2017.06.01
Aquaporin Positron Emission Tomography Differentiates Between Grade III and IV Human Astrocytoma
（Neurosurgery. 2017 Jun 21. doi: 10.1093/neuros/nyx314. [Epub ahead of print]）
Suzuki Y1, Nakamura Y1, Yamada K1, Kurabe S1,2, Okamoto K2, Aoki H2, Kitaura H1,3, Kakita A3, Fujii Y2, Huber VJ1, Igarashi H1, Kwee IL4, Nakada T1.
1Center for Integrated Human Brain Science, Brain Research Institute.
2Department of Neurosurgery, Brain Research Institute.
3Department of Pathology, Brain Research Institute.
4Department of Neurology, University of California, Davis, USA.
Abstract
BACKGROUND: Aquaporin (AQP) water channels play a significant role in mesenchymal microvascular proliferation and infiltrative growth. AQPs are highly expressed in malignant astrocytomas, and a positive correlation is observed between their expression levels and histological tumor grade.
OBJECTIVE: To examine the utility of aquaporin positron emission tomography (PET) for differentiating between astrocytoma grade III and grade IV using the AQP radioligand [11C]TGN-020.
METHODS: Fifteen astrocytoma patients, grade III (n = 7) and grade IV (n = 8), and 10 healthy volunteers underwent [11C]TGN-020 aquaporin PET imaging. Surgical tissues of astrocytoma patients were examined for histopathological grading using the WHO classification standard and expression of AQP1 and AQP4 immunohistochemically.
RESULTS: Mean standardized uptake values of astrocytoma grade III and IV (0.51 ± 0.11 vs 1.50 ± 0.44, respectively) were higher than normal white matter (0.17 ± 0.02, P < .001) for both tumor grades. Importantly, mean standardized uptake values of astrocytoma grade IV were significantly higher than grade III (P < .01).
CONCLUSION: Our study demonstrated that [11C]TGN-020 aquaporin PET imaging differentiated between astrocytoma grades III and IV. We suggest its clinical application as a noninvasive diagnostic tool would lead to advancements in the management of these malignant brain tumors.
