Radiology of infiltrating angiolipoma

Infiltrating angiolipomas are rare benign soft-tissue neoplasms that are locally aggressive and require wide surgical excision. Of 10 patients studied, five showed serpiginous densities intermixed with fat on plain films. Six radionuclide bone scans showed uptake by the soft-tissue lesion. Eight angiograms demonstrated poorly marginated, very hypervascular lesions. Computed tomography (CT) in five patients yielded excellent visualization of predominantly low density lesions that invaded and replaced skeletal muscle. The combination of angiography and CT indicated the specific diagnosis and demonstrated the size, extent, and vascularity of the tumors.