Linked Life Data

20676727

Source:http://linkedlifedata.com/resource/pubmed/id/20676727

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2011-5-9
pubmed:abstractText
Increased tryptophan metabolism via the kynurenine pathway is a major mechanism of tumor immuno-resistance. ?-[(11)C]Methyl-L: -tryptophan (AMT) is a positron emission tomography (PET) tracer for tryptophan catabolism, and increased AMT uptake has been demonstrated in brain tumors. In this study we evaluated the use of AMT PET for detection of low-grade gliomas and glioneuronal tumors, and determined if kinetic parameters of AMT uptake can differentiate among tumor types. AMT PET images were obtained in 23 patients with newly diagnosed low-grade brain tumors (WHO grade II gliomas and WHO grade I dysembryoplastic neuroepithelial tumors [DNETs]). Kinetic variables, including the unidirectional uptake rate (K-complex) and volume of distribution (VD; which characterizes tracer transport), were measured using a graphical approach from tumor dynamic PET and blood-input data, and metabolic rates ([Formula: see text]) were also calculated. These values as well as tumor/cortex ratios were compared across tumor types. AMT PET showed increased tumor/cortex K-complex (n = 16) and/or VD ratios (n = 15) in 21/23 patients (91%), including 11/13 tumors with no gadolinium enhancement on MRI. No increases in AMT were seen in an oligodendroglioma and a DNET. Astrocytomas and oligoastrocytomas showed higher [Formula: see text] tumor/cortex ratios (1.66 ± 0.46) than oligodendrogliomas (0.96 ± 0.21; P = 0.001) and DNETs (0.75 ± 0.39; P < 0.001). These results demonstrate that AMT PET identifies most low-grade gliomas and DNETs by high uptake, even if these tumors are not contrast-enhancing on MRI. Kinetic analysis of AMT uptake shows significantly higher tumor/cortex tryptophan metabolic ratios in astrocytomas and oligoastrocytomas in comparison with oligodendrogliomas and DNETs.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1573-7373
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
102
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
409-15
pubmed:dateRevised
2011-10-6
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Differential kinetics of ?-[¹¹C]methyl-L-tryptophan on PET in low-grade brain tumors.
pubmed:affiliation
PET Center, Children's Hospital of Michigan, Wayne State University School of Medicine, 3901 Beaubien Blvd., Detroit, MI 48201, USA. juhasz@pet.wayne.edu
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural