Distance of Biopsy-Confirmed High-Risk Breast Lesion from Concurrently Identified Breast Malignancy Associated with Risk of Carcinoma at the High-Risk Lesion Site.

High-risk breast lesions including incidental intraductal papilloma without atypia (IPA), lobular hyperplasia (LCIS or ALH), flat epithelial atypia (FEA) and complex sclerosing lesion (CSL) are not routinely excised due to low upgrade rates to carcinoma. We aim to identify features of these lesions predictive of upgrade when identified concurrently with invasive disease. Methods: A single-center retrospective cohort study was performed for patients who underwent multi-site lumpectomies with invasive disease at one site and a high-risk lesion at another site between 2006 and 2021. A multinomial logistic regression was performed. Results: Sixty-five patients met the inclusion criteria. Four patients (6.2%) had an upgrade to in situ disease (DCIS) and one (1.5%) to invasive carcinoma. Three upgraded high-risk lesions were ipsilateral to the concurrent carcinoma and two were contralateral. In the multivariate model, a high-risk lesion within 5 cm of an ipsilateral malignancy was associated with increased risk of upgrade. The 3.8% upgrade rate for high-risk lesions located greater than 5 cm from ipsilateral malignancy or in the contralateral breast suggests that omission of excisional biopsy may be considered. Excisional biopsy of lesions within 5 cm of ipsilateral malignancy is recommended given the 25% upgrade risk in our series.

Updates in the Surgical Management of Benign and High-Risk Breast Lesions.

Benign breast disease (BBD) is a heterogenous group of lesions often classified as nonproliferative or proliferative, with the latter group further categorized based on the presence of atypia. Although nonproliferative lesions are more common, the risk of breast cancer is elevated in women with proliferative lesions. Historically, the majority of proliferative lesions were excised due to concern for future and/or concomitant breast cancer at the site of the index lesion. However, contemporary data suggest that the risk of cancer associated with various proliferative lesions may be lower than previously thought, and management of BBD has become more nuanced. In this review, we will focus on recent updates in the management of a select group of benign and high-risk lesions.

Isolated Flat Epithelial Atypia: Upgrade Outcomes After Multidisciplinary Review-Based Management Using Excision or Imaging Surveillance.

Objective: To compare flat epithelial atypia (FEA) upgrade rates after excision versus surveillance and to identify variables associated with upgrade. Methods: This single-institution retrospective study identified isolated FEA cases determined by percutaneous biopsy from April 2005 through July 2022 with excision or ≥2 years surveillance. All cases were recommended for excision or surveillance based on multidisciplinary discussion of clinical, imaging, and pathologic variables with emphasis on sampling adequacy and significant atypia. Truth was determined by pathology at excision or the absence of cancer on surveillance. Upgrade was defined as cancer occurring ≤2 cm from the biopsy site. Demographic, imaging, and biopsy variables were compared between those that did and did not upgrade. Results: Among 112 cases of isolated FEA, imaging findings included calcifications in 81.3% (91/112), MRI lesions in 11.6% (13/112), and distortions or masses in 7.1% (8/112). Excision was recommended in 12.5% (14/112) and surveillance in 87.5% (98/112) of cases. Among those recommended for excision, 28.6% (4/14) of cases were upgraded, all to ductal carcinoma in situ. In those recommended for surveillance, 1.0% (1/98) were upgraded to invasive cancer. Overall, FEA had a 4.5% (5/112) upgrade rate, and 2.7% (3/112) also developed cancer >2 cm from the FEA. There were no significant differences in demographic, imaging, and biopsy variables between those that did and did not upgrade to cancer. Conclusion: Multidisciplinary management of isolated FEA distinguishes those at higher risk of upgrade to cancer (28.6%) in whom surgery is warranted from those at low risk of upgrade (1.0%) who can be managed non-operatively.

Breast Lesions of Uncertain Malignant Potential (B3) and the Risk of Breast Cancer Development: A Long-Term Follow-Up Study.

Breast lesions of uncertain malignant potential (B3) are frequently diagnosed in the era of breast cancer (BC) screening and their management is controversial. They are generally removed surgically, but some international organizations and guidelines for breast research suggest follow-up care alone or, more recently, propose vacuum-assisted excision (VAE). The risk of upgrade to BC is known, but very little data exist on its role as risk factor for future BC development. We analyzed 966 B3 lesions diagnosed at our institution, 731 of which had long-term follow-up available. Surgical removal was performed in 91%, VAE in 3.8%, and follow-up in 5.2% of cases. The B3 lesions included flat epithelial atypia (FEA), atypical ductal hyperplasia (ADH), lobular intraepithelial neoplasia (LIN), atypical papillary lesions (PLs), radial scars (RSs), and others. Overall, immediate upgrade to BC (invasive or in situ) was 22.7%. After long-term follow-up, 9.2% of the patients were diagnosed with BC in the same or contralateral breast. The highest risk was associated with ADH diagnosis, with 39.8% of patients upgraded and 13.6% with a future BC diagnosis (p < 0.0001). These data support the idea that B3 lesions should be removed and provide evidence to suggest annual screening mammography for women after a B3 diagnosis because their BC risk is considerably increased.

Proliferative epithelial changes in tumour adjacent tissue in Sri Lankan women with breast carcinoma: do morphological changes support molecular models of breast carcinogenesis?

BACKGROUND: The multistep molecular model of breast carcinogenesis is based on the oestrogen receptor(ER) status of the tumour. Its two main arms comprise ER-positive and ER-negative breast carcinomas(BCa), which are associated with Nottingham grade(NG) of the tumour and different proliferative epithelial changes. According to the model, columnar cell lesions(CCL), lobular carcinoma in-situ(LCIS) and atypical ductal hyperplasia(ADH), low-grade ductal carcinoma in-situ (LG-DCIS) are associated with low grade ER-positive tumours and microglandular adenosis (MGA), pleomorphic LCIS(PLCIS), high-grade DCIS(HG-DCIS) are associated with ER-negative high grade tumours. This study aims to describe the association between proliferative epithelial changes in breast tissue adjacent to tumour, in relation to the ER status and NG of the tumour. METHODS: This descriptive cross-sectional study included 420, wide local excision and mastectomy specimens of BCa from National Hospital of Sri Lanka, between 2017-2019. The histopathological features of the tumour and proliferative epithelial changes in tumour adjacent tissue within 10 mm distance from the tumour-host interface were evaluated independently by two pathologists. The ER, PR(Progesterone receptor) and HER2 status assessed by immunohistochemistry(IHC) was reviewed. The associations between above epithelial lesions and ER status and NG{categorised as low grade (NG1 and NG2) and high grade (NG3)} of the tumour were analyzed. RESULTS: ER positive BCa showed significant associations with CCH (p = 0.04), FEA (p = 0.035) and LGDCIS (p < 0.001). Although PLCIS was more frequent in ER positive tumours, the association did not attain statistical significance. ER negative BCa showed a significant association with HGDCIS (p = 0.016). CCLs as a whole (p = 0.005) and also CCC (p = 0.006) and FEA (p = 0.048) and LGDCIS (p < 0.001) showed significant associations with low NG tumours. High NG tumours showed a significant association with HGDCIS (p < 0.001). Microglandular adenosis was not identified in our study population. CONCLUSION: These morphological findings support the multistep molecular based pathogenetic pathways of breast carcinoma in the studied setting in South Asia. Identification of these proliferative epithelial components in a core biopsy that is negative for BCa, should prompt for close clinicoradiological correlation, and if necessary re-biopsy of women suspected of harbouring a BCa.

Risk-Associated Lesions of the Breast in Core Needle Biopsies: Current Approaches to Radiological-Pathological Correlation.

Image-guided core needle biopsies (CNBs) of the breast frequently result in a diagnosis of a benign or atypical lesion associated with breast cancer risk. The subsequent clinical management of these patients is variable, reflecting a lack of consensus on criteria for selecting patients for clinical and radiological follow-up versus immediate surgical excision. In this review, the evidence from prospective studies of breast CNB with radiological-pathological correlation is evaluated and summarized. The data support an emerging consensus on the importance of radiologic-pathologic correlation in standardizing the selection of patients for active surveillance versus surgery.

Rates and Outcomes of Breast Lesions of Uncertain Malignant Potential (B3) benchmarked against the National Breast Screening Pathology Audit; Improving Performance in a High Volume Screening Unit.

INTRODUCTION: Our breast screening unit was identified as high outlier for B3 lesions with a low positive predictive value (PPV) compared to the England average. This prompted a detailed internal audit and review of B3 lesions and their outcomes to identify causes and address any variation in practice. PATIENTS AND METHODS: The B3 rate was calculated in 4168 breast core biopsies from 2019, using the subsequent excision to determine the PPV. Atypical intraductal epithelial proliferation (AIDEP) cases were subject to microscopic review to reassess the presence of atypia against published criteria. The B3 rate was re-audited in 2021, and the results compared. RESULTS: Screening cases had a high B3 rate of 12.4% (30% above the national average), and a PPV of 7.7% (9.7% with atypia). AIDEP was identified as a possible cause of this outlier status. On review and by consensus, AIDEP was confirmed in only 66% of cases reported as such, 17% were downgraded, and 16% did not reach consensus, the latter highlighting the difficulty and subjectivity in diagnosis of these lesions. Repeat audit of B3 rates after this extended review revealed a reduction from 12.4% to 9.11%, which is more in line with national standards. CONCLUSION: Benchmarking against national reporting standards is critical for service improvement. Through a supportive environment, team working, rigorous internal review and adherence to guidelines, interobserver variation and outlier status in breast pathology screening outliers can both be addressed. This study can serve as a model to other outlier units to identify and tackle underlying causes.

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%.

Management of high-risk breast lesions diagnosed on core biopsies and experiences from prospective high-risk breast lesion conferences at an academic institution.

BACKGROUND: The management of high-risk breast lesions diagnosed on image-guided core biopsy remains controversial. We implemented a high-risk breast conference attended by breast pathologists, imagers, and surgeons to prospectively review all contemporary cases in order to provide a consensus recommendation to either surgically excise or follow on imaging at 6-month intervals for a minimum of 2 years. METHODS: Between May, 2015 and June, 2019, 127 high-risk lesions were discussed. Of these 127 cases, 116 had concordant radiology-pathology (rad-path) findings. The remaining 11 patients had discordant rad-path findings. Of the 116 concordant cases, 6 were excluded due to lack of the first imaging follow-up until analysis. Of the remaining 110 patients, 43 had atypical ductal hyperplasia (ADH), 12 had lobular carcinoma in situ (LCIS), 19 had atypical lobular hyperplasia (ALH), 33 had radial scar (RS), 2 had flat epithelial atypia (FEA), and 1 had mucocele-like lesion (ML). We recommended excision for ADH if there were > 2 ADH foci or < 90% of the associated calcifications were removed. For patients with LCIS or ALH, we recommended excision if the LCIS or ALH was associated with microcalcifications or the LCIS was extensive. We recommended excision of RS when < 1/2 of the lesion was biopsied. We recommended all patients with FEA and ML for 6-month follow-up. RESULTS: Following conference-derived consensus for excision, of the 27 ADH excised, 9 were upgraded to invasive carcinoma or ductal carcinoma in situ. Of the six LCIS cases recommended for excision, none were upgraded. Nine excised radial scars revealed no upgrades. Additionally, 3 patients with ADH, 2 with ALH, 1 with LCIS, and 2 with RS underwent voluntary excision, and none were upgraded. All other patients (13 with ADH, 5 LCIS, 17 ALH, 22 RS, 2 FEA and 1 ML) were followed with imaging, and none revealed evidence of disease progression during follow-up (187-1389 days). All 11 rad-path discordant cases were excised with 2 upgraded to carcinoma. CONCLUSIONS: The results of this prospective study indicate that high-risk breast lesions can be successfully triaged to surgery versus observation following establishment of predefined firm guidelines and performance of rigorous rad-path correlation.

Management of High-Risk Breast Lesions.

High-risk breast lesions (HRLs) are a group of heterogeneous lesions that can be associated with a synchronous or adjacent breast cancer and that confer an elevated lifetime risk of breast cancer. Management of HRLs after core needle biopsy may include close imaging and clinical follow-up or excisional biopsy to evaluate for cancer. This article reviews histologic features and clinical presentation of each of the HRLs, current evidence with regard to management, and guidelines from the American Society of Breast Surgeons and National Comprehensive Cancer Network. In addition, imaging surveillance and risk-reduction strategies for women with HRLs are discussed.

Breast Cancer and Secondary Cancer Recurrences After Autologous Tissue Reconstruction.

BACKGROUND: The medical literature defining breast cancer recurrence and secondary cancers after autologous tissue reconstruction for breast cancer is sparse. We sought to identify and analyze occurrences at our institution. PATIENTS AND METHODS: A 20-year retrospective review of cancer recurrences and atypical breast neoplasms after autologous tissue breast reconstruction at Roswell Park Comprehensive Cancer Center was conducted after being granted a waiver from the institutional review board. RESULTS: Eighteen locoregional recurrences among 337 cases were identified and analyzed. Overall recurrence rate was 5.3%. Four secondary cancers (1.2%) were radiation-induced angiosarcoma, undifferentiated pleomorphic sarcoma, and metaplastic carcinoma. One case of flat epithelial atypia was identified. CONCLUSION: Our retrospective review found incidence and survival after treatment of breast cancer concordant with reports in the literature. We also identified and analyzed secondary neoplasms, including a unique case of undifferentiated pleomorphic sarcoma and metachronous recurrence of breast carcinoma. A case of recurrence as metaplastic carcinoma was identified.

Preneoplasia of the Breast and Molecular Landscape.

The current model of human breast cancer progression proposes a linear multi-step process which initiates as flat epithelial atypia (FEA), progresses to atypical ductal hyperplasia (ADH), evolves into ductal carcinoma in situ (DCIS) and culminates in the potentially lethal stage of invasive ductal carcinoma. FEA commonly coexists with well-developed examples of ADH, low-grade DCIS, lobular neoplasia and tubular carcinoma. These findings and those of recent genetic studies suggest that FEA is a neoplastic lesion that may represent a precursor to or the earliest morphologic manifestation of ductal carcinoma in situ. At the same time, many of the genomic changes of ADH are also shared by common sporadic breast cancer, consistent with a high risk for future development of metachronous breast cancer.

Is Excisional Biopsy Needed for Pure FEA Diagnosed on a Core Biopsy?

BACKGROUND: The management of flat epithelial atypia (FEA) on core needle biopsy remains controversial. The upstaging rates after surgical excision are variable. In this study, we seek to determine the upstaging rate of FEA at our institution. METHODS: Patients with a diagnosis of FEA were identified from the institution's pathology database from 2009 to 2018. Patients were included in the study if FEA alone, without atypia or cancer, was identified on core needle biopsy. Patient demographics, imaging, management, and pathology characteristics were obtained. Statistical analysis performed using IBM SPSS 26.0 (Armonk, NY, USA). RESULTS: FEA was diagnosed on core needle biopsy in 235 patients from 2009 to December 2018. Forty-eight patients met the inclusion criteria. The majority of patients presented with calcifications on mammogram (n = 21, 64%) with the remainder as masses (n = 6, 18%) or architectural distortion (n = 6, 18%). Of those, 15 (31%) patients declined surgical excision, of which none developed cancer over a mean follow-up of 4.4 years. Of the 33 (69%) patients undergoing excisional biopsy, 17 (52%) confirmed FEA, 11 (33%) had benign findings, and 3 (9%) demonstrated atypical ductal hyperplasia on final pathology. One (3%) case revealed ductal carcinoma in situ (DCIS) and 1 (3%) was upgraded to invasive cancer for an overall upstaging rate of 4% (2/48). After a mean follow-up of 3.4 years, none of the excisional biopsy patients developed invasive breast cancer. Adjuvant therapy was used in the cases of DCIS and invasive cancer; however, chemoprevention with raloxifene or tamoxifen was not chosen by any of the remaining patients. CONCLUSION: In our cohort, expectant management of FEA alone appears to be a safe option as our upstaging rate to DCIS or invasive cancer for FEA diagnosed on core biopsy was only 4%. Our study suggests that close follow-up is a safe and feasible option for pure FEA without a radiographic discordance found on core biopsy.

Pure flat epithelial atypia identified on core needle biopsy does not require excision.

BACKGROUND: Routine excision of flat epithelial atypia (FEA) of the breast found on core needle biopsy (CNB) is being questioned and a policy of selective excision of FEA was adopted in our area. The purpose of this study was to evaluate the upstage rate to malignancy across multiple diagnostic centers in our area following the policy of selective excision and to identify factors predictive of malignancy. METHODS: Patients having excision of CNB FEA at our regional Hospital between 2013 and 2017 were identified. The primary endpoint was upstage to malignancy after excision. We also assessed for clinical, radiological, and pathological features associated with malignancy. RESULTS: We identified 187 patients. Eighty-nine had pure FEA, 71 had concurrent ADH, and 18 had other pathological lesions. Following surgical excision, 9 patients were upstaged to malignancy (4. 8%) with 8 having concurrent ADH (2 invasive ductal carcinoma, 6 DCIS) and 1 with concurrent Complex Sclerosing Lesion (DCIS). None of the pure FEA cases upstaged. The presence of ADH or CSL in the CNB were the only factors found to be predictive of upstaging (p = 0.001, p = 0.0001 respectively). CONCLUSIONS: The upstage rate to malignancy after excision of pure FEA at out center is 0%. Therefore, we recommend that pure FEA with radiology and pathology concordance does not require surgical excision and can instead be followed with serial imaging. However, patients with FEA in association with other high-risk lesions should be managed as per indicated for the other high-risk lesion and FEA with ADH should be excised.

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

Flat Epithelia Atypia (FEA) is a proliferative lesion of the breast where cells demonstrate columnar change and cytologic atypia. This lesion has been identified as distinct from the classic atypical hyperplasias (AH). While many patients undergo excisional biopsy, management of FEA identified on core needle biopsy (CNB) is controversial, and the rate of associated ductal carcinoma in situ (DCIS) or invasive cancer is not well defined. The aim of this study was to determine the upstage rate of FEA diagnosed by CNB. We identified patients from a prospectively maintained data base who had FEA diagnosed by CNB from 01/2010 to 07/2015. Patient variables collected included age at presentation, imaging findings, pathologic findings following surgical excision, and subsequent development of breast cancer. Of 132 patients, 62 (n = 62/132, 47.0%) patients had FEA associated with DCIS and invasive ductal carcinoma (IDC) on CNB and were excluded from analysis. Of the remaining 70 patients, median age was 52 (range 31-84) years. Thirty-two (45.7%) patients had FEA plus AH, 4 (5.7%) patients had FEA plus lobular carcinoma in situ (LCIS), and 34 (48.6%) patients had FEA alone or with another non-pathologic finding (pure FEA). Two (6.3%) patients with FEA plus AH had DCIS or IDC on subsequent excisional biopsy. Of the 34 patients with pure FEA who underwent excisional biopsy, only one (2.9%) was found to have IDC. Twenty-two (64.7%) patients with pure FEA who underwent excisional biopsy presented with calcifications on mammography. None of these patients had cancer on excisional biopsy, and 10 (45.5%) patients had AH (3 ADH, 3 ALH, and 4 both ALH and ADH). Twelve (n = 12/34, 35.3%) patients with pure FEA underwent CNB for a mass or asymmetry noted on imaging. Of these 12 patients, 9 (75.0%) had benign findings on excisional biopsy, two (16.7%) patients had AH, and one (8.3%) patient had IDC. Median follow-up was 4.6 years (IQR 3.1-6.5 years). Three (4.3%) patients subsequently developed IDC, two of which were in the contralateral breast. FEA is often found in combination with ADH and ALH as well as carcinoma on CNB. In our study, pure FEA was upstaged to cancer in only 2.9% of patients. Mammographic findings unlikely predict upstaging to malignancy. These findings suggest that excisional biopsy may not be warranted in patients with pure FEA and could be managed with close imaging surveillance.

Flat epithelial atypia: are we being too aggressive?

PURPOSE: The malignant upgrade rate of flat epithelial atypia (FEA) diagnosed on core needle biopsy varies between 0 and 30%. Excision versus observation with radiological follow-up for these lesions remains controversial. We hypothesize that the local rate of FEA is low and that close radiological surveillance is a reasonable treatment option for patients diagnosed with pure FEA on breast needle core needle biopsy. METHODS: This study was a retrospective review of a prospectively collated provincial pathology database. Patients diagnosed with FEA alone on needle core biopsy between 2006 and 2016 were included in our analysis. Patients who had FEA present together with either in situ or invasive carcinoma within the same biopsy cores were excluded. Along with patient demographics, the size of the lesion on preoperative imaging, the method of extraction, and the presence of co-existing benign and malignant pathology on final excision biopsy were analyzed. An independent pathological review was performed to confirm our results and help reduce inter-observer bias. RESULTS: The local rate of malignant upgrade when pure FEA is diagnosed on a breast needle core biopsy is 12%. Age at time of diagnosis, size of original lesion on mammogram, presence of atypical ductal hyperplasia (ADH) or atypical lobular hyperplasia on core needle biopsy, the use of vacuum-assisted biopsy (VAB), or concordant imaging did not significantly correlate with malignant upgrade risk. None of the patients who were managed with radiological follow-up had malignant upgrade during follow-up. Patients undergoing radiological follow-up alone were more likely to have a VAB, concordant imaging, and no concurrent ADH. CONCLUSION: Our local malignant upgrade rate is consistent with published literature. We suggest radiological follow-up is a safe alternative in patients with pure flat epithelial atypia and concordant imaging, particularly those patients with small lesions in which microcalcifications can be removed completely with vacuum-assisted biopsy.

Upgrade Rate of Flat Epithelial Atypia Diagnosed at Stereotactic Core Needle Biopsy of Microcalcifications: Is Excisional Biopsy Indicated?

OBJECTIVE: Whether the optimal management of pure flat epithelial atypia (FEA) found on core needle biopsy (CNB) specimens is surgical excision or imaging follow-up remains controversial. This study aimed to determine the upgrade rate to ductal carcinoma in situ (DCIS), invasive carcinoma or a high-risk lesion (atypical ductal hyperplasia, atypical lobular hyperplasia, or lobular carcinoma in situ), and it explored the relationship between a family history of breast cancer and the risk of upgrade. METHODS: Cases with pure FEA found on stereotactic CNB of microcalcifications between March 2011 to December 2017 were followed by excisional biopsy or periodic imaging. The proportion of cases upgraded to a high-risk lesion and the odds of upgrade as related to a family history of breast cancer were determined with 95% confidence intervals (CIs). RESULTS: We identified 622 cases of pure FEA; 101 (16.2%) underwent surgical excision and 269 (43.2%) had imaging follow-up of ≥ 24 months. There were no upgrades to DCIS or invasive cancer in any of these 370 individuals (0%), and 4.6% (17/370; 95% CI: 2.9%-7.2%) were upgraded to a high-risk lesion. There was a nonstatistically significant trend between family history and upgrade to high-risk lesion (odds ratio 1.72 [95% CI: 0.65%-4.57%]). CONCLUSION: In our study, the upgrade rate of pure FEA to malignancy was 0%. We suggest that regular imaging follow-up is an appropriate alternative to surgery. Because of potential differences in biopsy techniques and pathologist interpretation of the primary biopsy, individual institutions should audit their own results prior to altering their management of FEA.

Breast lesions with atypia in percutaneous biopsies, managed with surgery in the last 10 years.

INTRODUCTION: The optimal management of breast lesions with atypia (BLA), detected in percutaneous biopsies after screening mammograms, is a controversial issue. The aim of this paper is to compare histological diagnosis by percutaneous biopsy with the results of the surgical biopsy of these lesions and to analyse the changes to clinical approach this would imply. METHOD: A retrospective study was carried out on patients operated on between June 2007 and June 2017 with a diagnosis of BLA. One hundred and forty-seven patients were identified with a pre-operative diagnosis of flat epithelial atypia (FEA), atypical ductal hyperplasia (ADH), atypical lobular hyperplasia, lobular carcinoma in situ and other atypia. RESULTS: The average age at diagnosis of BLAs was 52 ± 9.4 years. Radiologically, the lesions presented as microcalcifications in 79%, nodules in 15.6% and other lesions 5.4%. 73.5% of these were biopsied by means of digital stereotaxis. All of the patients analysed underwent a partial mastectomy. Changes in a biologically high-risk lesion were observed in 26.5% of the surgical specimens, of which 75.5% corresponded with ADH and FEA. In the percutaneous biopsies consistent with ADH (40.1%), ductal carcinoma was discovered in 6.8% (5.1% in situ and 1.7% invasive), which implied specific, multi-disciplinary management. Of the FEAs, 84.8% required a second treatment (surgery and/or hormone therapy ± radiotherapy, depending on whether it concerned FEA 59.6%, ADH 21.2% or ductal carcinoma in situ 3.8%). CONCLUSION: These data show the clinical relevance in the diagnosis of ADH and FEA in percutaneous biopsies. For the diagnosis of FEA in particular, the associated risk of biologically high-risk lesions and ductal carcinoma is made evident.

Diagnostic terminology used to describe atypia on breast core needle biopsy: correlation with excision and upgrade rates.

BACKGROUND: Subjective qualitative descriptors are sometimes used to describe atypical breast lesions diagnosed on core needle biopsy (CNB) which are limited in extent. In clinical practice, this terminology is used to imply a lower expected risk of upgrade on surgical excision (EXC). It is uncertain how subjective terminology impacts clinical management. METHODS: We conducted a retrospective review of CNB with atypia and compared the EXC and upgrade rates of atypical ductal hyperplasia (ADH) and flat epithelial atypia (FEA) to lesions described as "focal" atypical ductal hyperplasia (FADH), to determine the impact of this diagnostic phrasing on surgical management and risk of malignancy. RESULTS: FADH and ADH were excised at similar rates (82% vs. 78%). FADH lesions showed a similar upgrade rate (13%) compared to non-focal ADH (10%), and both showed a trend towards higher upgrade and EXC rates compared to FEA. ADH, FADH and FEA all had an upgrade risk that warranted EXC. In non-upgraded EXC, for each diagnostic category we observed similar rates of residual atypia in the EXC. CONCLUSIONS: Pathologists should avoid the use of qualitative descriptors when describing ADH on CNB because of the potential of this terminology to influence clinical decision making which is unwarranted.

Isolated Flat Epithelial Atypia on Core Biopsy Specimens Is Associated With a Low Risk of Upgrade at Excision.

OBJECTIVES: We present a retrospective review of 111 breast core biopsy specimens with flat epithelial atypia (FEA) and corresponding excision to better understand rates of upgrade following this diagnosis. METHODS: In total, 252 breast core biopsy specimens were identified. Cases were excluded if biopsy slides or excision results were unavailable, for ipsilateral carcinoma or other findings warranting excision, or biopsy performed for indications other than mammographically detected calcifications. Coincident atypical lobular hyperplasia was not excluded. Diagnoses were confirmed by breast pathologists, and mammographic images were reviewed. RESULTS: Ultimately, 111 biopsy specimens with FEA were included. In subsequent excisions, one (1%) of 111 showed invasive carcinoma, 20 (18%) atypical ductal hyperplasia, 20 (18%) lobular neoplasia, 31 (28%) FEA, and 39 (35%) no atypical findings. CONCLUSIONS: FEA on core biopsy specimens is associated with a low rate of upgrade to invasive carcinoma. Close follow-up may be a reasonable alternative to excision for isolated FEA on core needle biopsy specimens.