Efficacy of 68Ga-PSMA PET/CT-derived whole-body volumetric parameters in predicting response to second-generation androgen receptor axis-targeted therapy, and the prognosis in metastatic hormone-refractory prostate cancer patients

OpenAlex İngilizce

INTRODUCTION: The present study investigates the role of 68Ga-PSMA PET/CT-derived whole-body metabolic and volumetric parameters in the prediction of treatment response and prognosis among metastatic hormone-refractory prostate cancer patients undergoing second-generation androgen receptor axis-targeted therapy (abiraterone or enzalutamide). MATERIALS AND METHODS: This retrospective study included 44 metastatic hormone-refractory prostate cancer patients undergoing 68Ga-PSMA PET/CT, including 29 enzalutamide-treated and 15 abiraterone-treated patients. RESULTS: Of the 44 patients included in the study, 29 received enzalutamide and 15 received abiraterone. During treatment, the changes in PET parameters were correlated with the PSA (biochemical) response. More specifically, a positive correlation was noted between PSA response and percent change in TLP (ΔTLP) response, and there was concordance between the results (r = 0.652, k = 0.42, P < 0.001). Baseline PSA (P =0.05), high MTVw (P = 0.005), the increase in ΔPSA (P = 0.036), ΔTLP (P = 0.039) and percent change in MTV (ΔMTV) (P = 0.049) values were identified as factors associated with mortality risk.Multivariate analysis showed that PSA1 [odds ratio (OR): 1.005, 95% confidence interval (CI) 1.002-1.008, P = 0.004], ΔPSA (OR: 14.7, 95% CI 1.50-143.7, P = 0.02) and MTVw1 (OR: 11.4, 95% CI 1.11-116, 6, P = 0.04) were independent prognostic factors associated with mortality risk. CONCLUSION: A statistically significant concordance and correlation was noted between 68Ga-PSMA PET/CT-derived whole-body metabolic parameters (ΔTLP and ΔMTV) and ΔPSA. In addition, the baseline PSA, ΔPSA, ΔTLP, ΔMTV and TMTV were identified as predictive factors for mortality risk.