Hematology, Transfusion and Cell Therapy (Apr 2024)
PROFILE OF MENINGIOMAS IN DOTATOC-68GA, FDG-18F AND PSMA-68GA PET/CT STUDIES: REALITY OF A PRIVATE SERVICE OF NUCLEAR MEDICINE AND LITERATURE REVIEW
Abstract
Summary: Meningiomas represent the most common group of central nervous system primary tumors, and are often incidental findings on neuroimaging exams. The World Health Organization classifies meningiomas into three grades (grades I-III), varying in risk of recurrence and mortality. Approximately 100% of meningiomas present expression of the somatostatin receptor type 2 (SSTR2), which, in recent years, has been highlighted by the literature as a possible theranostic tool, confirming the relevance of PET/CT with SSTR ligands in this context. Based on a narrative literature review, the objective was to analyze the main characteristics of meningiomas found in DOTATOC-68Ga PET/CT, FDG-18F PET/CT and PSMA-68Ga PET/CT exams performed in a private nuclear medicine service. Subsequently, the data obtained was compared with evidence from the studies consulted. A search tool connected to the RIS database was used, utilizing the search word meningioma in PET/CT exam reports, from February 2019 to January 2024. As a result, exams from 68 patients were found, including 19 PET/CT DOTATOC-68Ga, 45 PET/CT FDG-18F and 4 PET/CT PSMA-68Ga. The absolute number per age group was 8 (40-49 years), 12 (50-59 years), 15 (60-69 years), 19 (70-79 years) and 14 (80 years or more), among which 47 were women and 21 men. Among all studies, 12 (17.6%) were indicated for meningioma specific evaluation, varying between initial diagnosis, radiosurgery programming, post-resection evaluation and uncleared focal neurological signs, which represented 57.9% (11) of the DOTATOC-68Ga PET/CT sample and 2.2% (1) of FDG-18F PET/CT. All PSMA-68Ga PET/CT studies had another indication. Within all lesions evaluated, 61 were unifocal and 7 were multifocal. The largest diameter of the lesions analyzed ranged from 5 to 66 mm (average 23 mm). Based on the 68 patients analyzed in the sample, highlighting the existence of multifocal lesions, the topographies observed were: parasagittal 23, hemispherical convexity 30, sphenoid and middle cranial fossa 12, cerebellar convexity 1, frontobasal 4, posterior fossa 2 and foramen magnum 1. All lesions evaluated by DOTATOC-68Ga PET/CT showed tracer uptake (SUV between 2.5 and 17.8, mean SUV 8.9), compared to 3 lesions evaluated by FDG PET/CT-18F (SUV between 4.9 and 7.2, mean SUV 6.1). No lesion showed significant uptake of PSMA-68Ga. Conclusão: In the context of increasing advances in molecular imaging with SSTR ligands for meningiomas, PET/CT studies have showed relevance, above all, in the initial evaluation (pre-surgical/pre-radiotherapeutic), in the scenario of suspected tumor recurrence, as well as for candidates to radionuclide therapy. The present work sought to analyze information that could corroborate the characteristics of such tumors in hybrid images, comparing the data found with current literature. In addition, highlight the potential use of FDG-18F uptake in the non-invasive assessment of the aggressiveness of meningiomas.
