Histopathological comparison between endofibrosis of the high-performance cyclist and atherosclerosis in the external iliac artery

Stenosis (%) of external iliac arteries of controls and patients (p < .0001). Horizontal line indicates the median value.

Histological comparison between endofibrosis and atherosclerosis in the external iliac artery. A and C, Hematoxylin and eosin (H&E) stainings of endofibrotic lesion in a professional cyclist. A, Overview of the wall of the artery showing the media (m) and the endofibrotic lesion (e). Bar = 250 μm. C, Higher magnification of the endofibrotic lesion showing a loose connective tissue matrix with moderate to high cellularity consisting of spindle and stellate shaped cells. The cells are not orderly arranged. Bar = 100 μm. B and D, H&E stainings of atherosclerotic lesion. B, Overview of the wall of the artery showing the media (m) and the atherosclerotic plaque. The plaque consists of an extracellular atheroma (a), a socalled shoulder with macrophages (s) and a fibrous cap (c). Bar = 250 μm. D, Higher magnification of the fibrous cap of the atherosclerotic plaque showing low cellularity with spindle cells arranged in bundles. The extra cellular matrix consists of densely-packed collagen. Bar = 100 μm.

Macrophages in endofibrotic lesion. A, Endofibrotic lesion with moderate to high cellularity. Foam cells are present near the lumen at the top of the photo. B, CD68 immunohistochemical staining in adjacent section, identifying the cells as macrophage foam cells (brown staining). Bar = 125 μm.