A prostate exam typically includes a digital rectal exam (DRE). This is a fancy name for a very simple procedure that allows the doctor to physically feel the prostate gland to determine if it is enlarged, abnormally hard, or if there are any lumps or other irregularities.
In reality, the only thing that is "digital" in this fast test is the doctor's finger! A DRE is also part of the full prostate cancer screening process, which also usually includes a PSA test.
A DRE is important because some men with prostate cancer may not have a PSA level that is any cause for alarm. And some men with prostate cancer may have a totally normal DRE because small or early prostate cancers are very difficult for a doctor to feel (the medical term for this is not palpable).
While neither of these simple tests are 100% accurate, they are often a first step to help doctors determine if a man has prostate cancer.
Using a DRE alone, however, has been shown to be less accurate than PSA testing for detecting prostate cancer.