Methionine (MET) is an essential α-amino acid which plays a role in several biochemical processes, such as biosynthesis of proteins.
L-Methionine labeled with 11C acts as a positron emission tomography tracer, as it is involved in synthesis of proteins in brain tumors.
Normal brain tissue recognizes only glucose as a metabolic substrate (thus having a very low physiological 11C-methionine uptake), whereas tumoral brain tissues present an increased 11C-methionine uptake. This makes the signal-to-noise ratio quite high, thus helping in reading and interpreting PET scans.
11C-Methionine PET is easy and fast to perform. Usually 370–740 MBq of tracer is injected intravenously and, because of the short half-life of 11C-labeled molecules (20 min), the uptake time ranges from only 10–30 min.
11C-Methionine PET is a useful diagnostic and therapeutic tool in neuro-oncology. It has a high sensitivity in identifying primary brain tumors (histologic grading, define the extent of tumor, identify optimal biopsy sites), metastases, recurrence, plan radiotherapy and response to therapy. Additionally it allows the study of myocardial infarction, hyperparathyroidism, squamous cell head and neck cancer, multiple myeloma, and lymphoma.
Keywords11C-Methionine Brain tumors Myeloma Lymphoma Hyperparathyroidism Squamous cell head and neck cancer
Blood brain barrier
Biological target volume
Focal cortical dysplasia
Fluid-attenuated inversion recovery
Gross tumor volume
Squamous cell head and neck cancer
High-performance liquid chromatography
L-type amino acid transporter
Non-small cell lung cancer
Response assessment in neuro-oncology
Standardized uptake value
Thin layer chromatography
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