Clinicopathologic Predictors of PSMA-PET Detection, Recurrence Pattern, and Biochemical Outcome Following Salvage Radiotherapy After Radical Prostatectomy
- 1Advanced Molecular Imaging in Radiotherapy (AdMIRe) Research Laboratory, Purdue University, West Lafayette, IN, USA; Department of Radiation Oncology, Indiana
Abstract
PurposeBiochemical recurrence (BCR) after radical prostatectomy (RP) presents heterogeneous recurrence patterns and variable outcomes following salvage radiotherapy (sRT). We evaluated clinicopathologic determinants of PSMA-PET/CT detection, anatomical recurrence distribution, and biochemical disease-free survival (bDFS) following PSMA-PET-guided sRT.
MethodsThis retrospective single-institution study included 140 patients with BCR after RP who underwent 68Ga-PSMA-PET/CT prior to sRT with or without androgen deprivation therapy. PSMA-PET-positive findings were categorized as prostate bed only (PBO) or pelvic nodal involvement with or without the prostate bed (PLNI). Receiver operating characteristic (ROC) analysis, logistic regression, and Cox proportional hazards models were employed.
ResultsPSMA-PET detected locoregional recurrence in 77/140 patients (55%). On multivariable analysis, PSA at recurrence (OR=2.07; p=0.003) and age (OR=1.07; p=0.016) were the sole independent predictors of PSMA-PET positivity. ROC analysis yielded AUC=0.74 (optimal threshold of 0.58 ng/mL). Among PSMA-positive patients, PBO was associated with a longer time to BCR (tBCR) (37.5 versus 15 months; p=0.006). Seminal vesicle invasion (SVI) and pT-stage predicted PLNI on univariable analysis. Among 124 of 140 evaluable patients (median follow-up 31 months), estimated bDFS at 24, 36, and 60 months was 89.7%, 80.2%, and 54.1%, respectively. SVI (HR=2.39; p=0.031), EPE (HR=2.82; p=0.012), pT-stage (HR=1.64; p=0.021), and pN-stage (HR=1.83; p=0.045) were associated with increased failure on univariable Cox regression, though none retained independent significance.
ConclusionPSA burden and age independently predicted PSMA-PET detection. Recurrence patterns reflected disease behavior, as PBO was associated with longer tBCR. Adverse pathologic features were associated with pelvic nodal disease and reduced biochemical control; none remained independently predictive.
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BibTeX
@misc{jubril2026clinicopathologic,
title = {{Clinicopathologic Predictors of PSMA-PET Detection, Recurrence Pattern, and Biochemical Outcome Following Salvage Radiotherapy After Radical Prostatectomy}},
author = {R. Jubril and A. V. Prabhu and O. Ishaq and J. A. Ocana and M. Tann and C. Njeh and C. D. Bahler and J. Holmes and O. Oderinde},
howpublished = {medRxiv},
year = {2026},
month = oct,
doi = {10.64898/2026.10.16.26365643},
url = {https://www.medrxiv.org/content/10.64898/2026.10.16.26365643v1},
note = {CC BY-NC-ND},
}
RIS
TY - UNPB
TI - Clinicopathologic Predictors of PSMA-PET Detection, Recurrence Pattern, and Biochemical Outcome Following Salvage Radiotherapy After Radical Prostatectomy
AU - R. Jubril
AU - A. V. Prabhu
AU - O. Ishaq
AU - J. A. Ocana
AU - M. Tann
AU - C. Njeh
AU - C. D. Bahler
AU - J. Holmes
AU - O. Oderinde
PY - 2026
DA - 2026/10/16
PB - medRxiv
DO - 10.64898/2026.10.16.26365643
UR - https://www.medrxiv.org/content/10.64898/2026.10.16.26365643v1
AB - PurposeBiochemical recurrence (BCR) after radical prostatectomy (RP) presents heterogeneous recurrence patterns and variable outcomes following salvage radiotherapy (sRT). We evaluated clinicopathologic determinants of PSMA-PET/CT detection, anatomical recurrence distribution, and biochemical disease-free survival (bDFS) following PSMA-PET-guided sRT. MethodsThis retrospective single-institution study included 140 patients with BCR after RP who underwent 68Ga-PSMA-PET/CT prior to sRT with or without androgen deprivation therapy. PSMA-PET-positive findings were categorized as prostate bed only (PBO) or pelvic nodal involvement with or without the prostate bed (PLNI). Receiver operating characteristic (ROC) analysis, logistic regression, and Cox proportional hazards models were employed. ResultsPSMA-PET detected locoregional recurrence in 77/140 patients (55%). On multivariable analysis, PSA at recurrence (OR=2.07; p=0.003) and age (OR=1.07; p=0.016) were the sole independent predictors of PSMA-PET positivity. ROC analysis yielded AUC=0.74 (optimal threshold of 0.58 ng/mL). Among PSMA-positive patients, PBO was associated with a longer time to BCR (tBCR) (37.5 versus 15 months; p=0.006). Seminal vesicle invasion (SVI) and pT-stage predicted PLNI on univariable analysis. Among 124 of 140 evaluable patients (median follow-up 31 months), estimated bDFS at 24, 36, and 60 months was 89.7%, 80.2%, and 54.1%, respectively. SVI (HR=2.39; p=0.031), EPE (HR=2.82; p=0.012), pT-stage (HR=1.64; p=0.021), and pN-stage (HR=1.83; p=0.045) were associated with increased failure on univariable Cox regression, though none retained independent significance. ConclusionPSA burden and age independently predicted PSMA-PET detection. Recurrence patterns reflected disease behavior, as PBO was associated with longer tBCR. Adverse pathologic features were associated with pelvic nodal disease and reduced biochemical control; none remained independently predictive.
ER -