PET/CT using <sup>68</sup>Ga‐PSMA‐617 versus <sup>18</sup>F‐fluorodeoxyglucose to differentiate low‐ and high‐grade gliomas
Daliang Liu, Guang Cheng, Xiaowei Ma, Shuai Wang, Xiaohu Zhao, Wei Zhang, Weidong Yang, Jing Wang
Abstract
Abstract Background and purpose To compare and characterize metabolic features of high‐ and low‐grade glioma tumors using 68 Ga‐PSMA‐617 and 18 F‐FDG positron emission tomography/computed tomography (PET/CT). Methods Thirty patients who underwent both 68 Ga‐PSMA‐617 and 18 F‐FDG PET/CT over 2 consecutive days and then underwent surgical treatment were retrospectively identified. All tumors were diagnosed histologically. This report includes 16 high‐grade glioma (HGG) and 14 low‐grade glioma (LGG) tumors. Standard uptake value (SUV) and target to nontarget (T/NT) were quantitatively investigated through the entire tumor region. Statistical analyses were performed using area under the curve (AUC) and comparison of two means. Results SUV max and SUV mean were the most effective (AUC, 0.96 and 0.94 for PSMA PET; AUC, 0.79 and 0.74 for FDG PET, respectively) for differentiating HGGs from LGGs. These methods distinguished between HGG and LGG effectively (PSMA PET: SUV max , 5.766 ± 3.945 vs. 0.7364 ± 0.5295, p < 0.0001; SUV mean , 1.666 ± 1.680 and 0.1514 ± 0.1534, p < 0.0001, respectively) (FDG PET: SUV max , 11.67 ± 3.639 and 9.118 ± 6.612; SUV mean , 5.648 ± 2.114 and 4.435 ± 2.872; p = 0.0083, 0.0262, respectively). The Youden index for SUV max and SUV mean of 68 Ga‐PSMA‐617 and 18 F‐FDG were 0.82 and 0.79 and 0.54 and 0.61, separately. T/NT max was helpful for visual inspection of 68 Ga‐PSMA‐617‐PET images (T/NT max : 1.291 ± 0.9553 in grade II, 5.25 ± 2.435 in grade III, and 13.61 ± 13.84 in grade IV). T/NT max differed significantly between LGG and HGG and between subtypes of LGG. Conclusion PET/CT with 68 Ga‐PSMA‐617 and 18 F‐FDG may help distinguish between HGG and LGG, and 68 Ga‐PSMA‐617 PET/CT is superior to 18 F‐FDG in differentiating HGG and LGG.