Prognostic value of quantitative PSMA-PET parameters during chemotherapy in prostate cancer.

• DOI: 10.1200/jco.2025.43.5_suppl.33
• Publication Date: 2025-02-18T14:32:56Z
• Authors: Stephan Skawran; Andrei Gafita; Theo Lorenzini; Sebastian Hoberück; Francesco Mattana; Andrea Di Giorgio; Matthias Miederer; Channing Judith P...; Loic Djaileb; Lilja B Solnes; Andrea Farolfi; Francesco Ceci; Matthias Eiber; Andrew F Voter
• Keywords: Value (mathematics)

33 Background: PSMA-PET/CT is increasingly being used to monitor chemotherapy in prostate cancer and shows promise for predicting outcomes improving response evaluation. This retrospective study aimed determine the prognostic value of quantitative tumor burden parameters derived from overall survival (OS) during taxane-based chemotherapy. Methods: Databases 6 institutions were screened patients who underwent[ 68 Ga]Ga-PSMA11-PET serum PSA measurements at baseline within three months after last taxane based dose. Tumor segmentation was performed using DeepPSMA software PSMA-PET whole-body obtained: PSMA-positive volume (PSMA-VOL) maximum/average standardized uptake (SUV max , SUV mean ). Univariate Cox-regression analyses by hazard ratio (HR) with 95% confidence interval (CI) evaluate association PSMA levels OS. Harrell’s concordance index (C-index) accuracy. Optimal cut points determined maximizing log-rank statistic. Results: A total 128 included, whom 62/128 (48%) had castration-sensitive 66/128 (52%) castration-resistant cancer. At baseline, PSMA-VOL numerically reached highest OS (C-index: 0.88) followed 0.80, p = 0.85), while percentage change treatment 0.94) significantly higher than 0.85, 0.02), (complete data shown Table 1). Conclusions: Baseline post-therapeutic are OS, changes outperformed treatment. Parameter Cut point HR (95% CI) P-value C-index vol > 28 ml 5.59 (2.77 – 11.27) < 0.001 0.88 (0.81 0.96) 13.2 2.00 (0.96 4.15) 0.06 0.29 (0.13 0.45) 71 2.18 (1.23 3.86) 0.007 0.69 (0.57 0.82) PSA, 3.9 ng/ml 3.53 (1.75 7.13) 0.80 (0.69 0.92) relative -21 % 4.48 (2.80 7.17) 0.85 (0.78 0.91) -70 2.42 (1.50 3.82) 0.76 (0.67 0.86) -44 5.98 (2.57 13.88) (0.73 0.98) -97 7.03 (3.20 15.43) 0.94 (0.88 0.99)