Somatostatin receptor scintigraphy in brain tumors and pituitary tumors: First experiences

This preliminary study embraced 45 patients with meningiomas, brain tumors or pituitary tumors, which were imaged by planar and tomographic scintigraphy after intravenous injection of 111Indium-labeled octreotide. In all of the meningiomas studied (unifocal and multifocal tumors in various locations), a high density of somatostatin receptors was detected by scintigraphy. Pituitary tumors were slightly positive in 50% of cases only, independent of the endocrine activity. Gliomas with an intact blood-brain barrier showed no enhanced tracer uptake in vivo, while gliomas with distributed blood-brain barrier had a high activity uptake. We conclude that in vivo somatostatin receptor scintigraphy, although not tumor-specific, may aid in the preoperative diagnosis and staging of intracranial tumors, especially skull base tumors. (orig.)