Panel Disdussion

3rd International Congress of of Nuclear Medicine & & 15th 15th Iranian Annual Annual Congress of
Congress of Nuclear Medicine
Shahid Beheshti Shahid Beheshti University University of Medical of Medical Sciences Sciences 19-21 19-21 May May 2011
The role of 99mTc-EDDA/HYNIC-TATE(Octreotate) in the
evaluation of solitary pulmonary nodule (SPN)
Kamran Aryana
Mashhad University of Medical Sciences
Introduction: Solitary pulmonary nodule (SPN) radiologically
defined as a single lesion that is less than 3cm in diameter, surround
by lung parenchyma and not associated with adenopathy or
atelectasis. Those SPNs that do not meet specific benign criteria are
considered indeterminate and need to further evaluation. Tc99m-
Octreotate is a somatostatin analogue that binds with high affinity to
somatostatin receptors.
Objective: Initial experience to assess the usefulness of 99mTc-
Octreotate in the differential diagnosis of incidentally discovered SPN
and to determinate the cut off value that would discriminate between
benign and malignant nodules.
Methods: 15 pulmonary nodules, with sized 1.2-3cm, were
evaluated in 14 patients (8 male and 6 female) aged 22-70yrs (mean
47 yrs). An activity of 740MBq of the Tc99m-Octreotate was injected
intravenously in each patient. Imaging was started 2 h post injection,
a static image (500 counts) and a SPECT acquisition was obtained
from the chest.
Results: The SPECT was true positive in 7/8 malignant SPNs.
Negative scintigraphic results were found in 4 Pt’s with benign SPN.
Two Pt’s with positive scan have infectious process (false positive).
Definitive diagnosis was obtained in all of patients by
histopathologiocal result or clinical and CT follow up.
Conclusion: Our study demonstrated that Tc99m-Octreotate is a
sensitive imaging modality with significant specificity and negative
predictive value when compared with CT. We recommend this scan
for the evaluation of SPNs, especially when PET is not available
before biopsy.
Keywords: Octreotate, Solitaire pulmonary nodule
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