Comparison of 2-amino-[3-¹¹C]isobutyric acid and 2-deoxy-2-[¹⁸F]fluoro-D-glucose in nude mice with xenografted tumors and acute inflammation.
OBJECTIVE
2-Deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) accumulates in tumors and also during active inflammation, including therapy-related inflammation. Additional PET tracers that are less avid to inflammation could be useful in differentiating cancer from inflammation and could complement the limitation of [18F]FDG-PET. 2-Amino-[3-11C]isobutyric acid ([3-11C]AIB) is a potential PET tracer for this purpose. We compared [3-11C]AIB and [18F]FDG uptakes in tumors and acute inflammation in a mouse model.


METHODS
Acute inflammatory lesions were induced in the hind legs of tumor-bearing mice by intramuscular injection of turpentine, and we conducted biodistribution and dynamic PET studies on [3-11C]AIB and [18F]FDG.


RESULTS
[3-11C]AIB tumor uptake increased with time and was statistically significantly higher than [18F]FDG uptake. In inflamed muscles, [3-11C]AIB uptake was statistically significantly lower than [18F]FDG uptake, and the tumor-to-inflammation ratio for [3-11C]AIB was statistically significantly higher than that for [18F]FDG.


CONCLUSIONS
[3-11C]AIB accumulates more selectively in tumor tissue than does [18F]FDG and thus has the potential of discriminating between tumors and inflammatory lesions better and of complementing the limitation of [18F]FDG.
Diagnostic Imaging Program, Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan. a_tsuji@nirs.go.jp
Atsushi B
AB
Tsuji
Koichi
K
Kato
Aya
A
Sugyo
Maki
M
Okada
Hitomi
H
Sudo
Chisato
C
Yoshida
Hidekatsu
H
Wakizaka
Ming-Rong
MR
Zhang
Tsuneo
T
Saga
D000208:Acute Disease; D000621:Aminoisobutyric Acids / Q000493:pharmacokinetics*; D000818:Animals; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic; D004355:Drug Stability; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D006801:Humans; D007249:Inflammation / Q000000981:diagnostic imaging / Q000378:metabolism; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D008297:Male; D051379:Mice; D008819:Mice, Nude; D049268:Positron-Emission Tomography; D055752:Small Cell Lung Carcinoma / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*
D000621:Aminoisobutyric Acids; D019788:Fluorodeoxyglucose F18; C100049:2-aminoisobutyric acid