Upgrade risk of image-targeted radial scar and complex sclerosing lesions diagnosed at needle-guided biopsy: a retrospective study.

OBJECTIVES

To determine the upgrade rate of radial scar (RS) and complex sclerosing lesions (CSL) diagnosed with percutaneous biopsy. The secondary objectives were to determine the new atypia rate after surgery and to assess the diagnosis of subsequent malignancy on follow-up.

METHODS

This single-institution retrospective study had IRB approval. All image-targeted RS and CSL diagnosed with percutaneous biopsy between 2007 and 2020 were reviewed. Patient demographics, imaging presentation, biopsy characteristics, histological report, and follow-up data were collected.

RESULTS

During the study period, 120 RS/CSL were diagnosed in 106 women (median age, 43.5 years; range, 23-74), and 101 lesions were analyzed. At biopsy, 91 (90.1%) lesions were not associated with another atypia or malignancy and 10 (9.9%) were associated with another atypia. Out of the 91 lesions that were not associated with malignancy or atypia, 75 (82.4%) underwent surgical excision, and one upgrade to low-grade CDIS was detected (1.3%). Among the 10 lesions initially associated with another atypia, 9 were surgically excised and no malignancy was detected. After a median follow-up of 47 months (range: 12-143 months), two (1.98%) developed malignancy in a different quadrant; in both cases, another atypia was present at biopsy.

CONCLUSION

We found a low upgrade rate on image-detected RS/CSL, with or without another atypia associated. Associated atypia was underdiagnosed at biopsy in almost one-third of cases. Subsequent cancer risk could not be established because the only two cases were associated with another high-risk lesion (HRL), which might have increased the patient's risk of developing malignancy.

CLINICAL RELEVANCE STATEMENT

Our upgrade rates of RS/CSL with or without atypia diagnosed with core needle biopsy are almost as low as the ones reported with larger sampling methods. This result has particular importance in places with limited accessibility to US-guided vacuum-assisted biopsy.

KEY POINTS

•New evidence is showing lower upgrade rates of RS and CSL after surgery, leading to a more conservative management with extensive sampling using VAB or VAE. •Our study showed only one upgrade to a low-grade DCIS after surgery, yielding an upgrade rate of 1.33%. •During follow-up, no new malignancy was detected in the same quadrant where RS/CSL was diagnosed, including patients without surgery.