Impact of 68Ga-PSMA PET/CT on Survival and Management in Prostate Cancer.

ABSTRACT

BACKGROUND: 68Ga-labeled prostate-specific membrane antigen positron emission tomography-computed tomography (68Ga-PSMA PET/CT) has led to altered treatment plans for prostate cancer (PCa) patients. OBJECTIVE: This study aimed to investigate the impact of 68Ga-PSMA PET/CT on overall survival (OS) and management in PCa. METHODS: Consecutive 100 patients who had 68Ga-PSMA PET/CT and conventional imaging (CI) were included in this retrospective study. Disease stages and treatment plans according to both CI and 68Ga-PSMA PET/CT were compared. The effect of 68Ga-PSMA PET/CT on OS was assessed. RESULTS: After 68Ga-PSMA PET/CT, the stage changed in 64 patients (64%). By the reason of 68Ga-PSMA PET/CT findings, treatment plans based on CI were changed in 73 patients (73%). According to the ROC analysis, patients with a PSA value below 8 had higher rates of change in staging (p<0.0001) and treatment (p=0.034). Both a PSA below 8 (OR 8.79 95% CI (2.72-28.43), p<0.001), and having a hormone-sensitive disease at the time of imaging (OR 5.6 95% CI (1.35-23.08), p=0.017) were significant independent factors predicting change in staging with 68Ga-PSMA PET/CT. The results of a phi correlation coefficient analysis showed a significant relationship between therapy and changes in staging (ϕ=0.638, p<0.0001). Two-year OS was statistically different in hormone-sensitive patients with and without treatment change (95% vs 81%, p=0.006). CONCLUSION: 68Ga-PSMA PET/CT has the effect of changing the treatment in 73% of PCa patients. There is a positive correlation between the changes in staging and treatment. Survival of hormone sensitive patients has improved due to treatment changes based on PET/CT findings.