Assessment of 68Ga-PSMA-11 PET Accuracy in Localizing Recurrent Prostate Cancer: A Prospective Single-Arm Clinical Trial.

In retrospective studies, 68Ga-PSMA-11 positron emission tomographic (PET) imaging improves detection of biochemically recurrent prostate cancer compared with conventional imaging.

To assess 68Ga-PSMA-11 PET accuracy in a prospective multicenter trial.

In this single-arm prospective trial conducted at University of California, San Francisco and University of California, Los Angeles, 635 patients with biochemically recurrent prostate cancer after prostatectomy (n = 262, 41%), radiation therapy (n = 169, 27%), or both (n = 204, 32%) underwent 68Ga-PSMA-11 PET. Presence of prostate cancer was recorded by 3 blinded readers on a per-patient and per-region base. Lesions were validated by histopathologic analysis and a composite reference standard.

Endpoints were positive predictive value (PPV), detection rate, interreader reproducibility, and safety.

A total of 635 men were enrolled with a median age of 69 years (range, 44-95 years). On a per-patient basis, PPV was 0.84 (95% CI, 0.75-0.90) by histopathologic validation (primary endpoint, n = 87) and 0.92 (95% CI, 0.88-0.95) by the composite reference standard (n = 217). 68Ga-PSMA-11 PET localized recurrent prostate cancer in 475 of 635 (75%) patients; detection rates significantly increased with prostate-specific antigen (PSA): 38% for <0.5 ng/mL (n = 136), 57% for 0.5 to <1.0 ng/mL (n = 79), 84% for 1.0 to <2.0 ng/mL (n = 89), 86% for 2.0 to <5.0 ng/mL (n = 158), and 97% for ≥5.0 ng/mL (n = 173, P < .001). Interreader reproducibility was substantial (Fleiss κ, 0.65-0.78). There were no serious adverse events associated with 68Ga-PSMA-11 administration. PET-directed focal therapy alone led to a PSA drop of 50% or more in 31 of 39 (80%) patients.

Using blinded reads and independent lesion validation, we establish high PPV for 68Ga-PSMA-11 PET, detection rate and interreader agreement for localization of recurrent prostate cancer. Identifiers: NCT02940262 and NCT03353740.

JAMA oncology. 2019 Mar 28 [Epub ahead of print]

Wolfgang P Fendler, Jeremie Calais, Matthias Eiber, Robert R Flavell, Ashley Mishoe, Felix Y Feng, Hao G Nguyen, Robert E Reiter, Matthew B Rettig, Shozo Okamoto, Louise Emmett, Helle D Zacho, Harun Ilhan, Axel Wetter, Christoph Rischpler, Heiko Schoder, Irene A Burger, Jeannine Gartmann, Raven Smith, Eric J Small, Roger Slavik, Peter R Carroll, Ken Herrmann, Johannes Czernin, Thomas A Hope

Ahmanson Translational Imaging Division, Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles., Departments of Radiology and Biomedical Imaging and Pharmaceutical Chemistry, University of California San Francisco, San Francisco., Department of Urology, University of California San Francisco, San Francisco., Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco., Department of Urology, UCLA Medical Center, University of California Los Angeles, Los Angeles., Department of Radiology, Obihiro Kosei Hospital, Obihiro, Japan., Department of Theranostics and Nuclear Medicine, St Vincent's Hospital, Sydney, Australia., Department of Nuclear Medicine, Aalborg University Hospital, Aalborg, Denmark., Department of Nuclear Medicine, Ludwig-Maximilians-University Munich, Munich, Germany., Department of Diagnostic and Interventional Radiology and Neuroradiology, University of Duisburg-Essen, Essen, Germany., Department of Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany., Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York., Department of Nuclear Medicine, University Hospital Zürich, University of Zürich, Switzerland.