Extramural venous invasion by gastrointestinal malignancies: CT appearances.

The purpose of this article is to describe and demonstrate the appearances of extramural vascular invasion on computed tomography in gastrointestinal malignancies as one of the pathways of disease spread. In this article, we demonstrate the imaging features with pathologically proven examples, along with a brief description of relevant vascular anatomy. We shall also discuss the clinical significance and prognostic implications of extramural vascular invasion in gastrointestinal malignancies.