Outcomes of Primary Lymph Node Staging of Intermediate and High Risk Prostate Cancer with 68 Ga-PSMA Positron Emission Tomography/Computerized Tomography Compared to Histological Correlation of Pelvic Lymph Node Pathology

PURPOSE: Ga-PSMA (prostate specific membrane antigen) positron emission tomography/computerized tomography to predict histological metastasis on pelvic lymph node dissection performed during radical prostatectomy. MATERIALS AND METHODS: Ga-PSMA positron emission tomography/computerized tomography to identify histological lymph node metastasis in 208 consecutive men who subsequently proceeded with pelvic lymph node dissection at radical prostatectomy. RESULTS: Ga-PSMA imaging 34 had metastasis on histology for 80.8% negative predictive value. Specificity was 93.5% and positive predictive value was 67.7%. For the 172 histologically identified malignant lymph node metastases the sensitivity per node was 24.4% and specificity was 99.5%. CONCLUSIONS: Ga-PSMA positron emission tomography/computerized tomography has poor sensitivity per node to detect all histologically positive lymph node metastases. Thus, pelvic lymph node dissection remains the gold standard to stage pelvic lymph nodes despite its known limitations and complications.