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.