what does the gleason score mean
Although most often the Gleason score is based on the 2 areas that make up most of the cancer, there are some exceptions when on a core sample there is either a lot of high-grade cancer or there are 3 grades including high-grade cancer.rades 1 and 2 are not often used for biopsies â most biopsy samples are grade 3 or higher. 1  If the cancerous tissue looks much like normal prostate tissue, a grade of 1 is assigned. 2  If the cancer cells and their growth patterns look very abnormal, a grade of 5 is assigned.