Tracers for the detection of brain tumors
It follows that a higher percentage of tumors could be detected with radioisotopes if tumorspecific tracers were available, and it seemed possible that an injected fatty acid might show an affinity for brain tumors but would be unable to penetrate the blood-brain barrier in normal brain.
Abstract
~ I A N Y DIFFERENT radioactive tracers are in use for the detection of brain tumors. All are able to escape from the blood into tumors, but they are less able to penetrate the blood-brain barrier in normal brain, and so reveal tumors not because they accumulate preferentially in tumor tissue, but because they are partially blocked from entering the surrounding brain.].? It follows that a higher percentage of tumors could be detected with radioisotopes if tumorspecific tracers were available. To date, attempts to discover such specific tracers, which concentrate highly in tumor tissue and not in normal brain and other normal tissues, have not been successfuL--j To our knowledge, no one has tested the ability of a radioisotopically labeled lipid to lodge preferentially in brain tumors. For several reasons, it seemed possible that an injected fatty acid might show an affinity for brain tumors but would be unable to penetrate the blood-brain barrier in normal brain. When compared with normal brain, on the