Flat epithelial atypia on core needle biopsy: which is the right management?

Are Columnar Cell Lesions the Earliest Non-Obligate Precursor in the Low-Grade Breast Neoplasia Pathway?

Columnar cell lesions (CCLs) of the breast comprise a spectrum of morphologic alterations of the terminal duct lobular unit involving variably dilated and enlarged acini lined by columnar epithelial cells. The World Health Organization currently classifies CCLs without atypia as columnar cell change (CCC) and columnar cell hyperplasia (CCH), whereas flat epithelial atypia (FEA) is a unifying term encompassing both CCC and CCH with cytologic atypia. CCLs have been increasingly recognized in stereotactic core needle biopsies (CNBs) performed for the assessment of calcifications. CCLs are believed to represent the earliest non-obligate precursor of low-grade invasive breast carcinomas as they share molecular alterations and often coexist with entities in the low-grade breast neoplasia pathway. Despite this association, however, the risk of progression of CCLs to invasive breast carcinoma appears low and may not exceed that of concurrent proliferative lesions. As the reported upgrade rates of pure CCL/FEA when identified as the most advanced high-risk lesion on CNB vary widely, the management of FEA diagnosed on CNB remains controversial. This review will include a historical overview of CCLs and will examine histologic diagnostic criteria, molecular alterations, prognosis and issues related to upgrade rates and clinical management.

Upgrade rate of percutaneously diagnosed pure flat epithelial atypia: systematic review and meta-analysis of 1,924 lesions

CONTEXT

Management remains controversial due to the risk of upgrade for malignancy from flat epithelial atypia (FEA). Data about the frequency and malignancy upgrade rates are scant. Namely, observational follow-up is advised by many studies in cases of pure FEA on core biopsy and in the absence of an additional surgical excision. For cases of pure FEA, the American College of Surgeons no longer recommends surgical excision but rather recommends observation with clinical and imaging follow-up.

OBJECTIVES

The aim of this study is to perform a systematic review and meta-analysis to calculate the pooled upgrade of pure FEA following core needle biopsies.

METHODS

A search of MEDLINE and Embase databases were conducted in December 2020. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. A fixed- or random-effects model was utilized. Heterogeneity among studies was estimated by utilizing the I2 statistic and considered high if the I2 was greater than 50%. The random-effects model with the DerSimonian and Laird method was utilized to calculate the pooled upgrade rate and its 95% confidence interval.

RESULTS

A total of 1924 pure FEA were analyzed among 59 included studies. The overall pooled upgrade rate to malignancy was 8.8%. The pooled upgrade rate for mammography only was 8.9%. The pooled upgrade rate for ultrasound was 14%. The pooled upgrade rate for mammography and ultrasound combined was 8.8%. The pooled upgrade rate for MRI-only cases was 27.3%.

CONCLUSIONS

Although the guidelines for the management of pure FEA are variable, our data support that pure FEA diagnosed at core needle biopsy should undergo surgical excision since the upgrade rate >2%.

The effect of delay of excisional biopsy on upstage rate for atypical ductal hyperplasia, flat epithelial atypia, intraductal papilloma, and radial scar

PURPOSE

When Core Needle Biopsy (CNB) demonstrates Atypical Ductal Hyperplasia (ADH), Flat Epithelial Atypia (FEA), Intraductal Papilloma (IDP), or Radial Scar/Complex Sclerosing Lesion (RS), excisional biopsy (EB) is often performed to rule out underlying malignancy with upstage rates (UR) ranging between 1 and 20%. The COVID-19 pandemic led to delayed EB for many patients. We sought to evaluate whether this delay was associated with higher UR.

METHODS

We performed a retrospective analysis of women who underwent CNB and then EB for ADH, FEA, IDP, or RS between 2017 and 2021 using an IRB-approved repository. UR was evaluated by days between CNB and EB.

RESULTS

473 patients met inclusion. 55 were upstaged to cancer (11.6%). 178 patients had pure ADH on CNB and 37 were upstaged (20.8%). 50 patients had pure FEA and 3 were upstaged (6%). 132 had pure IDP and 7 were upstaged (5.3%). 98 had pure RS and 1 was upstaged (1%). 7/15 (46.7%) had a combination of diagnoses or diagnosis with palpable mass and were upstaged. Days between CNB and EB were < 60 for 275 patients (58.1%), 60-90 for 108 (22.8%), 91-120 for 43 (9.1%), and > 120 for 47 (9.9%). There was no significant difference in UR (10.9% for < 60, 14.8% for 60-90, 7% for 90-120, and 12.8% for > 120, p = 0.54). UR for ADH was clinically increased after 60 days (27.8 vs. 17.5%), but this did not reach statistical significance (p = 0.1).

CONCLUSION

Surgical delay was not associated with an increased UR.

Visualization positioning-guided biopsy of suspicious breast microcalcifications: a retrospective cohort study

Background

At present, most histological evaluations of microcalcifications without a mass are performed using X-ray guided hook wire localization or vacuum-assisted stereotactic biopsy (VASB), but there are still several limitations to these techniques. Therefore, we designed a visualization positioning technique based on three directions of mammography to accurately locate suspected microcalcifications to guide the biopsy.

Methods

We retrospectively analyzed consecutive patients with suspicious microcalcifications who underwent visualization positioning-guided biopsy (VPB) from June 1, 2016, to June 1, 2021. The visualization positioning technique was performed using an electronic ruler to measure the vertical distance from the microcalcification core to the vertical lines on mammography.

Results

A total of 133 patients (median age 46 years; range, 22–87 years) who underwent VPB were included in our study. Among the 133 cases of microcalcifications based on pathological results, 104 were benign, 14 were high risk, and 15 were malignant. In 124 (93.2%) patients, microcalcification was confirmed during the first round of VPB specimen analysis. Only 6 (4.5%) and 3 (2.3%) patients underwent second and third extended resections, respectively, as the resected specimens did not contain microcalcifications. Four patients (3.0%) with malignant biopsy results underwent a subsequent operation. Two patients with DCIS underwent mastectomy and sentinel lymph node biopsy because of diffuse calcification. One patient had no residual cancer, and the other was upgraded to invasive ductal carcinoma (IDC). Two patients with IDC underwent breast-conserving surgery and mastectomy with sentinel lymph node biopsy.

Conclusions

VPB can be used to evaluate breast microcalcifications when a mass is not present, making it an effective diagnostic technique.

Upgrade Rate of Pure Flat Epithelial Atypia Diagnosed at Core Needle Biopsy: A Systematic Review and Meta-Analysis

Purpose

To perform a systematic review and meta-analysis to calculate the pooled upgrade rate of pure flat epithelial atypia (FEA) diagnosed at core needle biopsy (CNB).

Materials and Methods

A PubMed and Embase database search was performed in December 2019. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Study quality and publication bias were assessed. The upgrade rate of pure FEA to cancer, invasive carcinoma, and ductal carcinoma in situ (DCIS), as well as the co-occurrence rate of atypical ductal hyperplasia (ADH), with 95% CIs were calculated. A random effect model was used to integrate the proportions and their corresponding 95% CI. Study heterogeneity was calculated using τ2 and I 2 .

Results

A total of 2482 cases of pure FEA across 42 studies (mean age range, 46-59 years) met inclusion criteria to be analyzed. Significant study heterogeneity was identified (τ2 = 0.001, I 2 = 67%). The pooled upgrade rates reported for pure FEA were 5% (95% CI: 3%, 6%) for breast cancer, 1% (95% CI: 0%, 2%) for invasive carcinoma, and 2% (95% CI: 1%, 3%) for DCIS. When more than 90% of calcifications were removed at CNB, the pooled upgrade rate was 0% (95% CI: 0%, 2%). The pooled co-occurrence rate of ADH at surgical excision was 17% (95% CI: 12%, 21%). Study quality was medium to high with a risk of publication bias (P < .01).

Conclusion

Pure FEA diagnosed at CNB should be surgically excised due to the pooled upgrade rate of 5% for breast cancer. If more than 90% of the targeted calcifications are removed by CNB for pure FEA, close imaging follow-up is recommended.Keywords: Biopsy/Needle Aspiration, Breast, MammographySupplemental material is available for this article.© RSNA, 2021.

Positive predictive value for malignancy of uncertain malignant potential (B3) breast lesions diagnosed on vacuum-assisted biopsy (VAB): is surgical excision still recommended?

PURPOSE

Breast lesions classified as of "uncertain malignant potential" represent a heterogeneous group of abnormalities with an increased risk of associated malignancy. Clinical management of B3 lesions diagnosed on vacuum-assisted breast biopsy (VABB) is still challenging: surgical excision is no longer the only available treatment and VABB may be sufficient for therapeutic excision. The aim of the present study is to evaluate the positive predictive value (PPV) for malignancy in B3 lesions that underwent surgical excision, identifying possible upgrading predictive factors and characterizing the malignant lesions eventually diagnosed. These results are compared with a subset of patients with B3 lesions who underwent follow-up.

METHODS

A total of 1250 VABBs were performed between January 2006 and December 2017 at our center. In total, 150 B3 cases were diagnosed and 68 of them underwent surgical excision. VABB findings were correlated with excision histology. A PPV for malignancy for each B3 subtype was derived.

RESULTS

The overall PPV rate was 28%, with the highest upgrade rate for atypical ductal hyperplasia (41%), followed by classical lobular neoplasia (29%) and flat epithelial atypia (11%). Only two cases of carcinoma were detected in the follow-up cohort, both associated with atypical ductal hyperplasia at VABB.

CONCLUSION

Open surgery is recommended in case of atypical ductal hyperplasia while, for other B3 lesions, excision with VABB only may be an acceptable alternative if radio-pathological correlation is assessed, if all microcalcifications have been removed by VABB, and if the lesion lacks high-risk cytological features.

KEY POINTS

• Surgical treatment is strongly recommended in case of ADH, while the upgrade rate in case of pure FEA, especially following complete microcalcification removal by VABB, may be sufficiently low to advice surveillance as a management strategy. • The use of 11-G- or 8-G-needle VABB, resulting in possible complete diagnostic excision of the lesion, can be an acceptable alternative in case of RS, considering open surgery only for selected high-risk patients. • LN management is more controversial: surgical excision may be recommended following classical LN diagnosis on breast biopsy if an additional B3 lesion is concurrently detected while in the presence of isolated LN with adequate radiological-pathological correlation follow-up alone could be an acceptable option.

Lesions of uncertain malignant potential of the breast (B3) on vacuum-assisted biopsy for microcalcifications: Predictors of malignancy

PURPOSE

To investigate clinical, radiologic and pathologic features of B3 lesions diagnosed on VABB targeting microcalcifications, for identifying predictors of malignancy.

METHOD

This retrospective multi-centre study included consecutive VABBs performed over a 10-year period on suspicious microcalcifications not associated with other radiological signs diagnosed as B3 on histology from VABB, with outcomes ascertained by surgical excision. Clinical, demographic, radiological and histological (B3 subcategory) data were collected. For statistical analysis (univariate and binary logistic regression), the primary outcome variable was the upgrade rate to malignancy after surgery. Predictors of upgrade to malignancy were identified from clinical, demographic, radiological and pathological variables (including B3 subcategory).

RESULTS

Amongst 447 VABBs, there were 57(12.7 %) upgrades to malignancy at surgical histology (36 DCIS and 21 invasive cancer). At univariate analysis, variables significantly associated with increased risk of upgrade to malignancy were age>55 years (p = 0.01), lesion size>10 mm (p < 0.0001), BI-RADS 4b-c and 5 (p = 0.0001), and fine pleomorphic morphology (p = 0.002) of microcalcifications. Binary logistic regression confirmed as significant independent risk factors age, lesion size and BI-RADS category (p = 0.02, 0.02 and 0.0006 respectively). Amongst subcategories of B3 lesions, lobular neoplasia was significantly(p = 0.04) associated with upgrade, confirmed as an independent risk factor [p = 0.03, OR = 2.3(1.1-4.7)]. Flat epithelial atypia was significantly(p = 0.004) associated with reduced odds of upgrade, but binary logistic regression showed only borderline association [p = 0.052, OR = 0.4(0.2-1.01)].

CONCLUSIONS

Across B3 lesions diagnosed on histology from VABB of suspicious microcalcifications, older age, size>10 mm, BI-RADS category≥ 4b on imaging, and lobular neoplasia were risk factors for upgrade to malignancy. This information can be used to discuss patients' tailored management options.

Impact of Non-Calcified Specimen Pathology on the Underestimation of Malignancy for the Incomplete Retrieval of Suspicious Calcifications Diagnosed as Flat Epithelial Atypia or Atypical Ductal Hyperplasia by Stereotactic Vacuum-Assisted Breast Biopsy

Objective

Stereotactic vacuum-assisted breast biopsy (VABB) is considered a reliable alternative to surgical biopsy for suspicious calcifications. In most cases, the management of flat epithelial atypia (FEA) and atypical ductal hyperplasia (ADH) after VABB with residual calcifications requires surgical excision. This study aimed to evaluate the impact of pathology of non-calcified specimens on the underestimation of malignancy.

Materials and Methods

We retrospectively reviewed 1147 consecutive cases of stereotactic VABB of suspicious calcifications without mass from January 2010 to December 2016 and identified 46 (4.0%) FEA and 52 (4.5%) ADH cases that were surgically excised for the retrieval of residual calcifications. Mammographic features and pathology of the calcified and non-calcified specimens were reviewed.

Results

Seventeen specimens (17.3%) were upgraded to malignancy. Mammographic features associated with the underestimation of malignancy were calcification extent (> 34.5 mm: odds ratio = 6.059, p = 0.026). According to the pathology of calcified versus non-calcified specimens, four risk groups were identified: Group A (ADH vs. high-risk lesions), Group B (ADH vs. non-high-risk lesions), Group C (FEA vs. high-risk lesions), and Group D (FEA vs. non-high-risk lesions). The lowest underestimation rate was observed in Group D (Group A vs. Group B vs. Group C vs. Group D: 35.0% vs. 20.0% vs. 15.0% vs. 3.6%, p = 0.041, respectively).

Conclusion

Considering that the calcification extent and pathology of non-calcified specimens may be beneficial in determining the likelihood of malignancy underestimation, excision after FEA or ADH diagnosis by VABB is required, except for the diagnoses of FEA coexisting without atypia lesions in non-calcified specimens.

Flat Epithelial Atypia in Breast Core Needle Biopsies With Radiologic-Pathologic Concordance: Is Excision Necessary?

Flat epithelial atypia (FEA) is an alteration of terminal duct lobular units by a proliferation of ductal epithelium with low-grade atypia. No consensus exists on whether the diagnosis of FEA in core needle biopsy (CNB) requires excision (EXC). We retrospectively identified all in-house CNBs obtained between January 2012 and July 2018 with FEA. We reviewed all CNB slides and assessed radiologic-pathologic concordance. An upgrade was defined as invasive carcinoma (IC) and/or ductal carcinoma in situ in the EXC. The EXC slides of all upgraded cases were rereviewed. Out of ∼15,700 consecutive CNBs in the study period, 106 CNBs from 106 patients yielded FEA alone or with classic lobular neoplasia (LN). We excluded 52 CNBs (40 patients with prior/concurrent carcinoma and 12 without EXC). After rereview, we reclassified 14 cases (2 marked nuclear atypia, 10 focal atypical ductal hyperplasia, 2 benign). The final FEA study cohort consisted of 40 CNBs from 40 women. The CNB targeted mammographic calcifications in 36 (90%) cases, magnetic resonance imaging nonmass enhancement in 3 (8%), and 1 (2%) sonographic mass. All CNBs were deemed radiologic-pathologic concordant. FEA was present alone in 34 CNBs and with LN in 6. EXC yielded 2 low-grade IC, each spanning <2 mm, identified in tissue sections without biopsy site changes. The remaining 38 cases had no upgrade. Classic LN did not affect the upgrade. The upgrade rate of FEA was 5%; both minute, low-grade "incidental" IC. We conclude that nonsurgical management may be considered in patients without prior/concurrent carcinoma and radiologic-pathologic concordant CNB diagnosis of FEA.

Flat epithelial atypia in directional vacuum-assisted biopsy of breast microcalcifications: surgical excision may not be necessary

The aim of this study was to analyze the clinicopathological features of patients with flat epithelial atypia, diagnosed in directional vacuum-assisted biopsy targeting microcalcifications, to identify upgrade rate to in situ ductal or invasive breast carcinoma, and determine factors predicting carcinoma in the subsequent excision. We retrospectively evaluated the histological, clinical, and mammographic features of 69 cases from 65 women, with directional vacuum-assisted biopsy-diagnosed flat epithelial atypia with or without atypical ductal hyperplasia or atypical lobular hyperplasia, which underwent subsequent surgical excision. The extent and percentage of microcalcifications sampled by directional vacuum-assisted biopsy were evaluated by mammography. All biopsy and surgical excision slides were reviewed. The age of the women ranged from 40 to 85 years (mean 57 years). All patients presented with mammographically detected microcalcifications only, except in one case that had associated architectural distortion. Extent of calcifications ranged from <1 cm (n = 47), 1-3 cm (n = 15) to > 3 cm (n = 6), and no measurement (n = 1). A mean of 11 cores (range 6-25) was obtained from each lesion. Post-biopsy mammogram revealed >90% removal of calcifications in 81% of cases. Pure flat epithelial atypia represented nearly two-thirds of directional vacuum-assisted biopsy specimens (n = 43, 62%), while flat epithelial atypia coexisted with atypical ductal hyperplasia (18 cases, 26%), or atypical lobular hyperplasia (8 cases, 12%). Upon excision, none of the cases were upgraded to in situ ductal or invasive breast cancer. In one case, however, an incidental, tubular carcinoma (4 mm) was found away from biopsy site. Excluding this case, the upgrade rate was 0%. Our study adds to the growing evidence that diagnosis of flat epithelial atypia on directional vacuum-assisted biopsy for microcalcifications as the only imaging finding is not associated with a significant upgrade to carcinoma on excision, and therefore, excision may not be necessary. Additionally, excision may not be necessary for flat epithelial atypia with atypical ductal hyperplasia limited to ≤2 terminal duct-lobular units, if at least 90% of calcifications have been removed on biopsy.

Pathologic Upgrade Rates of High-Risk Breast Lesions on Digital Two-Dimensional vs Tomosynthesis Mammography

BACKGROUND

Our aim was to compare the pathologic upgrade rates of high-risk breast lesions (HRLs) on digital two-dimensional mammography (DM) vs digital breast tomosynthesis (DBT).

STUDY DESIGN

The study cohort was composed of patients with HRLs diagnosed by image-guided core needle biopsy from December 2007 to February 2011 (DM group, before DBT integration) and from January 2013 to March 2016 (DBT group, after complete DBT integration). Medical records were reviewed for surgical outcomes and follow-up imaging.

RESULTS

Eight hundred and ninety-three patients with 900 biopsy-proven HRLs underwent surgical excision (97.0% [873 of 900]) or had at least 2 years of imaging follow-up (3.0% [27 of 900]). The most common HRL was atypical ductal hyperplasia in the DM and DBT groups (37.4% [337 of 900]). The overall upgrade rate of HRLs to malignancy was 11.3% (102 of 900). There were no statistically significant differences in overall upgrades rates of HRLs on DM vs DBT (11.4% [54 of 475] vs 11.3% [48 of 425]; p = 0.97) or in upgrade rates of HRL subtypes. However, HRLs that upgraded on DBT were more likely to be invasive rather than in situ carcinoma compared with HRLs that upgraded on DM (39.6% [19 of 48] vs 20.4% [11 of 54]; p = 0.03). Overall, the most common HRL to upgrade was atypical ductal hyperplasia (18.4% [62 of 337]). The least common HRLs to upgrade in the DBT group were biphasic neoplasms (0% [0 of 22]), flat epithelial atypia (1.6% [1 of 62]), and papillomas without atypia (4.5% [2 of 44]).

CONCLUSIONS

There is no difference in the upgrade rates of HRLs on DM vs DBT, but the proportion of HRL upgrades that are invasive rather than in situ carcinoma is higher with DBT.

Flat epithelial atypia: conservative management of patients without residual microcalcifications post-vacuum-assisted breast biopsy

OBJECTIVE

To determine the malignancy rate (defined in this study as stability or absence of malignancy developed on close imaging follow-up post-biopsy) of conservative management in patients with a vacuum-assisted breast biopsy (VAB) diagnosis of flat epithelial atypia (FEA), performed on single group of microcalcifications, completely removed during procedure.

METHODS

This is a retrospective, monocentric, observational study, approved by IRB. Inclusion criteria were: VAB performed on a single group of microcalcifications; the absence of residual calcifications post-VAB; diagnosis of isolated FEA as the most advanced proliferative lesion; radiological follow-up at least of 12 months. The personal history of breast cancer or other high-risk lesions was an exclusion criteria. The patients enrolled were conservatively managed, without surgical excision, through close follow-up: the first two mammographies performed with an interval of 6 months after biopsy, followed by annual mammographic and clinical checks.

RESULTS

48 consecutive patients were enrolled in the study, all females, with age range of 39-76 years (mean 53,3 years) and radiological follow-up range of 13-75 months (mean 41.5 months). All the lesions were classified as BI-RADS 4b. The diameter range of the group of calcifications was 3-10 mm (mean 5, 6 mm). In each patient, 7 to 15 samples (mean 11) were obtained. Among all the patients, there was only one case (2%) of new microcalcifications, developed in the same breast, 26 months after and 8 mm from the site of previous VAB, and interpreted as ADH at surgical excision. All the checks of the other patients were negative.

CONCLUSION

Even with a limited follow-up, we found a malignancy rate lower than 2%, through a defined population. Further studies with bigger number of patients and extended follow-up are needed to reinforce this hypothesis. Advances in knowledge: Surgical excision may not be necessary in patients with VAB diagnosis of isolated FEA, without residual microcalcifications post-procedure and considered concordant with the mammographic presentation, considering the low rate of malignancy at subsequent follow-ups.

Flat Epithelial Atypia on Core Biopsy and Upgrade to Cancer: a Systematic Review and Meta-Analysis

BACKGROUND

No consensus exists on whether flat epithelial atypia (FEA) diagnosed percutaneously should be surgically excised. A systematic review and meta-analysis of the frequency of upgrade to cancer or an atypical ductal hyperplasia (ADH) at surgical excision of FEA was performed.

METHODS

Embase, MEDLINE, Scopus, and Web of Science databases from January 2003 to November 2015 were searched. The inclusion criteria required a manuscript in English with original data on FEA diagnosed percutaneously, data including the presence or absence of other concurrent high-risk lesions, and data including outcome of cancer at surgical excision. Studies were assessed for quality, and two reviewers extracted data. Random-effects meta-analysis was used to pool estimates. The impact of study-level characteristics was assessed by stratified meta-analysis and meta-regression.

RESULTS

The inclusion criteria was met by 32 studies. A total of 1966 core needle biopsies showed pure FEA, and 1517 (77%) showed surgical excision. The proportions of patients with upgrade to cancer varied from 0 to 42%, with an overall pooled estimate of 11.1%. Heterogeneity was observed, with the greatest impact based on whether a study included cases of FEA diagnosed before 2003. With restriction of the investigation to 16 higher-quality studies, the cancer upgrade pooled estimate was 7.5% (95% confidence interval [CI], 5.4-10.4%), and the rate of invasive cancer was 3% (95% CI 1.9-4.5%). For upgrade to ADH, data from 22 studies including 937 patients were analyzed. The proportion of patients upgraded to ADH ranged from 0 to 60%, with a pooled estimate of 17.9% overall and 18.6% among high-quality studies.

CONCLUSIONS

With patient management change potential for approximately 25% of patients, this analysis supports a general recommendation for surgical excision of FEA diagnosed by core biopsy.

Upgrade rates of high-risk breast lesions diagnosed on core needle biopsy: a single-institution experience and literature review

Optimal management of high-risk breast lesions detected by mammogram yielding atypical ductal hyperplasia, flat epithelial atypia, atypical lobular hyperplasia, lobular carcinoma in situ, and radial scar without atypia on core needle biopsy is controversial. This is a single-institution retrospective review of 5750 core needle biopsy cases seen over 14.5 years, including 249 (4.3%), 72 (1.3%), 50 (0.9%), 37 (0.6%), and 54 (0.9%) cases of atypical ductal hyperplasia, flat epithelial atypia, atypical lobular hyperplasia, lobular carcinoma in situ, and radial scar without atypia, respectively. Patient age, radiologic characteristics, needle gauge, and excision diagnoses were recorded. Of 462 high-risk cases analyzed, 333 (72%) underwent excision. Upgrade rate to ductal carcinoma in situ, pleomorphic carcinoma in situ, or invasive mammary carcinoma was 18% for atypical ductal hyperplasia, 11% for flat epithelial atypia, 9% for atypical lobular hyperplasia, 28% for lobular carcinoma in situ, and 16% for radial scar. Carcinoma diagnosed on excision was more likely to be in situ than invasive, and if invasive, more likely to be low grade than high grade. Overall, cases that were benign (vs high risk or carcinoma) on excision were less likely to have residual calcifications after biopsy (17% vs 27%, P=0.013), and more likely to have a smaller mass size (<1 cm) (82% vs 50%, P=0.001). On subgroup analysis, atypical ductal hyperplasia cases that were benign (vs high risk or carcinoma) on excision were more likely to have smaller mass size (<1 cm) (P=0.025). Lobular neoplasia diagnosed incidentally (vs targeted) on core needle biopsy was less likely to upgrade on excision (5% vs 39%, P=0.002). A comprehensive literature review was performed, identifying 116 studies reporting high-risk lesion upgrade rates, and our upgrade rates were similar to those of more recent larger studies. Careful radiological-pathological correlation is needed to identify high-risk lesion subgroups that may not need excision.

First International Consensus Conference on lesions of uncertain malignant potential in the breast (B3 lesions)

The purpose of this study is to obtain a consensus for the therapy of B3 lesions. The first International Consensus Conference on lesions of uncertain malignant potential in the breast (B3 lesions) including atypical ductal hyperplasia (ADH), flat epithelial atypia (FEA), classical lobular neoplasia (LN), papillary lesions (PL), benign phyllodes tumors (PT), and radial scars (RS) took place in January 2016 in Zurich, Switzerland organized by the International Breast Ultrasound School and the Swiss Minimally Invasive Breast Biopsy group-a subgroup of the Swiss Society of Senology. Consensus recommendations for the management and follow-up surveillance of these B3 lesions were developed and areas of research priorities were identified. The consensus recommendation for FEA, LN, PL, and RS diagnosed on core needle biopsy or vacuum-assisted biopsy (VAB) is to therapeutically excise the lesion seen on imaging by VAB and no longer by open surgery, with follow-up surveillance imaging for 5 years. The consensus recommendation for ADH and PT is, with some exceptions, therapeutic first-line open surgical excision. Minimally invasive management of selected B3 lesions with therapeutic VAB is acceptable as an alternative to first-line surgical excision.

Atypical epithelial hyperplasia of the breast: state of the art

INTRODUCTION

Atypical epithelial hyperplasia (AEH) of the breast is considered benign histological lesions with breast cancer risk. This review focuses on clinical signification and management of AEH that remains controversial.

AREAS COVERED

A review of published studies was performed using medline database. In this review, we fully describe the current evidence available. In particular, we describe 1) data from immunohistochemistry and molecular studies that suggest AEH is a precursor of breast cancer; 2) epidemiological studies demonstrate low rate of breast cancer in women with AEH; 3) surgical excision is necessary after diagnosis of AEH, such as lobular carcinoma in situ or atypical ductal hyperplasia, on core needle biopsy; 4) although current recommendations are evolving to fewer (if not no) excisions for flat epithelial with atypia and classic lobular neoplasia found on percutaneous biopsy (without radiologic indications for excision). Expert commentary: HEA management steel need prospective evidences, but recent retrospective data give some clue for less invasive management for some of HEA.

Diagnosis of Columnar Cell Lesions and Atypical Ductal Hyperplasia by Ultrasound-Guided Core Biopsy: Findings Associated with Underestimation of Breast Carcinoma

The aim of the study described here was to determine underestimation rates and identify radiologic predictors of underestimation for columnar cell lesions (CCLs) and atypical ductal hyperplasia (ADH) detected by ultrasound-guided core needle biopsy. A total of 103 CCLs and ADH lesions in 100 patients diagnosed by ultrasound-guided core needle biopsy were evaluated. Breast sonographic and mammographic findings were reviewed, and underestimation rates were determined by surgical excision, percutaneous vacuum-assisted excision or 2-y imaging follow-up. All underestimated lesions were ductal carcinoma in situ, and the underestimation rates of flat epithelial atypia (FEA), FEA + ADH and ADH were 5.9% (1/17), 44.4% (4/9) and 27.3% (12/44), respectively. There was no underestimation of CCLs without atypia. The presence of calcifications on ultrasound was significantly associated with underestimation (p = 0.010). Therefore, except for CCLs without atypia, all other lesions may require excision, especially when calcification is present on ultrasound or when FEA + ADH is found.

Analysis of Clinical and Pathologic Factors of Pure, Flat Epithelial Atypia on Core Needle Biopsy to Aid in the Decision of Excision or Observation

BACKGROUND

The optimal treatment of flat epithelial atypia (FEA) found on breast core needle biopsy (CNB) is controversial. We performed a retrospective review of our institutional experience with FEA to determine if excisional biopsy may be deferred.

METHODS

Surgical records from 2009 to 2012 were reviewed for FEA diagnosis. After exclusion for concomitant lesions, CNBs of pure FEA were classified using a previously agreed upon descriptor of "focal" versus "prominent". Data was analyzed with the Fisher's Exact and Student-t test as appropriate.

RESULTS

Of 71 CNBs evaluated, pure FEA was identified on 27 CNBs. Final excisional biopsy was benign in 24 of 27 cases (88%) with associated ductal carcinoma in-situ (DCIS) in 3 of 27 cases (11%). Eighteen of 27 (67%) CNBs were classified as focal while 9 (33%) were described as prominent. Zero of the 18 focal patients had a malignancy compared to 3 of the 9 in the prominent group (0% vs 33%, p=0.02). Of the 27 pure FEA CNBs, 6 patients had a personal history of breast carcinoma, five DCIS and one invasive ductal carcinoma. No malignancies were found in the 21 patients without a personal history of breast carcinoma versus three in the patients with a positive history (0/21 v 3/6, p=0.007).

CONCLUSIONS

Our data suggests those women who have adequate sampling and sectioning of CNBs, with focal, pure FEA on pathology, and are without a personal history of breast cancer may undergo a period of imaging surveillance. Conversely, patients with a history of breast cancer or pure, prominent FEA on CNB disease should proceed to excisional biopsy.

[Benign proliferative breast disease with and without atypia]

In the last few years, diagnostics of high-risk breast lesions (atypical ductal hyperplasia [ADH], flat epithelial atypia [FEA], lobular neoplasia: atypical lobular hyperplasia [ALH], lobular carcinoma in situ [LCIS], radial scar [RS], usual ductal hyperplasia [UDH], adenosis, sclerosing adenosis [SA], papillary breast lesions, mucocele-like lesion [MLL]) have increased with the growing number of breast percutaneous biopsies. The management of these lesions is highly conditioned by the enlarged risk of breast cancer combined with either an increased probability of finding cancer after surgery, either a possible malignant transformation (in situ or invasive cancer), or an increased probability of developing cancer on the long range. An overview of the literature reports grade C recommendations concerning the management and follow-up of these lesions: in case of ADH, FEA, ALH, LCIS, RS, MLL with atypia, diagnosed on percutaneous biopsies: surgical excision is recommended; in case of a diagnostic based on vacuum-assisted core biopsy with complete disappearance of radiological signal for FEA or RS without atypia: surgical abstention is a valid alternative approved by multidisciplinary meeting. In case of ALH (incidental finding) associated with benign lesion responsible of radiological signal: abstention may be proposed; in case of UDH, adenosis, MLL without atypia, diagnosed on percutaneous biopsies: the concordance of radiology and histopathology findings must be ensured. No data is available to recommend surgery; in case of non-in sano resection for ADH, FEA, ALH, LCIS (except pleomorphic type), RS, MLL: surgery does not seem to be necessary; in case of previous ADH, ALH, LCIS: a specific follow-up is recommended in accordance with HAS's recommendations. In case of FEA and RS or MLL combined with atypia, little data are yet available to differ the management from others lesions with atypia; in case of UDH, usual sclerosing adenosis, RS without atypia, fibro cystic disease: no specific follow-up is recommended in agreement with HAS's recommendations.

Management of flat epithelial atypia on breast core biopsy may be individualized based on correlation with imaging studies

Flat epithelial atypia of the breast commonly co-exists with atypical ductal hyperplasia, lobular neoplasia, and indolent forms of invasive carcinomas such as tubular carcinoma. Most patients with pure flat epithelial atypia on core biopsy undergo surgical excision to evaluate for carcinoma in the adjacent breast tissue. Studies to date have reported varying upgrade rates with most recommending follow-up excision. These studies have often lacked detailed radiographic correlation, central review by breast pathologists and information regarding the biology of the carcinomas identified upon excision. In this study, we report the frequency of upgrade to invasive carcinoma or ductal carcinoma in situ in excision specimens following a diagnosis of pure flat epithelial atypia on core biopsy. Radiographic correlation is performed for each case and grade/receptor status of detected carcinomas is reported. Seventy-three (73) core biopsies containing pure flat epithelial atypia were identified from our files, meeting inclusion criteria for the study. In the subsequent excision biopsies, five (7%) cases contained invasive carcinoma or ductal carcinoma in situ and seventeen (23%) contained atypical ductal hyperplasia or lobular neoplasia. All of the ductal carcinoma in situ cases with estrogen receptor results were estrogen receptor positive and intermediate grade. The invasive tumors were small (pT1a) hormone receptor-positive, HER2-negative, low-grade invasive ductal or tubular carcinomas with negative sentinel lymph-node biopsies. No upgrades were identified in the 14 patients who had all of their calcifications removed by the stereotactic core biopsy. Our rate of upgrade to carcinoma, once cases with discordant imaging are excluded, is at the lower end of the range reported in the literature. Given the low upgrade rate and indolent nature of the carcinomas associated with flat epithelial atypia, case management may be individualized based on clinical and radiographic findings. Excision may not be necessary for patients without remaining calcifications following core biopsy.

Current management of lesions associated with an increased risk of breast cancer

High-risk breast lesions, which comprise benign lesions and in situ carcinomas (lobular carcinoma in situ and ductal carcinoma in situ), are clinically, morphologically, and biologically heterogeneous and are associated with an increased risk of invasive breast cancer development, albeit to varying degrees. Recognition and proactive management of such lesions can help to prevent progression to invasive disease, and might, therefore, reduce breast cancer incidence, morbidity, and mortality. However, this opportunity comes with the possibility of overdiagnosis and overtreatment, necessitating risk-based intervention. Notably, despite the progress in defining the molecular changes associated with carcinogenesis, alterations identifying the individuals with high-risk lesions that will progress to invasive carcinoma remain to be identified. Thus, until reproducible clinicopathological or molecular features predicting an individual's risk of breast cancer are found, management strategies must be defined by population-level risks as determined by models such as the Gail or IBIS models, as well as patient attitudes toward the risks and benefits of interventions. Herein, we review the contemporary approaches to diagnosis and management of high-risk breast lesions. Progress in this area will ultimately be dependent on the ability to individualize risk prediction through better definition of the key drivers in the carcinogenic process.

[Breast surgeon role in the management of high-risk breast lesions]

Diagnostics of high-risk breast lesions have increased these last years with the augmentation of breast percutaneous biopsies. They are lesions that confer an enlarged risk of breast cancer, either because of an increased probability of finding cancer after open surgery, a possible evolution toward in situ or invasive cancer, or because of an increased probability of developing breast cancer over the long term. Much progress has been made these last years in their histological diagnostic, classification and pathogenesis. Nevertheless, no consensus exists to date on the management of these "high-risk" lesions. In particular, surgical indications and follow-up modalities remain controversial for each histological type. In this review, the principal factors that could impact surgical decision and long-term follow-up are discussed with areas of controversy highlighted.

Positive predictive value for malignancy of pure flat epithelial atypia diagnosis by percutaneous needle biopsy of the breast: management of FEA in ultrasonography

BACKGROUND

Some reports suggest that the rate of definitive diagnosis of malignant tumors, namely, the final diagnosis being revised to a higher stage, in patients diagnosed as having flat epithelial atypia (FEA) by percutaneous needle biopsy of the breast (PNB) is as low as 0-3 %. However, other reports suggest that the rate is as high as 10 % or more, bringing confusion on this issue. We examined the positive predictive value for malignancy in the patients diagnosed as having pure FEA and the patients' radiolopathological characteristics observed in our hospital.

METHODS

Of the patients who underwent PNB in our facility, those who were diagnosed as having pure FEA were recruited as the subjects of this study.

RESULTS

Of the 4,197 consecutive patients who underwent PNB, 44 (1.0 %) were diagnosed as having pure FEA following a re-examination. Among 44 cases, 39 cases were selected as the subjects of this study. Among the 39 patients, six patients were diagnosed as having malignant lesions, two of whom had invasive carcinoma of no special type (papillotubular type), one had tubular carcinoma, one had ductal carcinoma in situ (DCIS) of high nuclear grade, one had DCIS of intermediate nuclear grade, and one had DCIS of low nuclear grade. The diameters of 6 malignant lesions were 10-30 mm at ultrasonography (US) examination. Five of the 39 patients had contralateral breast cancer.

CONCLUSION

The positive predictive value for malignancy of pure FEA was 15.7 %. The patients with pure FEA may make a follow up without an excisional biopsy when the lesion sizes less than 10 mm on US examination.

Flat epithelial atypia: comparison between 9-gauge and 11-gauge devices

BACKGROUND

This study aimed to establish if women with a diagnosis of flat epithelial atypia (FEA) without residual microcalcifications at stereotactic vacuum-assisted breast biopsy (VABB) could be managed with mammographic follow-up (FU) instead of surgery and to compare 9-gauge and 11-gauge devices.

PATIENTS AND METHODS

From October 2003 to January 2011, 2382 VABB procedures were performed (1373 with 11-gauge and 1009 with 9-gauge). We found 121 cases of pure FEA that were surgically treated: 57 with a 9-gauge device (group 1) and 64 with an 11-gauge device (group 2). The underestimation rate (UR) of malignancy for patients without and those with residual microcalcifications for each VABB device was calculated. Differences between groups were analyzed with the Fischer exact test.

RESULTS

The overall UR of FEA was 4% (2 of 57) with the 9-gauge device and 8% (5 of 64) with the 11-gauge device. With a 9-gauge device, the UR for patients without residual microcalcifications was 0% (0 of 46), and the UR for patients with residual microcalcifications was 18% (2 of 11). With an 11-gauge device, the UR for patients without residual microcalcifications was 0% (0 of 39), the UR for patients with residual microcalcifications at post-biopsy mammograms was 16% (5 of 25). With a 9-gauge device, 80% (46 of 57) of patients did not have residual microcalcifications after VABB. With an 11-gauge device, 60% (39 of 64) of patients had no residual microcalcifications after VABB. Differences between the 9-gauge and 11-gauge devices were statistically significant (P < .05).

CONCLUSION

Women with FEA without residual microcalcifications after VABB can be managed conservatively. Nine-gauge VABB is associated with a lower percentage of residual microcalcifications compared with an 11-gauge device, but it is safe to follow patients with FEA if all calcifications are removed with the core biopsy.

An unusual case of a large fibroepithelial stromal polyp presenting as a nipple mass

Background

Fibroepithelial stromal polyps (FESP) are benign lesions that typically occur in the genital area and are known to represent a diagnostic challenge for pathologists. Not only do they have a spectrum of morphological changes that ranges from bland morphology to rather atypical appearances, but they also share morphological features with a number of benign and malignant lesions.

This is a report of a rare presentation of a FESP of the breast.

Case presentation

We describe an unusual case of a large polypoid mass arising from the nipple and connected to it by a long pedicle in a female of 45. The lesion comprised spindle and stellate shaped cells with bizarre stromal giant cells. The morphological and immunohistochemical diagnostic features are provided together with a discussion of possible mimics.

Conclusion

FESPs may occur in the female breast. It is important to differentiate the lesion from other benign and malignant spindle cell lesions particularly metaplastic carcinoma.

Radiologic-pathologic correlation at breast MR imaging: what is the appropriate management for high-risk lesions?

Breast magnetic resonance (MR) imaging is increasingly performed for a variety of indications, most commonly with the goal of detecting breast cancer. Percutaneous biopsy (usually under MR guidance or ultrasound if there is a correlating finding) is commonly used to evaluate suspicious imaging findings detected on MR imaging with the goal of identifying malignancy. It is important to be familiar with the characteristics and management of high-risk lesions detected or biopsied under MR guidance. This review focuses on the appearance of a variety of breast lesions detected on MR imaging that require excision with focus on pathologic correlation.

Pure flat epithelial atypia: is there a place for routine surgery?

PURPOSE

To determine whether it is appropriate to routinely undertake surgery if flat epithelial atypia (FEA) or pure flat epithelial atypia (pFEA) is found on large-core biopsy.

PATIENTS AND METHODS

Between 2005 and 2010, 1678 large-core biopsy procedures were carried out, which led to 136 FEA sites being identified, 63 of which across 59 patients were pFEA (four patients had two sites of pFEA each). Forty-eight patients underwent further surgical excision, equating to 52 excised sites of pFEA.

RESULTS

Of the 52 operated sites, there were 20 benign lesions (38%), 26 borderline lesions (56%), and three ductal carcinomas in situ (6%). The rate of histologic underestimation was put at 3.8%. Of the three cases that were underestimated, one was discarded because the definitive histology was not representative of the site from which microcalcifications had initially been taken. The other two cases that were underestimated were found in patients with an increased individual risk of breast cancer.

CONCLUSION

In patients with no personal or first-degree family history of breast cancer, after complete or subtotal excision under radiology of the radiological lesion, and while excluding images fitting BI-RADS 5, annual monitoring may be offered as an alternative to surgical excision in view of the absence of underestimation found in our study.

Surgical management of high-risk breast lesions

High-risk lesions of the breast are lesions that confer an increased risk of breast cancer, either because of an increased probability of finding cancer associated with percutaneous biopsy findings or because of an increased probability of developing breast cancer over the long term. Atypical ductal hyperplasia found on percutaneous biopsy is generally excised, whereas lobular neoplasia lesions, including both atypical lobular hyperplasia and lobular carcinoma in situ, may be observed if radiologic and pathologic findings are concordant and there is no other high-risk lesion present.

Incidence of breast cancer in patients with pure flat epithelial atypia diagnosed at core-needle biopsy of the breast

PURPOSE

to determine the frequency of malignancy in subsequent breast excisions following core-needle biopsy (CNB) diagnosis of pure flat epithelial atypia (pFEA) and to evaluate the imaging features of the associated tumors.

MATERIALS AND METHODS

Retrospective review of 8,996 image-guided CNB (2002-2010) identified 115 cases of FEA not associated with other atypia. Patients with history of breast cancer or radiation therapy were excluded. One hundred four cases (women) with pFEA (mean age 51 years, range 29-77 years) were reviewed. Stereotactic CNB was performed in 79 (76%) cases and ultrasound (US)-guided CNB in 25 (24%) cases. In 99 cases 14G needles were used, and 10G vacuum-assisted devices were used in 5 cases. Ninety-four patients had subsequent excision. Ten patients declined excision, and imaging follow-up (mean of 36 months) is available. The upgrade rate of pFEA was defined as the number of patients diagnosed with invasive carcinoma (IC) or carcinoma in situ (CIS) divided by the total number of patients.

RESULTS

10 of 104 (9.6%) patients were diagnosed with cancer: 9 presented as calcifications (89% fine pleomorphic and amorphous) and 1 case as a mammographically occult mass. The size of calcifications was not statistically significant (P=0.358). Five cases had ductal carcinoma in situ (DCIS) and five cases had IC (ductal and lobular) presenting as amorphous and pleomorphic calcifications.

CONCLUSIONS

The upgrade rate of pFEA in our series was 9.6%. The presence of 4.8% of invasive cancers is substantial and warrants continuing management with surgical excision in all cases.

Morphological parameters of flat epithelial atypia (FEA) in stereotactic vacuum-assisted needle core biopsies do not predict the presence of malignancy on subsequent surgical excision

Flat epithelial atypia (FEA) may represent the earliest precursor of low-grade breast cancer and often coexists with more advanced atypical proliferative breast lesions such as atypical ductal hyperplasia (ADH) and lobular intraepithelial neoplasia (LIN). The present study aims to investigate the association between morphological parameters of FEA and presence of malignancy at surgical excision (SE) and the clinical significance of the association of FEA with ADH and/or LIN. This study included 589 cases of stereotactic 11-gauge vacuum-assisted needle core biopsy (VANCB), reporting a diagnosis of FEA, ADH or LIN with subsequent SE from 14 pathology departments in Italy. Available slides were reviewed, with 114 (19.4 %) showing a malignant outcome at SE. Among the 190 cases of pure FEA, no statistically significant association emerged between clinical-pathological parameters of FEA and risk of malignancy. Logistic regression analyses showed an increased risk of malignancy according to the extension of ADH among the 275 cases of FEA associated with ADH (p = 0.004) and among the 34 cases of FEA associated with ADH and LIN (p = 0.02). In the whole series, a statistically significant increased malignancy risk emerged according to mammographic R1-R3/R4-R5 categories (OR = 1.56; p = 0.04), extension (OR = 1.24; p = 0.04) and grade (OR = 1.94; p = 0.004) of cytological atypia of FEA. The presence of ADH was associated with an increased malignancy risk (OR = 2.85; p < 0.0001). Our data confirm the frequent association of FEA with ADH and/or LIN. A diagnosis of pure FEA on VANCB carries a 9.5 % risk of concurrent malignancy and thus warrants follow-up excision because none of the clinical-pathological parameters predicts which cases will present carcinoma on SE.

Pure flat epithelial atypia is uncommon in subsequent breast excisions for atypical epithelial proliferation

The management of atypical intraductal lesions of the breast remains controversial. In the present study, the subsequent surgical excision results and follow-up data on 86 (3.65%) atypical intraductal lesions and 78 (3.31%) low-grade ductal carcinoma in situ (DCIS) from a cohort of 2358 needle biopsies were examined. There were 17 cases (0.72%) of pure flat epithelial atypia (FEA), 44 (1.87%) pure atypical ductal hyperplasia (ADH), three (0.13%) pure atypical lobular hyperplasia (ALH), 18 (0.76%) combined ADH + FEA, three (0.13%) combined ALH + FEA and one (0.04%) combined ALH + FEA + ADH. Subsequent surgical excisions were done in 53 cases and revealed the following incidences of malignancy: pure FEA (1/8); pure ADH (17/31); FEA + ADH (7/10); FEA + ALH (2/3); and FEA + ALH + ADH (0/1), with pure FEA showing significantly lower incidence of malignancy. In this cohort, there were 703 carcinomas including 155 DCIS with 78 cases (50.3%) being low-grade. FEA with ADH (and/or ALH) was present in 22 (28.2%) of these 78 cases of low-grade DCISs at surgical excisions. Pure FEA was not detected in any of the subsequently excised surgical materials of the atypical intraductal lesions nor the low-grade DCISs. Thus, pure FEA was very unusual in surgical specimens. When pure FEA is detected at needle biopsy, a wait and see approach can be adopted. However, when the FEA is associated with other concomitant atypical intraductal lesions, especially ADH, further excision should be contemplated.

Flat epithelial atypia diagnosed on core needle biopsy-Clinical challenge

AIM

This paper describes our experience of 20 cases identified in the FEA vacuum core biopsy.

BACKGROUND

Screening mammography has contributed to the increased recognition of early cancer, premalignant and preinvasive breast lesions. A premalignant lesion called FEA (flat epithelial atypia), although rarely recognized as the only lesion in the core biopsy, is a major challenge in clinical proceedings. Increasing recognition is associated with an increasing use of the vacuum core biopsy as a tool for verifying nonpalpable lesions identified by mammography, and suspected of being breast cancer.

MATERIALS AND METHODS

Of 4326 mammotome biopsies performed at our institution in 2000-2006, FEA was diagnosed in 20 patients (0.46%). These patients underwent surgery for reexcsion. Data were collected for clinical, radiological and pathological findings to assess factors associated with the underestimation of invasive lesions.

RESULTS

Among 20 patients with FEA diagnosis, the mean age was 59.6, range 52-71. When compared to the ADH group (mean age 55.45), the FEA patients were found to be statistically significantly older (p = 0.0002). Two patients 2/20 (10%) showed underestimation, with invasive cancer on the final pathology were G1 tubular cancer T1b, and G2 lobular cancer T1a.

CONCLUSION

Although FEA is rarely diagnosed as the only lesion in a core biopsy, the ever more common use of this diagnostic technique forces us to establish a clear clinical practice. The problem is the underestimation of invasive lesions in the case of primary diagnosis of FEA. It seems that some percent of these cases can be identified by certain radiological or pathological features, thus helping implement appropriate clinical management.

[The lesions of flat epithelial atypia diagnosed on breast biopsy]

Among pre-invasive breast diseases, the lesion of flat epithelial atypia has a level of risk that remains unclear. The clinical significance of these lesions and how to behave during their diagnostic biopsy (monitoring vs. surgery) are still uncertain, because few studies (including monitoring) are available and because of the polymorphic spectrum of lesions and their many denominations across the studies in the literature. This article aims to update our knowledge and provide elements for the management of these lesions diagnosed on breast biopsy.

Outcome of breast lesions diagnosed as lesion of uncertain malignant potential (B3) or suspicious of malignancy (B4) on needle core biopsy, including detailed review of epithelial atypia

AIMS

To provide updated evidence of the outcome of breast lesions of uncertain malignant potential (B3) and suspicious of malignancy (B4) diagnosed on needle core biopsy (NCB) and analyse the outcome of the different types of intraductal epithelial atypia.

METHODS AND RESULTS

One-hundred and forty-nine B3 and 26 B4 NCBs diagnosed over a 2-year period (2007-2008) were compared with those diagnosed over a previous 2-year period (1998-2000). The proportion of B3 diagnoses increased from 3.1% to 4.5%, and the positive predictive value (PPV) of malignancy of a B3 core decreased from 25% to 10%. Increased diagnosis of radial scar and reductions in the PPV of lobular neoplasia and of atypical intraductal proliferation may explain the reduction in the PPV of the B3 group as a whole. There were no significant changes in the proportion of B4 diagnosis (1.1% and 0.8%) or the PPV of B4 (83% and 88%). Review of cores with intraductal atypia showed a wide range of PPVs, from 100% for suspicious of ductal carcinoma in situ, to 40% for atypical ductal hyperplasia categorized as B3, and 14% for isolated flat epithelial atypia.

CONCLUSION

The study has found a decrease in the PPV for a B3 diagnosis and suggests possible explanations.