About the Cover
The αvβ3 integrin is a key player in angiogenesis and tumor metastasis. The cover image shows an immunohistochemical stain of αvβ3 expression on the endothelium of a microvessel in a pigmented villonodular synovitis. In the same lesion, αvβ3 expression could also be demonstrated noninvasively by positron emission tomography (PET) using the αvβ3 selective tracer [18F]Galacto-RGD. The authors demonstrate that [18F]Galacto-RGD PET successfully identifies the level of αvβ3 expression in man noninvasively. For further details, please see Beer et al. on page 3942.