In a DRE, the physician inserts a lubricated, gloved finger into the rectum to feel the surface of the prostate gland. Healthy prostate tissue is soft, like the fleshy tissue of the hand where the thumb joins the palm.
Malignant tissue is firm, hard, and often asymmetrical or stony, like the bridge of the nose.
The accuracy of the test relies on the physician's ability to interpret what he or she feels. A special probe is inserted through the rectum and projects ultrasonic impulses against the prostate. TRUS and DRE together are effective screening tools for detecting prostate cancer. The PSA test result alone is not conclusive. The test measures the amount of PSA in the blood.