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

• Published in: Cancer biology & medicine Vol. 16; no. 1; pp. 157 - 166
• Main Authors: Tan, Janice S H, Goh, Charles X Y, Koh, Yen Sin, Li, Youquan, Tuan, Jeffrey K L, Chua, Eu Tiong, Tan, Terence W K, Wang, Michael L C, Lee, Lui Shiong, Tay, Kae Jack, Kanesvaran, Ravindran, Toh, Chee Keong, Tong, Aaron K T, Lam, Winnie W C, Chua, Melvin L K
• Format: Journal Article
• Language: English
• Published: Tianjing China Division of Radiation Oncology, National Cancer Centre Singapore, Singapore 169610%Department of Nuclear Medicine and Molecular Imaging, Singapore General Hospital, Singapore 169610 01.02.2019; Department of Surgery, Sengkang General Hospital, Singapore 544886%Department of Urology, Singapore General Hospital, Singapore 169610%Oncology Academic Clinical Programme, Duke-NUS Medical School, Singapore 169857; Oncology Academic Clinical Programme, Duke-NUS Medical School, Singapore 169857%Department of Urology, Singapore General Hospital, Singapore 169610; Oncology Academic Clinical Programme, Duke-NUS Medical School, Singapore 169857; Division of Medical Sciences, National Cancer Centre Singapore, Singapore 169610, Singapore; Radiological Sciences Academic Clinical Programme, Duke-NUS Medical School, Singapore 169857%Division of Radiation Oncology, National Cancer Centre Singapore, Singapore 169610; Division of Medical Oncology, National Cancer Centre Singapore,Singapore 169610%Division of Radiation Oncology, National Cancer Centre Singapore, Singapore 169610; Chinese Anti-Cancer Association; China Anti-Cancer Association
• Subjects: 68Ga PSMA PET/CT; Asian; diagnostic; Original; prostate cancer; prostatectomy; recurrence; salvage radiotherapy; recurrence; prostate cancer; salvage radiotherapy; prostatectomy; diagnostic; Asian; 68Ga PSMA PET/CT
• ISSN: 2095-3941; 2095-3941
• DOI: 10.20892/j.issn.2095-3941.2018.0288

OBJECTIVEProstate 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 68Ga-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. METHODS68Ga 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 68Ga PSMA-PET/CT were evaluated, and impact on management was reviewed by comparison with CWU. RESULTSMedian time to BCR post-RadP was 8.1 months. Detection rate for 68Ga 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, 68Ga 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. CONCLUSIONSIn the present report, we demonstrated the diagnostic and treatment decision utility of 68Ga 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.