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The Gleason rating scale is a medical diagnosis tool used to determine the severity of male prostate cancer. The numbers on this scale represent the severity of the prostate cancer.

Detemining the Gleason Score

A pathologist assigns a Gleason score based on a study of cancerous cells obtained from a prostate biopsy. The pathologist will observe the patterns of the cancerous cells in comparison to the healthy prostate cells. After observing the most predominant pattern of the cells the pathologist will assign a number between 1 and 5. He will then observe the second most common patter and assign a number between 1 and 5. These number are added together to assign a Gleason score between 2 and 10.

Gleason Score

Gleason scores label the severity and stage of the prostate cancer. Scores of 5 through 7 represent the most common prostate cancers, while scores of 8 or more represent aggressive prostate cancers. Scores under 4 are very rare.

Gleason Score of 8

A Gleason score of 8 represents the least severe cases of aggressive prostate cancer. While this is not the most aggressive form of prostate cancer, it is cause for immediate medical treatment and potentially a prostatectomy.