In 51 patients, for patient-based analysis, the sensitivity, specificity and accuracy of Ga-PSMA PET-CT in detecting lymphnodal metastases were 80, 90.3 and 86.3%, respectively, and for lesion-based analysis 69.2, 99.6 and 98.4%, respectively.
Therefore, the present study aimed to evaluate the role of PSMA PET/CT in detecting nodal metastases in a large cohort of men and compare imaging results with the risk of lymph node involvement based on the Roach formula.
Prostate specific membrane antigen (PSMA) positron-emission tomography/computed tomography (PET/CT) is a novel and promising imaging modality which aims to overcome the incapability of early identification of distant and regional metastases.
The high prostate-specific membrane antigen expression in prostate cancer metastases makes it a promising approach for targeted radionuclide therapy of prostate cancer.
Positron emission tomography (PET) with prostate-specific membrane antigen (PSMA) is a promising technique that outperformed conventional imaging in the detection of nodal and distant metastases in previous studies.
Patients with newly-diagnosed M1a/b prostate cancer (PSMA PET/CT staging is permitted) and 1-5 radiographically visible metastases (excluding pelvic lymph nodes) are undergoing local treatment with radical prostatectomy, limited duration systemic therapy for a total of six months (leuprolide, abiraterone acetate with prednisone, and apalutamide), metastasis-directed stereotactic body radiotherapy (SBRT), and post-operative fractionated radiotherapy if pT ≥ 3a, N1, or positive margins are present.
Alternatively, fluorine-18 (<sup>18</sup>F)-labelled PSMA tracers are available, such as <sup>18</sup>F-DCFPyL, which offer enhanced image quality and therefore potentially increased detection of small metastases.
At multivariate analysis, age, sex, histotype, vascular invasion, T and N parameters, and PSMA positivity were significant predictors of distant metastases.The AUC was 0.92.
<b>Results:</b> The projected dosimetry for <sup>90</sup>Y-PSMA-617 estimated a mean kidney dose of 3.47 ± 1.40 Gy/GBq, red marrow dose of 0.11 ± 0.04 Gy/GBq, and salivary gland dose of 5.57 ± 1.34 Gy/GBq; randomly chosen metastases were approximated with 22.8 ± 16.10 Gy/GBq.
<b>Methods:</b> PSMA protein expression in tissue samples from 50 ACCs, 90 ACAs (including 20 from patients who presented with Cushing's syndrome, 20 aldosterone-producing adenomas and 50 non-functional tumors) and 10 tissues that were metastases from other primary sites was assessed by immunohistochemistry.
PATIENT SUMMARY: In selected patients with prostate-specific antigen (PSA) increase during androgen deprivation, metastases were detected with prostate-specific membrane antigen positron emission tomography imaging.
PSMA PET-CT showed findings compatible with local disease in 47 patients (66.2%), lymph node metastases in 10 patients (14.1%) and distant metastases in 14 patients (19.7%).
<sup>68</sup>Ga-PSMA PET/CT is a valuable tool for the detection of PC local recurrence or extraprostatic metastases following rising PSA levels after primary definitive therapy and should be incorporated during routine work-up.
Regional and template-based correlations between the presence of LN metastases on histopathology and whole-body PSMA-11 PET/CT(MRI) results were evaluated.
A significant (p ≤ 0.05) correlation between SUV<sub>max</sub> in PSMA-positive liver metastases and both size (ρ<sub>Spearman</sub> = 0.57) of metastases and PSA serum level (ρ<sub>Spearman</sub> = 0.60) was found.
Compared to bone scan, PSMA-PET is more sensitive and specific to detect metastases but the therapeutic consequences of PSMA-PET results in the setting of CRPC remain unclear.
Our purpose was to assess whether the addition of data from multiparametric pelvic MRI (mpMR) and whole-body MRI (wbMR) to the interpretation of <sup>18</sup>F-fluoromethylcholine (<sup>18</sup>F-FCH) or <sup>68</sup>Ga-HBED-CC PSMA-11 (<sup>68</sup>Ga-PSMA) PET/CT (=PET) improves the detection of local tumor recurrence or of nodal and distant metastases in patients after radical prostatectomy with biochemical failure.
Although it is generally accepted that higher PSA values indicate higher disease burden, few data are available on the relation between PSA levels and number of detected metastases on PSMA PET/CT.
In the present study, <sup>64</sup> Cu-PSMA-617-PET demonstrated to be feasible for imaging prostate cancer for both the primary tumor site and metastases.