A prospective randomized multicenter study on the impact of 18F-Choline PET/CT versus conventional imaging for staging intermediate - to high-risk prostate cancer

This study aimed to compare the efficacy of [18F]F-choline PET/CT with conventional imaging for staging and managing intermediate- to high-risk prostate cancer (PCa). The primary objective was to assess the ability of PET/CT with [18F]F-choline to identify lymph node and systemic involvement during initial staging. Secondary objectives included evaluating the impact of [18F]F-choline PET/CT on unnecessary local treatments and assessing the safety of [18F]F-choline agents. Additionally, the study aimed to analyze recurrence-free survival and overall survival 5 y after randomization. Methods: A prospective controlled, open, randomized multicenter phase III trial involving 7 Italian centers was conducted. Eligible patients with intermediate- to high-risk PCa were randomized in a 1:1 ratio. Two groups were formed: one undergoing conventional imaging (abdominopelvic contrast-enhanced CT and bone scanning) and the other receiving conventional imaging plus [18F]F-choline PET/CT. The study was terminated prematurely; however, all the endpoints were thoroughly analyzed and enriched. Results: Between February 2016 and December 2020, 256 patients were randomly assigned. In total, 236 patients (117 in the control arm and 119 in the experimental arm) were considered for the final assessment. In the experimental arm, the sensitivity for lymph node metastases, determined by final pathology and serial prostate-specific antigen evaluations, was higher than in the control arm (77.78% vs. 28.57% and 65.62% vs. 17.65%, respectively). The [18F]F-choline was tolerated well. The use of [18F]F-choline PET/CT resulted in an approximately 8% reduction in unnecessary extended lymphadenectomy compared with contrast-enhanced CT. Additionally, [18F]F-choline PET/CT had a marginal impact on 5-y overall survival, contributing to a 4% increase in survival rates. Conclusion: In the initial staging of PCa, [18F]F-choline PET/CT exhibited diagnostic performance superior to that of conventional imaging for detecting metastases. [18F]F-choline PET/CT reduced the rate of unnecessary extensive lymphadenectomy by up to 8%. These findings support the consideration of discontinuing conventional imaging for staging PCa.