Figure 11a. Angiolipoma in the subcutaneous thigh of a 21-year-old man. (a, b) Coronal T1-weighted (500/14) (a) and axial proton-density fat-suppressed (2000/30) (b) MR images show a subcutaneous mass that is largely isointense relative to fat (arrows). Several small nodular foci are also seen that have a more serpentine appearance (arrowheads), suggestive of vessels on the fat-suppressed MR image (b). (c) Photomicrograph (original magnification, x150; H-E stain) reveals a lipomatous mass (L) with more cellular areas peripherally (arrows). The more cellular peripheral area, shown in a higher power insert (original magnification, x400; H-E stain), contains multiple fibrin microthrombi in small-caliber vessels (arrowheads).