When prostate cancer is suspected, a biopsy of the gland may be recommended by your doctor. The tissue extracted during a biopsy is then examined in a lab by a pathologist, who can determine whether cancerous cells are present in the prostate. These findings are put together in what’s known as a pathology report, and this will show what stage the cancer has reached. To determine the stage of prostate cancer, a Gleason Score of the prostate’s tissue is given between 2 and 10. Based on how cells look under a microscope, the Gleason Score shows the likelihood that the cancer will spread to other areas of the body.

If a low Gleason Score is determined, the abnormal cells still look relatively similar to normal cells. This scenario is ideal for a prostate cancer diagnosis. Should a very high Gleason Score be measured, the chances the cancer will spread are high and the prognosis is generally poor. In a high Gleason Score, the cancerous cells are very different in appearance from that of normal prostate cells. According to the Prostate Cancer Research Institute, the Gleason Score is the most widespread form of prostate cancer tissue grading in use today.