Target volume delineations for prostate cancer (PCa) salvage radiotherapy (SRT) after radical prostatectomy are usually drawn in the absence of visibly recurrent disease. 68Ga-labeled prostate-specific membrane antigen (PSMA-11) PET/CT detects recurrent PCa with sensitivity superior to standard-of-care imaging at serum prostate-specific antigen (PSA) values low enough to affect target volume delineations for routine SRT.
Results: The median PSA level at the time of 68Ga-PSMA-11 PET/CT was 0.48 ng/mL (range, 0.03–1 ng/mL). One hundred thirty-two of 270 patients (49%) had a positive 68Ga-PSMA-11 PET/CT result. Fifty-two of 270 (19%) had at least one PSMA-11–positive lesion not covered by the consensus CTVs. Thirty-three of 270 (12%) had extrapelvic PSMA-11–positive lesions, and 19 of 270 (7%) had PSMA-11–positive lesions within the pelvis but not covered by the consensus CTVs. The 2 most common 68Ga-PSMA-11–positive lesion locations outside the consensus CTVs were bone (23/52, 44%) and perirectal lymph nodes (16/52, 31%). Conclusion: Post hoc analysis of 68Ga-PSMA-11 PET/CT implied a major impact on SRT planning in 52 of 270 patients (19%) with PCa early BCR (PSA < 1.0 ng/mL). This finding justifies a randomized imaging trial of SRT with or without 68Ga-PSMA-11 PET/CT investigating its potential benefit on clinical outcome.
J Nucl Med February 1, 2018 vol. 59 no. 2 230-237
Jeremie Calais1, Johannes Czernin1, Minsong Cao2, Amar U. Kishan2, John V. Hegde2, Narek Shaverdian2, Kiri Sandler2, Fang-I Chu2, Chris R. King2, Michael L. Steinberg2, Isabel Rauscher3, Nina-Sophie Schmidt-Hegemann4, Thorsten Poeppel5, Philipp Hetkamp5, Francesco Ceci1, Ken Herrmann1,5, Wolfgang P. Fendler1,6, Matthias Eiber1,3 and Nicholas G. Nickols2,7
1 Ahmanson Translational Imaging Division, Department of Molecular and Medical Pharmacology, UCLA, Los Angeles, California
2 Department of Radiation Oncology, UCLA, Los Angeles, California
3 Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
4 Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
5 Department of Nuclear Medicine, Universitätsklinikum Essen, Essen, Germany
6 Department of Nuclear Medicine, Ludwig-Maximilians-University, Munich, Germany; and
7 Department of Radiation Oncology, VA Greater Los Angeles Healthcare System, Los Angeles, California
PSMA PET/CT Visualizes Prostate Cancer Recurrence Early, Impacts Radiation Therapy