Multiparametric 18F-FDG and 68GA-DOTATOC PET Imaging in Bone Metastatic Meningioma Before Radionuclide Therapy

Abstract

This report presents the case of a 61-year-old woman with assessment of fronto-temporo-sphenoidal refractory meningioma before radionuclide therapy with pretherapeutic 68 Ga-DOTATOC PET/CT. Given the discovery of osteolytic lesions, 18 F-FDG PET/CT is planned to search for the primitive origin. Meningioma bone metastasis is confirmed with spine biopsies. The presence of dedifferentiated meningioma lesions indicating that high somatostatin receptor expression does not necessarily coincide with areas of increased glucose metabolism. 18 F-FDG and 68 Ga-DOTATOC PET/CT allows optimal characterization of tumor heterogeneity and guide targeted therapeutic management before PPRT.

The Role of [68Ga]Ga-DOTA-SSTR PET Radiotracers in Brain Tumors: A Systematic Review of the Literature and Ongoing Clinical Trials

“…DOTATATE (54.5%) was utilized more frequently than DOTATOC (45.5%). In meningiomas, [ 68 Ga]Ga-DOTA-SSTR PET studies were implemented to: (1) evaluate intraosseous or infracranial extension [ 15 , 31 , 79 ]; (2) detect lesions difficult-to-identify on MRI [ 30 , 63 ]; (3) differentiate residual/recurrent tumor tissue versus non-tumor tissue [ 14 ], such as surgical scarring [ 38 ] or post-therapy changes [ 53 ]; (4) confirm the diagnosis of meningiomas (high tracer uptake) [ 35 , 71 , 72 ] and differentiate those from other pathologies with lower tracer uptakes, both tumoral [ 44 , 54 , 55 , 58 ] and non-tumoral [ 40 , 42 ]; (5) stage recurrent or systemic disease [ 34 , 50 , 56 ]; (6) quantify tracer uptake (SSTR2 expression) [ 61 , 62 , 77 ] and match/mismatch with FDG uptake (metabolic rate) [ 35 , 52 ]; (7) evaluate postoperative extent of resection [ 60 , 65 ]; (8) predict tumor growth [ 45 ]; and appraise the diagnostic accuracy of hybrid PET/MRI scans [ 13 , 37 , 63 ]. In pituitary adenomas, [ 68 Ga]Ga-DOTA-SSTR PET studies were utilized to confirm biologically active post-surgical residual tumor tissue in concomitance with FDG PET/CT studies [ 16 ], or for differential diagnosis with synchronous meningiomas [ 44 ].…”

68Ga-DOTATOC Pictorial Essay of Various Recurrent Meningiomas Rejected for Treatment With 177Lu-DOTATATE

“…1 Because meningioma significantly overexpress somatostatin receptors, compassionate treatment with 177 Lu-DOTATATE is possible in the event of recurrent lesion with convincing results. 2 However, this requires prior confirmation of the binding of the radiolabeled analogues by the lesion using somatostatin receptor imaging radiolabelled with 68 Ga or 18 F. 3,4 Unfortunately, most of our patients did not show any uptake exceeding the liver uptake on PET/CT 68 Ga-DOTATOC recusing this treatment. This low uptake was probably due to the loss of receptor overexpression following radiotherapy or in the context of more aggressive dedifferentiated lesions.…”

Management of a Patient With Metastatic Gastrointestinal Neuroendocrine Tumor and Meningioma Submitted to Peptide Receptor Radionuclide Therapy With 177Lu-DOTATATE

“…Somatostatin receptor type 2 overexpression represents the target for functional imaging and PRRT of gastrointestinal NETs 1 ; because meningiomas are characterized by high somatostatin receptor type 2 expression, 2,3 radiolabelled somatostatin analogs have been successfully used both for diagnosis 4 and therapy of these tumors 5,6 . There are limited data available about the prevalence of incidental meningiomas in patients affected by NET 7,8 . There are even less information about efficacy and safety of patients with this setting, often limited to single case reports.…”

“…5,6 There are limited data available about the prevalence of incidental meningiomas in patients affected by NET. 7,8 There are even less information about efficacy and safety of patients with this setting, often limited to single case reports. In our case, a 4 cycles' scheduled treatment with a cumulative activity of 29.…”