March 29, 2011 — The "excessive" use of prostate-specific antigen (PSA) screening in elderly men with limited life expectancies is a "significant problem" in the United States, according to a new study of men 40 years and older who participated in the National Health Interview Survey.
About three quarters of a million men are unnecessarily and inappropriately screened each year in the United States, the study authors estimate.
The study, which was published online March 28 in the Journal of Clinical Oncology, also found that men in their 70s were nearly twice as likely as men in their early 50s to have undergone PSA testing in the year before taking the survey (45.5% vs 24.0%).
What this means is that "the men most likely to benefit from PSA screening are paradoxically being screened at markedly lower rates than men highly unlikely to benefit," write the authors, who are led by Michael Drazer, MD, from the University of Chicago Medical Center in Illinois.
The evidence that supports this comment comes from the interim results of the landmark European Randomized Study of Screening for Prostate Cancer (ERSPC), which showed a 20% reduction in cancer-specific mortality for screened men — but only for those 55 to 69 years of age.
The ERSPC is currently the only randomized controlled study to show a disease-specific mortality benefit from screening.
Overall, Dr. Drazer and colleagues report that, in the United States, PSA-based prostate cancer screening patterns are "discordant with recommended guidelines."
The American Urological Association and American Cancer Society recommend, based on expert opinion, screening men with at least 10 years of estimated life expectancy. The US Preventive Services Task Force recently suggested that routine screening be stopped at 75 years of age.
The researchers found that, among men who were 70 years and older with "low" 5-year life expectancies, 30.7% were nonetheless tested for PSA — which is not in keeping with the above guidelines. The authors calculate that about 777,000 men of this age and life expectancy are unnecessarily tested every year in the United States, which then results in a lot of unneeded biopsies and treatment.
They speculate that a possible explanation for this is that physicians are "notoriously poor" at estimating life expectancy and that the screening might represent "defensive medicine."
The problem is not going away, suggested a high-profile oncologist not involved in the study.
"The underuse of PSA testing in younger men and the often unnecessary overtreatment of older men with indolent prostate cancer that will most likely never bother them remain huge concerns for oncologists," said Nicholas Vogelzang, MD, in a press statement. Dr. Vogelzang is from the Nevada Cancer Institute in Las Vegas and is a member of the American Society for Clinical Oncology communications committee.
Study Source and Measures
The goal of the new study was to detail the rates and predictors of PSA screening among older men in the United States. Men were counted as having had a screening if they reported receiving the PSA test as part of a routine physical exam in the year before the survey.
The authors acknowledge that the inability to verify the PSA test was a limitation of the study. However, they also say that the overreporting and underreporting tend to cancel themselves out. "It is likely our data are good estimates," they write.
The data source, the National Health Interview Survey, is a household survey administered through a series of face-to-face interviews conducted by employees of the US Census Bureau. The cancer screening survey is administered every 5 years as a supplement to the standard survey.
Using responses from the 2000 and 2005 surveys, the authors did most of their analyses on 2623 men older than 70 years, representing the 8 million men that age in the United States in 2000 and the 8.1 million in 2005.
Five-year life expectancy was measured with a "validated mortality index," which was based on survey data that included age, sex, smoking status, body mass index, comorbidities, recent hospitalizations, self-perceived health, and functional status measures. The index categorized 5-year mortality risk as high (risk of mortality of 48% or more), intermediate (16% to 47%), or low (15% or less).
The investigators found that the PSA screening rate was lowest among men 40 to 44 years (7.5%), and increased steadily with age until a peak of 45.5% among men 70 to 74 years. Screening rates then gradually declined by age, with 24.6% of men 85 years and older reporting a screening. Notably, this screening rate among 85-year-old men was comparable to that of men 50 to 54 years (24.0%).
Among men 70 years or older, screening rates varied by estimated 5-year life expectancy; they were 47.3% in men with high life expectancies, 39.2% in men with intermediate life expectancies, and 30.7% in men with low life expectancies.
"Our findings show a high rate of elderly and sometimes ill men being inappropriately screened for prostate cancer. We're concerned these screenings may prompt cancer treatment among elderly men who ultimately have a very low likelihood of benefiting the patient and paradoxically can cause more harm than good," said coauthor Scott E. Eggener, MD, from the University of Chicago Medical Center, in a press statement.
In multivariate analysis, the authors also found that estimated life expectancy and age were independently associated with PSA screening (P < .001 for each).
Dr. Eggener reports receiving honoraria and research funding from Centocor Ortho Biotech and AstraZeneca, and research funding from Visualase.
J Clin Oncol. Published online March 28, 2011.
About three quarters of a million men are unnecessarily and inappropriately screened each year in the United States, the study authors estimate.
The study, which was published online March 28 in the Journal of Clinical Oncology, also found that men in their 70s were nearly twice as likely as men in their early 50s to have undergone PSA testing in the year before taking the survey (45.5% vs 24.0%).
What this means is that "the men most likely to benefit from PSA screening are paradoxically being screened at markedly lower rates than men highly unlikely to benefit," write the authors, who are led by Michael Drazer, MD, from the University of Chicago Medical Center in Illinois.
The evidence that supports this comment comes from the interim results of the landmark European Randomized Study of Screening for Prostate Cancer (ERSPC), which showed a 20% reduction in cancer-specific mortality for screened men — but only for those 55 to 69 years of age.
The ERSPC is currently the only randomized controlled study to show a disease-specific mortality benefit from screening.
Overall, Dr. Drazer and colleagues report that, in the United States, PSA-based prostate cancer screening patterns are "discordant with recommended guidelines."
The American Urological Association and American Cancer Society recommend, based on expert opinion, screening men with at least 10 years of estimated life expectancy. The US Preventive Services Task Force recently suggested that routine screening be stopped at 75 years of age.
The researchers found that, among men who were 70 years and older with "low" 5-year life expectancies, 30.7% were nonetheless tested for PSA — which is not in keeping with the above guidelines. The authors calculate that about 777,000 men of this age and life expectancy are unnecessarily tested every year in the United States, which then results in a lot of unneeded biopsies and treatment.
They speculate that a possible explanation for this is that physicians are "notoriously poor" at estimating life expectancy and that the screening might represent "defensive medicine."
The problem is not going away, suggested a high-profile oncologist not involved in the study.
"The underuse of PSA testing in younger men and the often unnecessary overtreatment of older men with indolent prostate cancer that will most likely never bother them remain huge concerns for oncologists," said Nicholas Vogelzang, MD, in a press statement. Dr. Vogelzang is from the Nevada Cancer Institute in Las Vegas and is a member of the American Society for Clinical Oncology communications committee.
Study Source and Measures
The goal of the new study was to detail the rates and predictors of PSA screening among older men in the United States. Men were counted as having had a screening if they reported receiving the PSA test as part of a routine physical exam in the year before the survey.
The authors acknowledge that the inability to verify the PSA test was a limitation of the study. However, they also say that the overreporting and underreporting tend to cancel themselves out. "It is likely our data are good estimates," they write.
The data source, the National Health Interview Survey, is a household survey administered through a series of face-to-face interviews conducted by employees of the US Census Bureau. The cancer screening survey is administered every 5 years as a supplement to the standard survey.
Using responses from the 2000 and 2005 surveys, the authors did most of their analyses on 2623 men older than 70 years, representing the 8 million men that age in the United States in 2000 and the 8.1 million in 2005.
Five-year life expectancy was measured with a "validated mortality index," which was based on survey data that included age, sex, smoking status, body mass index, comorbidities, recent hospitalizations, self-perceived health, and functional status measures. The index categorized 5-year mortality risk as high (risk of mortality of 48% or more), intermediate (16% to 47%), or low (15% or less).
The investigators found that the PSA screening rate was lowest among men 40 to 44 years (7.5%), and increased steadily with age until a peak of 45.5% among men 70 to 74 years. Screening rates then gradually declined by age, with 24.6% of men 85 years and older reporting a screening. Notably, this screening rate among 85-year-old men was comparable to that of men 50 to 54 years (24.0%).
Among men 70 years or older, screening rates varied by estimated 5-year life expectancy; they were 47.3% in men with high life expectancies, 39.2% in men with intermediate life expectancies, and 30.7% in men with low life expectancies.
"Our findings show a high rate of elderly and sometimes ill men being inappropriately screened for prostate cancer. We're concerned these screenings may prompt cancer treatment among elderly men who ultimately have a very low likelihood of benefiting the patient and paradoxically can cause more harm than good," said coauthor Scott E. Eggener, MD, from the University of Chicago Medical Center, in a press statement.
In multivariate analysis, the authors also found that estimated life expectancy and age were independently associated with PSA screening (P < .001 for each).
Dr. Eggener reports receiving honoraria and research funding from Centocor Ortho Biotech and AstraZeneca, and research funding from Visualase.
J Clin Oncol. Published online March 28, 2011.
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