TY - JOUR
T1 - External Validation of Two Nomograms Developed for 68Ga-PSMA-11 Applied to the Prostate-specific Membrane Antigen Tracer 18F-DCFPyl
T2 - Is Prediction of the Optimal Timing of Salvage Therapy Feasible?
AU - Luiting, Henk B.
AU - Remmers, Sebastiaan
AU - Meijer, Dennie
AU - Vis, André N.
AU - Donswijk, Maarten
AU - Oprea-Lager, Daniela E.
AU - Emmett, Louise
AU - Rauscher, Isabel
AU - Van der Poel, Henk G.
AU - Roobol, Monique J.
AU - van Leeuwen, Pim J.
N1 - Publisher Copyright:
© 2021 The Authors
PY - 2021/6
Y1 - 2021/6
N2 - Two nomograms have been developed to predict the outcome of positron emission tomography (PET)/computed tomography (CT) imaging with68Ga-labeled ligands for prostate-specific membrane antigen (68Ga-PSMA) for patients with rising prostate-specific antigen after radical prostatectomy (RP). These nomograms quantify the ability of PSMA PET/CT to detect prostate cancer recurrences, and therefore provide critical information in determining the optimal timing for PSMA PET/CT in guiding salvage therapies. We validated the ability of these nomograms to accurately predict PET/CT outcome using another ligand tracer, 18F-DCFPyL. The external validation cohort consisted of 157 men from the Prostate Cancer Network Netherlands who underwent 18F-DCFPyL PET/CT to guide salvage therapies after RP. The nomogram of Rauscher et al (predicting a positive scan) showed accurate prediction of 50–80% (discrimination 0.68, 95% confidence interval [CI] 0.59–0.76). The nomogram of Luiting et al (predicting recurrence outside the prostatic fossa) showed accurate prediction for predicted probability values between 15% and 65%, with a small degree of overestimation for predicted probability values between 30% and 50% (discrimination 0.74, 95% CI 0.28–1.24). According to calibration curves, discrimination results, and decision curve analysis, we conclude that clinicians can use these 68Ga-PSMA–based nomograms to predict 18F-DCFPyL PET/CT outcome. These nomograms improve shared decision-making in determining the optimal time to initiate PSMA PET/CT–guided salvage therapies. Patient summary: Prediction tools developed for prostate scans (positron emission tomography, PET) using one type of radioactive tracer (chemicals labeled with gallium-68) are also accurate in predicting scan findings with another tracer (a chemical labeled with fluorine-18). Our study confirms that these tools can be used to guide decisions on the timing of treatments for prostate cancer recurrence.
AB - Two nomograms have been developed to predict the outcome of positron emission tomography (PET)/computed tomography (CT) imaging with68Ga-labeled ligands for prostate-specific membrane antigen (68Ga-PSMA) for patients with rising prostate-specific antigen after radical prostatectomy (RP). These nomograms quantify the ability of PSMA PET/CT to detect prostate cancer recurrences, and therefore provide critical information in determining the optimal timing for PSMA PET/CT in guiding salvage therapies. We validated the ability of these nomograms to accurately predict PET/CT outcome using another ligand tracer, 18F-DCFPyL. The external validation cohort consisted of 157 men from the Prostate Cancer Network Netherlands who underwent 18F-DCFPyL PET/CT to guide salvage therapies after RP. The nomogram of Rauscher et al (predicting a positive scan) showed accurate prediction of 50–80% (discrimination 0.68, 95% confidence interval [CI] 0.59–0.76). The nomogram of Luiting et al (predicting recurrence outside the prostatic fossa) showed accurate prediction for predicted probability values between 15% and 65%, with a small degree of overestimation for predicted probability values between 30% and 50% (discrimination 0.74, 95% CI 0.28–1.24). According to calibration curves, discrimination results, and decision curve analysis, we conclude that clinicians can use these 68Ga-PSMA–based nomograms to predict 18F-DCFPyL PET/CT outcome. These nomograms improve shared decision-making in determining the optimal time to initiate PSMA PET/CT–guided salvage therapies. Patient summary: Prediction tools developed for prostate scans (positron emission tomography, PET) using one type of radioactive tracer (chemicals labeled with gallium-68) are also accurate in predicting scan findings with another tracer (a chemical labeled with fluorine-18). Our study confirms that these tools can be used to guide decisions on the timing of treatments for prostate cancer recurrence.
UR - http://www.scopus.com/inward/record.url?scp=85105290024&partnerID=8YFLogxK
U2 - 10.1016/j.euros.2021.04.002
DO - 10.1016/j.euros.2021.04.002
M3 - Article
AN - SCOPUS:85105290024
SN - 2666-1691
VL - 28
SP - 47
EP - 51
JO - European Urology Open Science
JF - European Urology Open Science
ER -