In:
Contrast Media & Molecular Imaging, Hindawi Limited, Vol. 2018 ( 2018-06-20), p. 1-9
Kurzfassung:
Introductions . [ N -methyl-C-11] α -Methylaminoisobutyric acid (MeAIB) is an artificial amino acid radiotracer used for PET study, which is metabolically stable in vivo. In addition, MeAIB is transported by system A neutral amino acid transport, which is observed ubiquitously in all types of mammalian cells. It has already been shown that MeAIB-PET is useful for malignant lymphoma, head and neck cancers, and lung tumors. However, there have been no reports evaluating the usefulness of MeAIB-PET in the diagnosis of brain tumors. The purpose of this study is to investigate the efficacy of system A amino acid transport PET imaging, MeAIB-PET, in clinical brain tumor diagnosis compared to [S-methyl-C-11]-L-methionine (MET)-PET. Methods . Thirty-one consecutive patients (male: 16, female: 15), who were suspected of having brain tumors, received both MeAIB-PET and MET-PET within a 2-week interval. All patients were classified into two groups: Group A as a benign group, which included patients who were diagnosed as low-grade astrocytoma, grade II or less, or other low-grade astrocytoma ( n = 12 ) and Group B as a malignant group, which included patients who were diagnosed as anaplastic astrocytoma, glioblastoma multiforme (GBM), or recurrent GBM despite prior surgery or chemoradiotherapy ( n = 19 ). PET imaging was performed 20 min after the IV injection of MeAIB and MET, respectively. Semiquantitative analyses of MeAIB and MET uptake using SUVmax and tumor-to-contralateral normal brain tissue ( T / N ) ratio were evaluated to compare these PET images. ROC analyses for the diagnostic accuracy of MeAIB-PET and MET-PET were also calculated. Results . In MeAIB-PET imaging, the SUVmax was 1.20 ± 1.29 for the benign group and 2.94 ± 1.22 for the malignant group ( p 〈 0.005 ), and the T / N ratio was 3.77 ± 2.39 for the benign group and 16.83 ± 2.39 for the malignant group ( p 〈 0.001 ). In MET-PET, the SUVmax was 3.01 ± 0.94 for the benign group and 4.72 ± 1.61 for the malignant group ( p 〈 0.005 ), and the T / N ratio was 2.64 ± 1.40 for the benign group and 3.21 ± 1.14 for the malignant group ( n.s. ). For the analysis using the T / N ratio, there was a significant difference between the benign and malignant groups with MeAIB-PET with p 〈 0.001 . The result of ROC analysis using the T / N ratio indicated a better diagnosis accuracy for MeAIB-PET for brain tumors than MET-PET ( p 〈 0.01 ). Conclusions . MeAIB, a system A amino acid transport-specific radiolabeled agents, could provide better assessments for detecting malignant type brain tumors. In a differential diagnosis between low-grade and high-grade astrocytoma, MeAIB-PET is a useful diagnostic imaging tool, especially in evaluations using the T / N ratio. Clinical trial registration . This trial was registered with UMIN000032498 .
Materialart:
Online-Ressource
ISSN:
1555-4309
,
1555-4317
DOI:
10.1155/2018/1292746
Sprache:
Englisch
Verlag:
Hindawi Limited
Publikationsdatum:
2018
ZDB Id:
2222967-X
