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.
Gallium-68 prostate-specific membrane antigen positron emission tomography is now an established imaging technique that has been developed in response to inadequacies in standard of care imaging modalities to improve the detection of metastatic disease in prostate cancer, particularly in the setting of disease recurrence.
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.
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.
Our results suggest that <sup>68</sup>Ga-PSMA-11 PET/CT might be a valuable tool for the detection and follow-up of bone metastases in patients with metastasized prostate cancer.
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%).
Regional and template-based correlations between the presence of LN metastases on histopathology and whole-body PSMA-11 PET/CT(MRI) results were evaluated.
Thus, PSMA has theoretically been discussed as a possible future target for systemic radioligand therapy with <sup>177</sup>Lu-PSMA-617 even in non-prostate malignancies 1.Here we report on a female patient with extended metastasized leiomyosarcoma experimentally treated with one application of <sup>177</sup>Lu-PSMA-617 radioligand therapy.
<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.
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.
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.
We describe the technique using PSMA-PET imaging to pre-operatively localise areas of low-volume nodal metastatic disease with hookwire to allow targeted lymph node dissection with direct visualisation and palpation to ensure adequate clearance of involved nodes.
Studies evaluating men with prostate cancer biochemical recurrence after definitive therapy and without known metastatic disease who underwent prostate specific membrane antigen positron emission tomography/computerized tomography to detect recurrent disease were included in analysis.
<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.