Integration of 68Ga-PSMA-PET/CT in Radiotherapy Planning for Prostate Cancer Patients

Onal C., Torun N., Akyol F., Guler O. C., HÜRMÜZ P., Yildirim B. A., ...More

CLINICAL NUCLEAR MEDICINE, vol.44, no.9, 2019 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 44 Issue: 9
  • Publication Date: 2019
  • Doi Number: 10.1097/rlu.0000000000002691
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: prostate cancer, Ga-68-PSMA-PET, CT, radiotherapy, staging, PET/CT, TOMOGRAPHY, C-11-CHOLINE, DELINEATION, METASTASES, ACCURACY, THERAPY, FAILURE, LIGAND
  • Hacettepe University Affiliated: Yes


Purpose To assess the role of (68)Gallium-labeled-prostate-specific membrane antigen PET/CT (Ga-68-PSMA-PET/CT) in risk group definition and radiotherapy planning in the initially planned definitive radiotherapy (RT) for prostate cancer patients. Methods The clinical data of 191 prostate cancer patients treated with definitive intensity-modulated RT were retrospectively analyzed. All patients were initially staged with thoracoabdominal CT and bone scintigraphy, and the second staging was performed using Ga-68-PSMA-PET/CT. Both stages were evaluated for the decision making of RT and any change in RT target volumes. Results After staging with Ga-68-PSMA-PET/CT, 26 patients (13.6%) had risk group changes, 16 patients (8.4%) had an increase in risk group, and 10 patients (5.2%) had a decrease in risk group. Down-staging occurred in 22 patients (11.5%), and upstaging was observed in 30 patients (15.7%). A total of 26 patients (13.6%) had nodal stage changes. After the Ga-68-PSMA-PET/CT scans, the number of metastatic patient increased to 17 (8.9%), with 4 of them moving from oligo- to polymetastatic disease. An additional irradiation of pelvic lymphatics and metastatic site was performed in 13 patients (6.8%) and 6 patients (3.2%), respectively. The RT was aborted in 4 patients (2.1%) because of parenchymal or distant site metastasis observed in the Ga-68-PSMA-PET/CT. Conclusions We found that Ga-68-PSMA-PET/CT causes considerable migration in stage, risk group, and RT field arrangements, especially in high-risk patients regardless of the GS and baseline prostate-specific antigen values alone. Ga-68-PSMA-PET/CT seems to have a great influence on RT decision making in prostate cancer patients.