Rectal exams for prostate cancer may miss early cases of the disease, according to new research.
A digital rectal exam involves a medical professional inserting a finger into a man’s buttocks to check the prostate gland for any unusual swelling or nodules that may indicate cancer.
In the UK there is no national prostate cancer screening program and some men get these rectal checks.
Another test that may be offered to NHS patients is the prostate-specific antigen (PSA) blood test.
An elevated level of PSA in the blood can indicate a problem with the prostate, but it does not always indicate cancer.
In the new study, presented at the annual conference of the European Association of Urology in Milan, Italy, experts from Germany said only rectal exams can miss cancer cases and should not be used as the sole method of screening.
The Probase study, led by the German Cancer Research Center in Heidelberg, involved 46,495 men aged 45 who were enrolled between 2014 and 2019.
Half were offered a PSA test at age 45, while the other half were offered a rectal exam followed by a delayed PSA screening at age 50.
The results showed that a PSA test was about four times better at detecting cancer than a rectal exam.
Dr. Agne Krilaviciute, lead author of the study, said: “One of the main reasons for prostate cancer screening is to detect it in patients as early as possible, as this can lead to better treatment outcomes.
“But our study suggests that the DRE (digital rectal exam) is just not sensitive enough to detect those cancers at an early stage.
“The DRE gave a negative result in 99% of cases and even those considered suspicious had a low detection rate.
“Results we’ve seen from the Probase trial show that PSA testing detected four times more prostate cancer at age 45.”
The researchers think that one of the reasons the DRE fails to detect cancer, especially in younger men, is that the tissue changes in the prostate are too small to detect with a finger.
Some cancers also occur in a part of the prostate that can’t be easily reached with a finger, they said.
Professor Peter Albers, a urologist from the University of Düsseldorf who was the study’s lead author, said: “Early-stage cancer may not have the size and stiffness to be felt.
“Separate analysis that used MRI scans prior to biopsies to locate cancers in the prostate showed that about 80% of these are in an area that should be easy to reach with a finger and that cancers were still undetectable by DRE.”
Amy Rylance, head of care improvement at Prostate Cancer UK, said: “This research supports the existing evidence that digital rectal exams are not the most effective way to diagnose prostate cancer.
“The good news is that standard practice on the NHS is for men to have a PSA blood test initially, followed by an MRI scan.
“While the DRE can sometimes add useful information to aid physicians in their clinical decision-making, it is no longer done routinely.
“There is currently no screening program for prostate cancer, which is why Prostate Cancer UK is committed to driving the research and evidence needed to make this a reality and save thousands of men’s lives.
“Until then, men at higher risk have the right to request a free PSA test from their GP – to find out if you are at higher risk, do the Prostate Cancer UK 30 sec online risk checker.”