Prognostic Effect of Kelim Score of Prostate-Specific Antigen in Hormone-Sensitive Prostate Cancer Patients Treated With Novel Androgen Receptor Inhibitors: Pioneering New Ways

Abstract

Background The prognostic value of the PSA ELIMination rate constant K (PRO-KELIM) score was investigated in patients with metastatic castration-sensitive prostate cancer (mCSPC) treated with novel androgen receptor inhibitors. Methods This multicenter retrospective study included 160 patients diagnosed with prostate adenocarcinoma between 2011 and 2024 who received enzalutamide or abiraterone during the mCSPC and had at least three PSA measurements within the first 100 days of treatment. The patients were categorized into favorable (PRO-KELIM >= 1.0) and unfavorable (PRO-KELIM < 1.0) groups. Progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier survival analysis and Cox regression. Results Median PFS was significantly higher in the favorable group than in the unfavorable group (not reached vs. 40.0 months, p < 0.001). The estimated 2-year PFS rates in the favorable and unfavorable groups were 78% and 52%, respectively. In multivariate analyses, a high PRO-KELIM score (HR 2.99; 95% CI 1.35-6.66, p = 0.007) and good initial response to treatment (p = 0.001) were independent favorable prognostic factors for PFS. The median OS did not differ significantly between the groups (p = 0.27). PRO-KELIM score was not an independent prognostic factor for OS (p = 0.76). Conclusion These findings suggest that the PRO-KELIM score can be a valuable prognostic tool in the mCSPC to assess early treatment response and predict disease progression.