title: The utility of two somatostatin analog radiopharmaceuticals in assessment of radiologically indeterminate pulmonary lesions.
abstract: OBJECTIVE
  The aim of our study was to assess diagnostic accuracy of Tc-99m depreotide and Tc-99m-EDDA/HYNIC-TOC scintigraphy for evaluation of pulmonary lesions that appeared ambiguous on computed tomography (CT).
  
  
  METHODS
  Forty-nine consecutive patients (37 men and 12 women; mean age, 60 ± 11 years) with 60 pulmonary lesions on chest radiography and CT were referred for nuclear imaging. They were prospectively allocated to undergo whole-body scintigraphy (WBS) and single photon emission computed tomography (SPECT) using either Tc-99m depreotide (26 patients, group 1) or Tc-99m-EDDA/HYNIC-TOC imaging (23 patients, group 2). Histologic findings after tissue biopsy served as a gold standard for determining diagnostic accuracy of the 2 somatostatin analogs. Visual assessment was complemented by semiquantitative analysis based on target to background ratio.
  
  
  RESULTS
  Among the 32 pulmonary lesions scanned with Tc-99m depreotide, focal uptake was increased in 22 of 25 malignancies, whereas no uptake was found in 6 of 7 benign lesions (88% sensitivity, 85% specificity, and 88% accuracy) on both WBS and SPECT. Imaging of 28 pulmonary lesions with Tc-99m-EDDA/HYNIC-TOC had a similar diagnostic yield (sensitivity 87%, specificity 84%, and accuracy 86%). Overall, target to background ratios were higher on SPECT than WBS but not significantly different between groups 1 and 2 (SPECT 2.72 ± 0.70 vs. 2.71 ± 0.50, WBS 1.61 ± 0.32 vs. 1.62 ± 0.28, respectively).
  
  
  CONCLUSIONS
  This study demonstrates that Tc-99m depreotide and Tc-99m-EDDA/HYNIC-TOC have similar diagnostic value for characterizing pulmonary lesions that appear ambiguous on CT.
authors.affiliation: Faculty of Medicine, University of Belgrade, Serbia. dsobic@eunet.rs
authors.forename: Dragana P
authors.initials: DP
authors.lastname: Sobic-Saranovic
authors.forename: Smiljana V
authors.initials: SV
authors.lastname: Pavlovic
authors.forename: Vera M
authors.initials: VM
authors.lastname: Artiko
authors.forename: Djordjije Z
authors.initials: DZ
authors.lastname: Saranovic
authors.forename: Emilija D
authors.initials: ED
authors.lastname: Jaksic
authors.forename: Dragan
authors.initials: D
authors.lastname: Subotic
authors.forename: Ljudmila
authors.initials: L
authors.lastname: Nagorni-Obradovic
authors.forename: Nebojsa
authors.initials: N
authors.lastname: Kozarevic
authors.forename: Nebojsa
authors.initials: N
authors.lastname: Petrovic
authors.forename: Isidora T
authors.initials: IT
authors.lastname: Grozdic
authors.forename: Vladimir B
authors.initials: VB
authors.lastname: Obradovic
mesh_terms: D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013004:Somatostatin / Q000031:analogs & derivatives*
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C487389:technetium 99m EDDA-HYNIC-Tyr(3)-octreotide; D013004:Somatostatin; C444119:technetium Tc 99m depreotide