Predictive Values of Preoperative [68Ga]Ga-PSMA-11 PET/CT in Patients With Suspected Brain Tumours of Glial Origin

Comparison of the incidence of positive preoperative [68Ga]Ga-PSMA-11 PET/CT results with the final histopathological diagnosis based on the 5th edition of the WHO (World Health Organization) Classification of Tumours of the Central Nervous System (2021). The PET scan in this regard will be evaluated qualitatively - in terms of finding accumulation in the projection of the brain tumor (positive result) and lack of accumulation in the projection of the brain tumor (negative result). The histopathological diagnosis will take into account the subtypes of the tumor according on the 5th edition of the WHO (World Health Organization) Classification of Tumours of the Central Nervous System (2021) - including the histopathological examination and the genetic diagnosis - adult-type diffuse gliomas comprise of three distinct types: Astrocytoma, IDH-mutant, Oligodendroglioma, IDH-mutant and 1p/19q-codeleted, and Glioblastoma, IDH-wildtype

Comparison of the preoperative [68Ga]Ga-PSMA-11 PET/CT semiquantitative parameters with with the final histopathological diagnosis. The maximal standard uptake value (SUVmax) of each positive lesion were measured using the spherical volume of interest (VOI). The histopathological diagnosis will take into account the subtypes of the tumor according on the 5th edition of the WHO (World Health Organization) Classification of Tumours of the Central Nervous System (2021) - including the histopathological examination and the genetic diagnosis - adult-type diffuse gliomas comprise of three distinct types: Astrocytoma, IDH-mutant, Oligodendroglioma, IDH-mutant and 1p/19q-codeleted, and Glioblastoma, IDH-wildtype.

Comparison of the preoperative [68Ga]Ga-PSMA-11 PET/CT semiquantitative parameters with with the final histopathological diagnosis. The mean standard uptake value (SUVmean) of each positive lesion were measured using the spherical volume of interest (VOI). The histopathological diagnosis will take into account the subtypes of the tumor according on the 5th edition of the WHO (World Health Organization) Classification of Tumours of the Central Nervous System (2021) - including the histopathological examination and the genetic diagnosis - adult-type diffuse gliomas comprise of three distinct types: Astrocytoma, IDH-mutant, Oligodendroglioma, IDH-mutant and 1p/19q-codeleted, and Glioblastoma, IDH-wildtype.

Comparison of the preoperative [68Ga]Ga-PSMA-11 PET/CT semiquantitative parameters with with the final histopathological diagnosis. The Target-to-background ratios (TBR) were calculated using SUVmax of the lesion divided by SUVmax of the background measured using a VOI of a similar diameter, placed in a distant, unaffected region, representing normal brain tissue. The histopathological diagnosis will take into account the subtypes of the tumor according on the 5th edition of the WHO (World Health Organization) Classification of Tumours of the Central Nervous System (2021) - including the histopathological examination and the genetic diagnosis - adult-type diffuse gliomas comprise of three distinct types: Astrocytoma, IDH-mutant, Oligodendroglioma, IDH-mutant and 1p/19q-codeleted, and Glioblastoma, IDH-wildtype.

Comparison of the preoperative [68Ga]Ga-PSMA-11 PET/CT semiquantitative parameters with with the final histopathological diagnosis. Target-to-liver background ratios (TLR) were calculated by dividing SUVmax of the lesion by SUVmean of the liver (the liver VOI of a similar diameter placed in the central area of the right liver lobe was used). The histopathological diagnosis will take into account the subtypes of the tumor according on the 5th edition of the WHO (World Health Organization) Classification of Tumours of the Central Nervous System (2021) - including the histopathological examination and the genetic diagnosis - adult-type diffuse gliomas comprise of three distinct types: Astrocytoma, IDH-mutant, Oligodendroglioma, IDH-mutant and 1p/19q-codeleted, and Glioblastoma, IDH-wildtype.

Comparison of the preoperative [68Ga]Ga-PSMA-11 PET/CT with the immunohistopathological staining of the tumour tissue. The maximal standard uptake value (SUVmax) of each positive lesion were measured using the spherical volume of interest (VOI). The immunoreaction will be analyzed in the endothelium and in tumor cells. A score will be assigned semiquantitatively based on staining intensity and distribution as follows: 0 - negative, 1- faint and weak staining at high power; 2- moderate intensity at low power; and 3- strong reaction at low power.

Comparison of the incidence of positive preoperative [68Ga]Ga-PSMA-11 PET/CT results with the progession free survival time. The PET scan in this regard will be evaluated qualitatively - in terms of finding accumulation in the projection of the brain tumor (positive result) and lack of accumulation in the projection of the brain tumor (negative result). The time will be measured in weeks.

Comparison of the incidence of positive preoperative [68Ga]Ga-PSMA-11 PET/CT results with the overall survival time. The PET scan in this regard will be evaluated qualitatively - in terms of finding accumulation in the projection of the brain tumor (positive result) and lack of accumulation in the projection of the brain tumor (negative result). The time will be measured in weeks.

Comparison of the incidence of positive preoperative [68Ga]Ga-PSMA-11 PET/CT results with progession free survival time. The maximal standard uptake value (SUVmax) of each positive lesion were measured using the spherical volume of interest (VOI). The time will be measured in weeks.

Comparison of the incidence of positive preoperative [68Ga]Ga-PSMA-11 PET/CT results with the overall survival time. The maximal standard uptake value (SUVmax) of each positive lesion were measured using the spherical volume of interest (VOI). The time will be measured in weeks.