De Laere B, et al. - Assuming that all patients may eventually display perturbed androgen receptor (AR) biomarker output when undergoing long-term chemical castration, alongside the cancer treatment trajectory, researchers suggest the necessity for performing multiple biomarker assessments of AR to identify AR signaling inhibitors (ARSis)-sensitive patients.Patients with metastatic castration-resistant prostate cancer (mCRPC) show poorer outcomes on the ARSis, abiraterone or enzalutamide, in correlation to AR molecular perturbations in liquid biopsy specimens (circulating tumor cells [CTCs] and circulating tumor DNA [ctDNA]), with contradictory claims regarding the clinical use of AR splice variant 7 (AR-V7) or AR amplification status. As per their previous work, the prognostic value of AR perturbations was lost after adjusting for tumor burden estimates and clinical variables. In line with others’ findings, TP53 alterations outperformed AR-driven biomarkers, noting relevant AR-driven biomarkers in 71.3% and 97.9% of patients at baseline and progression, respectively.