Prostate-specific membrane-antigen positron emission tomography (PSMA-PET) has transformed management of prostate cancer biochemical recurrence (BCR) with higher diagnostic accuracy than previous imaging modalities. 64Cu-SAR-bisPSMA PET/computed tomography (CT) (64Cu-bisPSMA) is a bivalent-PSMA-peptide with 12.7-hr half-life. The study objective was detection rate (per-patient) comparison between 64Cu-bisPSMA and 68GaPSMA-11 PET/CT (68Ga-PSMA) in BCR post radical prostatectomy (RP) (NCT06907641).
This prospective imaging trial enrolled 50 participants with BCR (PSA 0.2-0.75 ng/ml). 64Cu-bisPSMA (1 and 24 hr) and 68Ga-PSMA were acquired within 3-wk. Images were prospectively reported, and triple read for concordance. Management impact was evaluated after 68Ga-PSMA and 64Cu-bisPSMA. A reference standard (RS) for accuracy included biopsy, targeted treatment response (no androgen deprivation therapy), PSA increase/decrease on observation or repeat imaging (64Cu-bisPSMA). The primary endpoint was mean per-participant lesional difference. Paired t tests and mixed-effects Poisson regression assessed lesion number differences between scans.
Median prostate specific antigen (PSA) was 0.43 (interquartile range: 0.31-0.63). Mean per-participant lesions were higher in 64Cu-bisPSMA (1.26) versus 68GaPSMA (0.48), difference 0.78 (95% CI: 0.52-1.04), ratio 2.63 (95% CI: 1.64-4.20) (p < 0.0001). At a per-participant level 78% (39/50) were positive on 24-hr 64Cu-bisPSMA compared to 36% (18/50) on 68GaPSMA. Management changed between scans in 22/50 (44%). 64Cu-bisPSMA were triple concordant in 84% (42/50) and 68Ga-PSMA reads in 80% (40/50). RS-true positive was 71% (24/34) versus 29% (10/34) and RS-false negative rate was 21% (7/34) versus 65% (22/34) for 64Cu-bisPSMA versus 68Ga-PSMA, respectively.
64Cu-bisPSMA-PET/CT identifies a higher number of disease recurrences than 68Ga PSMA-PET/CT with substantial management impact and a high RS true positive rate in men with BCR post RP.
European urology. 2026 Mar 27 [Epub ahead of print]
Sobia Khan, Nathan Papa, Andrew Kneebone, Thomas Eade, Narjess Ayati, Andrew Nguyen, Keith Wong, Jeff Chen, Bao Ho, Jordan Idiare, George Sidhom, Matthew J Roberts, James Thompson, Shikha Sharma, Shraddha Weir, Katrina Devitt, Raji Kooner, Hester Lieng, Kris Rasiah, Joanna Olphert, Jeremy de Leon, George Hruby, Phillip Stricker, Louise Emmett
Department of Theranostics and Nuclear Medicine, St Vincent's Hospital, Sydney, Australia., Garvan Institute of Medical Research, Sydney, Australia., Department of Radiation Oncology, Royal North Shore Hospital, Sydney, Australia., Department of Theranostics and Nuclear Medicine, St Vincent's Hospital, Sydney, Australia; St Vincent's Clinical School, University of New South Wales, Sydney, Australia., Department of Urology, Royal Brisbane and Women's Hospital, Brisbane, Australia., Department of Urology, St. Vincent's Hospital, Sydney, Australia., Central Coast Cancer Centre, Gosford, New South Wales, Australia., Department of Urology, St George Hospital, Kogarah, NSW, Australia., Genesis Care, St Vincent's Hospital, Darlinghurst, NSW, Australia., Department of Radiation Oncology, Royal North Shore Hospital, Sydney, Australia; Genesis Care, St Vincent's Hospital, Darlinghurst, NSW, Australia., Garvan Institute of Medical Research, Sydney, Australia; St Vincent's Clinical School, University of New South Wales, Sydney, Australia., Department of Theranostics and Nuclear Medicine, St Vincent's Hospital, Sydney, Australia; Garvan Institute of Medical Research, Sydney, Australia; St Vincent's Clinical School, University of New South Wales, Sydney, Australia. Electronic address: .