Per Skaane MD, PhD, Presenter: Equipment support, Hologic, Inc Support, Hologic, Inc

Randi Gullien RT, Abstract Co-Author: Support, Hologic Inc Travel support, Hologic, Inc

Ellen B. Eben MD, Abstract Co-Author: Support, Hologic, Inc

Unni Haakenaasen MD, Abstract Co-Author: Support, Hologic, Inc

Ingvild Ness Jebsen, Abstract Co-Author: Support, Hologic, Inc

Mona Krager MD, Abstract Co-Author: Support, Hologic, Inc

Jon Lomo MD, Abstract Co-Author: Nothing to Disclose

Radial scar is a benign lesion presenting with distortion or spiculations on mammography that mimic cancer. Diagnosis requires open surgical biopsy. The purpose of the study was to analyse the number of mammographic findings later confirmed as radial scars on excisional biopsy in mammography screening comparing full-field digital mammography (FFDM) and combined FFDM plus digital breast tomosynthesis (DBT).

From Nov 22, 2010 to Dec 31, 2012 (one screening round), a total of 34,742 women attended an organized population-based screening program, of which 25,547 (73.5%) underwent FFDM plus DBT. All exams (bilateral CC and MLO views) were prospectively interpreted by 4 independent readers using a 5-point rating scale for probability of cancer. The trial had 4 arms: Arm A FFDM only; Arm B FFDM plus CAD; Arm C FFDM plus DBT; and Arm D synthetic 2D plus DBT. Women with distortion suspected by at least one of the 4 independent readers were discussed at arbitration meeting before decision to recall for assessment or not. Diagnostic work-up included additional mammographic views, ultrasound, MRI as problem-solver, and needle biopsy or diagnostic surgical biopsy, if indicated. Open surgical biopsy was carried out in women with highly suspicious distortion when malignancy was not confirmed at needle biopsy.

A total of 31 radial scars were diagnosed at open surgery. One case having only FFDM (no DBT) was excluded in the comparison. Thus, at total of 30/25,547 (0.12%) of screened women with radial scar (“a false positive mammographic finding”) underwent surgical biopsies. In the 4 reading arms, the number of positive scores in these 30 women were: Arm A=7 (23%), Arm B=10 (33%), Arm C=25 (83%), and Arm D=23 (77%).

Radial scars (“complex sclerosing lesions”) are much better demonstrated on tomosynthesis than on FFDM and consequently these lesions will be more commonly found using DBT. Breast lesions presenting as highly suspicious distortions need open surgical biopsy if needle biopsy does not confirm malignancy. The problem is, however, minor and diagnostic surgical biopsy was only necessary in 0.12% of women in this study.

The benefits of tomosynthesis in breast cancer screening including higher cancer detection rates outweigh the adverse effect of false positive mammographic findings caused by radial scars.

Skaane, P, Gullien, R, Eben, E, Haakenaasen, U, Jebsen, I, Krager, M, Lomo, J, Radial Scar: A Diagnostic Challenge in Breast Cancer Screening Using Tomosynthesis.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13016491.html