Fluorine-18-labeled fluoroboronophenylalanine PET in patients with glioma.

Abstract

UNLABELLED:

We synthesized fluorine-18-labeled fluoroboronophenylalanine (18F-10B-FBPA), an analog of boronophenylalanine (10B-BPA), and characterized its pharmacokinetics in patients with glioma. We conducted PET studies on three types of gliomas to clarify the relationship between tumor grade and each rate constant [K1 (ml/g/min), k2 (min[-1]) and k3 (min[-1])], and here, we discuss the metabolism of the 10B-BPA analog (18F-10B-FBPA).

METHODS:

Thirty-three cases of primary gliomas were studied by dynamic PET using DL-18F-10B-FBPA or L-18F-10B-FBPA. Dynamic PET images of 18F-10B-FBPA incorporation into tumors were obtained, and the arterial blood samplings were performed in all cases.

RESULTS:

When the dynamic PET data were represented as Gjedde-Patlak plots, there was a positive slope, suggesting the involvement of the putative metabolic pool of this tracer. A three-compartment model using rate constants (K1, k2 and k3) was used for the kinetic analysis. The accumulation of 18F-10B-FBPA was found to correlate with the degree of malignancy, and the L form of 18F-10B-FBPA was taken up better than was the DL form. The results of dynamic PET analysis suggested that K1 (measuring amino acid transport process) is a major factor determining the accumulation of 18F-10B-FBPA. A comparison of the rate constants revealed that k3 (metabolic process) did not correlate with the degree of malignancy. The absence of evident differences in k3 between DL and L forms suggests that k3 represents phenomena that are not dependent on the native form of L.

CONCLUSION:

These PET data will be of practical use for diagnosis of malignancy and direct prediction of the effectiveness of boron neutron capture therapy using 10B-BPA.

• Authors: Y Imahori, S Ueda, Y Ohmori, T Kusuki, K Ono, R Fujii, T Ido
• Journal: Journal of nuclear medicine : official publication, Society of Nuclear Medicine (J Nucl Med) Vol. 39 Issue 2 Pg. 325-33 (Feb 1998) ISSN: 0161-5505 [Print] United States
• PMID: 9476945 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Boron Compounds
• Fluorine Radioisotopes
• Radiopharmaceuticals
• 4-borono-2-fluorophenylalanine
• Phenylalanine
• 4-boronophenylalanine

Topics

• Astrocytoma (diagnostic imaging)
• Boron Compounds (pharmacokinetics)
• Brain Neoplasms (diagnostic imaging, physiopathology)
• Cerebrovascular Circulation
• Fluorine Radioisotopes
• Glioblastoma (diagnostic imaging)
• Glioma (diagnostic imaging, physiopathology)
• Humans
• Phenylalanine (analogs & derivatives, pharmacokinetics)
• Radiopharmaceuticals (pharmacokinetics)
• Tomography, Emission-Computed