A Single Center Report on the Upgrade Rate of Radial Scar/Complex Sclerosing Lesions of the Breast

Abstract

Introduction: Radial scar/complex sclerosing lesion (RS/CSL) is a benign breast lesion. The incidence of RS/CSL on core needle biopsy (CNB) ranges from 0.6 to 3.7%. Despite benign pathology, the radiographic appearance of RS/CSL can be indistinguishable from invasive or in situ malignancy. The upgrade rate of RS/CSL to malignancy varies widely. Whether there are RS/CSL on CNB that may be safely observed without surgery is not well understood. Methods: We performed a single center retrospective study of females over 18 with radiology-pathology concordant diagnosis of RS/CSL on CNB from 2015–2020. We excluded patients with ipsilateral or contralateral invasive or in situ malignancy within 3 months prior to or after biopsy proven RS/CSL. Management was immediate surgical excision within 6 months or imaging surveillance. Upgrade rate was determined in the cohort of patients who underwent surgical excision based on evidence of in situ or invasive malignancy. Results: We identified 83 patients with RS/CSL; 56 (67%) underwent surgical excision and 27 (33%) underwent surveillance. Those who underwent surgical excision had a significant higher rate of breast cancer in the family (41% vs 15%, p = 0.02) and concurrent atypia on CNB (16% vs 0%, p = 0.03). After surgical excision, 11 cases upgraded to atypia and one case upgraded to ductal carcinoma in situ. There were no factors associated with upgrade to malignancy. Conclusion: Upgrade rates of RS/CSL to malignancy remain low; however a significant number upgrade to atypia, which offers relevant information for risk stratification. Further research is needed before omission of excision of RS/CSL can be safely considered.