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.
PSMA (prostate-specific membrane antigen) is overexpressed in prostate cancer cells and is reported to be a promising target for antibody-based radioligand therapy in patients with metastasized prostate cancer.
<sup>68</sup>Ga-PSMA PET/CT had a high detection rate of PCa recurrence outside the prostatic fossa in pts. being considered for salvage RT (22.4% PET-positive pelvic lymph nodes and 4.1% distant metastases).
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) is specific for prostate cancer cells; nevertheless when finding uptake in abnormal locations for prostate cancer metastases, it is important to consider other hypothesis, including second cancers.
Prostate-specific membrane antigen (PSMA) PET/CT detects PCa metastasis with superior accuracy, having a potential impact on the planning of definitive radiation therapy (RT) for nonmetastatic PCa.
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.
In particular, we focus on the utility of PSMA-PET for diagnostic evaluation of isolated or limited metastases planned for local surgery or radiation, as well as the potential utility of PSMA-PET for therapeutic response assessment in patients receiving stereotactic ablative body radiotherapy (SABR).
Ga PSMA PET/CT done in view of increased PSA levels and clinically suspicious hard lesion in prostate showed primary lesion in left side of prostate with metastases to the right temporal bone.
This case shows the importance of including schwannoma in the differential diagnostic evaluation of patients with Ga-PSMA-positive foci in paravertebral locations, as schwannomas may show avid PSMA uptake and may potentially lead to an incorrect diagnosis of metastasis.
Six patients with iodine-negative and F-FDG-positive metastasized DTC (mean TG, 1616 ng/mL) received 71-93 MBq of the Ga-labeled PSMA ligand and underwent PET/CT at 62 ± 7 minutes p.i.. Tumor accumulation capacity of the tracer and the detection rate of local recurrences and metastases were compared with F-FDG.
The mean SUV<sub>max</sub> of PSMA-negative metastases was 1.0±0.5 in 2D ROI and 1.0±0.4 in 3D ROI, and significantly lower than that of the pulmonary opacities (p<0.001).
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.
The type II integral membrane protein, prostate specific membrane antigen (PSMA) is overexpressed on prostate cancer cells in proportion to the stage and grade of the tumor progression, especially in androgen-independent, advanced and metastatic disease, rendering it a promising diagnostic and/or therapeutic target.
At a median follow-up interval of 10 months (range 3-40 months), 1 patient experienced a biochemical recurrence according to the Phoenix criteria, and prostate-specific membrane antigen testing revealed that this was due to a distant nodal metastasis.