Age / Sex : 63 / F

Elastofibroma dorsi

Discussion

Findings: Infrascapular region mass-like lesion with low SI on T1 & T2-WI (similar to surrounding muscle) and heterogeneous enhancement deep to serratus anterior and latissimus dorsi muscles

Differential Diagnosis: Fibromatosis, Metastasis, Liposarcoma

Diagnosis: Elastofibroma dorsi

Discussion:

 - Introduction:

1. Benign soft-tissue tumor with a characteristic location (infrascapular region; deep to the serratus anterior and latissimus dorsi musculature)

2. Unilateral masses have a slight right-sided predilection, but up to 60% of elastofibromas are bilateral

3. Most frequently seen in older women, with a reported female predilection of 5–13:1 and a mean age at diagnosis of 65–70 years

4. Often asymptomatic, up to 50% of patients, however, elastofibroma dorsi cause moderate pain and clicking, snapping, or clunking of the scapula with movement

5. Histologic analysis, composed of eosinophilic collagen bundles; groupings of mature adipocyte cells; and linear, globular, and stellate elastic fibers, findings that correspond to the thick fibrous bands and golden yellow fatty tissue seen at gross pathologic examination

- Imaging findings

 CT: Poorly defined soft-tissue mass with attenuation similar to that of the adjacent skeletal

 MR: Well-defined mass with fibrous tissue is isointense relative to skeletal muscle with both T1- and T2-WI, whereas the fatty tissue has high signal intensity with T1-WI. Contrast-enhanced images show both areas with and areas without enhancement

 US: Well-defined multilayered pattern of hypoechoic linear areas of fat deposition intermixed with echogenic fibroelastic tissue
 

References:

1. Ochsner JE, Sewall SA, Brooks GN et al. Best cases from the AFIP: Elastofibroma dorsi. Radiographics. 26 (6): 1873-6.

2. Naylor MF, Nascimento AG, Sherrick AD, McLeod RA. Elastofibroma dorsi: radiologic findings in 12 patients. AJR Am J Roentgenol 1996;167:683-687