title: [99mTc-octreotide receptor scintigraphy in NCI-H446 small cell lung cancer nude mice model].
abstract: BACKGROUND
  For highly aggressive small cell lung cancer (SCLC), early diagnosis is important for its prognosis, but the current inspection methods are more limited, with poor specificity of the traditional imaging methods, and the high cost of PET/CT, difficult to popularization and application. SCLC is kind of neuroendocrine tumors, high expression of somatostatin receptors, which is the cornerstone of its early molecular imaging diagnosis. The aim of this study is to observe the biodistribution and metabolism of 99mTc-octreotide in normal and the human SCLC bearing nude mice.
  
  
  METHODS
  Dynamic and static scintigraphy at 0.5 h, 2 h, 3 h, 4 h were performed in both normal and tumor bearing nude mice after intravenous injection of 99mTc-octreotide. The technique of drawing region of interest (ROI) was used to obtain the averaged pixel counts and the activity-time (A-T) curve of brain, heart, lung, liver, kidney, tumor, respectively.
  
  
  RESULTS
  ① The biodistribution study in normal nude mice showed highest uptake in kidney and liver, lower in lung and heart, lowest in brain. Most 99mTc-octreotide was excreted via kidney. ② All tumors were displayed clearly at 3 h postinjection of 99mTc-octreotide. The averaged T/N ratio at 0.5 h, 2 h, 3 h, 4 h postinjection of 99mTc-octreotide was 1.163 ± 0.03, 2.08 ± 0.12, 3.03 ± 0.23, 2.689 ± 0.31, respectively (F=51.69, P<0.000,1). The radioactivity of tumor was lower than liver, and similar with the lung. The curve of tumor showed a radioactivity peak at 2 min-3 min postinjection.
  
  
  CONCLUSIONS
  99mTc-octreotide receptor imaging on nude mice bearing SCLC shares high positive rate, especially at 3 h postinjection.
authors.affiliation: Department of Nuclear Medicine, the Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Li
authors.affiliation: Department of Nuclear Medicine, the Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China.
authors.forename: Shuyao
authors.initials: S
authors.lastname: Zuo
authors.affiliation: Department of Nuclear Medicine, the Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China.
authors.forename: Xufu
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Nuclear Medicine, the Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China.
authors.forename: Xinfeng
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Nuclear Medicine, the Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China.
authors.forename: Guoming
authors.initials: G
authors.lastname: Wang
authors.affiliation: Department of Nuclear Medicine, the Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China.
authors.forename: Fengyu
authors.initials: F
authors.lastname: Wu
mesh_terms: D000818:Animals; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000378:metabolism; D008297:Male; D051379:Mice; D008819:Mice, Nude; D015282:Octreotide / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D015609:Organotechnetium Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000008:administration & dosage / Q000493:pharmacokinetics*; D017481:Receptors, Somatostatin / Q000737:chemistry* / Q000378:metabolism; D055752:Small Cell Lung Carcinoma / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000378:metabolism
chemical_list: C493098:99mTc-octreotide; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin; D015282:Octreotide