PET-CT 18F-PSMA 1007 in the staging of patients with prostate cancer prior to curative intent radiotherapy: a prospective observational study

Abstract

Objective: The objective of our study was to assess whether there are staging changes in CaP with PET PSMA compared to standard diagnostic methods, and if these changes occurred, to understand how they altered the treatment of patients with an initial diagnosis of CaP and their relationship with the D'amico score.

Methods: We present a prospective observational study conducted on patients initially diagnosed with prostate cancer, who underwent standard staging studies alongside PET PSMA imaging.

Results: Forty patients diagnosed with prostate cancer were staged using standard diagnostic methods and PET PSMA. In 40% of the patients, initial staging changed based on the results obtained from PET PSMA. After PET PSMA, the uro-oncology committee decided to modify the initial treatment plan in 27.5% of the cases, including radiation boost targeting the extra-prostatic lesions detected by PET PSMA. When correlating the change in staging with PET PSMA versus the D'amico risk score, no changes were observed in the low-risk group, 19% in the intermediate-risk group, and 62% in the high-risk group. These differences were statistically significant (X2=9.2; df=2; p=0.01).

Limitation and value: The study faced limitations in sample size and lack of long-term patient follow-up. However, it highlights key contributions: the promising evaluation of PET PSMA in staging, its influence on therapeutic decisions, and its association with the D'amico score.

Conclusion: PET PSMA showed substantial changes in CaP staging, particularly in higher-risk patients, suggesting its potential utility in guiding therapeutic decisions before radiotherapy.