reported that an SRC gastric cancer is negative on 68Ga-PSMA PET/CT but positive on 68Ga-FAPI PET/CT ( Pang et al., 2020). Yang Lu, in Reference Module in Biomedical Sciences, 2022 Other investigational PET tracersĦ8Ga-Fibroblast activation protein inhibitor (FAPI) PET/CT has recently been used for Cancer-associated fibroblasts (CAFs) imaging and showed great promise ( Kratochwil et al., 2019). In primis, 68Ga-DOTATATE uptake has been demonstrated to be a reliable predictor of tumor growth of progressive meningiomas ( Seystahl et al., 2016) in secundis, this can be the best radiopharmaceutical in this specific clinical setting due to its added value as preliminary imaging tracer before considering 177Lu-Lutathera as a valid theragnostic agent for recurrent and malignant meningiomas ( Braat et al., 2019).įor the same reason, preliminary suggestions from literature support 68Ga/ 177Lu- labeled PSMA in diagnosis and treatment of glioblastoma multiforme ( Kumar et al., 2020). Ferdinando Calabria, Department of Nuclear Medicine and Theranostics, “Mariano Santo” Hospital, Cosenza, Italy, pag. Morphological CT aspect and localization of this 68Ga-DOTATOC-avid lesion allowed diagnosis of meningioma. Tracer uptake in the brain corresponded to a hyperdense area in the right encephalic lobe, close to the falx cerebri, displayed in relative axial PET/CT (D) and CT (E) views and coronal PET/CT (F) and CT (G) views. 68Ga-DOTATOC uptake was associated with an 8 mm comprehensive pulmonary node in the left inferior lobe, considered as metastasis of neuroendocrine tumor, evident in axial PET/CT (B) and CT (C) views with lung parenchyma window. Whole-body PET Maximum Intensity Projection displayed focal tracer uptake in the left lung and in the brain (A). A 59-the year-old patient was examined with 68Ga-DOTATOC whole-body PET/CT, 3 years after surgical excision of neuroendocrine tumor of the left lung. Undoubtedly, the low rate of the normal distribution of 68Ga-PSMA could easily allow the PET/MRI identification of brain tumors false-positive cases, due to lesions expressing prostate membrane antigen, should be accurately kept into consideration.įig. However, these studies need to be considered as preliminary, being reports of a case or developed on few examined populations. Recently, it has been demonstrated a feasible role of 68Ga-PSMA in differentiating low-grade from high-grade brain gliomas, utilizing semiquantitative analysis ( Verma et al., 2019), in evaluating pseudoprogression of glioblastoma ( Gupta et al., 2020) or newly diagnosed glioblastoma ( Moreau et al., 2019). Utilizing PET, the uptake of 68Ga-PSMA was considered as tumor relapse. MRI, consequently performed, confirmed craniotomy and lacunar area with hypointense hemosiderin deposition and hyperintense borders (B, T2 weighted image) in the lacuna area in the left cerebellar hemisphere, without significant contrast enhancement, except for residual meningeal enhancement (C, post-contrast T1 view). Brain PET showed an area of mild uptake in left cerebellar lobe (A). No foci of pathologic uptake due to prostate cancer relapse were detected. A 64-year-old patient examined for restaging prostate cancer after radical prostatectomy undergone 68Ga-PSMA PET/CT the patient was previously submitted (2 years before the scan) to surgical excision of glioblastoma in the left occipital lobe and ipsilateral cerebellar lobe consequently, a further PET/CT of the brain was performed. Similar results are also known for a variant of PSMA, labeled with 64Cu ( Calabria et al., 2019).įor these reasons, a lack of specificity in the brain is also known for this tracer caution and the correlative approach with MRI should be of the utmost importance in order to correctly identify a 68Ga-PSMA-avid lesion in the brain.įig. To date, is known the possibility to detect 68Ga-PSMA uptake in lesions as melanoma metastases ( Hod et al., 2020), cerebral tuberculosis ( Wong et al., 2020), and also rare but not uncommon brain metastases of prostate cancer ( Chan et al., 2017).
#Netspot pet series#
PSMA is the acronym for Prostate-Specific Membrane Antigen and presents a low gradient of uptake in the brain: despite the term “ specific,” since their first use, it has emerged an extensive series of benign and malignant conditions, generally as reports of a case, demonstrating 68Ga-PSMA uptake in the brain, not linked to prostate cancer. Orazio Schillaci, in Reference Module in Biomedical Sciences, 2021 68Ga-PSMAĦ8Ga-PSMA is a more recent tracer, useful in detecting prostate cancer recurrence in patients with biochemical relapse, earlier than radiolabeled choline.