Accuracy of 68Ga-PSMA PET/CT for lymph node and bone primary staging in prostate cancer

PurposeThe aim of this study is to assess the accuracy of the ⁶⁸Ga-PSMA PET/CT for lymph nodes and bones in the primary stage of prostate cancer.MethodsA total of 126 patients who were submitted to ⁶⁸Ga-PSMA PET/CT from January 2016 to February 2019 for prostate cancer staging, detection of clinically significant lesions or active surveillance were included in this study. All studies were read by 2 experienced physicians (a nuclear physician and a radiologist). The reports were made in consensus and used by one of the authors to classify the exam in positive or negative. We evaluated presence of abnormal uptake in the prostate, lymph nodes, and bone. The reference standards were histopathological confirmation, confirmatory imaging exams and/or clinical follow-up showing lesion(s) regression after specific treatment, or typical osseous metastatic lesions and highly increased PSA levels.ResultsMeasurement of diagnostic performance indicated a sensitivity, specificity and accuracy of 75%, 96.3%, and 90.8%, respectively, for lymph node involvement, and 90.9%, 50%, and 76.5%, respectively for metastatic bone lesions.ConclusionThis study showed high specificity and accuracy of ⁶⁸Ga-PSMA PET/CT for lymph node and bone involvement in prostate cancer staging.