Würnschimmel C, Wenzel M, Chierigo F, et al. - Experts aspired to explore whether Gleason Grade Group (GGG) IV patients treated with radical prostatectomy (RP) or external beam radiotherapy (EBRT) exhibit different cancer-specific mortality (CSM) rates according to underlying Gleason patterns (GP): 4 + 4 vs 3 + 5 vs 5 + 3. All GGG IV patients treated with either RP or EBRT within the Surveillance, Epidemiology, and End Results 2004–2016 database were identified. Of the 26,458 GGG IV patients, 14,203 (53.7%) received EBRT and 12,255 (46.3%) received RP. The presence of biopsy GP 5 + 3 in GGG IV RP candidates indicates a significantly higher CSM than GP 4 + 4 or 3 + 5. There were no significant CSM differences across GGG IV EBRT candidates based on GP.