GNRH1 and Familial prostate cancer: <h4>Background</h4>We investigated patterns of gonadotropin-releasing hormone (GnRH) analogue use in castration-resistant prostate cancer (CRPC) using real-world data from six countries.<h4>Patients and methods</h4>Data were obtained from Guy's and St Thomas' NHS Foundation Trust (GSTT, UK), Prostate Cancer data Base Sweden (PCBaSe RAPID 2019, Sweden), Système National Des Données De Santé (SNDS, France), European Institute of Oncology (IEO, Italy), Ghent University Hospital (GUH, Belgium), and American University of Beirut Medical Center (AUB, Lebanon).