Figure 10.

Abdominal fibromatosis: a 65-year-old male with a slowly growing painless suprapubic mass. (a) Axial CT and T1 (TE13/TR643) fat saturation image postcontrast reveal a well-defined soft-tissue mass (arrows) in the lower left rectus abdominis that displaces the bladder to the right. Lesion attenuation on CT is higher than skeletal muscle reflecting higher collagen component. An area of necrosis (curved arrow in (b)) is noted in the posterior aspect of the lesion. Lesion margins and heterogeneous enhancement are better appreciated on MR. (c) Coronal T1-weighted (TE11/TR427) and (d) STIR (TE78/TR4810) sequences show the lesion (arrows) with mildly ill-defined borders, mild peripheral edema, and band-like areas (arrowheads) of low signal within the lesion. (e) Photograph of the sectioned gross specimen, resected after radiation therapy, reveals a large area of central necrosis (arrowheads).