Angiectasis can be associated with or secondary to other adrenal lesions such as inflammation, atrophy, degeneration, and neoplasia. It can also occur as a spontaneous age-related change in old rats and mice.
Angiectasis and hemangioma can be difficult to differentiate, but a distinction should be attempted. Hemangiomas tend to be well-circumscribed, unencapsulated masses composed of densely packed, dilated vascular spaces. The vascular spaces are lined by a single layer of normal-appearing endothelial cells aligned on usually delicate collagenous septa, though some cases exhibit more abundant collagenous stroma. In contrast, although angiectasis is also characterized by dilated vascular channels lined by unremarkable endothelium, the vascular channels are more loosely or irregularly arranged rather than presenting as a well-demarcated mass.
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