of death in 51 countries, according to the study.
Freeman said the findings confirm the benefits of prostate-specific antigen (PSA) screening. She noted that in the United States, incidence rates rose from the 1980s to the early 1990s, then declined from the mid-2000s through 2015, largely due to increased use of PSA screening.
This type of screening is less available in poorer nations, meaning that men there are more likely to be diagnosed at later stages of prostate cancer and more likely to die, Freeman said.
She noted that some nations plan to scale back recommendations for PSA screening due to fears about possible overtreatment of prostate cancer that would never cause symptoms.
Dr. Eric Horwitz, professor of medicine at Fox Chase Cancer Center in Philadelphia, said this line of thinking is “potentially problematic.”
The U.S. Preventive Services Task Force recommends that men aged 55 to 69 undergo periodic screening after they’ve discussed the risks and benefits with their doctor.
“The screening recommendations were changed recently after further analysis of the U.S. data and we are now seeing more high-risk prostate cancer diagnoses that require treatment,” said Horwitz, who wasn’t involved with the study.
Freeman said future studies should monitor trends in mortality rates and late-stage disease to assess the impact of reduction in PSA testing in several countries.
The study was to be presented Tuesday at the AACR annual meeting, in Atlanta. Data and conclusions presented at meetings are usually considered preliminary until published in a peer-reviewed medical journal.
The U.S. National Cancer Institute has more on prostate cancer.