Korean J Radiol.  2011 Feb;12(1):44-51. 10.3348/kjr.2011.12.1.44.

Incidentally Detected Enhancing Breast Lesions on Chest Computed Tomography

• Lin WC
• Hsu HH
• Li CS
• Yu JC
• Hsu GC
• Yu CP
• Chang TH
• Huang GS

• KMID: 991681
• DOI: http://doi.org/10.3348/kjr.2011.12.1.44

Abstract

OBJECTIVE
To evaluate the nature and imaging appearance of incidental enhancing breast lesions detected on a routine contrast-enhanced chest CT.
MATERIALS AND METHODS
Twenty-three patients with incidental enhancing breast lesions on contrast-enhanced chest CT were retrospectively reviewed. The breast lesions were reviewed by unenhanced and enhanced CT, and evaluated by observing the shapes, margins, enhancement patterns and backgrounds of breast lesions. A histopathologic diagnosis or long-term follow-up served as reference standard.
RESULTS
Sixteen (70%) patients had malignant breast lesions and seven (30%) had benign lesions. In 10 patients, the breast lesions were exclusively detected on contrast-enhanced CT. Using unenhanced CT, breast lesions with fibroglandular backgrounds were prone to be obscured (p < 0.001). Incidental primary breast cancer showed an non-significant trend of a higher percentage irregular margin (p = 0.056). All of the four incidental breast lesions with non-mass-like enhancement were proven to be malignant.
CONCLUSION
Routine contrast-enhanced chest CT can reveal sufficient details to allow for the detection of unsuspected breast lesions, in which some cases may be proven as malignant. An irregular margin of incidental enhancing breast lesion can be considered a suggestive sign of malignancy.

Keyword

Breast; Chest; Computed tomography (CT); Incidental breast lesions

MeSH Terms

Aged
Breast Diseases/radiography
Breast Neoplasms/*radiography/secondary
*Contrast Media
Female
Humans
*Incidental Findings
Iohexol/*analogs & derivatives/diagnostic use
Middle Aged
*Radiography, Thoracic
*Tomography, X-Ray Computed

Figure

• 

  Fig. 1 72-year-old female patient underwent chest CT for staging of lymphoma. A. Contrast-enhanced CT showed focused image of regional non-mass-like enhancement in left breast (arrow); lesion was not detected on unenhanced CT. Lesion had fibroglandular tissue background. B. Craniocaudal view of left mammography showed cluster of microcalcification in upper inner quadrant of left breast (arrow). C. Sonography of left breast at corresponding location showed hypoechoic mass with ill-defined margin (long arrows) and microcalcifications (short arrow). At surgery, confirmed diagnosis was ductal carcinoma in situ.

• 

  Fig. 2 76-year-old female patient underwent chest CT for staging of tongue cancer. A. Contrast-enhanced CT showed right breast lesion with lobulated shape, irregular margin, and heterogeneous enhancement (arrow). Lesion had adipose tissue background. B. Sonography of right breast at corresponding location showed lobulated hypoechoic mass (arrows). Sonographically-guided core-needle biopsy confirmed diagnosis of invasive ductal carcinoma.

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