Relating Gleason Scores to Prostate Cancer Tests

by Melinda Beck | The Wall Street Journal | 07.20.2010

Q. Your June 29 article on tests that could predict whether prostate cancers will metastasize was good news. But you never mentioned Gleason scores. How do they relate to these new findings?

—G.O.

A. Gleason scores are one of the tools doctors currently use to evaluate prostate tumors.

After a biopsy, a pathologist evaluates the pattern of abnormal cells in the tumor sample and rates them on a scale of 1 to 5. Gleasons are the sum of two scores, representing the first and second most-common pattern seen.

The lowest possible Gleason score is 2 (1+1), indicating few cancerous changes are present; the highest is 10 (5+5), meaning the cancer is advanced.

Most Gleason scores fall in the middle; and some men with low Gleason scores have cancer that spreads quickly, while some with high scores don't. It's also a single snapshot fixed in time.

The new tests would let researchers read a tumor's DNA makeup like a bar code and identify which genetic changes are associated with highly virulent cancers, allowing them to estimate much more precisely how a tumor might behave.

Copyright The Wall Street Journal 2010