Malignant small-bowel neoplasms: spectrum of disease on MR imaging

Malignant neoplasms of the small bowel are among the rarest types of cancer, accounting for only 2% of all gastrointestinal neoplasms. Owing both to the intrinsic difficulty of common radiographic and endoscopic methods in visualising the entire small bowel and the lack of typical physical findings, a delay in diagnosis is common. Recently, magnetic resonance (MR) imaging has become a widely accepted imaging modality in the study of suspected small-bowel neoplasms due to its ability to depict, without exposure to ionising radiation and with excellent soft-tissue contrast, intraluminal disorders in conjunction with mural, extraparietal and regional abnormalities. The aim of this pictorial review is to illustrate the MR appearance of malignant small-bowel neoplasms.