Prognostic Nutritional Index and a Blood-Based Prognostic Tool in Prostate Cancer Treated with Abiraterone, Enzalutamide or Cabazitaxel.

Background and

Objectives

The prognostic nutritional index (PNI), a marker reflecting both nutritional and immune status, has been associated with prognosis in various malignancies. However, evidence in metastatic castration-resistant prostate cancer (mCRPC), particularly from non-Asian populations, remains limited. This study aimed to evaluate the prognostic value of baseline PNI and to develop a blood-based prognostic model in mCRPC patients treated with abiraterone acetate (AA), enzalutamide (ENZA), or cabazitaxel (CABA). Materials and

Methods

This retrospective study included mCRPC patients treated with AA, ENZA, or CABA before or after docetaxel. PNI was calculated as: 10 × serum albumin (g/dL) + 0.005 × total lymphocyte count (/mm3). Patients were classified into low-PNI (≤40.8) and high-PNI (>40.8) groups using the median PNI value. Survival outcomes were analyzed using Kaplan-Meier and Cox regression methods.

Results

A total of 299 patients were analyzed: 133 (44.5%) received AA, 106 (35.5%) ENZA, and 60 (20.0%) CABA. Patients with high PNI had significantly longer median overall survival (OS; 30.2 vs. 12.6 months, p < 0.001), radiologic progression-free survival (rPFS; 13.5 vs. 6.7 months, p < 0.001), and PSA progression-free survival (PSA-PFS; 10.2 vs. 5.1 months, p < 0.001). These associations remained significant across all treatment subgroups. In multivariate analysis, prostate surgery (HR: 0.6), high PNI (HR: 0.5), PSA response (HR: 0.5), and elevated ALP (HR: 1.6) were independent predictors of OS. A prognostic model incorporating PNI, alkaline phosphatase, and anemia stratified patients into four risk groups with distinct OS: 49.1, 30.8, 18.8, and 9.1 months, respectively.

Conclusions

This is the largest study to date in a non-Asian mCRPC population showing that baseline PNI is a strong, independent prognostic factor for survival. The proposed blood-based tool may aid in clinical risk stratification, pending prospective validation.