⁶⁸Gallium-labelled PSMA-PET/CT as a diagnostic and clinical decision-making tool in Asian prostate cancer patients following prostatectomy

Abstract

Objective Prostate cancers (PCa) in Asian individuals are molecularly distinct from those found in their Caucasian counterparts. There is no risk stratification tool for Asian men with rapid biochemical recurrence (BCR) following radical prostatectomy (RadP). This study aims to assess the detection rate of 68 Ga-prostate-specific membrane antigen-positron emission tomography/computed tomography (PSMA-PET/CT) for diagnosis of clinical recurrence and as a treatment decision making tool in Asian patients with BCR post-RadP. Methods 68 Ga PSMA-PET and CT body with/without bone scan [conventional workup (CWU)] were performed in 55 Asian patients with BCR within 36 months post-RadP. Two blinded reviewers assessed the images. Detection rates of 68 Ga PSMA-PET/CT were evaluated, and impact on management was reviewed by comparison with CWU. Results Median time to BCR post-RadP was 8.1 months. Detection rate for 68 Ga PSMA-PET/CT was 80% (44/55). A positive scan was significantly associated with increasing prostate-specific antigen (PSA) level [odds ratio (OR) = 1.13 (95% CI 1.05–1.30), P = 0.017], but not with higher Gleason grade or shorter PSA doubling time. Compared to CWU, 68 Ga PSMA-PET/CT detected an additional 106 lesions in 33/44 patients with a positive scan, resulting in a change in management in 25/44 (56.8%) patients: 10 to hormonal therapy (HT) and whole pelvis radiotherapy (RT) in addition to bed RT, and 15 to palliative HT alone. Conclusions In the present report, we demonstrated the diagnostic and treatment decision utility of 68 Ga PSMA-PET/CT in Asian men with rapid BCR. Detection of small volume nodal and systemic recurrences at low PSA levels (< 1.0 ng/mL) highlights the role of the tool in assigning patients to treatment intensification with HT-RT or palliative HT in polymetastatic disease.

“Seeing Is Believing”: Additive Utility of 68Ga-PSMA-11 PET/CT in Prostate Cancer Diagnosis

“…The administered radioactivity of 68 Ga-PSMA-11 ranged from 104 MBq to 152 MBq. Following the department's protocol [14], patients underwent scanning with a delay of 60 to 75 min after the tracer injection. CT scans were performed for attenuation correction and anatomical correlation.…”

Management impact of 18F-DCFPyL PET/CT in hormone-sensitive prostate cancer patients with biochemical recurrence after definitive treatment: a multicenter retrospective study

“…PSMA is a transmembrane protein which is overexpressed in malignant prostatic tissue [9,10]. In addition to the widely used 68 Gallium-PSMA-11 [11], 18 F-DCFPyL is a promising novel, second-generation 18 Fradiolabeled tracer [12]. Both radiotracers demonstrated improved detection of metastases compared to conventional imaging techniques, such as computed tomography (CT), bone scan, or magnetic resonance imaging (MRI) [8,13,14].…”