The prognostic value of the CALLY index in patients with metastatic hormone-sensitive prostate cancer.

[BACKGROUND] The C-reactive protein-albumin-lymphocyte index (CALLY), a composite inflammatory and nutritional biomarker, has shown prognostic utility in various cancers, but its role in metastatic hormone-sensitive prostate cancer (mHSPC) remains underexplored.

[OBJECTIVE] To evaluate the association between baseline CALLY index and overall survival (OS) and time to castration-resistant prostate cancer (CRPC) in mHSPC patients.

[METHODS] In this retrospective cohort study, 192 mHSPC patients receiving first-line endocrine therapy (2017-2024) were stratified by median CALLY (30) into low-CALLY (30) and high-CALLY (≥ 30) groups. Inverse probability of treatment weighting (IPTW) was applied to balance baseline covariates. Weighted Cox models assessed associations with OS and CRPC-free survival. Subgroup analyses were conducted by age group, metastatic volume and first-line mHSPC therapy.

[RESULTS] After IPTW adjustment, a high baseline CALLY index was identified as an independent protective factor for both clinical endpoints. Specifically, patients in the high-CALLY group had a 71% reduced risk of all-cause mortality (adjusted hazard ratio [HR] 0.29, 95% confidence interval [CI] 0.18-0.46, p < 0.001) and a 49% reduced risk of CRPC progression (adjusted HR 0.51, 95% CI 0.34-0.77, p = 0.001), compared with the low-CALLY group. The prognostic association remained consistent across all prespecified subgroups, with pronounced benefits observed in patients with high-volume metastatic disease and those receiving first-line bicalutamide. Sensitivity analyses (treating CALLY as a continuous variable, conventional multivariable Cox regression) and E-value assessment further confirmed the robustness and independence of the findings.

[CONCLUSION] The CALLY index is an accessible and independent prognostic biomarker for OS and CRPC progression in mHSPC. Its integration into clinical assessment could enhance risk stratification and support personalized treatment planning, potentially improving long-term patient outcomes.