This new scoring system was accepted by the World Health Organization (WHO) in 2016: Grade group 1 = Gleason 3 + 3 Grade group 2 = Gleason 3 + 4 Grade group 3 = Gleason 4 + 3 Grade group 4 = Gleason 8 Grade group 5 = Gleason 9 and 10 Gleason grade group, clinical stage, and PSA level together (using tables or nomograms) predict pathologic stage and prognosis better than any of them alone.