TY - JOUR T1 - 1-<sup>11</sup>C-Acetate Versus <sup>18</sup>F-FDG PET in Detection of Meningioma and Monitoring the Effect of γ-Knife Radiosurgery JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 883 LP - 891 DO - 10.2967/jnumed.109.070565 VL - 51 IS - 6 AU - Ren-Shyan Liu AU - Chen-Pei Chang AU - Wen-You Guo AU - David H.C. Pan AU - Donald Ming-Tak Ho AU - Chi-Wei Chang AU - Bang-Hung Yang AU - Liang-Chi Wu AU - Shin-Hwa Yeh Y1 - 2010/06/01 UR - http://jnm.snmjournals.org/content/51/6/883.abstract N2 - This study aimed to define the potential of 1-11C-acetate PET, compared with 18F-FDG, in detecting meningiomas and monitoring the effect of γ-knife radiosurgery. Methods: Twenty-two patients with the neuroradiologic diagnosis of meningioma were examined by 1-11C-acetate and 18F-FDG PET on the same day. There were 12 cases of histopathologically proven meningioma (8 grade I, 2 grade II, and 2 grade III), 1 of tuberculous granuloma, and 1 of degenerative tissue. 1-11C-acetate PET scans of fasting patients were obtained 10 min after intravenous administration of 740 MBq of 1-11C-acetate. 18F-FDG PET was performed at 2 h after 1-11C-acetate scanning. The PET images were evaluated by a qualitative method and semiquantitative analysis using standardized uptake value and tumor-to-cortex ratio. Results: The 18F-FDG PET study revealed a hypometabolic focus in 17 meningiomas (8 grade I, 1 grade II, and 8 unknown grade) and hypermetabolism in 1 grade II and 2 grade III meningiomas. High uptake of 1-11C-acetate was observed in all 20 meningiomas, in contrast to the low uptake in surrounding normal brain tissue, allowing a clearer demarcation of the tumor boundary than that provided by 18F-FDG. Dissociation of regional accumulation of 1-11C-acetate and 18F-FDG within the tumor was also noted on the coregistered images. The standardized uptake value for 1-11C-acetate was not different from that for 18F-FDG (mean ± SD, 3.16 ± 1.75 vs. 3.22 ± 1.50, P = 0.601), but the tumor-to-cortex ratio for 1-11C-acetate was higher than that for 18F-FDG (3.46 ± 1.38 vs. 0.93 ± 1.08, P &lt; 0.005). 18F-FDG was able to differentiate grade I from grade II–III meningiomas, whereas 1-11C-acetate was unable to do so. Tuberculous granuloma had a high 1-11C-acetate and 18F-FDG uptake similar to that of grade II/III meningioma. Five patients received 1-11C-acetate and 18F-FDG PET before and after γ-knife surgery. 1-11C-acetate performed better than did 18F-FDG in monitoring the response of tumor metabolism to radiosurgery. Conclusion: 1-11C-acetate was found to be useful for detecting meningiomas and evaluating the extent of meningiomas and potentially useful for monitoring tumor response to radiosurgery. However, 1-11C-acetate was not useful for evaluating the tumor grade. 18F-FDG was found to be less useful than 1-11C-acetate for evaluating the extent of meningiomas and the response to radiosurgical treatment but may be useful for differentiating benign from malignant meningiomas. 18F-FDG and 1-11C-acetate are complementary for assessing diverse cell metabolism of meningioma. ER -