Related Experiment Video
Updated: Jul 16, 2026
A Practical Guide for the Production and PET/CT Imaging of 68Ga-DOTATATE for Neuroendocrine Tumors in Daily Clinical Practice
Published on: April 17, 2019
Somatostatin receptor scintigraphy in surveillance of pediatric brain malignancies
Geetika Khanna1, M Sue O'Dorisio, Yusuf Menda
1Department of Radiology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA. geetika-khanna@uiowa.edu
Insights
Somatostatin receptor scintigraphy (SRS) aids in distinguishing brain tumors from scar tissue after treatment. SRS is a valuable tool for surveillance, especially when MRI results are unclear.
Area of Science:
- Pediatric oncology
- Neuroimaging
- Nuclear medicine
Background:
- Somatostatin receptor scintigraphy (SRS) is utilized for imaging pediatric brain tumors (PBTs).
- Functional imaging like SRS may better differentiate PBTs from scar or necrosis post-treatment.
- This study retrospectively assesses SRS's role in PBT post-treatment surveillance.
Purpose of the Study:
- To evaluate the efficacy of SRS in the surveillance of pediatric brain tumors after treatment.
- To compare the sensitivity and specificity of SRS and MRI in detecting tumor recurrence or necrosis.
- To determine the correlation between somatostatin receptor expression and SRS findings.
Main Methods:
- Twenty children with known brain malignancies underwent serial SRS and MRI.
- Patient outcome served as the reference standard for comparing SRS and MRI sensitivity/specificity.
- Immunohistochemistry (IHC) was used to determine somatostatin receptor (sstr) expression in tumor specimens.
Main Results:
- SRS demonstrated high accuracy, with true positive results in 15 of 16 patients with confirmed disease.
- MRI was equivocal in two cases, unable to distinguish tumor recurrence from radiation necrosis, where SRS was positive.
- SRS correctly identified all patients with no evidence of disease and showed high concordance with IHC-confirmed sstr-positive tumors.
Conclusions:
- SRS is a valuable adjunct to MRI for post-treatment surveillance of sstr-positive PBTs.
- SRS is particularly useful when MRI findings are equivocal in differentiating tumor recurrence from necrosis.
- The study highlights SRS's effectiveness in managing PBTs after initial treatment.
Background:
Somatostatin receptor scintigraphy (SRS) has been successfully used in imaging PBTs and, as a functional imaging modality, may be better able to differentiate tumor from scar/necrosis. This retrospective study evaluates the role of SRS in post-treatment surveillance of PBTs.
Procedure:
Twenty children (age range: 7 months to 24 years, mean: 9 years) with known brain malignancies underwent serial SRS and MRI. The sensitivity and specificity of SRS and MRI were compared for surveillance scanning using patient outcome as the reference standard. Somatostatin receptors (sstrs) expression was determined by immunohistochemistry (IHC) of available tumor specimens.
Results:
SRS was true positive (TP) in 15 of 16 patients with proven disease found post-resection (n = 5) or during follow-up (n = 11). In contrast, MRI was positive in 12 of these 16 patients and equivocal in another two patients where it could not distinguish between radiation necrosis and tumor recurrence. The two patients with false negative (FN) MRI and proven disease were positive by SRS. SRS was negative in all four patients with no evidence of disease by follow-up (mean follow-up = 58 months). The only patient with a FN SRS (TP by MRI) was one without IHC evidence of sstrs. SRS was TP in 7/7 tumors with IHC documented sstrs.
Conclusions:
SRS is a useful adjunct to MRI for post-treatment surveillance of sstr-positive PBTs, particularly when MRI is equivocal.
