A prostate exam checks for signs of prostate cancer, an enlarged prostate, and infection or inflammation in the prostate gland. It typically involves two parts: a physical exam where a doctor feels the prostate through the rectal wall, and a blood test that measures a protein linked to prostate problems. Together, these give your doctor a picture of your prostate’s size, shape, texture, and cellular activity.
What the Physical Exam Checks For
The digital rectal exam, or DRE, is the hands-on portion. Your doctor inserts a lubricated, gloved finger into the rectum to feel the prostate gland, which sits just in front of the rectal wall and below the bladder. This positioning makes it one of the few organs a doctor can directly feel without imaging equipment.
A healthy prostate is about 3.5 centimeters wide and protrudes roughly 1 centimeter into the rectal space. It should feel rubbery and firm with a smooth surface, and there should be a noticeable groove (called a sulcus) running between the left and right lobes. Your doctor is checking for deviations from that baseline: lumps or hard nodules that could suggest cancer, a uniformly enlarged gland that points to benign prostatic hyperplasia (BPH), or tenderness and swelling that indicate infection or inflammation (prostatitis). The exam also checks the rectal walls themselves and notes whether there’s any blood on the glove afterward.
What the Blood Test Measures
The PSA test measures levels of prostate-specific antigen, a protein produced by both normal and cancerous prostate cells. Every man has some PSA in his blood, and the amount naturally rises with age. What matters is whether your level is higher than expected for your age group.
PSA levels are measured in nanograms per milliliter (ng/mL). As a rough reference, the upper end of normal for men in their 40s is around 1.5 ng/mL, rising to about 3 ng/mL in the 50s, around 4 ng/mL in the 60s, and roughly 5.5 ng/mL in the 70s. These aren’t hard cutoffs. A high reading doesn’t automatically mean cancer, and a normal reading doesn’t guarantee you’re cancer-free. Elevated PSA can also result from an enlarged prostate, a prostate infection, urinary tract infections, or even certain medications.
The higher the PSA level climbs, though, the more likely it is that cancer is involved. That’s why the number is used alongside the physical exam rather than on its own.
What the Exam Can Detect
The combination of a DRE and PSA test screens for three main conditions:
- Prostate cancer. Hard nodules felt during the DRE or a significantly elevated PSA level can both raise suspicion. Neither one confirms cancer by itself, but together they help your doctor decide whether further testing is needed.
- Benign prostatic hyperplasia (BPH). This is a non-cancerous enlargement of the prostate that becomes increasingly common after age 50. During the DRE, the gland feels uniformly larger but still smooth. BPH can also push PSA levels modestly higher.
- Prostatitis. Inflammation or infection of the prostate makes the gland feel boggy, swollen, or tender during the physical exam. Your doctor may press on the prostate to express fluid from the urethra for testing. PSA can spike during active prostatitis as well.
What the Exam Feels Like
The DRE itself takes less than a minute. You’ll either stand and bend forward at the waist or lie on your side with your knees drawn up. The doctor parts the buttocks, applies lubricating gel to a gloved index finger, and gently presses against the anal margin before sliding the finger in. You’ll feel pressure and possibly a brief urge to urinate as the doctor presses against the prostate. It’s uncomfortable but not typically painful unless there’s active inflammation.
The entire office visit, including going over your medical history, discussing symptoms, and reviewing PSA results if blood was drawn, usually runs about 20 to 30 minutes. Taking slow, deep breaths during the DRE helps relax the pelvic muscles and makes the exam go more smoothly. No special preparation is required beforehand.
When Screening Should Start
The American Urological Association recommends that men at average risk have a baseline PSA test between ages 45 and 50. From age 50 to 69, screening every two to four years is recommended for most men.
If you’re at higher risk, screening should start earlier, between ages 40 and 45. Risk factors that warrant earlier screening include being Black (which carries both a higher incidence and a higher risk of aggressive disease), having a strong family history of prostate cancer, or carrying certain inherited gene mutations. Men in these groups may also benefit from annual screening rather than every two to four years, though the decision involves weighing the benefits of early detection against the chance of overdiagnosis, particularly for older men.
What Happens After an Abnormal Result
An abnormal finding on either the DRE or the PSA test doesn’t mean you have cancer. It means your doctor needs more information. The next step is usually a prostate MRI, which creates detailed images of the gland to identify suspicious areas. If the MRI shows something concerning, a targeted biopsy follows, where small tissue samples are taken and examined under a microscope. This is the only way to confirm or rule out prostate cancer definitively.
In many cases, a mildly elevated PSA leads to a repeat blood test in a few months rather than an immediate biopsy. PSA can fluctuate from infections, recent ejaculation, vigorous exercise, or even prolonged sitting like a long bike ride. A single elevated reading in the absence of other warning signs is often monitored over time before more invasive steps are taken.