IN-111 OCTREOTIDE SCINTIGRAPHY IN NEUROFIBROMATOSIS

Scintigraphy with the radiolabelled somatostatin analogue indium-111-D TPA-D-Phe-1-octreotide has recently been proposed for the imaging of C NS neoplasms expressing somatostatin receptors. While meningiomas are imaged with high sensitivity, neurinomas do not take up octreotide owi ng to the lack of somatostatin receptors, Neurofibromatosis is a relat ively uncommon disorder in which meningiomas and neurinomas often occu r in the same patient. Differential diagnosis between these two tumour s by computed tomography and magnetic resonance imaging can be difficu lt, This study reports on In-111-octreotide scintigraphy in four patie nts with neurofibromatosis. In-111-octreotide scintigraphy was shown t o be very helpful in the in vivo differential diagnosis: all four meni ngiomas showed intense tracer uptake, while all 15 neurinomas were neg ative (P<0.001 by Fisher's exact test). It may be concluded that scint igraphy with In-111-octreotide is a useful diagnostic procedure in neu rofibromatosis, complementing standard neuroradiological imaging proce dures.