The recent screening trial from Europe helps answer this question. Initially, the study used digital rectal examination (DRE) and transrectal ultrasound as well as PSA, because it wasn’t known which test or combination of tests would give the best cancer pick-up rate. The PSA threshold for taking action was initially a level over 4 ng/mL. The study found that DRE added little to the pick-up rate, and that by dropping the PSA action level to 3 ng/mL and omitting the DRE, similar numbers of cancers were detected. Without a DRE, only 20% of screened men needed a biopsy, compared to 28% with DRE. This resulted in the following advantages: 1) avoiding a lot of unnecessary biopsies; 2) improving the pick-up rate for cancer from 18% to 24% in those who had a biopsy.
One could argue that adding DRE to a PSA threshold of 3 ng/mL would further increase the diagnosis rate. But in fact, the rise would likely only be marginal, and at a cost of again boosting the number of negative (thus unnecessary) biopsies. A good screening strategy should strike a balance between detecting cancer and not causing too much harm from over-investigation of men without cancer.
So, is the DRE dead? Not yet. Certainly, it’s important if you have any rectal bleeding or pain, and it helps determine prostate size for those with benign symptoms. Some authorities still consider it part of their screening recommendations, but the evidence to continue with it is weak. It’s particularly unhelpful when used alone without PSA, with no correlation to biopsy findings.
Being tested puts some guys off in the first place, while others may feel more at ease with it. As for me, I’m happy to forgo the DRE!
As one patient commented prior to submitting to the test: “It sounds so technical and modern, the ‘digital’ rectal examination, but you know what — it isn’t really, is it?”
