New Cancer Safari

Prostate cancer molecular classification more accurate than Gleason score

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) The Gleason Grading system is used to predict the course of prostate cancer. The higher the score, the poorer the prognosis. A newly devised system may be a better crystal ball than this system.

Researchers have developed a method to detect aggressive prostate cancers that appears to be better and more accurate than the Gleason grading system. This new method pinpoints cancers that were missed with Gleason scoring.

"Gleason scores aren't fool-proof."

While the Gleason system is currently the best way to predict the course of prostate cancer, a number of men with low scores do go on to develop aggressive cancers.

Using data from a 2010 Swedish study, Arnold Levine, Ph.D., Professor at the Institute for Advanced Study in Princeton, New Jersey, and colleagues compared 281 prostate cancers utilizing a technique called microarray analysis. This technology measures the expression of huge numbers of genes simultaneously.

The authors identified gene expression signatures relating to a variety of tumor characteristics. The researchers then examined a combination of signatures that appeared in each patient's sample.

With this approach, authors were able to categorize patients from the Swedish study into five prostate cancer subtypes, each of which had a distinct predicted outcome.

Authors found that two of their high-risk categories had a number of men with poor prognoses even though they had low Gleason score tumors.

Findings from this study may one day help physicians accurately predict prognosis at the time a man is initially diagnosed with prostate cancer.

This study was published November 28, 2011 in the Proceedings of the National Academy of Sciences.

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Review Date: 
November 28, 2011
Last Updated:
November 28, 2011