Type:
Educational Exhibit
Keywords:
Breast, Mammography, MR, Ultrasound, Diagnostic procedure, Screening, Patterns of Care
Authors:
W. Pienaar, D. Taylor, E. Wylie; Perth, WA/AU
DOI:
10.26044/ranzcr2021/R-0408
Background
Contrast enhanced spectral mammography (CESM) is gaining popularity as an adjunct diagnostic tool in breast imaging, combining 2D digital mammography with the administration of intravenous contrast.
- It enables evaluation of lesion enhancement associated with neovascularity as a marker of clinically relevant breast disease, similar to MRI.
- It is of comparable sensitivity to breast MRI with a high negative predictive value and lower rate of false positive findings [1].
- It is accessible, affordable and time efficient with very few contra-indications.
- CESM is used in screening assessment and symptomatic breast clinics, pre-operative staging and monitoring response to neo-adjuvant chemotherapy in breast cancer patients.
- Further applications in post treatment imaging surveillance and breast screening are being explored and CESM biopsy has recently become commercially available.
- CESM will be included as a new data item in the BreastScreen Australia dictionary and added to the BreastScreen WA data collection from April 2021.
Radial scars are benign breast lesions of unknown cause characterised by central fibroelastotic cores with radiating spokes of ducts and lobules and a reported incidence of 14-28% in unselected autopsy series [2].
- With modern technological advances in imaging such as digital breast tomosynthesis (DBT) radial scars are more frequently encountered and now often the target of biopsy rather than an incidental finding in surgical specimens [1,2].
- Management of radial scars is challenging because of uncertainty regarding their malignant potential and the coexistence of radial scars with breast cancer and other high-risk lesions [1,2].
MR appearances of radial scars are described as
- distortion, irregular/round masses or foci (all with variable enhancement) or
- non-mass enhancement [2,3]
- absent/modest enhancement has a high negative predictive value for malignancy at excision [2]
- upgrade at excision is often associated with avid pre-operative contrast enhancement [2,3]
- non enhancement on MR does not exclude atypia [4]
While the appearances of radial scars on MRI have been well documented, little has been published regarding radial scars on CESM.
Two studies examined the utilisation of CESM in the post biopsy management of B3 lesions (including 5/42 radial scars) and in the assessment of architectural distortion [5,6].
These demonstrated a high negative predictive value of CESM for invasive malignancy in both B3 lesions and architectural distortion.
As with breast MRI, CESM can initiate second look breast ultrasound for subtle or incidental findings not identified on initial mammography or ultrasound, prompting review of radial scar ultrasound appearances in local practice.
Not all radial scars have ultrasound correlates with varying percentages of visibility reported in the literature (2,3).
Ultrasound appearances of radial scars are described, in order of decreasing frequency, as
- hypoechoic irregular masses with or without shadowing
- round or oval circumscribed lesions
- focal shadowing without discernible mass lesions [2,3]