title: Evaluation of brain tumors using dynamic 11C-methionine-PET.
abstract: The aim of this study is to assess whether dynamic imaging of (11)C-methionine (MET) uptake on positron emission tomography (PET) is useful for the differential diagnosis of brain tumor histology. Regional MET uptake in static brain PET scans from three consecutive phases (5-15, 15-25, and 25-35 min) after intravenous injection were measured in 144 patients with brain tumors. Regions of interest (ROI) were placed in the pituitary gland, confluence, choroid plexus, coronal radiation, brainstem, frontal cortex, parietal cortex, cerebellum, and brain tumors. The standard uptake value (SUV) of the ROIs in the normal brain structures and brain tumors were measured, and the mean MET SUV region/normal frontal lobe cortex uptake ratio (R/N ratio) of the normal brain structures and the maximum MET SUV tumor/normal frontal cortex uptake ratio (T/N ratio) were evaluated semi-quantitatively. There were significant dynamic declines of the mean MET R/N ratio in the normal pituitary gland and confluence; however, there were significant dynamic increases in white matter. Significant dynamic decrease of the maximum MET T/N ratio was seen in meningiomas and oligodendrocytic tumors, whereas significant dynamic increase was seen in glioblastomas and malignant lymphomas. Dynamic changes of MET uptake vary significantly with the normal brain structures and brain tumor histology. These results suggest that MET-PET may be useful in the differential diagnosis of brain tumors.
authors.affiliation: Chubu Medical Center for Prolonged Traumatic Brain Dysfunction, Kizawa Memorial Hospital, 630 Shimo-kobi, Kobi-cho, Minokamo, Gifu, 505-0034, Japan. akitatsuki@yahoo.co.jp
authors.forename: Tatsuki
authors.initials: T
authors.lastname: Aki
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Nakayama
authors.forename: Shingo
authors.initials: S
authors.lastname: Yonezawa
authors.forename: Syunsuke
authors.initials: S
authors.lastname: Takenaka
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Miwa
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Asano
authors.forename: Jun
authors.initials: J
authors.lastname: Shinoda
authors.forename: Hirohito
authors.initials: H
authors.lastname: Yano
authors.forename: Toru
authors.initials: T
authors.lastname: Iwama
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D002250:Carbon Radioisotopes; D005260:Female; D006801:Humans; D008297:Male; D008715:Methionine; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011379:Prognosis; D019275:Radiopharmaceuticals
chemical_list: D002250:Carbon Radioisotopes; D019275:Radiopharmaceuticals; C086242:carbon-11 methionine; D008715:Methionine