Table 4 Imaging characteristic features for gastrointestinal lesions associated with NF1
From: Spectrum of gastrointestinal lesions of neurofibromatosis type 1: a pictorial review
GI lesions type | General characteristic features | Imaging characteristic features for CT scan and MRI | Differential diagnosis | ||
|---|---|---|---|---|---|
True neurogenic neoplasms | neurofibromas | -Homogenously hypo attenuating round or tubular masses | - Characteristically low signal intensity on T1-w - Heterogeneous high signal intensity on T2-w: • High T2 signal: pathological areas of cystic - degeneration or normal myxoid matrix • The low T2 signal: collagen and fibrous tissue - Areas of lowT2 signal enhance following - gadolinium administration | - Digestive schwannomas - Neurinomas - Neuroendocrine tumour - GIST | |
Plexiform neurofibromas | -Nodules or infiltrating lesions – Extension from the root of the mesentery to the wall of the intestine – iso or hypoattenuating | Ring-like or septated pattern Rope-like gross appearance | - Pathognomonic | ||
Multiple nerve sheath tumour | Heterogeneous in CT attenuation and MR signal intensity (necrosis++) Enhancement pattern is typically heterogeneous Borders of the tumour are often irregular and infiltrative | - Plexiform neurfibroma | |||
GIST | - Younger age - Multiple lesions - Asymptomatic - No overexpression of KIT or PDGFRA | - No particularity | - No particularity | – | |
Neuroendocrine tumours | - More frequent particularly in black population - Younger age of presentation - Same range of malignancy as general population - Always arise in or near the ampulla of Vater - Somatostatin secretion - Rarely symptomatic - Association with pheochromocytoma and duodenal carcinoids in NF1 | - No particularity | - No particularity | – | |
GI tract vasculopathy | - Not before age 5O -Affects aorta and its main branches | -Arteriovenous malformations - Vascular stenosis and post-stenotic aneurysm -Stenosis usually involves multiples territories - Aneurysms do not occur in two different circulatory regions | Athrosclerosis | ||
Adenocarcinoma Embryonal tumour | Association with NF1 controversed | - No particularity | No particularity | ||