Korean J Radiol.  2011 Oct;12(5):641-645. 10.3348/kjr.2011.12.5.641.

MRI of a Subcutaneous Myolipoma in the Ankle: a Case Report

• Lee YS
• Park SE
• Lee JU
• Choi ES

• KMID: 1116453
• DOI: http://doi.org/10.3348/kjr.2011.12.5.641

Abstract

Myolipoma is a rare benign tumor, composed of irregularly admixed adipose tissue and smooth muscle fibers. Few literature studies have described the radiologic appearance of myolipoma, especially in the soft tissue. No MRI findings in subcutaneous myolipoma of an extremity have been reported. Here, we report on the case of a 34-year-old woman with myolipoma in the subcutaneous tissue of the ankle and describe MRI features of the lesion.

Keyword

Myolipoma; Ankle; Subcutaneous tissue; Magnetic resonance

MeSH Terms

Adult
*Ankle
Female
Humans
Lipoma/*diagnosis/pathology
*Magnetic Resonance Imaging
Muscle, Smooth/pathology
Soft Tissue Neoplasms/*diagnosis/pathology
Subcutaneous Fat/pathology

Figure

• 

  Fig. 1 Myolipoma of subcutaneous region at ankle in 34-year-old woman. A. Axial T1-weighted image shows soft tissue mass (arrows) in subcutaneous region at level of posteromedial ankle joint. B, C. Coronal T1-weighted image (B) and T2-weighted image (C) show that this mass is lobulated in contour with some septations and hyperintense T1 and T2 signal intensity (asterisks). Medial peripheral portion of mass demonstrates intermediate T1 and T2 signal intensity (arrows). D. Coronal fat suppressed T2-weighted image shows significant signal loss of lobulated mass (asterisks) with no fat suppression of peripheral portion of mass (arrows). E, F. Enhanced fat suppressed T1 coronal (E) and axial (F) images demonstrate that main portion of mass shows fat suppression with no remarkable enhancement (asterisks); however, peripheral portion of mass shows heterogeneous enhancement (arrows). G. At gross pathologic examination, tumor is completely encapsulated with yellow to light pink appearance. H, I. Histologic analysis demonstrates variable admixture of smooth muscle (white arrow) and mature adipose tissue (black arrow) (Hematoxylin & Eosin staining; H, × 100; I, × 200).

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