title: Imaging bone and soft tissue tumors with the proliferation marker [18F]fluorodeoxythymidine.
abstract: OBJECTIVE
  We have determined the ability of positron emission tomography (PET) with the thymidine analogue 3'-deoxy-3'[18F]fluorothymidine (FLT) to detect manifestation sites of bone and soft tissue tumors, to assess tumor grading, and to differentiate malignant from benign tumors.
  
  
  METHODS
  In this prospective bicenter trial, FLT-PET was done in 22 patients with established or suspected soft or bone tissue lesions. Routine diagnostic procedures included incisional biopsy, magnetic resonance imaging, and/or contrast-enhanced spiral computed tomography in all patients and [18F]fluorodeoxyglucose (FDG)-PET in 15 patients. Forty-five to 60 minutes after i.v. injection of 350 to 425 MBq FLT, emission and transmission scanning was done. Tracer uptake in the tumor was evaluated semiquantitatively by calculation of mean and maximum standardized uptake values (FLT-SUV) and compared with respective values of FDG. Results were correlated to histopathology and tumor grading.
  
  
  RESULTS
  FLT-PET detected all malignant bone or soft tissue tumors (17 of 17). Mean FLT-SUV in benign lesions was 0.7 (range, 0.3-1.3), and 1.3 in low-grade sarcoma (grade 1; range, 1.0-1.6), 4.1 (range, 2.2-6.0; P = 0.002) and 6.1 (range, 2.5-8.3; P = 0.001) in grade 2 and grade 3 tumors, respectively. FLT but not FDG uptake correlated significantly with tumor grading (r = 0.71 versus r = 0.01), and a cutoff value of 2.0 for FLT-SUV discriminated between low- and high-grade tumors.
  
  
  CONCLUSIONS
  In this clinical study, the proliferation marker FLT was suitable for imaging malignant bone or soft tissue tumors. FLT but not FDG uptake correlated significantly with the tumor grade, suggesting FLT as superior PET tracer for noninvasive grading of sarcomas.
authors.affiliation: Department of Nuclear Medicine, Technische Universitat Munchen, Munich, Germany. andreas.buck@tum.de
authors.forename: Andreas K
authors.initials: AK
authors.lastname: Buck
authors.forename: Ken
authors.initials: K
authors.lastname: Herrmann
authors.forename: Christian Meyer Zum
authors.initials: CM
authors.lastname: Büschenfelde
authors.forename: Malik E
authors.initials: ME
authors.lastname: Juweid
authors.forename: Mark
authors.initials: M
authors.lastname: Bischoff
authors.forename: Gerhard
authors.initials: G
authors.lastname: Glatting
authors.forename: Gregor
authors.initials: G
authors.lastname: Weirich
authors.forename: Peter
authors.initials: P
authors.lastname: Möller
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Wester
authors.forename: Klemens
authors.initials: K
authors.lastname: Scheidhauer
authors.forename: Tobias
authors.initials: T
authors.lastname: Dechow
authors.forename: Christian
authors.initials: C
authors.lastname: Peschel
authors.forename: Markus
authors.initials: M
authors.lastname: Schwaiger
authors.forename: Sven N
authors.initials: SN
authors.lastname: Reske
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D005462:Fluorine Radioisotopes / Q000493:pharmacokinetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012983:Soft Tissue Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D013936:Thymidine / Q000493:pharmacokinetics
chemical_list: D005462:Fluorine Radioisotopes; D019275:Radiopharmaceuticals; D013936:Thymidine