Age / Sex : 39 / F

Age / Sex :  39/F

Chief complaint :  Left ankle painful tender mass

Discussion

Findings:

1. Left ankle AP view shows soft tissue mass without calcification.

2. US shows a well defined hypoechoic oval soft tissue mass at inferior lateral area of the distal fibular tip, just lateral aspect of the peroneal tendon.

Hypervascularity on color and power Doppler US

Differential Diagnosis:

    Giant cell tumor of the tendon sheath

Diagnosis:  

Vascular leiomyoma (angioleiomyoma)

Discussion:

Angioleiomyomas are benign soft tissue tumors arising from the smooth muscle cells of blood vessels. These tumors are relatively infrequent and typically present as small (<2 cm), freely movable, painful masses. Although most frequently reported in the lower extremity and in middle-aged female patients, angioleiomyomas can be found throughout the body in male and female adults of all ages.

Although angioleiomyomas are relatively rare tumors, sonographic findings suggestive of angioleiomyomas include well-defined margins,hypervascularity, and a small size (<2 cm).

The vascular flow of these tumors has been described as showing high resistance, suggesting

the presence of muscular arteries.

 MRI of angioleiomyoma shows a well-demarcated subcutaneous mass of isointense signal on T1-weighted image, heterogenous high signal intensity on T2-weighted images with homogeneous good enhancement, and an adjacent tortuous vascular structures in soft tissue of the extremities.

When a slowly growing lower extremity mass has these features, particularly in proximity to major arteries or veins (containing smooth muscle), the diagnosis of angioleiomyoma should be

considered.

References:

1.     Smith J, Wisniewski SJ, Lee RA. Sonographic and clinical features of angioleiomyoma presenting as a painful Achilles tendon mass. J Ultrasound Med 2006;25:1365-1368

2.     Yoo HJ, Choi JA, Chung JH, et al. Angioleiomyoma in soft tissue of extremities: MRI findings. AJR2009;192:291-294