Uptake of 18F-Fluorocholine, 18F-FET, and 18F-FDG in C6 gliomas and correlation with 131I-SIP(L19), a marker of angiogenesis.

Abstract

UNLABELLED:

Targeting extracellular structures that are involved in angiogenic processes, such as the extra domain B of fibronectin, is a promising approach for the diagnosis of solid tumors. The aim of this study was to determine uptake of the (18)F-labeled PET tracers (18)F-fluorocholine (N,N-dimethyl-N-(18)F-fluoromethyl-2-hydroxyethylammonium), (18)F-fluoro-ethyl-l-tyrosine (FET), and (18)F-FDG in C6 gliomas of the rat and to correlate it with uptake of the anti-extra domain B antibody (131)I-SIP(L19) as a marker of neoangiogenesis.

METHODS:

C6 gliomas were orthotopically induced in 17 rats. Uptake of all tracers was measured using quantitative autoradiography, and uptake of (18)F-fluorocholine, (18)F-FET, and (18)F-FDG was correlated with uptake of (131)I-SIP(L19) on a pixelwise basis.

RESULTS:

The mean (131)I-SIP(L19), (18)F-fluorocholine, (18)F-FET, and (18)F-FDG standardized uptake values in the tumor and the contralateral normal cortex (in parentheses) were 0.31 +/- 0.22 (not detectable), 2.00 +/- 0.53 (0.49 +/- 0.07), 3.67 +/- 0.36 (1.42 +/- 0.22), and 7.23 +/- 1.22 (3.64 +/- 0.51), respectively. The (131)I-SIP(L19) uptake pattern correlated best with (18)F-fluorocholine uptake (z = 0.80, averaged z-transformed Pearson correlation coefficient) and (18)F-FET uptake (z = 0.79) and least with (18)F-FDG (z = 0.37).

CONCLUSION:

One day after intravenous injection, (131)I-SIP(L19) displayed a very high tumor-to-cortex ratio, which may be used in the diagnostic work-up of brain tumor patients. Of the 3 investigated (18)F tracers, (18)F-fluorocholine and (18)F-FET correlated better with the pattern of (131)I-SIP(L19) uptake than did (18)F-FDG. Whether this means that (18)F-fluorocholine and (18)F-FET are better suited than (18)F-FDG to monitor antiangiogenic therapy should be investigated in future studies.

• Authors: Matthias T Wyss, Nicolas Spaeth, Gregoire Biollaz, Jens Pahnke, Patrizia Alessi, Eveline Trachsel, Valerie Treyer, Bruno Weber, Dario Neri, Alfred Buck
• Journal: Journal of nuclear medicine : official publication, Society of Nuclear Medicine (J Nucl Med) Vol. 48 Issue 4 Pg. 608-14 (Apr 2007) ISSN: 0161-5505 [Print] United States
• PMID: 17401099 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antibodies
• Fibronectins
• O-(2-fluoroethyl)tyrosine
• Radiopharmaceuticals
• Recombinant Fusion Proteins
• SIP(L19) fusion protein
• Tyrosine
• fluorocholine
• Choline

Topics

• Animals
• Antibodies
• Brain Neoplasms (diagnosis, pathology)
• Cell Line, Tumor
• Choline (analogs & derivatives, pharmacokinetics)
• Fibronectins (chemistry)
• Glioma (diagnosis, pathology)
• Male
• Neovascularization, Pathologic
• Radiopharmaceuticals (pharmacokinetics)
• Rats
• Rats, Wistar
• Recombinant Fusion Proteins (pharmacokinetics)
• Tyrosine (analogs & derivatives, pharmacokinetics)