Korean J Radiol.  2013 Oct;14(5):711-717. 10.3348/kjr.2013.14.5.711.

Band-Like Interposing Fat along Large Vessels: Ultrasonographic Pseudolesions of the Breast

• Kang BJ
• Kim HS
• Cha ES
• Lee JH
• Park CS
• Jung NY
• Whang IY
• Kim SH
• Choi JJ
• Lee A

• KMID: 1711423
• DOI: http://doi.org/10.3348/kjr.2013.14.5.711

Abstract

OBJECTIVE
The aim of this study is to evaluate the clinical characteristics and ultrasonographic findings of band-like interposing fat as well as to identify additional approaches for its diagnosis.
MATERIALS AND METHODS
This study included 26 confirmed cases of band-like interposing fat from June 2008 to June 2010. A retrospective analysis was performed to evaluate the clinical characteristics and ultrasonographic findings in these cases. Five radiologists analyzed the ultrasonographic findings, which correlated with the mammographic and MRI findings when available, according to Breast Imaging Reporting and Data System classification.
RESULTS
None of the 26 patients had any symptoms. In 92.3% of the patients, the lesion was located in the upper outer quadrant of the breast. The mean distance of the lesion from the nipple was 2.4 +/- 0.7 cm (1.1-4.5). The mean depth of the lesion from the skin was 1.3 +/- 0.3 cm (0.8-2.1). The mean maximal length of the lesion was 0.8 +/- 0.4 cm (0.3-1.8). The following were the most frequent ultrasonographic findings of lesions: irregular shape, not parallel orientation, indistinct margins, abrupt interface, hypoechogenicity, no posterior feature, no calcification, and presence of vascularity. The most frequent BI-RADS category was 4a. There were no suspicious findings on the mammography or MRI.
CONCLUSION
Ultrasonographic findings may lead to misclassification of band-like interposing fat as a malignancy. A better understanding of the clinical and ultrasonographic characteristics of band-like interposing fat would facilitate its differentiation from a true mass.

Keyword

Breast mass; Ultrasonography; Fatty tissue

MeSH Terms

Adipose Tissue/*ultrasonography
Adult
Biopsy, Fine-Needle
Breast Diseases/pathology/*ultrasonography
Diagnosis, Differential
Diagnostic Errors
Female
Humans
Mammary Arteries/*ultrasonography
Middle Aged
Pregnancy
Retrospective Studies
Ultrasonography, Mammary/*methods
Young Adult

Figure

• 

  Fig. 1 Band-like interposing fat mimicking malignancy in 36-year-old woman. (A) Transverse, (B) longitudinal, and (C) color Doppler breast ultrasonography. All five radiologists interpreted lesion as malignant. Ultrasound results for this lesion were irregular shape, not parallel orientation, spiculated margins, echogenic halo, hypoechoic, shadowing, no calcification, vascularity, and category 4c. D. Microscopic findings show medium-sized vessel (arrow) in background fat and loose fibrous tissue (HE stain, × 100).

• 

  Fig. 2 Band-like interposing fat showing typical findings in 58-year-old woman. (A) Transverse, (B) longitudinal, and (C) color Doppler breast ultrasonography. Ultrasonographic results including irregular shape, not parallel orientation, angular margins, abrupt lesion boundary, hypoechoic, no posterior feature, macrocalcification, vascularity, and category 4a were selected by 3 or more of the 5 reviewers. (D) T2-weighted MRI of breast shows normal interposing fat in left breast (arrow). (E) Microscopic findings show thick vascular wall (arrow) of large-sized vessel in background fat (HE stain, × 100).

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