title: 3-[123I]Iodo-alpha-methyl-L-tyrosine uptake in cerebral gliomas: relationship to histological grading and prognosis.
abstract: 3-[123I]Iodo-alpha-methyl-L-tyrosine (IMT) is employed clinically as a tracer of amino acid transport in brain tumours using single-photon emission tomography (SPET). This study investigates the role of IMT SPET in the non-invasive histological grading and prognostic evaluation of cerebral gliomas. The files of patients investigated by IMT SPET in our clinic between 1988 and 1996 were evaluated retrospectively. Complete follow-up was available for 58 patients with cerebral gliomas investigated by IMT SPET shortly after tumour diagnosis. Seventeen patients had low-grade gliomas (WHO grade II), 14 had anaplastic gliomas (WHO grade III) and 27 had glioblastomas (WHO grade IV). Thirty-six cases were primary tumours and 22 cases, recurrences. Maximal and mean tumour-to-brain (T/B) ratios of IMT uptake at the first IMT SPET investigation were related to histological grading and survival time. Patients with low-grade gliomas showed significantly longer survival than patients with high-grade (grade III or IV) tumours. Gliomas without contrast enhancement on computed tomography or magnetic resonance imaging scans were associated with longer patient survival than tumours with contrast enhancement. The T/B ratios of IMT SPET showed no differences in relation to histological grading [WHO grade II: 1.73+/-0.59; WHO grade III: 1.74+/-0.38; WHO grade IV: 1.59+/-0.35, (mean+/-SD, T/B ratios of mean tumour uptake)]. The median survival time of patients with a high T/B ratio on IMT SPET was not significantly different from that of patients with a low T/B ratio (T/B ratio <1.6, 14.8 months; T/B ratio > or =1.6, 13.0 months). Thus, no evidence could be found for a relationship between IMT uptake in cerebral gliomas and either histological grading or survival time. Nevertheless, IMT SPET constitutes a useful method for the detection of primary and recurrent gliomas, determination of tumour extent and individual follow-up.
authors.affiliation: Clinic of Nuclear Medicine, Heinrich-Heine-University Düsseldorf, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Schmidt
authors.forename: U
authors.initials: U
authors.lastname: Gottwald
authors.forename: K J
authors.initials: KJ
authors.lastname: Langen
authors.forename: F
authors.initials: F
authors.lastname: Weber
authors.forename: A
authors.initials: A
authors.lastname: Hertel
authors.forename: F
authors.initials: F
authors.lastname: Floeth
authors.forename: J
authors.initials: J
authors.lastname: Felsberg
authors.forename: G
authors.initials: G
authors.lastname: Reifenberger
authors.forename: H H
authors.initials: HH
authors.lastname: Coenen
authors.forename: H W
authors.initials: HW
authors.lastname: Müller-Gärtner
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D005260:Female; D005910:Glioma / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008781:Methyltyrosines; D008875:Middle Aged; D011379:Prognosis; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D015996:Survival Rate; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D007457:Iodine Radioisotopes; D008781:Methyltyrosines; D019275:Radiopharmaceuticals; C030855:3-iodo-alpha-methyltyrosine