Serdar Aricia, Sevda Saglampinar Karyagar b, Sener Cihana
a Department of Medical Oncology, University of Health Sciences, Okmeydani Training and Research Hospital, 34384, Istanbul, Turkey
b Department of Nuclear Medicine, University of Health Sciences, Okmeydani Training and Research Hospital, 34384, Istanbul, Turkey
Doi: 10.1016/j.jons.2019.10.001 - Article's Language: EN
Aim: To examine predictive markers for high detection rates of 68Ga PSMA-PET/CT in biochemical
recurrence (BR) prostate cancer (PCa) patients with low PSA levels.
Material and Method: This trial was planned as a retrospective single center study. Patients with BR
prostat cancer were included. PSA levels of all patients were lower 2 mg/l.
Results: Totally thirty-two men patients with BR PCa were included in this study. 18 (56.3%) patients
underwent radical prostatectomy and 14 (43.7%) patients curative intense radiotherapy. The number of
patients received adjuvant maximal androgen blokage (MAB) treatment was 15 (46.9%). Median PSA
levels was calculated 1.03 mg/l 17 (53.1%) of patients had <1 mg/l PSA levels and 7 (21.8%) of patients
<0.5 mg/l. The patients number was 16 in unfavorable intermediate risk group (50.0%), 12 (37.5%) in high
group and 4 (12.5%) in very high group. The median PSA doubling time was 6.2 months. The number of
patients received adjuvant MAB treatment was 15 and in 14 (93.3%) of patients were found positive
lesion in 68Ga PSMA-PET/CT. The number of patients with at least one lesion detected on 68Ga PSMAPET/
CT was 19 (59.4%). In univariate analysis to detect the factors affecting 68Ga PSMA-PET/CT positivity,
there was only the presence of adjuvant MAB treatment as statistically significant importance (p < 0.001)
and in multivariate analysis, the presence of adjuvant MAB treatment was found to be as statistically
significant factor in terms of affecting 68Ga PSMA-PET/CT positivity (p ¼ 0.003). The cut-off value was
calculated as 1.12 mg/l in patients with no adjuvant MAB treatment (sensitivity 80% and specificity 83.3%).
Conclusion: Clinicians may perform 68Ga PSMA PET/CT in low PSA levels to detect lesions in biochemical
recurrent prostate cancer patients who had received MAB treatment and in patients with higher PSA
levels who had no received MAB treatment.