Impact of Prognostic Nutrition Index and Geriatric Nutritional Risk Index on Prognosis in Elderly Patients with Early-Stage Prostate Cancer

Aim: Prostate cancer is one of the most common malignancies in men, with high survival rates when detected early, where the tumor is confined to the prostate. However, prognostic factors in elderly patients remain insufficiently defined. Malnutrition, linked to cancer prognosis, highlights the growing importance of nutritional and inflammatory status. The Geriatric Nutritional Risk Index (GNRI), based on body weight and serum albumin levels, is a simple tool to assess nutritional status. This study aims to evaluate the prognostic value of the Prognostic Nutritional Index (PNI) and GNRI in elderly patients with early-stage prostate cancer. Methods: This retrospective study included 205 patients aged ≥65 years who were diagnosed with early-stage prostate cancer between 2018 and 2024. Patients with metastatic disease, incomplete data, or a prior malignancy were excluded. Nutritional status was evaluated using the PNI and GNRI, calculated from baseline serum albumin, lymphocyte count, and body weight. Survival outcomes were analyzed using Kaplan–Meier and Cox regression methods. ROC analysis was performed to determine optimal cut-off values for PNI and GNRI. Subgroup analyses were conducted based on age (65-75 and 75-85 years), Gleason score, PSA levels, tumor stage, and radiotherapy status. All statistical analyses were performed using SPSS version 22.0. Results: Among the 205 patients, the median age was 72 years, with 41% aged ≥75. The median PNI and GNRI values were 48.2 and 95.4, respectively. Survival analysis showed that low PNI (< 45) was associated with a median survival of 78 months, while high PNI (≥45) had 115 months (p = 0.015). Similarly, low GNRI (< 92) had a median survival of 74 months, and high GNRI (≥92) had 120 months (p = 0.002). The ROC curve analysis showed AUCs of 0.78 for PNI and 0.84 for GNRI. Subgroup analysis revealed that older age (≥75), Gleason score ≥8, high PSA, and T2 tumor stage were linked to shorter survival. Radiotherapy improved survival (122 vs. 94 months, p = 0.008). Survival decreased with age (65-75 years: 110 months vs. 75-85 years: 85 months, p = 0.005). Gleason score ≥8 and high PSA (≥10 ng/mL) were independent poor prognostic factors (HR = 1.82, p = 0.002). Multivariate analysis confirmed that low PNI and low GNRI were independent risk factors, while radiotherapy, lower PSA, and T1 tumor stage were associated with better outcomes. Conclusion: GNRI and PNI can be considered prognostic markers in elderly patients with early-stage prostate cancer. Advanced age, high Gleason score, and low nutritional indices are associated with a worse prognosis.