title: Comparison of Diagnostic Sensitivity and Quantitative Indices Between (68)Ga-DOTATOC PET/CT and (111)In-Pentetreotide SPECT/CT in Neuroendocrine Tumors: a Preliminary Report.
abstract: OBJECTIVE
  In-pentetreotide has been used for neuroendocrine tumors expressing somatostatin receptors. Recently, (68)Ga-DOTATOC PET has been used with the advantage of high image quality. In this study, we compared quantitative indices between (111)In-pentetreotide SPECT/CT and (68)Ga-DOTATOC PET/CT.
  
  
  METHODS
  Thirteen patients diagnosed with neuroendocrine tumors were prospectively recruited. Patients underwent (111)In-pentetreotide scans with SPECT/CT and (68)Ga-DOTATOC PET/CT before treatment. The number and location of lesions were analyzed on both imaging techniques to compare lesion detectability. Additionally, the maximal uptake count of each lesion and mean uptake count of the lungs were measured on both imagings, and target-to-normal lung ratios (TNR) were calculated as quantitative indices.
  
  
  RESULTS
  Among 13 patients, 10 exhibited lesions with increased uptake on (111)In-pentetreotide SPECT/CT and/or (68)Ga-DOTATOC PET/CT. Scans with SPECT/CT detected 19 lesions, all of which were also detected on PET/CT. Moreover, 16 additional lesions were detected on PET/CT (6 in the liver, 9 in the pancreas and 1 in the spleen). PET/CT exhibited a significantly higher sensitivity than SPECT/CT (100 % vs. 54 %, P < 0.001). TNR was significantly higher on PET/CT than on SPECT/CT (99.9 ± 84.3 vs. 71.1 ± 114.9, P < 0.001) in spite of a significant correlation (r = 0.692, P = 0.01).
  
  
  CONCLUSIONS
  Ga-DOTATOC PET/CT has a higher diagnostic sensitivity than (111)In-pentetreotide scans with SPECT/CT. The TNR on PET/CT is higher than that of SPECT/CT, which also suggests the higher sensitivity of PET/CT. (111)In-pentetreotide SPECT/CT should be used carefully if it is used instead of (68)Ga-DOTATOC PET/CT.
authors.affiliation: Department of Nuclear Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744 Korea.
authors.forename: Inki
authors.initials: I
authors.lastname: Lee
authors.affiliation: Department of Nuclear Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744 Korea.
authors.forename: Jin Chul
authors.initials: JC
authors.lastname: Paeng
authors.affiliation: Department of Nuclear Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744 Korea.
authors.forename: Soo Jin
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Chan Soo
authors.initials: CS
authors.lastname: Shin
authors.affiliation: Department of Surgery, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Jang
authors.affiliation: Department of Nuclear Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744 Korea ; Cancer Research Institute, Seoul National University, Seoul, Korea.
authors.forename: Gi Jeong
authors.initials: GJ
authors.lastname: Cheon
authors.affiliation: Department of Nuclear Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744 Korea ; Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Gyeonggi-Do, Korea.
authors.forename: Dong Soo
authors.initials: DS
authors.lastname: Lee
authors.affiliation: Department of Nuclear Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744 Korea ; Cancer Research Institute, Seoul National University, Seoul, Korea.
authors.forename: June-Key
authors.initials: JK
authors.lastname: Chung
authors.affiliation: Department of Nuclear Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744 Korea ; Cancer Research Institute, Seoul National University, Seoul, Korea.
authors.forename: Keon Wook
authors.initials: KW
authors.lastname: Kang
keywords: 111In-pentetreotide; 68Ga-DOTATOC; Neuroendocrine tumors; Positron emission tomography; Single-photon emission-computed tomography