RT Journal Article SR Electronic T1 68Ga-PSMA Ligand PET/CT-based Radiotherapy for Lymph Node Relapse of Prostate Cancer After Primary Therapy Delays Initiation of Systemic Therapy JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 1273 OP 1279 VO 37 IS 3 A1 CHRISTOPH HENKENBERENS A1 CHRISTOPH A. VON KLOT A1 TOBIAS L. ROSS A1 FRANK M. BENGEL A1 HANS-JÜRGEN WESTER A1 KATJA HÜPER A1 HANS CHRISTIANSEN A1 THORSTEN DERLIN YR 2017 UL http://ar.iiarjournals.org/content/37/3/1273.abstract AB Aim: To evaluate 68Ga-PSMA ligand positron-emission tomography–computed tomography (PET/CT)-based radiotherapy for lymph node metastases of prostate cancer after primary therapy. Patients and Methods: Twenty-three patients received radiotherapy for PSMA ligand-positive lymph node metastases. Results: The median follow-up time was 12.4 (range=6.0-28.5) months. The median pre-treatment prostate-specific antigen (PSA) decreased from 2.75 (range=0.52-8.92) ng/ml to a nadir of 1.37 (range=0.11-8.00) ng/ml (p=0.001) following radiotherapy. Except for one patient (4.4%), PSA level decreased in 22 patients (95.6%). The biochemical failure-free survival and time to initiation of systemic therapy at the median follow-up were 95.6% and 100%, respectively. Three patients (12.9%) presented with recurrent disease outside the initial radiation field. No grade III acute toxicities or late grade II toxicities were observed. Conclusion: 68Ga-PSMA ligand PET/CT-based radiotherapy is a promising local treatment option for isolated lymph node metastases of prostate cancer.