Diagnoses of metastatic prostate cancer in older men are on the rise after a record low in 2011, a new research study has found.
Led by Weill Cornell Medicine and New York-Presbyterian researchers, the study was published in JAMA Oncology in an article titled “Increase in Prostate Cancer Distant Metastases at Diagnosis in the United States.”
The findings suggest the increased incidence is likely related to the 2012 change in prostate cancer screening guidelines issued by the U.S. Preventative Services Task Force (USPSTF).
The new USPSTF guidelines stopped recommending routine prostate-specific antigen (PSA) testing, citing evidence the screening was not saving lives and often led to extra tests and treatments that actually had negative effects, including pain, incontinence, and impotence.
PSA tests measure how much prostate-specific antigen is in a patient’s blood. Elevated levels might indicate the presence of prostate cancer. PSA testing was included in general recommendations for prostate cancer diagnosis in the early 1990s for all men age 50 and older, and for men over age 40 with a history of prostate cancer in their family.
Since PSA screening was introduced, the incidence of metastatic prostate cancer diagnoses dropped about 70 percent and overall deaths from prostate cancer decreased by 50 percent.
In 2012, PSA testing was withdrawn from the annual physicals of healthy men of all ages.
To investigate the impact of this change in policy, the researchers used a national cancer database to identify 545,399 men older than 40 who were diagnosed with prostate cancer between 2004 and 2013.
They found that in men older than 75, both the incidence of metastatic prostate cancer and the proportion of men with aggressive cancer had increased since 2011 – before the new recommendations were issued.
Based on these findings, the authors emphasize the need for healthcare policy leaders to re-evaluate their approach to prostate cancer screenings.
“It’s what most of us would have predicted, although somewhat sooner,” Dr. Jim Hu, PhD, the lead author who conducted the study in collaboration with senior author Dr. Art Sedrakyan, PhD, said in a press release. Both men are professors at Weill Cornell Medicine.
“There was a decrease in prostate cancer metastasis and death after the advent of PSA testing. Remove the screening and the rates of serious disease rise again,” Hu said.
After studying data from the Surveillance, Epidemiology and End Results program, a National Cancer Institute (NCI) database that tracks cancer incidence, the researchers found that the reduction in PSA screening has altered the way prostate cancer now presents in a significant way. While only 7.8 percent of prostate cancer patients over age 75 were diagnosed with metastatic prostate cancer in 2011, and 68.9 percent had aggressive cancer, these numbers rose to 12 percent and 72 percent, respectively, in 2013.
These changes in the rate of metastatic prostate cancer were only found in men older than 75. The authors believe this doesn’t necessarily exclude the value of PSA screening in younger men, but might mean that more time is necessary to draw conclusions.
The authors said their most important finding is that the incidence of metastatic prostate cancer is rising, and while the PSA tests are not perfect, they are not useless in the diagnosis of prostate cancer.
And, they added, prostate cancer therapy has evolved and the negative consequences of treatment have been reduced. Besides, there is new evidence showing that some early-stage prostate cancers are slow-growing and can be managed with surveillance alone, limiting risks for patients.
“Currently, up to 50 percent of Americans diagnosed with prostate cancer now choose active surveillance; however, the implication of our study is that it is important to have the right to choose screening in order to know whether a man may have an aggressive or indolent prostate cancer,” Hu said. “The burden of overtreatment and side effects may no longer be sufficient to recommend against routine screening.”