European Registry of Next Generation Imaging in Advanced Prostate Cancer (RING): protocol for an international, prospective registry study.

[INTRODUCTION] Next-generation imaging (NGI), particularly with prostate-specific membrane antigen positron emission tomography (PSMA PET) tracers, enables earlier and more accurate detection of metastases. However, conventional imaging (CT and bone scan) remains more affordable and widely accessible and was the standard used in most pivotal trials that established current survival outcomes. As PSMA PET becomes more widely adopted, a stage migration effect is emerging. However, key uncertainties persist regarding the actual proportional employment of NGI in clinical practice, main indications for its use and the mid-term and long-term effects of an NGI-driven treatment pathway. Furthermore, when or whether CI alone might remain enough informative for the treatment decision-making is still unclear.

[METHODS AND ANALYSIS] The European Registry of Next-Generation Imaging in Advanced Prostate Cancer is a non-profit, non-interventional, multi-centre, international, prospective, investigator-initiated registry that is intended to collect real-world data on how patients with prostate cancer at risk of harbouring metastasis (high-risk at initial diagnosis, or after primary treatment) are managed according to the type of imaging used for the systemic work-up. The registry is conducted in two phases: (1) cross-sectional analysis of imaging choices and their effect on clinical decision-making and (2) longitudinal follow-up evaluating survival outcomes such as progression-free survival (PFS), disease-specific survival (DSS) and skeletal-related events (SSEs). Statistical analyses will include descriptive analysis of demographic and clinical variables, comparative analysis between different imaging pathways, survival and prognostic analyses using Kaplan-Meier tests. The expected minimum sample size of the registry is 600 patients, and the planned follow-up duration is 24 months for the longitudinal follow-up.

[ETHICS AND DISSEMINATION] The study protocol was approved by the ethics committee of Fundació Puigvert (#C2024/30), and ethics approval is required at all participating sites. All patients will provide written informed consent. The results will be disseminated widely and transparently to maximise their effect on clinical practice, research and patient care through peer-reviewed publications, presentations at international conferences as well as through patient advocacy groups and relevant patient websites.

[TRIAL REGISTRATION NUMBER] NCT06866782.