RT Journal Article
SR Electronic
T1 Exploring the Flare Phenomenon in Patients with Castration-Resistant Prostate Cancer: Enzalutamide-Induced PSMA Upregulation Observed on PSMA PET
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 373
OP 376
DO 10.2967/jnumed.124.268340
VO 66
IS 3
A1 van der Gaag, Suzanne
A1 Vis, André N.
A1 Bartelink, Imke H.
A1 Koppes, Josephina C.C.
A1 Hodolic, Marina
A1 Hendrikse, Harry
A1 Oprea-Lager, Daniela E.
YR 2025
UL http://jnm.snmjournals.org/content/66/3/373.abstract
AB Androgen receptor–targeting agents, particularly enzalutamide, show promise in enhancing prostate cancer diagnostic and therapeutic strategies by modulating prostate-specific membrane antigen (PSMA). Methods: A retrospective clinical cohort study investigated 9 men with metastatic castration-resistant prostate cancer on enzalutamide. PSMA PET/CT scans were obtained before and after enzalutamide initiation to assess PSMA expression changes. Lesions and organs at risk were evaluated visually and semiquantitatively. The flare phenomenon was characterized by a significant increase (≥20%) in the SUVmax of existing lesions or the appearance of new PSMA-positive lesions. Results: Exposure to enzalutamide led to a significant PSMA expression increase in 56% of assessed lesions (n = 42), with new lesions detected in 1 patient (11%). PSMA expression in organs at risk remained largely unaffected, indicating a tumor-specific response. Conclusion: Enzalutamide induces PSMA upregulation in metastatic castration-resistant prostate cancer, potentially enhancing diagnostic and therapeutic strategies. Further exploration of the flare phenomenon’s clinical implications is warranted.