BACKGROUND: Radial scars (RS) and complex sclerosing lesions (CSL) are benign breast lesions often detected incidentally on imaging. Although historically managed with surgical excision, emerging evidence suggests that conservative management may be appropriate in selected patients. This study evaluated rates of upgrade and progression of RS and CSL and examined factors associated with surgical management and these outcomes. METHODS: A retrospective cohort study was conducted at two academic centers affiliated with McGill University. Adult patients diagnosed with RS or CSL on image-guided core needle biopsy between 2010 and 2024 were included. Upgrade or progression was defined as a subsequent diagnosis of invasive carcinoma, carcinoma in situ (including ductal carcinoma in situ DCIS or pleomorphic lobular carcinoma in situ), or high-risk lesion (HRL), including atypical ductal hyperplasia (ADH). Descriptive statistics and univariate analysis were used to evaluate associations between clinicopathologic factors and outcomes. RESULTS: Among 185 patients, 49 (26.5%) underwent surgical excision and 136 (73.5%) were managed non-operatively. Surgical pathology revealed 1 invasive carcinoma (2.0%), 5 DCIS (10.2%), and 4 HRL (8.2%). In the non-surgical group, 3 patients (2.2%) subsequently developed invasive carcinoma; no DCIS or HRL developed over a median follow-up of 37 months. Presence of a palpable mass was the only factor that predicted surgical management (OR 2.65, 95% CI 1.06-6.60, p = 0.036); no other clinicopathologic or imaging features were associated with upgrade or progression. CONCLUSIONS: Although the surgical cohort demonstrated a higher-than-expected upgrade rate, most upgrades consisted of DCIS or HRL, and progression among non-surgically managed patients was rare after more than 3 years of follow-up. These findings suggest that RS and CSL are rarely associated with clinically significant disease, supporting surveillance as an appropriate management strategy in contemporary practice.
Zakem et al. (Mon,) studied this question.