Betty Tuong MD, Presenter: Nothing to Disclose

Supriya Ravindra Kulkarni MD, DMRD, Abstract Co-Author: Nothing to Disclose

Derek Muradali MD, Abstract Co-Author: Nothing to Disclose

Abnormal screening mammograms are often further evaluated with spot compression views. If the abnormality does not persist on spot views, it is usually presumed that the lesion was artifactual from overlapping normal tissue, and the assessment is deemed negative. However, there is a trend to perform breast ultrasound (US) despite a negative mammographic work-up. The objective of this study was to determine if the addition of US after negative spot views could detect breast cancers missed at initial assessment.

Retrospective chart review was performed from 2004 to 2013. Patients with abnormal mammograms, negative follow-up spot views, and concomitant breast US were identified. Abnormalities detected on US and the final BIRADS classification were reviewed. Pathology from BIRADS 4/5 cases was recorded. Follow-up imaging recommended after a benign biopsy or BIRADS 3 assessment were reviewed to a final diagnosis of benign or cancer.

1860 patients were enrolled with US classified as BIRADS 1/2 (1588), BIRADS 3 (210) or BIRADS 4/5 (62). Of the BIRADS 4/5 cases, patients were initially referred for asymmetry (32), focal asymmetry (16), architectural distortion (8) or a mass (6). US showed a region of shadowing (26) or a mass (36). Final pathology was invasive ductal carcinoma (7), invasive lobular carcinoma (1), DCIS (2), fibrocystic change (10), fibroepithelial lesion (5), radial scar (2), fat necrosis (2), papillary lesion (2) and benign breast tissue (31). In total, 10/1860 (0.5%) cases had a final diagnosis of cancer. For benign biopsies, follow-up was recommended for up to 2 years and initiated 61 additional studies (23 US, 21 MRI and 17 mammograms). For BIRADS 3 cases, 213 additional studies were performed for up to 3 years (113 US, 1 MRI and 99 mammograms). 274 additional studies were performed in total and all cases were benign at the completion of follow-up.

In patients with negative spot views at assessment, the prevalence of a mammographically occult cancer that can be detected by US is very low. The addition of US results in a substantial number of unnecessary biopsies and imaging tests. Therefore, in patients with negative spot views at assessment, an additional US should not be performed routinely.

It appears that on a population basis, more harm than good is caused by the addition of breast ultrasound after a negative mammographic work-up.

Tuong, B, Kulkarni, S, Muradali, D, Breast Ultrasound After A Normal Mammographic Work-up: More Harm than Benefit.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14001952.html