title: Comparison of 3'-deoxy-3'-[18F]fluorothymidine PET and O-(2-[18F]fluoroethyl)-L-tyrosine PET in patients with newly diagnosed glioma.
abstract: OBJECTIVE
  The purpose of this prospective study was to clarify the value of FLT PET and FET PET for the noninvasive grading and prognosis of newly diagnosed gliomas.
  
  
  METHODS
  Twenty patients with newly diagnosed gliomas were investigated with FLT and FET PET before surgery. FLT and FET uptakes were assessed by the maximum standardized uptake (SUVmax) of tumor, and the ratio to uptake in the normal brain parenchyma (TNR). All tumors were graded by WHO system.
  
  
  RESULTS
  FLT PET detected all 17 high-grade gliomas (HGG) and did not detect all 3 low-grade gliomas (LGG). FET PET detected all 20 HGG and LGG regardless of grading. The average FLT SUVmax in HGG and LGG was 1.51 ± 0.72 and 0.30 ± 0.07, and the average FLT TNR in HGG and LGG was 5.52 ± 3.09 and 1.12 ± 0.14, respectively. The differences of FLT SUVmax and TNR between HGG and LGG were statistically significant (p=0.0069, p=0.0070). The average FET SUVmax in HGG and LGG was 2.68 ± 0.86 and 1.36 ± 0.15, and the average FET TNR in HGG and LGG was 2.31 ± 0.73 and 1.27 ± 0.12, respectively. The differences of FET SUVmax and TNR between HGG and LGG were statistically significant (p=0.0129, p=0.0095).
  
  
  CONCLUSIONS
  FET PET has higher sensitivity in detection of gliomas rather than FLT PET, but it seems that FLT PET is better than FET PET for noninvasive grading and predicting prognosis of newly diagnosed gliomas, considering high contrast of FLT and overlap of FET uptakes between HGG and LGG.
authors.affiliation: Department of Nuclear Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 108, Pyung-Dong, Jongno-Gu, Seoul, 110-746, South Korea. suyoung.jeong@samsung.com
authors.forename: Su Young
authors.initials: SY
authors.lastname: Jeong
authors.forename: Sang Moo
authors.initials: SM
authors.lastname: Lim
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D015224:Dideoxynucleosides; D005260:Female; D005910:Glioma / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D011446:Prospective Studies; D014443:Tyrosine / Q000031:analogs & derivatives*
chemical_list: D015224:Dideoxynucleosides; C117289:O-(2-fluoroethyl)tyrosine; D014443:Tyrosine; C002854:alovudine