Making the Grade with the Gleason Score
Adapted From:Prostate Cancer For Dummies

When men who have prostate cancer talk to each other, they sometimes exchange their Gleason scores or their cancer stages with an intensity that two combat veterans might use when exchanging the name of a battle they both served in. They say such things as “I’m a Gleason 6,” or maybe “I’m a Gleason 4” — rather than saying that they were at the battle of Khe San in Vietnam or in the Gulf War. This new prostate cancer identity is now more important than where these cancer veterans are from, how much money they make, or even what type of job they have. Cancer trumps everything.

“So what is the Gleason score, and how does it work?” you ask. Read on!

Getting the scoop on the score
The Gleason score was invented in 1966 by Dr. Donald Gleason, a pathologist. He based the score on information derived from studies of the biopsies of nearly 3,000 patients who had been diagnosed with prostate cancer. Pathologists worldwide rely on the Gleason score. The score provides an effective measurement that helps your doctor determine how severe your prostate cancer is, based on the appearance of the cancer cells when viewed under a microscope. All cancer looks abnormal to a pathologist, but low-grade cancers have cells that often look similar to healthy cells from the gland or organ that has been affected by the cancer. As a result, the pathologist can recognize that she’s looking at prostate cells under the microscope. But when the cancer is aggressive, the cancer cells look less and less like normal prostate cells (or any other kind of cells).

Pathologists find the Gleason grading system to be very reliable. For example, if the Gleason score indicates that the cancer is an intermediate risk (a Gleason score of 7) it nearly always is an intermediate risk. As a result, doctors can make predictions from Gleason grades. The more distorted and aggressive the cancer looks, the higher the Gleason grade, and the more aggressive the cancer behaves in the body.

Understanding how it works

The lowest number on the Gleason grade scale is 1,