Digital rectal exam (DRE)
A urologist examines the prostate by putting a lubricated, gloved finger inside the rectum and feeling (palpating) the prostate through the rectal wall. This is called digital rectal exam (DRE).
It takes only a couple of minutes and should not be painful. If it feels uncomfortable, say so. The more experienced the urologist, the more he can tell from a rectal exam.
The rectal exam should be done after a PSA test. There's some chance that a rectal exam before a PSA test may elevate the PSA and create a false positive result.
Why do you need this test when the PSA blood test is available? Why not rely on the PSA test alone?
About 25 per cent of men who have prostate cancer have a low PSA. So the rectal exam is an essential follow up to PSA test.
The purpose of digital exam is to feel for "suspicious" places on the prostate.
The prostate has a base, an apex, an anterior, a posterior and two lateral surfaces. The base (the broad end) touches the lower surface of the bladder. The apex
points downward and is in contact with the fibrous tissue network between the skin and the underlying structure of muscle and bone of the urogenital diaphragm.
Urologists divide the prostate into zones -- the transition zone, central zone and peripheral zone. The peripheral zone can be felt through the rectum, especially when enlarged.
Benign Prostatic Hypertrophy is the abnormal enlargement of non-cancerous cells within the transition zone of the prostate.
Most prostate cancer occurs in the peripheral zone
Fortunately, this is the area most likely to be felt during a rectal exam. Nonetheless, as you can see from the illustration at the top of this page, the front and top parts of the prostate cannot be felt by DRE. Prostate cancer may occur there, and some prostate cancer in the peripheral zonealso is not detectable by feel. So the PSA test is essential too. Find out more about DRE from University of Pittsburgh Medical Center.
Find Life-Threatening Prostate Cancer by Measuring PSA Velocity During "Window of Curability" Nov 1, 2006.
This page made by J. Strax December 26, 2006. PAge last modified December 26, 2008.