Bone Health and Body Composition as Predictive and Prognostic Markers in Metastatic Castration-resistant Prostate Cancer: A Meet-URO Narrative Review.

Metastatic castration-resistant prostate cancer (mCRPC) presents several challenges, including identifying predictive and prognostic markers for available therapies in order to guide the best clinical choice. Alongside well-known markers such as prostate specific antigen, researchers are trying to understand the role of bone health assessment and body composition in this context. Bone turnover markers, measurable in blood or urine, provide insights into bone formation and resorption dynamics, while body composition metrics derived from radiological imaging (e.g., CT or MRI) can quantify muscle mass, fat distribution, and obesity-related parameters. This narrative review examines current evidence on the relationship between bone health, body composition, and clinical outcomes in mCRPC. We synthesize findings from recent studies evaluating their association with treatment response, adverse event profiles, and survival, highlighting potential mechanisms linking skeletal and metabolic status with disease progression. Although preliminary data suggest that selected bone and body composition markers may inform risk stratification and therapeutic decision-making, evidence remains heterogeneous and largely derived from retrospective or small prospective cohorts. Standardization of measurement methods and thresholds is lacking, limiting their immediate clinical application. Future prospective trials incorporating these parameters as secondary endpoints are warranted to clarify their independent prognostic value and predictive utility. A better understanding of these markers could support more personalized treatment strategies, improve monitoring of therapy-related toxicities, and ultimately enhance both survival and quality of life in patients with mCRPC.