title: [11C]methionine quantitation in cancer PET studies.
abstract: Quantitation of the uptake of positron emitting tracers in cancer patients is still unsettled. A uniform method is needed for comparison of results and for collecting a data base of tumor PET studies. We have measured the tumoral uptake of [11C]methionine in 46 cancer patients using four different methods of analysis. The accumulation of [11C]methionine at 35-40 min after the injection adjusted to the injected dose and body surface area turned out to give similar results as a more complicated method where the uptake rate of [11C]methionine from the plasma to the tumor was calculated (r = 0.92, p less than 0.0001). The results suggest that in clinical [11C]methionine PET studies, 40 min emission scanning with frequent blood sampling is unnecessary. Only a single 5 min emission scan 25-40 min after the injection is required for analysis if the accumulation is adjusted to the injected dose and body surface area.
authors.affiliation: Department of Oncology and Radiotherapy, Turku University Central Hospital, Finland.
authors.forename: S
authors.initials: S
authors.lastname: Leskinen-Kallio
authors.forename: R
authors.initials: R
authors.lastname: Huovinen
authors.forename: K
authors.initials: K
authors.lastname: Någren
authors.forename: P
authors.initials: P
authors.lastname: Lehikoinen
authors.forename: U
authors.initials: U
authors.lastname: Ruotsalainen
authors.forename: M
authors.initials: M
authors.lastname: Teräs
authors.forename: H
authors.initials: H
authors.lastname: Joensuu
mesh_terms: D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism / Q000556:secondary; D002250:Carbon Radioisotopes; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000378:metabolism / Q000556:secondary; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000000981:diagnostic imaging / Q000378:metabolism; D008715:Methionine / Q000493:pharmacokinetics*; D009369:Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism; D009442:Neurilemmoma / Q000000981:diagnostic imaging / Q000378:metabolism; D014055:Tomography, Emission-Computed
chemical_list: D002250:Carbon Radioisotopes; D008715:Methionine