287 Background: Preserving quality of life (QoL) is an important therapeutic aim in advanced prostate cancer (PCa). The effects of treatment on QoL were studied in a non-interventional study performed from 2010 until 2012 evaluating 1 year of treatment with a LHRH agonist, triptorelin pamoate 6-month depot (TP 6M). Methods: Data of 564 patients with advanced PCa treates in 129 German urology outpatient clinics were analysed. Data on QoL were collected by EORTC questionnaires (QLQ-C30 and -PR25) at baseline, 6 months and 12 months. The QLQ-C30 assesses functional QoL, global health and symptoms of disease, the QLQ-PR25 covers PCa specific symptoms and sexual activity. A clinically relevant improvement, i.e. increase of ≥10 points in the QLQ-C30 global health status/QoL scale, defined treatment responders. Response at month 6 compared to baseline was the primary study endpoint. Results: GlobalHealth Related (HR) QoL was similar over the 1 year follow-up period with a mean (± SD) score of 60.9 (±21.8) at baseline and 61.7 (±22.2) at 12 months. Within the first 6 months, 24.0% of patients were identified as responders (i.e. a clinically relevant improvement in this parameter of ≥10 points). The responder rate was maintained at 12 months of treatment (25.5%). This trend in QoL was also seen in the QLQ-C30 subscales, which were generally similar over the study period. QLQ-PR25 scores were also found to be similar over 1 year, although some deterioration was reported by sexually active patients, as expected. Subgroup analyses on response rates identified age, risk group, pretreatment for PCa and baseline QoL scores as predictors of change in QoL. Conclusions: Treatment with TP 6M over 12 months is associated with few changes in HRQoL and might lead in some patients to clinically meaningful improvements of HRQoL.