What is the significance of flat epithelial atypia and what are the management implications?

Abstract

The presence of FEA on core biopsy warrants further tissue sampling to ensure concomitant malignancy is not missed. Sampling with VAB provides sufficient tissue for histopathological evaluation, reducing the need for surgical biopsy. It is important that the utilisation of VAB is incorporated into a safe patient management pathway with careful multidisciplinary team discussion to ensure radiological-pathological concordance.

Does Isolated Flat Epithelial Atypia on Vacuum-assisted Breast Core Biopsy Require Surgical Excision?

“…Recently there have been multiple studies looking at FEA, some recommend excision some do not recommend excision , and some recommend a multi‐disciplinary review . However, the low incidence of upgrade of isolated FEA to malignancy , was a common element of all these studies, including our study.…”

The low nuclear grade breast neoplasia family

“…The risk of subsequent malignancy (positive predictive value; PPV) following a diagnosis of CCL with atypia on NCB varies from 15% to 18% in FEA which increases upto 20%e37% in CCL with ADH. 21,23,28 The PPV for LN is 15e40% and this rate increases to 50% in pure ADH and upto 60% in ADH associated with LN. Although the proportion of BC following NCB diagnosis of pure atypia is low (w2% of all BC), diagnosis of these lesions, which comprises w5% of all NCB diagnoses, carries important management implications.…”

“…Surgical excision is recommended as a second line of intervention in cases turn out to be malignant on VAB. 21 If the diagnostic excision specimen showed pure atypia with no evidence of DCIS or invasion, our policy in Nottingham is to discharge the patient to the National Health Service Breast Screening Programme (NHSBSP) if over 50 years or mammographic follow-up every year for younger women until they reach 50 years then discharge to NHSBSP. No clinical follow-up is offered.…”

“…22,27 Malignant tumours in excision specimens following the diagnosis of atypia on NCB include insitu (w70%) and less frequently invasive carcinomas (w30%) and these often show favourable histological and clinical features and belong to the LGBNF. 21,23 Diagnosis of atypia on NCB should trigger discussion at a multidisciplinary team meeting (MDT) and based on the findings a decision can be made whether to precede to excisional diagnostic biopsy or uncommonly vacuum assisted biopsy (VAB) or to offer follow-up.…”

“…CCL was the most frequent lesion seen with all types of low-grade invasive BC but it was more frequent with tubular carcinoma (TC) and invasive cribriform carcinoma (ICC) (92%) and less frequent in invasive lobular carcinoma (ILC) (60%). 2,3,20,21 ADH and low-grade DCIS: low-grade DCIS is characterized by clonal intraductal proliferation of evenly spaced, usually small monomorphic cells with uniform-sized hyperchromatic nuclei and inconspicuous nucleoli. Cells are polarized and generally arranged in cribriform and micropapillary patterns.…”