Flat epithelial atypia and risk of breast cancer: A Mayo cohort study

Abstract

Background Based on its cytologic features, and its co-occurrence with atypical hyperplasia and breast cancer, flat epithelial atypia (FEA) has been proposed as a precursor lesion on the pathway to breast cancer development. It is often referred to as an “atypical” or high-risk lesion. However, the long term risk of breast cancer in women with FEA is undefined. Methods Biopsies with FEA were identified in excisional breast biopsies in the Mayo Clinic Benign Breast Disease (BBD) Cohort, which includes 11,591 women who had benign biopsies at Mayo-Rochester 1967–2001. Breast cancer risk of FEA, non-proliferative, proliferative and atypical hyperplasia (AH) subsets was assessed using standardized incidence ratios (SIRs), relative to the Iowa Surveillance, Epidemiology, and End Results registry. Results FEA was identified in 282 women (2.4%); 130 had associated AH (46%) and 152 (54%) were classified as proliferative disease without atypia (PDWA). With median follow-up of 16.8 years, the SIR for breast cancer in AH + FEA was 4.74 (95% CI: 3.17–6.81) versus 4.23 (3.44–5.13) for AH without FEA (p=0.59). The SIR for PDWA + FEA was 2.04 (95% CI: 1.23–3.19) versus 1.90 (1.72–2.09) for PDWA without FEA (p=0.76). Conclusions FEA is an uncommon finding in women with BBD. FEA does not convey independent risk of breast cancer beyond that of the associated PDWA or AH.

Gene Methylation and Cytological Atypia in Random Fine-Needle Aspirates for Assessment of Breast Cancer Risk

“…However, with the exception of atypical hyperplasia and very dense breasts, the risk associated with each of these factors is modest. Even the strongest risk factors of atypia (47, 48) and dense breasts (49) identify many women who will never develop breast cancer, leading to a search for molecular markers that would increase both the sensitivity and the specificity of present risk assessment methods.…”

Flat epithelial atypia on core needle biopsy does not always mandate excisional biopsy

“…For the 31 patients in their study with FEA plus AH, the upgrade rate to DCIS or invasive cancer was 19.4%, and they recommended surgical excision. Lastly, Said et al examined the Mayo Clinic Benign Breast Disease Cohort from 1967 to 2001 and identified 282 patients with FEA . Of the 152 (54%) patients with pure FEA, the standardized incidence ratios (SIRs) for development of subsequent breast cancer were 2.04 (95% CI: 1.23‐3.19).…”

Surgical implications and variability in the use of the flat epithelial atypia diagnosis on breast biopsy specimens

“…The counter argument is that the associated coexisting disease is relatively indolent and could be managed with surveillance. 8–10,16,17,19 In addition, the intrinsic biologic risk for future breast cancer is considerably lower for FEA than for ADH. 38 …”