Table 2. Summary of typical and atypical imaging findings of small intestine neoplasms.

Histology	Typical appearance	Atypical appearance
Adenocarcinoma	Concentric lumen narrowing with irregular edges	Polypoid lesions with well-defined surface and margins
	Complete bowel obstruction	Central ulcerations
	Heterogenous enhancement	Duodenal localisation
Carcinoid	Small (<2 cm) single or multiple filling defects	Ill-defined thickening of bowel wall without discrete mass
	Desmoplastic reaction of the mesentery	Absence of desmoplastic reaction
	Hypervascular	Duodenal or jejunal localisation
Lymphoma	Coarse segmental wall thickening with ulceration and necrosis	Discrete polyp that may be a lead point of intussusception
	Bulky lymphyadenopathies	Absence of significant lymphoadenopathies
	Aneurysmal dilatation of bowel loops	No signs of bowel occlusion
GIST	Large regular mass with inhomogeneous enhancement	Irregular mass with low attenuation and poor enhancement
	Necrosis and/or ulceration	Larger calcifications
	Ileal localisation	Direct vascular encasement
Metastases	Intraluminal nodules develeloping from haematogenous spread to submucosal layers	Large serosal masses developed from intraperitoneal seeding from gastrointestinal cancers

GIST, gastrointestinal stromal tumour.