Noninvasive differentiation of meningiomas from other brain tumours using combined 111Indium-octreotide/99mtechnetium-DTPA brain scintigraphy.

Abstract

We have studied prospectively 47 patients with CNS tumours including 16 meningiomas and 33 other tumours using combined 111In-octreotide and 99mTc-DTPA brain scintigraphy. 111In-octreotide scintigraphy was used to image somatostatin receptors (SSR) and 99mTc-DTPA scintigraphy was used to assess the integrity of the blood-brain barrier (BBB). A total of 32 tumours (65%) were detected. All SSR positive tumours also had positive 99mTc-DTPA scans and all SSR negative tumours were negative on 99mTc-DTPA scans. Among the tumours located outside the BBB, all meningiomas and two out of six schwannomas were positive on combined SSR/99mTc-DTPA scintigraphy. Among the tumours located inside the BBB, seven out of nine gliomas grade I-III were negative, whereas all glioblastomas were positive. Other positive tumours included one malignant non-Hodgkin lymphoma and two cerebral metastases. SSR scintigraphy alone was non-specific in the diagnosis of meningiomas, as 16 non-meningiomatous tumours also had positive SSR scans probably due to a breakdown of the BBB (excluding the malignant lymphoma). Measuring the tumour-to-background ratio on SSR scans improved specificity, but sensitivity was decreased below 70% because some meningiomas were only slightly positive. Only the ratio of SSR scintigraphy to conventional 99mTc-DTPA brain scintigraphy (SSR-to-BS index) allowed a reliable differentiation of meningiomas from other CNS tumours, most notable from schwannomas (sensitivity: 94%; specificity: 100%). Our results support the usefulness of combined SSR and conventional brain scintigraphy in the noninvasive pre-operative diagnosis of meningiomas.

• Authors: A Barth, A R Haldemann, J C Reubi, N Godoy, H Rösler, J A Kinser, R W Seiler
• Journal: Acta neurochirurgica (Acta Neurochir (Wien)) Vol. 138 Issue 10 Pg. 1179-85 ( 1996) ISSN: 0001-6268 [Print] Austria
• PMID: 8955437 (Publication Type: Journal Article)

Chemical References

• Receptors, Somatostatin
• indium-111-octreotide
• Octreotide
• Technetium Tc 99m Pentetate

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Blood-Brain Barrier (physiology)
• Brain Neoplasms (diagnostic imaging, surgery)
• Diagnosis, Differential
• Female
• Humans
• Male
• Meningeal Neoplasms (diagnostic imaging, surgery)
• Meningioma (diagnostic imaging, surgery)
• Middle Aged
• Octreotide (analogs & derivatives)
• Radionuclide Imaging
• Receptors, Somatostatin (analysis)
• Sensitivity and Specificity
• Technetium Tc 99m Pentetate