ABSTRACT
The PET tracer 5-([11C]methyloxy)-L-tryptophan (5-(11)CMTP) was prepared by nucleophilic fluorination and alkylation reaction via a two-step procedure in order to develop specific tumor probe. The biodistribution and microPET imaging of 5-(11)CMTP were executed. The results unveiled that the overall radiochemical yield with no decay correction was (14.6 ±7.2) %, the radiochemical purity was more than 95% and high uptake and long retention time of 5-(11)CMTP in liver, kidney and blood were observed but low uptake in brain and muscle were found, furthermore, high uptake of 5-(11)CMTP in tumor tissue was observed. It seems that 5-(11)CMTP will be a potential amino acid tracer for tumors imaging with PET.
Subject(s)
Neoplasms/diagnostic imaging , Positron-Emission Tomography , Tryptophan , Amino Acids , Animals , Radioactive Tracers , Tissue Distribution , Tryptophan/analogs & derivativesABSTRACT
OBJECTIVE: To study the biodistribution of L-[S-methyl-(11)C]-methioine ((11)C-MET) and explore its clinical application in positron emission tomography (PET) for brain tumor detection. METHODS: Twenty-four Wistar rats and divided into 6 equal groups and injected with (11)C-MET through the tail vein and killed by decollation at 5, 10, 20, 30 and 40 min after injection, respectively. The liver, brain, blood, heart, lung, kidney, and spleen were harvested to measure the radioactivity and calculate the biodistribution of (11)C-MET. PET imaging with (11)C-MET was performed in 6 normal volunteers and 30 patients with pathologically confirmed brain gliomas. RESULTS AND CONCLUSION: (11)C-MET showed high blood uptake and a long retention in the tumor mass, therefore can be a valuable tracer for PET imaging of brain tumor and the hypophysis.
