PSA response is a key prognostic tool in metastatic hormone-sensitive prostate cancer (mHSPC). Data from SWOG 9346 and TITAN post-hoc analyses demonstrated the prognostic value of PSA thresholds at 6-7 months after androgen deprivation therapy (ADT) or ADT plus apalutamide.
However, variability in thresholds and timing highlights the need to explore PSA kinetics in real-world cohorts. This study investigates PSA dynamics and their predictors following Androgen Receptor Signaling Inhibitors (ARSI) initiation.
This multicenter study included mHSPC patients treated with ADT+ARSI between June 2017 and October 2024. Exclusions included ADT monotherapy, triplet therapy, or ARSI initiation >6 months post-ADT. PSA kinetics were analyzed over 12 months, focusing on SWOG (0.2-4 ng/ml) and TITAN (0.02-0.2 ng/ml) thresholds. Logistic regression and SHAP (SHapley Additive exPlanations) analysis identified predictors of achieving low (<0.2 ng/ml) or ultralow (<0.02 ng/ml) PSA at 6 months.
Among 586 mHSPC patients (median follow-up: 23 months), most had synchronous (58%), low-volume (58%), and ISUP grade 4-5 (64%) disease. At 6 months, 74%, 19%, and 7% achieved PSA <0.2 ng/ml, 0.2-4 ng/ml, and >4 ng/ml (SWOG cutoffs), while 36%, 35%, and 29% achieved PSA <0.02 ng/ml, 0.02-0.2 ng/ml, and >0.2 ng/ml (TITAN cutoffs). Baseline PSA <50 ng/ml and metachronous disease were strong predictors of ultralow PSA.
SWOG and TITAN thresholds offer distinct PSA stratifications, with SWOG grouping more patients into the lowest PSA category and TITAN providing a more balanced distribution. Baseline PSA and metachronous disease are key predictors of favorable PSA responses, emphasizing their importance in guiding management.
Urologic oncology. 2025 May 28 [Epub ahead of print]
Rocío Martínez-Corral, Pedro De Pablos-Rodríguez, Celia Bardella-Altarriba, Francisco Javier Vera-Ballesteros, Arnau Abella-Serra, Victor Rodríguez-Part, María Elena Martínez-Corral, Natalia Picola-Brau, Alicia López-Abad, Álvaro Gómez-Ferrer, Manuel Beamud-Cortés, José Francisco Suárez-Novo, Pedro Ángel López-González, Mireia García-Puche, Ana María Álvarez-Gracia, Daniel Pérez-Fentes
Department of Urology, Complejo Hospitalario Universitario de Santiago de Compostela, University of Santiago de Compostela, Spain., Department of Urology, Instituto Valenciano de Oncología, Valencia, Spain. Electronic address: ., Department of Urology, Hospital de Bellvitge, Barcelona, Spain., Department of Urology, Hospital Virgen de la Arrixaca, Murcia, Spain., Department of Urology, Hospital Universitari Germans Trias i Pujol, Barcelona, Spain., Department of Urology, Instituto Valenciano de Oncología, Valencia, Spain., Department of Radiation Oncology, Institut Català de Oncologia, Barcelona, Spain.
PubMed http://www.ncbi.nlm.nih.gov/pubmed/40441949