Gallium-67/Gallium-68-[DFO]-octreotide-a potential radiopharmaceutical for PET imaging of somatostatin receptor-positive tumors: Synthesis and radiolabeling in vitro and preliminary in vivo studies

Journal Article · Tue Feb 01 04:00:00 EST 1994 · Journal of Nuclear Medicine Technology

OSTI ID:135838

Smith-Jones, P M; Stolz, B; Bruns, C ^[1]

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1. Institute of Nuclear Medicine, Univ. Hospital, Villigen (Switzerland); and others

When labeled with gamma-emitting radionuclides, somatostatin analogs have the potential to localize somatostatin receptor-positive tumors using gamma camera scintigraphy. The authors present a somatostatin analog, [DFO]-octreotide (SDZ 216-927), that comprises desferrioxamine B coupled to octreotide via a succinyl linker. This conjugate can be labeled with either {sup 67}Ga-labeled conjugate is stable in vitro to autoradiolysis over a 24-hr period. Rats bearing a somatostatin receptor-positive pancreatic islet cell tumor were injected with 20 MBq of {sup 67}Ga[DFO] octreotide (33 GBq {sup 67}Ga/{mu}mole). After 1 hr, the accumulation of {sup 67}Ga[DFO]-octreotide was 0.38 {plus_minus} 0.08 %ID/g and the tumor-to-nontumor ratios for blood, muscle, liver and intestine were 2.5, 7.4, 1.98 and 1.6, respectively. PET studies with {sup 68}Ga[DFO]-octreotide recorded a very rapid accumulation at the tumor and a subsequent residence half-life of about 6 hr. Gallium-68-[DFO]-octreotide can be used in PET studies to diagnose receptor-positive tumors such as gastroentero-pancreatic, small-cell lung and breast tumors. 40 refs., 7 figs., 3 tabs.

• OSTI ID: 135838
• Journal Information: Journal of Nuclear Medicine Technology, Journal Name: Journal of Nuclear Medicine Technology Journal Issue: 2 Vol. 35; ISSN JNMTB4; ISSN 0091-4916
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
55 BIOLOGY AND MEDICINE
BASIC STUDIES
CHEMICAL PREPARATION
LABELLING
NEOPLASMS
POSITRON COMPUTED TOMOGRAPHY
RADIOPHARMACEUTICALS
SCINTISCANNING
SOMATOSTATIN
TISSUE DISTRIBUTION