Outcome of radial scar/complex sclerosing lesion associated with epithelial proliferations with atypia diagnosed on breast core biopsy – Results from a multicentric UK based study

Abstract

AIMS: The clinical significance of radial scar/complex sclerosing lesion (RS/CSL) with high risk lesions (epithelial atypia) diagnosed on needle core biopsy (NCB) is not well defined. We aimed at assessing the upgrade rate to carcinoma in-situ (DCIS) and invasive on the surgical excision specimen in a large cohort of RS/CSL associated with atypia. METHODS: 161 women with NCB diagnosis of a RS/CSL with atypia and follow-up histology were studied. Histological findings including different forms of the atypical lesions and final histological outcome in the excision specimens were retrieved and analysed and the upgrade rate for malignancy and invasive carcinoma calculated. RESULTS: 76% of the cases were associated with an atypical ductal hyperplasia (ADH) whereas lobular neoplasia was seen in 24%. On final histology 38 cases were malignant (overall upgrade rate of 25%); 12 invasive and 27 DCIS. The upgrade differed according to the type of atypia and was highest for ADH (35%). When associated with lobular neoplasia the upgrade rate was 12%. The upgrade rates variability was also considerably lower and showing less variability when considering the upgrade to invasive carcinoma alone. CONCLUSION: The upgrade rate for ADH diagnosed on NCB with RS is similar to that of ADH without RS and therefore should be managed similarly. RS associated with LN is less frequently associated with malignant outcome. Most lesions exhibiting some degree of atypia showed similar upgrade rate to invasive carcinoma. Management of RS should be based on the concurrent atypical lesion.