Stomach, Forestomach - Angiectasis

Angiectasis (vascular ectasia) is primarily a spontaneous, age-related lesion. The cause is generally not known but occasionally can be a response to chemical injury. Angiectasis consists of widely dilated vascular spaces, especially capillaries (or sinusoids) and venules, that are lined by unremarkable endothelial cells. There is no apparent increase in numbers of vessels, and the stroma of the organ is unaltered. A differentiation between angiectasis and hemangioma should be attempted, although the difference between angiectasis and hemangioma often is not clear. Hemangiomas tend to be well-circumscribed unencapsulated masses composed of tightly packed dilated vascular spaces. Each vascular space is enclosed and lined by a single layer of normal-appearing endothelial cells aligned on collagenous septa, which are usually thin, although some have broad collagenous stromata. Angiectasis does not usually present as a well-circumscribed mass because the dilated vascular channels are often irregularly coursing through connective.