Evaluation of the clinical use of PET/CT with 68Ga-PSMA for the assessment of biochemical recurrence of low or intermediate-risk prostate cancer

Abstract

Rationale: ⁶⁸Ga-prostate-specific membrane antigen positron emission tomography/computed tomography (PET-PSMA) has shown promising performance for the assessment of biochemical recurrence of prostate cancer in high-risk patients, defined by D´Amico et al. criteria. Little evidence for the impact of this diagnostic method for patients at low or intermediate risk, in terms of management and benefits of subsequent treatment, is available.

Methods: Data from 57 patients with low and intermediate-risk prostate cancer and biochemical recurrence underwent PET-PSMA were examined retrospectively. Images were analyzed and findings were compared with clinical data. Indications for the PET-PSMA imaging, study positivity/negativity, lesion locations, Gleason (ISUP) score, prostate-specific antigen (PSA) level on the examination date, postexamination treatment, and management were evaluated.

Results: PET-PSMA findings were negative for 28 (49.12%) patients, 11 of whom received salvage radiotherapy (S-RT; with or without HT; PSA levels declined significantly in 10 (90.9%) of these patients compared with levels in those not undergoing S-RT. Positive PET-PSMA findings enabled the accurate identification of patients who benefited from salvage pelvic RT for local disease control and those who responded satisfactorily to systemic treatment.

Conclusion: PET-PSMA is useful for the assessment of biochemical recurrence in prostate cancer patients with prostate cancer at low and intermediate-risk.

Keywords: Biochemical recurrence; Gallium; Local; Neoplasm recurrence; Positron emission tomography computed tomography; Prostate cancer; Prostate-specific membrane antigen, Human; Radioisotopes; Salvage Treatments.