3DCT, 3D conformal radiotherapy; ACE-27, Adult Comorbidity Evaluation 27; AD, Alzheimer's disease; ADT, androgen deprivation therapy; ASCO, American Society of Clinical Oncology; Androgen deprivation therapy; BRFS, biochemical relapse-free survival; BT, brachytherapy; Brachytherapy; CCI, Charlson comorbidity index; EBRT, External beam radiation therapy; Elderly; G, grade; GI, Gastro-intestinal; GI, Genito-urinary; HDR, high dose-rate; IGRT, Image Guided Radiation Therapy; IMRT, intensity modulated radiation therapy; LDR, low dose-rate; LE, life expectancy; MA, median age; MFU, median follow-up; NCCN, National Comprehensive Cancer Network; OS, overall survival; PC, prostate cancer; PCSM, prostate cancer specific mortality; PCSS, Prostate cancer specific survival; Prostate cancer; QoL, quality of life; Radiation therapy; SBRT, stereotactic body radiation therapy; SEER, Surveillance, Epidemiology, and End Results; SIOG, International Society of Geriatric Oncology; bNED, Biological non-evidence of disease