The impact of [68Ga]PSMA I&T PET/CT on radiotherapy planning in patients with prostate cancer.

Abstract

To determine the impact of Gallium-68-labled prostate-specific membrane antigen positron-emission tomography/computed tomography ([68Ga]PSMA PET/CT) on radiotherapy planning for primary disease, biochemical cancer relapse, and advanced disease of prostate cancer. Atotal of 106 patients with prostate cancer scheduled for radiation therapy underwent 120[68Ga]PSMA PET/CT scans prior to radiotherapy treatment. In 20cases, patients underwent [68Ga]PSMA PET/CT for primary therapy(PT), 75cases were referred for biochemical relapse after surgery(RL), and 25cases were intended for palliative treatment of localized metastases(MD). We retrospectively compared the impact of [68Ga]PSMA PET/CT on lesion detection and treatment decision to CT alone. [68Ga]PSMA PET/CT revealed atotal of 271 positive lesions, whereas CT detected 86lesions (32%). Overall, the radiotherapy regime was changed in 55 of 120 cases (46%) based on the higher detection rate of [68Ga]PSMA PET/CT: in 15% of cases with PT, in 43% of cases with RL, and in 44% of cases with MD. [68Ga]PSMA PET/CT is superior to CT alone for lesion detection in prostate cancer, thereby significantly impacting on radiotherapy planning for primary disease, biochemical cancer relapse, and advanced disease of prostate cancer.