Dean LW, et al. - Authors sought to compare various methods of Gleason pattern 4 (GP4) quantification and assessed their correlation with adverse pathology at radical prostatectomy (RP). Participants were 457 men with GrdGrp 2 prostate cancer on biopsy who subsequently had RP. For patients with Grade group (GrdGrp) 2/GS 3+4=7 prostate cancer, inclusion of Gleason pattern 4 quantification in pathology reports and risk prediction models was supported in the findings. The strongest benefit for prediction of adverse pathology was provided by the total length of GP4 across all cores.