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.

Upgrade Rates and Breast Cancer Development Among Germline Pathogenic Variant Carriers with High-Risk Breast Lesions

BACKGROUND

High-risk lesions (HRL) of the breast are risk factors for future breast cancer development and may be associated with a concurrent underlying malignancy when identified on needle biopsy; however, there are few data evaluating HRLs in carriers of germline pathogenic variants (PVs) in breast cancer predisposition genes.

METHODS

We identified patients from two institutions with germline PVs in high- and moderate-penetrance breast cancer predisposition genes and an HRL in an intact breast, including atypical ductal hyperplasia (ADH), flat epithelial atypia (FEA), and lobular neoplasia (LN). We calculated upgrade rates at surgical excision and used Kaplan-Meier methods to characterize 3-year breast cancer risk in patients without upgrade.

RESULTS

Of 117 lesions in 105 patients, 65 (55.6%) were ADH, 48 (41.0%) were LN, and 4 (3.4%) were FEA. Most PVs (83.8%) were in the BRCA1/2, CHEK2 and ATM genes. ADH and FEA were excised in most cases (87.1%), with upgrade rates of 11.8% (95% confidence interval [CI] 5.5-23.4%) and 0%, respectively. LN was selectively excised (53.8%); upgrade rate in the excision group was 4.8% (95% CI 0.8-22.7%), and with 20 months of median follow-up, no same-site cancers developed in the observation group. Among those not upgraded, the 3-year risk of breast cancer development was 13.1% (95% CI 6.3-26.3%), mostly estrogen receptor-positive (ER +) disease (89.5%).

CONCLUSIONS

Upgrade rates for HRLs in patients with PVs in breast cancer predisposition genes appear similar to non-carriers. HRLs may be associated with increased short-term ER+ breast cancer risk in PV carriers, warranting strong consideration of surgical or chemoprevention therapies in this population.

Lobular Neoplasia Diagnosed by MRI-Guided Breast Biopsy: Identifying Upgrade Rate to Malignancy and Outcomes of Clinical and Surgical Management

OBJECTIVE

The aim of this study was to determine surgical and clinical outcomes of lobular neoplasia (LN) diagnosed by magnetic resonance imaging (MRI) biopsy, including upgrade to malignancy, and to assess for characteristics associated with upgrade.

METHOD

A single-institution retrospective study, between 2013 and 2022, of patients with histopathological findings of LN via MRI-guided biopsy was performed using an institutional database and review of the electronic medical records. Decision for excision or surveillance was made by a multidisciplinary team per institutional practice. Patient demographics and imaging characteristics were summarized using descriptive analyses. Upgrade was defined as upgrade to cancer on surgical pathology for patients treated with excision or the development of cancer at the biopsy site during surveillance. The Wilcoxon rank-sum test and Fisher's exact test were used to compare features of the upgraded cohort with the remainder of the group.

RESULTS

Ninety-four MRI biopsies diagnosing LN were included. Median age was 57 years (range 37-78 years). Forty-six lesions underwent excision while 48 lesions were surveilled. The upgrade rate was 7.4% (7/94). Upgrades in the excised cohort consisted of pleomorphic lobular carcinoma in situ (LCIS; n = 1), ductal carcinoma in situ (DCIS; n = 3) and invasive lobular carcinoma (ILC; n = 2), while one interval development of DCIS was observed at the site of biopsy in the surveillance cohort. No MRI or patient variables were associated with upgrade.

CONCLUSIONS

In this contemporary cohort of MRI-detected LNs, the upgrade rate was low. Omission of surgery for MRI-detected LNs in carefully selected patients may be considered in a shared decision-making capacity between the patient and the treatment team. Larger cohorts are needed to determine factors predictive of upgrade risk.

Upgrade Rates of Variant Lobular Carcinoma In Situ Compared to Classic Lobular Carcinoma In Situ Diagnosed in Core Needle Biopsies: A 10-Year Single Institution Retrospective Study

The primary aim of this study was to determine the upgrade rates of variant lobular carcinoma in situ (V-LCIS, ie, combined florid [F-LCIS] and pleomorphic [P-LCIS]) compared with classic LCIS (C-LCIS) when diagnosed on core needle biopsy (CNB). The secondary goal was to determine the rate of progression/development of invasive carcinoma on long-term follow-up after primary excision. After institutional review board approval, our institutional pathology database was searched for patients with "pure" LCIS diagnosed on CNB who underwent subsequent excision. Radiologic findings were reviewed, radiologic-pathologic (rad-path) correlation was performed, and follow-up patient outcome data were obtained. One hundred twenty cases of LCIS were identified on CNB (C-LCIS = 97, F-LCIS = 18, and P-LCIS = 5). Overall upgrade rates after excision for C-LCIS, F-LCIS, and P-LCIS were 14% (14/97), 44% (8/18), and 40% (2/5), respectively. Of the total cases, 79 (66%) were deemed rad-path concordant. Of these, the upgrade rate after excision for C-LCIS, F-LCIS, and P-LCIS was 7.5% (5 of 66), 40% (4 of 10), and 0% (0 of 3), respectively. The overall upgrade rate for V-LCIS was higher than for C-LCIS (P = .004), even for the cases deemed rad-path concordant (P value: .036). Most upgraded cases (23 of 24) showed pT1a disease or lower. With an average follow-up of 83 months, invasive carcinoma in the ipsilateral breast was identified in 8/120 (7%) cases. Six patients had died: 2 of (contralateral) breast cancer and 4 of other causes. Because of a high upgrade rate, V-LCIS diagnosed on CNB should always be excised. The upgrade rate for C-LCIS (even when rad-path concordant) is higher than reported in many other studies. Rad-path concordance read, surgical consultation, and individualized decision making are recommended for C-LCIS cases. The risk of developing invasive carcinoma after LCIS diagnosis is small (7% with ∼7-year follow-up), but active surveillance is required to diagnose early-stage disease.

Does Non-Classic Lobular Carcinoma In Situ at the Lumpectomy Margin Increase Local Recurrence?

BACKGROUND

The clinical significance of nonclassic, lobular carcinoma in situ (NC-LCIS) at the surgical margin of excisions for invasive cancer is unknown. We sought to determine whether NC-LCIS at or near the margin in the setting of a concurrent invasive carcinoma is associated with risk of ipsilateral breast tumor recurrence (IBTR) and locoregional recurrence (LRR).

METHODS

Patients with stage 0-III breast cancer and NC-LCIS who underwent lumpectomy between January 2010 and January 2022 at a single institution were retrospectively identified. NC-LCIS margins were stratified as <2 mm, ≥2 mm, or within shave margin. Rates of IBTR and LRR were examined.

RESULTS

A total of 511 female patients (median age 60 years [interquartile range (IQR) 52-69]) with NC-LCIS and an associated ipsilateral breast cancer with a median follow-up of 3.4 years (IQR 2.0-5.9) were identified. Final margins for NC-LCIS were ≥2 mm in 348 patients (68%), <2 mm in 37 (7.2%), and within shave margin in 126 (24.6%). Crude incidence of IBTR was 3.3% (n = 17) and that of LRR was 4.9% (n = 25). There was no difference in the crude rate of IBTR by NC-LCIS margin status (IBTR rate: 3.7% ≥2 mm, 0% <2 mm, 3.2% within shave margin, p = 0.8) nor in LRR (LRR rate: 4.9% ≥2 mm, 2.7% <2 mm, 5.6% within shave margin, p = 0.9).

CONCLUSIONS

For completely excised invasive breast cancers associated with NC-LCIS, extent of margin width for NC-LCIS was not associated with a difference in IBTR or LRR. These data suggest that the decision to perform reexcision of margin after lumpectomy should be driven by the invasive cancer, rather than the NC-LCIS margin.

Prevalence, Impact, and Diagnostic Challenges of Benign Breast Disease: A Narrative Review

Benign breast diseases, which are commonly seen in clinical practice, have various clinical presentations and implications, as well as management strategies. This article describes common benign breast lesions, presentations of these lesions, and typical radiographic and histologic findings. Also included in this review are the most recent data and guideline-based recommendations for the management of benign breast diseases at diagnosis, including surgical referral, medical management, and ongoing surveillance.

Management of Lobular Neoplasia Diagnosed by Core Biopsy

Lobular neoplasia (LN) involves proliferative changes within the breast lobules. LN is divided into lobular carcinoma in situ (LCIS) and atypical lobular hyperplasia (ALH). LCIS can be further subdivided into three subtypes: classic LCIS, pleomorphic LCIS, and LCIS with necrosis (florid type). Because classic LCIS is now considered as a benign etiology, current guidelines recommend close follow-up with imaging versus surgical excision. The goal of our study was to determine if the diagnosis of classic LN on core needle biopsy (CNB) merits surgical excision. This is a retrospective, observational study conducted at Mount Auburn Hospital, Cambridge, MA, from May 17, 2017, through June 30, 2020. We reviewed the data of breast biopsies conducted at our hospital over this period and included patients who were diagnosed with classic LN (LCIS and/or ALH) and excluded patients having any other atypical lesions on CNB. All known cancer patients were excluded. Of the 2707 CNBs performed during the study period, we identified 68 women who were diagnosed with ALH or LCIS on CNB. CNB was performed for an abnormal mammogram in the majority of patients (60; 88%) while 7(10.3%) had an abnormal breast magnetic resonance imaging study (MRI), and 1 had an abnormal ultrasound (US). A total of 58 patients (85%) underwent excisional biopsy, of which 3 (5.2%) showed malignancy, including 2 cases of DCIS and 1 invasive carcinoma. In addition, there was 1 case (1.7%) with pleomorphic LCIS and 11 cases with ADH (15.5%). The management of LN found on core biopsy is evolving, with some advocating surgical excision and others recommending observation. Our data show a change in diagnosis with excisional biopsy in 13 (22.4%) of patients with 2 cases of DCIS, 1 invasive carcinoma, 1 pleomorphic LCIS, and 9 cases of ADH, diagnosed on excisional biopsy. While ALH and classic LCIS are considered benign, the choice of ongoing surveillance versus excisional biopsy should be made with shared decision making with the patient, with consideration of personal and family history, as well as patient preferences.

High-risk and selected benign breast lesions diagnosed on core needle biopsy: Evidence for and against immediate surgical excision

The vast majority of image-detected breast abnormalities are diagnosed by percutaneous core needle biopsy (CNB) in contemporary practice. For frankly malignant lesions diagnosed by CNB, the standard practice of excision and multimodality therapy have been well-defined. However, for high-risk and selected benign lesions diagnosed by CNB, there is less consensus on optimal patient management and the need for immediate surgical excision. Here we outline the arguments for and against the practice of routine surgical excision of commonly encountered high-risk and selected benign breast lesions diagnosed by CNB. The entities reviewed include atypical ductal hyperplasia, atypical lobular hyperplasia, lobular carcinoma in situ, intraductal papillomas, and radial scars. The data in the peer-reviewed literature confirm the benefits of a patient-centered, multidisciplinary approach that moves away from the reflexive "yes" or "no" for routine excision for a given pathologic diagnosis.

Risk of Lobular Neoplasia Upgrade with Synchronous Carcinoma

BACKGROUND

Atypical lobular hyperplasia (ALH) and classic lobular carcinoma in situ encompass a spectrum of proliferative lesions known as lobular neoplasia (LN). When imaging-concordant and found in isolation on core needle biopsy (CNB), LN infrequently upgrades to carcinoma on surgical excision, and routine excision is not indicated. Upgrade rates in the setting of synchronous carcinoma are not well studied.

PATIENTS AND METHODS

Patients with radiology-pathology concordant synchronous LN and separately biopsied ipsilateral (n = 35) or contralateral (n = 15) carcinoma who underwent excision between 2010 and 2021 were retrospectively identified. Frequency of upgrade, to either invasive or in situ carcinoma, was quantified, and factors associated with upgrade were assessed using Fisher's exact test.

RESULTS

The median age was 55 (range 33-74) years. The upgrade rate of LN was 6% and not significantly different between ipsilateral (2.9%) and contralateral (13.3%) carcinoma (p = 0.15). All upgraded LN lesions were ALH on CNB and detected as non-mass enhancement on magnetic resonance imaging (MRI). No additional disease was demonstrated after excision at the site of the original LN CNB in 22.9% (8 out of 35) of ipsilateral and 13.3% (2 out of 15) of contralateral patients. Upgrade was not associated with family history, menopausal status, imaging modality used to detect LN, or extent of LN on CNB (p > 0.05).

CONCLUSIONS

Our results demonstrate a low upgrade rate (6%) in our study cohort of LN with synchronous ipsilateral or contralateral carcinoma, which suggests that not all LN mandates excision with synchronous carcinoma. Larger, multi-institution studies are needed to validate these findings.

Upgrade Rates of Pure, Radiology-Pathology Concordant Lobular Neoplasia Diagnosed on Breast Core Needle Biopsy: Is Surgical Excision Warranted?

OBJECTIVE

To determine upgrade rates of lobular neoplasia (LN) to malignancy and evaluate factors that may predict upgrade.

METHODS

From 5/1/2003 to 12/30/2015, breast lesions diagnosed as LN (atypical lobular hyperplasia [ALH] or classic lobular carcinoma in-situ [LCIS]) on core biopsy that underwent surgical excision or at least 2 years imaging follow-up were identified. A subspecialty trained breast radiologist and pathologist reviewed imaging and pathology slides to confirm diagnosis and to determine if LN represented the target lesion, part of the target lesion, or an incidental finding. Imaging features, original BI-RADS final assessment category, biopsy method, biopsy device and final pathologic diagnosis were documented. Cases with both ALH and LCIS were classified as LCIS for analysis. Reason for biopsy of BI-RADS 2-3 was patient or referring physician preference. Upgrade rates to malignancy were determined for all cases.

RESULTS

In this study 73.7% (115/156) lesions were ALH and 26.3% (41/156) were LCIS+/-ALH. Surgical excision and imaging follow-up were performed in 71.2% (111/156) and 28.8% (45/156), respectively. Upgrade rates for ALH and LCIS were 0.0% (0/115) and 7.3% (3/41), respectively. Cancer developed at a site separate from core biopsy in 1.7% (2/115) ALH and 7.3% (3/41) LCIS cases. We found no association of upgrade rate with biopsy type, BI-RADS or target/part of target lesion versus incidental.

CONCLUSION

Our study supports consideration of excision for LCIS, given 7.3% upgrade rate. Conversely, imaging surveillance might be appropriate following diagnosis of ALH alone.

The positive predictive value of vacuum assisted biopsy (VAB) in predicting final histological diagnosis for breast lesions of uncertain malignancy (B3 lesions): A systematic review & meta-analysis

INTRODUCTION

High-risk or B3 breast lesions are considered lesions of uncertain malignant potential and comprise between 5 and 12% of initial biopsy results. We sought to perform a systematic review and meta-analysis of studies published within the last twenty years to determine the pooled Positive Predictive Value (PPV) of VAB in selected B3 lesions.

METHODS

The study report is based on the guidelines of PRISMA and Meta-Analysis of Observational Studies in Epidemiology.

OUTCOMES

The primary outcome of this study was to determine the PPV of VAB in determining final histological diagnosis in B3 breast lesions using pooled estimates. The secondary outcomes were to determine if needle gauge or the re-classification of Lobular Carcinoma in Situ(LCIS) introduced in 2012 influenced pooled estimates.

RESULTS

78 studies incorporating 6,377 B3 lesions were included in this review, 1214 of which were upgraded to DCIS or invasive malignancy following surgical excision(19%). The pooled PPV of VAB in Atypical Ductal Hyperplasia(ADH) and Lobular Neoplasia(LN) were 0.79(CI 0.76-0.83) and 0.84(CI 0.8-0.88). VAB of Flat Epithelial Atypia(FEA), radial scar and papillary lesions with/without atypia all had a pooled PPV >90% (underestimation rates 7%, 1%, 5% and 3% respectively). Needle gauge size and the change in LCIS classification did not appear to influence underestimation rates on subgroup analysis.

CONCLUSION

Results from this meta-analysis suggests it is reasonable to perform VAB as definitive treatment for certain B3 lesions, specifically LN, FEA, radial scar, and papillary lesions when specific criteria are fulfilled. Surgical excision should continue as the mainstay of treatment for ADH.

Comparison of Outcomes for Classic-Type Lobular Carcinoma In Situ Managed with Surgical Excision After Core Biopsy Versus Observation

BACKGROUND

Studies report low upgrade rates following excision for classic-type lobular carcinoma in situ (LCIS) with radiologic-pathologic concordance. Thus, in the absence of other high-risk lesions, observation has become standard. We report long-term outcomes of excision versus observation following a core biopsy diagnosis of classic-type LCIS.

METHODS

Women with LCIS treated from 2013-2020 and managed with excision or observation were identified from a prospective database. Women with cancer upgrade at excision or history of cancer were excluded. We compared rates and characteristics of subsequent breast cancers by clinical management strategy.

RESULTS

Of 312 women, 170 (54%) underwent excision and 142 (46%) were managed with observation. Among the excision group, 36 of 170 (21%) had radiologic-pathologic concordant LCIS without other high-risk lesions, mass, or symptoms (concordant LCIS excision group). Overall, at 3.1 years median follow-up, 11 (6.5%) women managed with excision and 11 (7.7%) women managed with observation developed cancer. Cancer development was not associated with management choice (overall excision cohort vs. observation group [p = 0.8]) and did not differ between the concordant LCIS excision and observation groups (p > 0.9). The 5-year cancer development rate was 8.9% (95% confidence interval [CI]: 2.3-31.6%) in the concordant LCIS excision group and 10.3% (95% CI 5.5-18.6%) in the observation group.

CONCLUSIONS

No difference in breast cancer rates existed among women with a core-biopsy diagnosis of classic-type LCIS managed with excision or observation. These data support management of LCIS as a risk factor, with consideration of chemoprophylaxis, rather than as an indication for surgical excision.

Updates on Lobular Neoplasms, Papillary, Adenomyoepithelial, and Fibroepithelial Lesions of the Breast

CONTEXT.—

This review article is a result of the breast pathology lectures given at the Sixth Chinese American Pathologists Association annual diagnostic pathology course in October 2020 (held virtually due to the coronavirus disease 2019).

OBJECTIVE.—

To update recent developments, in this review article, the authors wrote minireviews in the following 4 areas: lobular neoplasm, adenomyoepithelial lesions, papillary lesions, and fibroepithelial lesions.

DATA SOURCES.—

The sources include extensive literature review, personal research, and experience.

CONCLUSIONS.—

With the wide practice of screening mammography, these lesions are not uncommon in image-guided core biopsies and excisional specimens. Many recent developments have emerged in understanding these lesions. We aim to provide readers with concise updates for each of these lesions with a focus on recent updates in definitions, diagnostic criteria, management, and molecular profiles that are most relevant to the daily practice of pathology and patient management.

High-risk lesions of the breast: concurrent diagnostic tools and management recommendations

Breast lesions with uncertain malignant behavior, also known as high-risk or B3 lesions, are composed of a variety of pathologies with differing risks of associated malignancy. While open excision was previously preferred to manage all high-risk lesions, tailored management has been increasingly favored to reduce overtreatment and spare patients from unnecessary anxiety or high healthcare costs associated with surgical excision. The purpose of this work is to provide the reader with an accurate overview focused on the main high-risk lesions of the breast: atypical intraductal epithelial proliferation (atypical ductal hyperplasia), lobular neoplasia (including the subcategories lobular carcinoma in situ and atypical lobular hyperplasia), flat epithelial atypia, radial scar and papillary lesions, and phyllodes tumor. Beyond merely presenting the radiological aspects of these lesions and the recent literature, information about their potential upgrade rates is discussed in order to provide a useful guide for appropriate clinical management while avoiding the risks of unnecessary surgical intervention (overtreatment).

Management of Lobular Neoplasia Found on Core Needle Biopsy Performed for Calcifications Using Precise Radiologic-Pathologic Correlation

OBJECTIVE. The purpose of our study was to evaluate the upgrade rate of calcified lobular neoplasia (LN) versus incidental noncalcified classic LN found on core needle biopsy performed for the evaluation of suspicious calcifications. MATERIALS AND METHODS. This retrospective study included 390 consecutive image-guided breast core needle biopsies with microcalcifications as the target that were performed between December 2009 and July 2017. In 81 of the 390 core biopsies, the highest-risk lesion was LN that then underwent either excision or imaging follow-up. Core biopsy results were compared with excision and imaging follow-up findings. An upgrade of LN was defined as ductal carcinoma in situ or invasive ductal or lobular carcinoma. RESULTS. Of 81 LN diagnosed on core biopsy performed for calcifications, 16 had calcifications within the LN. Fifteen of these 16 cases underwent surgical excision, and three (3/15, 20.0%) were upgraded on excision. Of the 64 core biopsies showing incidental noncalcified LN with benign concordant entities containing calcifications, 42 underwent surgical excision, and one LN (1/42, 2.4%) was upgraded. Twenty-three total lesions (one calcified LN and 22 noncalcified LN) were followed with imaging rather than excision. No cancers were detected among the follow-up group. One case was deemed to have discordant findings on radiologic-pathologic review and was sent for excision, which showed invasive cancer with tubulolobular and lobular features. CONCLUSION. Women undergoing stereotactic core needle biopsy for calcifications revealing noncalcified incidental classic LN and a benign concordant entity that could explain the presence of the target calcifications have a low risk of upgrade and may be followed with imaging. Surgical excision should be offered to women who have LN with calcifications.

High-Risk Lesions Detected by MRI-Guided Core Biopsy: Upgrade Rates at Surgical Excision and Implications for Management

OBJECTIVE. The purpose of our study was to evaluate the upgrade rates of high-risk lesions (HRLs) diagnosed by MRI-guided core biopsy and to assess which clinical and imaging characteristics are predictive of upgrade to malignancy. MATERIALS AND METHODS. A retrospective review was performed of all women who presented to an academic breast radiology center for MRI-guided biopsy between January 1, 2015, and November 30, 2018. Histopathologic results from each biopsy were extracted. HRLs-that is, atypical ductal hyperplasia (ADH), lobular carcinoma in situ (LCIS), atypical lobular hyperplasia (ALH), radial scar, papilloma, flat epithelial atypia (FEA), benign vascular lesion (BVL), and mucocelelike lesion-were included for analysis. Clinical history, imaging characteristics, surgical outcome, and follow-up data were recorded. Radiologic-pathologic correlation was performed. RESULTS. Of 810 MRI-guided biopsies, 189 cases (23.3%) met the inclusion criteria for HRLs. Of the 189 HRLs, 30 cases were excluded for the following reasons: 15 cases were lost to follow-up, six cases were in patients who received neoadjuvant chemotherapy after biopsy, two lesions that were not excised had less than 2 years of imaging follow-up, and seven lesions had radiologic-pathologic discordance at retrospective review. Of the 159 HRLs in our study cohort, 13 (8.2%) were upgraded to carcinoma. Surgical upgrade rates were high for ADH (22.5%, 9/40) and FEA (33.3%, 1/3); moderate for LCIS (6.3%, 3/48); and low for ALH (0.0%, 0/11), radial scar (0.0%, 0/28), papilloma (0.0%, 0/26), and BVL (0.0%, 0/3). Of the upgraded lesions, 69.2% (9/13) were upgraded to ductal carcinoma in situ (DCIS) or well-differentiated carcinoma. ADH lesions were significantly more likely to be upgraded than non-ADH lesions (p = .005). CONCLUSION. ADH diagnosed by MRI-guided core biopsy warrants surgical excision. The other HRLs, however, may be candidates for imaging follow-up rather than excision, especially after meticulous radiologic-pathologic correlation.

Lobular carcinoma in situ: diagnostic criteria and molecular correlates

Lobular neoplasia (LN) is an atypical proliferation of small, dyscohesive epithelial cells within the terminal duct lobular unit (TDLU), with or without pagetoid extension and encompasses both lobular carcinoma in situ (LCIS) and atypical lobular hyperplasia (ALH). LN is a non-obligate precursor of invasive breast carcinoma and the diagnosis of LN confers an increased risk of invasive carcinoma development, compared to the general population. Diagnostic challenges arise in the accurate classification of LCIS into classic, pleomorphic and florid subtypes, in distinguishing between LCIS and ductal carcinoma in situ (DCIS) and in the appropriate use and interpretation of E-cadherin immunohistochemistry. Due to the paucity of robust data on the natural history of LCIS, and hence its clinical significance, the management is often pragmatic rather than entirely evidence-based and requires a multidisciplinary approach. In this review, we discuss the clinicopathologic and molecular features of LCIS and address the key challenges that arise in the diagnosis and management of LCIS.

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.

Lobular intraepithelial neoplasia: Outcomes and optimal management

INTRODUCTION

Lobular neoplasia is a term encompassing both atypical lobular hyperplasia and lobular carcinoma in situ. These pathological findings are of uncertain malignant potential and predispose to a higher lifetime risk of breast cancer. Debate surrounds the management of such lesions, with the rationale for diagnostic excision based on the possibility of upgrading to malignancy. In this study, we report the upgrade rate of these lesions and risk of subsequent development of breast cancer.

METHODS

This is a retrospective review of a prospectively maintained data base of all biopsies of breast screening-detected abnormalities in a single Irish breast-screening unit. We included all patients with lobular neoplasia on core needle biopsy who underwent diagnostic excision from 2005 to 2012. We excluded those who had concurrent high-risk lesions on biopsy. End points included upgrade rate and subsequent diagnosis of malignancy on follow-up.

RESULTS

During the study period, 66 patients met criteria for inclusion, with a mean age of 53.74 years. Upgrade rate following excision was 13.64% (n = 9/66). Of those not upgraded, 7.02% (n = 4/57) were subsequently diagnosed with malignancy. Median time to diagnosis was 59.61 months (range = 10.5-124.4).

CONCLUSION

There is a significant rate of upgrade following diagnostic excision of lobular neoplasia, supporting the practice of diagnostic excision. There is an increased lifetime risk of breast cancer for women with a diagnosis of lobular neoplasia, with many of these cancers occurring outside the standard five-year monitoring period, suggesting a potential benefit in extending surveillance.

Do Histopathology and Clinical Outcomes of Breast Atypia Vary by Race/Ethnicity?

BACKGROUND

The clinical behavior of breast cancer varies by racial and ethnic makeup (REM), but the impact of REM on the clinical outcomes of breast atypia remains understudied. We examined the impact of REM on risk of underlying or subsequent carcinoma following a diagnosis of breast atypia.

METHODS

In this retrospective, single-institution chart review, adult women diagnosed with breast atypia (atypical ductal hyperplasia, atypical lobular hyperplasia, or lobular carcinoma in situ) were stratified by REM. Regression modeling was used to estimate risk of underlying or subsequent carcinoma.

RESULTS

We identified 539 patients with breast atypia, including 15 Hispanic (2.8%), 127 non-Hispanic black (23.6%), and 397 non-Hispanic white women (73.7%). Diagnoses included 75.1% atypical ductal hyperplasia (n = 405), 4.6% atypical lobular hyperplasia (n = 25), and 20.2% lobular carcinoma in situ (n = 109). Rates for each type of atypia did not vary by REM (P = 0.33). Of those with atypia on needle biopsy, the rate of underlying carcinoma at excision was 17.3%. After adjustment, REM was not associated with greater risk for carcinoma at excision (P = 0.41). Of those with atypia alone on surgical excision, the rate of a subsequent carcinoma diagnosis was 15.4% (median follow-up 49 mo). REM was not associated with a long-term risk for carcinoma (P = 0.37) or differences in time to subsequent carcinoma (log-rank P = 0.52). Chemoprevention uptake rates were low (10.6%), especially among Hispanic (0%) and non-Hispanic black (3.8%) patients (P = 0.01).

CONCLUSIONS

Among patients with atypia, REM does not appear to influence type of histologic atypia, risk for carcinoma, or clinical outcome, despite differences in chemoprevention rates.

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.

Performance of a clinical and imaging-based multivariate model as decision support tool to help save unnecessary surgeries for high-risk breast lesions

PURPOSE

To investigate the performance of an imaging and biopsy parameters-based multivariate model in decreasing unnecessary surgeries for high-risk breast lesions.

METHODS

In an IRB-approved study, we retrospectively reviewed all high-risk lesions (HRL) identified at imaging-guided biopsy in our institution between July 1, 2014-July 1, 2017. Lesions were categorized high-risk-I (HR-I = atypical ductal hyperplasia, atypical lobular hyperplasia, lobular carcinoma in situ and atypical papillary lesion) and II (HR-II = Flat epithelial atypia, radial scar, benign papilloma). Patient risk factors, lesion features, detection and biopsy modality, excision and cancer upgrade rates were collected. Reference standard for upgrade was either excision or at least 2-year imaging follow-up. Multiple logistic regression analysis was performed to develop a multivariate model using HRL type, lesion and biopsy needle size for surgical cancer upgrade with performance assessed using ROC analysis.

RESULTS

Of 699 HRL in 652 patients, 525(75%) had reference standard available, and 48/525(9.1%) showed cancer at surgical excision. Excision (84.5% vs 51.1%) and upgrade (17.6%vs1.8%) rates were higher in HR-I compared to HR-II (p < 0.01). In HR-I, small needle size < 12G vs ≥ 12G [32.1% vs 13.2%, p < 0.01] and less cores [< 6 vs ≥ 6, 28.6%vs13.7%, p = 0.01] were significantly associated with higher cancer upgrades. Our multivariate model had an AUC = 0.87, saving 28.1% of benign surgeries with 100% sensitivity, based on HRL subtype, lesion size(mm, continuous), needle size (< 12G vs ≥ 12G) and biopsy modality (US vs MRI vs stereotactic) CONCLUSION: Our multivariate model using lesion size, needle size and patient age had a high diagnostic performance in decreasing unnecessary surgeries and shows promise as a decision support tool.

Risk for Upgrade to Malignancy After Breast Core Needle Biopsy Diagnosis of Lobular Neoplasia: A Systematic Review and Meta-Analysis

PURPOSE

Lobular neoplasia (LN) detected on breast core needle biopsy is frequently managed with surgical excision because of concern for undersampled malignancy. The authors performed a systematic review and meta-analysis to estimate the risk for upgrade to malignancy in the setting of imaging-concordant classic LN diagnosed on core biopsy.

METHODS

PubMed and Embase were searched for original articles published from 1998 to 2020 that reported rates of upgrade to malignancy for classic LN, including atypical lobular hyperplasia (ALH) and classic lobular carcinoma in situ (LCIS). Two reviewers extracted study data and assessed the following quality criteria: exclusion of variant LCIS, exclusion of imaging-discordant lesions, and outcome reporting for ≥70% of lesions. For studies meeting all criteria, pooled risks for upgrade to any malignancy (invasive carcinoma or ductal carcinoma in situ) and invasive malignancy for all LN, ALH, and LCIS were estimated using random-effects models.

RESULTS

For 65 full-text articles included in the review, the risk for upgrade to any malignancy ranged from 0% to 45%. Among the 16 studies that met all quality criteria for the meta-analysis, pooled risks for upgrade to any malignancy were 3.1% (95% confidence interval [CI], 1.8%-5.2%) for all LN, 2.5% (95% CI, 1.6%-3.9%) for ALH, and 5.8% (95% CI, 2.9%-11.3%) for LCIS. Risks for upgrade to invasive malignancy were 1.3% (95% CI, 0.7%-2.4%) for all LN, 0.4% (95% CI, 0.0%-4.2%) for ALH, and 3.5% (95% CI, 2.0%-5.9%) for LCIS.

CONCLUSIONS

The risk for upgrade to malignancy for LN found on breast biopsy is low. Imaging surveillance can likely be offered as an alternative to surgical management for LN, particularly for ALH.

Upgrade at excisional biopsy after a core needle biopsy diagnosis of classic lobular carcinoma in situ

BACKGROUND

Management of patients with classic lobular carcinoma in situ diagnosed on core needle biopsy remains controversial, in part because of clinicopathologic overlap with atypical lobular hyperplasia. Although atypical lobular hyperplasia on core needle biopsy is observed because of its low upgrade rate (~1%), consensus is lacking for lobular carcinoma in situ. Therefore, we evaluated lobular carcinoma in situ upgrade rates.

METHODS

With institutional review board approval, we identified 90 patients (from October 2008 to December 2019) with lobular carcinoma in situ on core needle biopsy as their highest-risk lesion. We excluded patients with concurrent ipsilateral cancer. Variables associated with upgrade were assessed with logistic regression.

RESULTS

Of the 90 patients, 81 (90%), median age 55 y, underwent surgical excision. Indications for diagnostic core needle biopsy included mammographic calcifications (48, 53.3%), mass/distortion (28, 31.1%), and non-mass enhancement (12, 13.3%). Final surgical pathology upgraded 11 of 81 patients (13.6%, 95% CI: 7.8%-22.7%) to cancer: invasive lobular (n = 7), invasive ductal (n = 1), and ductal carcinoma in situ/pleomorphic lobular carcinoma in situ (n = 3). Only 1 patient with invasive cancer was node-positive. Concurrent contralateral cancer (OR 4.41, 95% CI: 1.06-17.38, P = .04) and larger lesion size (OR 1.78 per 1 cm, 95% CI: 1.19-2.95, P = .005) predicted upgrade.

CONCLUSION

Our data suggest that, unlike atypical lobular hyperplasia, lobular carcinoma in situ identified on core needle biopsy should be surgically excised. The high proportion of upgrades to early stage invasive lobular carcinoma underscores the value of this approach.

When to do surgical resection for atypical breast lesions: Results of a prospective cohort of 518 lesions

AIM

There is no consensual indication for surgical resection after diagnosis on per-cutaneous biopsy of borderline breast lesions (B3). We evaluate under-evaluation rate of per-cutaneous biopsy and predictive factors of under-evaluation. We analyze accuracy of reported decision-making tools.

METHODS

We conduct a prospective multicentric study including, atypic-ductal hyperplasia (ADH), atypic-lobular hyperplasia (ALH), atypic-cylindro-cubic metaplasia (FEA), papilloma, radial scars (RS) and phyllod tumors. When several B3 lesions were associated, the more severe lesion was used to classify the lesion. We determined breast cancers (BC) rate and histologic type. Among 478 patients, 518 B3 lesions were studied: 15.1% (78) FEA, 48.6% (252) ADH, 16.8% (n = 87) ALH, 5.4% (n = 28) RS, 12% (n = 62) papilloma, 0.8% (n = 4) phyllod tumors and 0,8% (n = 4) with a suspicious low grade DCIS. More than 1 lesion was identified in 31.9% (165) of cases. A surgical resection was performed for 86.3% (447/518) lesions. Significant factors of surgical resection were: residual micro-calcification after biopsy (OR: 2.7) and type of B3 lesion.

RESULTS

Overall BC rate was 15.3% (68/445) with 79.4% (54) in-situ carcinomas. According to B3 lesions, BC rates were 12.9% for FEA, 20% for ADH, 11.6% for ALH, 3.7% for RS, 8.8% for papilloma and 25% for suspicious in-situ carcinoma. A score has been calculated and patients were distributed in 3 groups. Patient's rates without BC were respectively: 100%, 80.4% and 80.6% (p = 0.029).

CONCLUSION

In conclusion, it could be suggested to avoided complementary surgical resection in case of good radio-pathologic concordance and low probability of BC.

Atypical Ductal Hyperplasia and Lobular Neoplasia: Update and Easing of Guidelines

OBJECTIVE. Atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), and lobular carcinoma in situ (LCIS) are among high-risk lesions that have been previously recommended for surgical excision when diagnosed on core needle biopsy. Recent studies have examined whether imaging surveillance is a reasonable alternative to surgical management for these lesions. This article synthesizes the evidence regarding management of atypical hyperplasia and LCIS diagnosed on core needle biopsy and clinical implications of these diagnoses on future breast cancer risk as well as highlights areas of further research needed to improve practice guidelines for these high-risk lesions. CONCLUSION. Although surgical excision is still recommended after diagnosis of ADH on core needle biopsy, in specific circumstances ALH and LCIS can safely be managed by imaging surveillance.

Outcomes of classic lobular neoplasia diagnosed on breast core needle biopsy: a retrospective multi-center study

Management of classic lobular neoplasia (cLN) diagnosed on core needle biopsy (CNB) is controversial. Our aim in this study was to review cases of cLN diagnosed on CNB to determine the rate and risk factors of an upgrade to ductal carcinoma in situ (DCIS) or invasive carcinoma on excision. All breast CNBs with a diagnosis of atypical lobular hyperplasia (ALH) or classic lobular carcinoma in situ (cLCIS) from three different institutions within a single health care system between 2013 and 2018 were retrieved. Cases with any additional high-risk lesions in the same CNB or discordant radiological-pathological correlation were excluded. Information about age, personal history of prior or concurrent breast cancer (P/CBC), and radiological and histological findings were recorded. A total of 287 cLN cases underwent surgical excision. Analysis of these 287 cLN cases showed 11 (3.8%) upgrade lesions on excision. Among the 172 ALH cases, there were 3 (1.7%) upgrades, which were all invasive lobular carcinomas (ILCs). On the other hand, 8 of 115 (7%) cLCIS cases revealed upgrade on excision (2 ILC, 5 DCIS. and 1 ILC + DCIS). Statistical analysis revealed that cLN cases with P/CBC, radiological asymmetry, or architectural distortion had a statistically significant higher upgrade rate on excision. Our findings revealed a low upgrade rate (3.8%) on the excision of classic lobular neoplasia diagnosed on breast core needle biopsy. Clinicoradiological surveillance can be appropriate when lobular neoplasia is identified on core biopsy with pathological radiological concordance in patients without a history of breast cancer, with the caveat that radiological asymmetry and architectural distortion are associated with a significant increase in an upgrade on excision.

The Influence of Age on the Histopathology and Prognosis of Atypical Breast Lesions

BACKGROUND

Although several prognostic variables and risk factors for breast cancer are age-related, the association between age and risk of cancer with breast atypia is controversial. This study aimed to compare the type of breast atypia and risk of underlying or subsequent breast cancer by age.

METHODS

Adult women with breast atypia (atypical ductal hyperplasia, atypical lobular hyperplasia, and lobular carcinoma in situ) at a single institution from 2008 to 2017 were stratified by age at initial diagnosis: <50 y, 50-70 y, and >70 y. Regression modeling was used to estimate the association of age with risk of underlying carcinoma or subsequent cancer diagnosis.

RESULTS

A total of 530 patients with atypia were identified: 31.1% < 50 y (n = 165), 58.1% 50-70 y (n = 308), and 10.8% > 70 y (n = 57). The proportion of women with atypical ductal hyperplasia steadily increased with age, compared with atypical lobular proliferations (P = 0.04). Of those with atypia on needle biopsy, the overall rate of underlying carcinoma was 17.5%. After adjustment, older age was associated with a greater risk of underlying carcinoma (odds ratio: 1.028, 95% confidence interval: 1.003-1.053; P = 0.03). Of those confirmed to have atypia on surgical excision, the overall rate of a subsequent cancer diagnosis was 15.7%. Age was not associated with a long-term risk for breast cancer (P = 0.48) or the time to a subsequent diagnosis of carcinoma (log-rank P = 0.41).

CONCLUSIONS

Although atypia diagnosed on needle biopsy may be sufficient to warrant surgical excision, older women may be at a greater risk for an underlying carcinoma, albeit the long-term risk for malignancy associated with atypia does not appear to be affected by age.

Triaging Atypical Lobular Hyperplasia and Lobular Carcinoma In Situ on Percutaneous Core Biopsy to Surgery or Observation: Assiduous Radiologic-Pathologic Correlation Works, Quantitating Extent of Disease Does Not

Context.—

The management of lobular neoplasia (LN) found on core biopsy is controversial and ranges from obligatory surgical excision to clinical/imaging observation.

Objective.—

To determine if in cases of core needle biopsy yielding LN, quantification of normal and diseased terminal ductal lobular units (TDLUs) can predict which cases require surgical excision and which can be safely followed. A secondary goal is to assess whether the concordance or discordance of core biopsy results, determined by rigorous radiologic-pathologic correlation, can predict for upgrade to malignancy at excision.

Design.—

In this retrospective study, 79 specimens from 78 women who underwent image-guided core needle biopsies between 2005 and 2012 yielding LN were evaluated for total number of TDLUs and total number and percentage of TDLUs involved by LN. Additionally, radiologic-pathologic correlation was performed to assess concordance or discordance. All were correlated with the results of surgical excisional biopsy or imaging/clinical follow-up.

Results.—

There were 5 upgrades to malignancy. There was no association between upgrade to malignancy and any of the 3 TDLU variables evaluated, including total TDLUs in the specimen (P = .42), total abnormal TDLUs (P = .56), and percent of TDLUs that are abnormal (P = .07). Kendall rank correlation demonstrated a correlation between discordance and upgrade to cancer at surgery that was statistically significant (τb = −0.394, P &lt; .001).

Conclusions.—

Quantifying total TDLU and those involved by LN on core biopsy will not aid in triaging patients to surgery or observation. Assiduous radiologic-pathologic correlation to determine lesion concordance/discordance can predict those patients who would benefit from surgical excision.

Lesions of "uncertain malignant potential" in the breast (B3) identified with mammography screening

Background

Core needle biopsy (CNB) is a standard diagnostic procedure in the setting of breast cancer screening. However, CNB may result in the borderline diagnoses of lesion of uncertain malignant potential (B3). The aim of this study was to access the outcome of lesions diagnosed as B3 category in a large series of screen-detected cases to evaluate the rates of malignancy for the different histological subtypes.

Methods

We identified all CNBs over a six-year period (2009-2015) in a breast cancer screening unit in Germany. A total of 8.388 CNB’s were performed for screen detected breast lesions. B3 diagnosis comprised 4.5% (376/8.388). Of the 376 patients who were diagnosed as B3, 299 underwent subsequent excision biopsy with final excision histology.

Results

Out of 376 patients diagnosed with B3 lesions, the prevalence of different histopathology showed 161 (42.8%) patients with atypical ductal hyperplasia (ADH), 98 (26.1%) with flat epithelial atypia (FEA), 50 women (13.3%) showed lobular neoplasia (LN), in 40 (10.6%) patients papillary findings and in 27 patients (7.2%) a radial scar complex. Final excision histology was benign in 74% (221/299) and malignant in 26% (78/299) of the patients. Lesion specific positive predictive values (PPV) for a subsequent diagnosis of in situ or invasive carcinoma were as follows: ADH 40%, FEA 20.5%, papillary lesion 13.5%, radial scar 16.6%, LN 0%.

Conclusion

Our results show that approximately one-third of core needle biopsies of screen detected breast lesions classified as B3 are premalignant or malignant on excision.

Lesions of uncertain malignant potential of the breast (B3) are heterogeneous in respect to risk of malignancy.

When Does Atypical Ductal Hyperplasia Require Surgical Excision?

Atypical ductal hyperplasia (ADH) is a proliferative, nonobligate precursor breast lesion and a marker of increased risk for breast carcinoma. Surgical excision remains the standard recommendation following a core needle biopsy result consistent with ADH. Recent research suggests that women with no mass lesion or discordance, removal of greater than or equal to 90% of calcifications at the time of core needle biopsy, involvement of less than or equal to 2 terminal duct lobular units, and absence of cytologic atypia or necrosis are likely to have a less than 5% chance of a missed cancer.

Core Needle Biopsy of the Breast: An Evaluation of Contemporary Data

Benign and atypical lesions associated with breast cancer risk are often encountered in core needle biopsies (CNBs) of the breast. For these lesions, the rate of "upgrade" to carcinoma in excision specimens varies widely in the literature. Many CNB studies are limited by a lack of radiological-pathological correlation, consistent criteria for excision, and clinical follow-up for patients who forego excision. This article highlights contemporary diagnostic criteria and outcome data that would support an evidence-based approach to the management of these nonmalignant lesions of the breast diagnosed on CNB.

Observation versus excision of lobular neoplasia on core needle biopsy of the breast

PURPOSE

Controversy surrounds management of lobular neoplasia (LN), [atypical lobular hyperplasia (ALH) or lobular carcinoma in situ (LCIS)], diagnosed on core needle biopsy (CNB). Retrospective series of pure ALH and LCIS reported "upgrade" rate to DCIS or invasive cancer in 0-40%. Few reports document radiologic/pathologic correlation to exclude cases of discordance that are the likely source of most upgrades, and there is minimal data on outcomes with follow-up imaging and clinical surveillance.

METHODS

Cases of LN alone on CNB (2001-2014) were reviewed. CNB yielding LN with other pathologic findings for which surgery was indicated were excluded. All patients had either surgical excision or clinical follow-up with breast imaging. All cases included were subject to radiologic-pathologic correlation after biopsy.

RESULTS

178 cases were identified out of 62213 (0.3%). 115 (65%) patients underwent surgery, and 54 (30%) patients had surveillance for > 12 months (mean = 55 months). Of the patients who underwent surgical excision, 13/115 (11%) were malignant. Eight of these 13 found malignancy at excision when CNB results were considered discordant (5 DCIS, and 3 invasive lobular carcinoma), with the remainder, 5/115 (4%), having a true pathologic upgrade: 3 DCIS, and 2 microinvasive lobular carcinoma. Among 54 patients not having excision, 12/54 (22%) underwent subsequent CNB with only 1 carcinoma found at the initial biopsy site.

CONCLUSIONS

Surgical excision of LN yields a low upgrade rate when careful consideration is given to radiologic/pathologic correlation to exclude cases of discordance. Observation with interval breast imaging is a reasonable alternative for most cases.

Lobular Carcinoma In Situ

Lobular carcinoma in situ (LCIS) is a risk factor and a nonobligate precursor of breast carcinoma. The relative risk of invasive carcinoma after classic LCIS diagnosis is approximately 9 to 10 times that of the general population. Classic LCIS diagnosed on core biopsy with concordant imaging and pathologic findings does not mandate surgical excision, and margin status is not reported. The identification of variant LCIS in a needle core biopsy specimen mandates surgical excision, regardless of radiologic-pathologic concordance. The presence of variant LCIS close to the surgical margin of a resection specimen is reported, and reexcision should be considered.

Current Concepts in Diagnosis, Molecular Features, and Management of Lobular Carcinoma In Situ of the Breast With a Discussion of Morphologic Variants

Context.—

Lobular carcinoma in situ (LCIS) refers to a neoplastic proliferation of cells that characteristically shows loss of E-cadherin expression and has long been regarded as a risk factor for invasive breast cancer. Long-term outcome studies and molecular data have also implicated LCIS as a nonobligate precursor to invasive carcinoma. In the past few decades, pleomorphic and florid LCIS have been recognized as morphologic variants of LCIS with more-aggressive histopathologic features, less-favorable biomarker profiles, and more-complex molecular features compared with classic LCIS. There is still a lack of consensus regarding certain aspects of managing patients with LCIS.

Objectives.—

To review recently published literature on LCIS and to provide an overview of the current morphologic classification of LCIS, recent molecular advances, and trends in patient management.

Data Sources.—

Sources included peer-reviewed, published journal articles in PubMed (US National Library of Medicine, Bethesda, Maryland) and published guidelines from the National Comprehensive Cancer Network (Fort Washington, Pennsylvania).

Conclusions.—

Lobular carcinoma in situ represents a marker for increased risk of breast cancer, as well as a nonobligate precursor to invasive carcinoma. Morphologic variants of LCIS—florid and pleomorphic LCIS—are genetically more-complex lesions and are more likely to be associated with invasive carcinoma. Further investigation into which molecular alterations in LCIS are associated with progression to invasive carcinoma is needed to help guide medical and surgical management.

Treatment and survival outcomes of lobular carcinoma in situ of the breast: a SEER population based study

Lobular carcinoma in situ (LCIS) represents 5.3% of in situ specimens, and is thought to carry a low risk for developing to the invasive lobular breast cancer (ILC). There is still no standard care approach for patients with LCIS. We aimed to define the impacts of surgical and radiation intervention on survival outcomes of LCIS. LCIS cases from 2004 to 2013 of the recent Surveillance, Epidemiology, and End Results (SEER) database were analyzed. Clinicopathologic features were analyzed in 16002 patients between 2004 and 2013. Treatment modalities included no surgery (NS), lumpectomy alone (LA), lumpectomy with radiation treatment (LRT), mastectomy alone (MA) and mastectomy with radiation treatment (MRT). The overall survival (OS) was calculated by the Kaplan-Meier method. Univariate and multivariate analyses were performed using the variables of treatment, race, hormone receptor status, grade and age. Among 16002 patients, median follow-up was 54 months. Patients treated with LA had superior OS for NS (P = 0.001), MA (P < 0.001) and MRT P = 0.018). LRT only had superior OS for MRT (P = 0.009). There was no statistically significance between LA and LRT (P = 0.317). Improved OS was also correlated with younger age (P < 0.001), progesterone receptor positive (P = 0.001). Black patients had the worst OS (P < 0.001). There was no obvious survival difference among grade groups (P = 0.536). The LCIS patients treated with LA or LRT had better survival comparing with other groups. Considering the medical expense and the risk of radiotherapy, LA may be the most appropriate therapy for patients with LCIS.

Pathologic High-risk Lesions, Diagnosis and Management

Percutaneous imaging-guided core needle biopsy (CNB) is a less invasive and less expensive alternative to surgical biopsy for the evaluation of breast lesions. After a CNB the radiologist determine if there is concordance between the pathology, imaging, and clinical findings. Patient management after CNB diagnosis of high-risk breast lesion varies. Surgical excision is warranted for lesions yielding a CNB diagnosis of ADH; however controversy exists regarding the need for surgical excision after CNB diagnosis of radial scar, papillary lesion, atypical lobular hyperplasia (ALH), or lobular carcinoma in situ (LCIS). Repeat CNB or surgical excision is warranted if histologic findings and imaging findings are discordant.

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

OBJECTIVES

Flat epithelial atypia (FEA) is a relatively new diagnostic term with uncertain clinical significance for surgical management. Any implied risk of invasive breast cancer associated with FEA is contingent upon diagnostic reproducibility, yet little is known regarding its use.

MATERIALS AND METHODS

Pathologists in the Breast Pathology Study interpreted one of four 60-case test sets, one slide per case, constructed from 240 breast biopsy specimens. An electronic data form with standardized diagnostic categories was used; participants were instructed to indicate all diagnoses present. We assessed participants' use of FEA as a diagnostic term within: 1) each test set; 2) 72 cases classified by reference as benign without FEA; and 3) six cases classified by reference as FEA. 115 pathologists participated, providing 6900 total independent assessments.

RESULTS

Notation of FEA ranged from 0% to 35% of the cases interpreted, with most pathologists noting FEA on 4 or more test cases. At least one participant noted FEA in 34 of the 72 benign non-FEA cases. For the 6 reference FEA cases, participant agreement with the case reference FEA diagnosis ranged from 17% to 52%; diagnoses noted by participating pathologists for these FEA cases included columnar cell hyperplasia, usual ductal hyperplasia, atypical lobular hyperplasia, and atypical ductal hyperplasia.

CONCLUSIONS

We observed wide variation in the diagnosis of FEA among U.S. pathologists. This suggests that perceptions of diagnostic criteria and any implied risk associated with FEA may also vary. Surgical excision following a core biopsy diagnosis of FEA should be reconsidered and studied further.

Population-Based Analysis of Breast Cancer Incidence and Survival Outcomes in Women Diagnosed with Lobular Carcinoma In Situ

PURPOSE

A diagnosis of lobular carcinoma in situ (LCIS) is associated with an increased risk of developing breast cancer, although little data exist on long-term patient outcomes, including those who develop subsequent breast malignancies.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify women with a histological diagnosis of LCIS between 1983 and 2014. The incidence and clinicopathologic features of subsequent malignancies were then examined, and the Kaplan-Meier method and multivariable Cox PH regression used to obtain breast cancer-specific survival (BCSS) estimates and associated hazard ratios.

RESULTS

Overall, 19,462 women swith a mean age at LCIS diagnosis of 53.7 years, and a 10- and 20-year cumulative incidence of subsequent breast malignancy of 11.3% [95% confidence interval (CI) 10.7-11.9%] and 19.8% (95% CI 18.8-20.9) met the eligibility criteria. At a median follow-up of 8.1 years (range 0-30.9) a total of 1837 primary breast cancers were diagnosed, of which 55.2% were diagnosed in the ipsilateral breast. Most breast cancers were of low/intermediate grade, hormone receptor-positive, and diagnosed in early stages. Of subsequent malignancies, invasive ductal carcinoma (IDC) distributed equally across both breasts, whereas invasive lobular carcinoma (ILC) was more likely to present in the ipsilateral breast (69.0% ILC vs. 49.2% IDC; p < 0.001). On multivariable analysis, type of surgical treatment for LCIS had no affect on long-term survival (p = 0.44). The 10- and 20-year BCSS for women with LCIS was 98.9 and 96.3%, respectively.

CONCLUSION

Women with LCIS who are diagnosed with a subsequent primary breast cancer are often diagnosed in early stages and have excellent BCSS.

Lobular carcinoma in situ of the breast - correlation between minimally invasive biopsy and final pathology

INTRODUCTION

Lobular carcinoma in situ (LCIS) is regarded as a non-obligate precursor of invasive breast cancer (IBC). Hence, the optimal management of LCIS found on minimally invasive breast biopsy remains a subject of debate. The aim of this study was to evaluate the correlation of biopsy findings with postoperative histology and to identify risk factors for upstaging to IBC.

MATERIAL AND METHODS

Twenty-seven patients with pure LCIS diagnosed on image-guided biopsy (vacuum-assisted or core-needle) underwent subsequent surgery. Clinical, radiological and histological features were compared to the final pathology after surgical excision.

RESULTS

Median age of patients was 56 years while median size of LCIS was 15 mm. Final examination demonstrated IBC foci in 29.6% of lesions. Upstaged patients were younger and had larger lesions but without statistical significance (p = 0.07 and p = 0.09, respectively). Palpable tumours (p = 0.0004), BIRADS 5 lesions (p = 0.0001), masses (p = 0.016) and pleomorphic LCIS (p = 0.0001) had a significantly increased rate of upstaging. Guidance of the procedure (ultrasound vs. stereotactic) was significantly associated with the upstaging risk (p = 0.016), while the importance of the biopsy technique (core-needle vs. vacuum-assisted) was not confirmed (p = 0.37). After excluding pleomorphic LCIS and mass-forming classic LCIS, there was no risk of upstaging for lesions with BIRADS 4 mammographic abnormalities.

CONCLUSIONS

Pleomorphic histology, mass formation and BIRADS 5 category reflect more aggressive behaviour of LCIS and identify patients who need subsequent surgery. For other patients, close follow-up could be a safe alternative.

Sonographic Appearance of Lesions Diagnosed as Lobular Neoplasia at Sonographically Guided Biopsies

OBJECTIVE

The objective of our study was to review the sonographic features of breast lesions yielding lobular neoplasia (LN) at sonographically guided biopsy, evaluate the surgical pathology outcome of these lesions, and determine if imaging findings or clinical features can be used to predict an upgrade to malignancy.

MATERIALS AND METHODS

Of the 8205 sonographically guided breast biopsies (14-gauge cores) performed from 2007 through 2014, 22 yielded a diagnosis of LN, which means that LN was the most severe pathologic lesion. Imaging features were analyzed in consensus by two radiologists. Correlation of biopsy findings with definitive pathologic results was performed when available.

RESULTS

Twenty-two LN lesions (20 patients [mean age ± SD, 52.05 ± 13.66 years]) were diagnosed at biopsy. Of the LN lesions that were seen on mammography (6/22, 27.3%), most lesions appeared as masses (3/6, 50%). On sonography, LN lesions (mean size, 8.10 mm) appeared as masses (15/22, 68.2%) with oval shape (10/15, 66.7%), well-circumscribed or microlobulated margins (11/15, 73.3%), hypoechoic echotexture (10/15, 66.7%), posterior enhancement (73.3%, 11/15), and parallel orientation (8/15, 53.3%). Most of the masses were categorized as BI-RADS category 4 (21/22, 95.5%). Seven lesions (7/22, 31.8%) appeared as areas of shadowing or distortion without discrete masses. Twenty (20/22, 90.9%) lesions were excised surgically, and pathology results led to an upgrade in five lesions (5/20, 25% [one nonmass lesion and four masses]). Neither mammographic nor sonographic features were associated with malignant outcome (p > 0.05).

CONCLUSION

LN diagnosed at sonographically guided 14-gauge core needle biopsy does not show any specific features according to the BI-RADS lexicon and is associated with a 25% underestimation rate. No clinical or imaging characteristic is predictive of malignancy.

Contemporary indications for diagnostic open biopsy in women assessed for screen-detected breast lesions: A ten-year, single institution series of 814 consecutive cases

PURPOSE

In contemporary practice, 5% of women with non-malignant needle biopsies of screen-detected lesions still require diagnostic open biopsy (OBx). Our aims are to (i) capture a snapshot of the contemporary indications for OBx in screen-detected lesions; (ii) determine upgrade rates to malignancy (DCIS or invasive cancer); (iii) identify indications with sufficiently low upgrades to justify avoidance of OBx and (iv) propose plausible non-surgical alternatives.

METHODS

Between Jan 2005 and Dec 2014, women assessed for a screen-detected lesion and recommended for OBx are included. We retrieved patient, imaging, biopsy and final pathology or follow-up data.

RESULTS

814 lesions, mean diameter 16.7 mm, microcalcifications in 353 (43.4%) cases, lesions other than calcifications in 461 (56.6%), mean patient age 58.4 yrs, are included. Surgery was performed in 98.2% cases. Imaging follow-up (1-6.5 yrs) is available in 13 of 15 remaining cases. 27 indications for OBx were identified, with a prevalence of 0.3-13.9%. Borderline lesions (BL) comprised 64% of OBx indications, amongst which atypical ductal hyperplasia was the most prevalent at 13.9%, followed by papillary lesions, radial scars, flat epithelial atypia and lobular neoplasia. Imaging factors contributed 26.3% of OBx. In 9.8% of cases, NCB was not performed due to client, technical or cytologic factors. Overall, 261(32.1%) lesions were malignant at OBx. Upgrade rates varied from 0 to 100%, depending on the specific indication for OBx.

CONCLUSIONS

Surgical biopsy remains a valuable method of last resort for breast cancer diagnosis but strategies to limit benign breast surgery merit attention as a public health issue.

Paradigm Shifts in Breast Care Delivery: Impact of Imaging in a Multidisciplinary Environment

OBJECTIVE

The practice of breast imaging in a collaborative multidisciplinary environment adds significant value to outcomes in women's health care. In this article, we describe multidisciplinary considerations in breast cancer screening and early detection, the impact of imaging and histopathologic findings in the diagnostic evaluation and management of breast abnormalities, and the contribution of imaging to surgical and radiation therapy planning for the breast cancer patient.

CONCLUSION

The multidisciplinary delivery of breast care for women that incorporates screening, diagnosis of borderline and high-risk lesions, and management of the breast cancer patient adds considerable value to outcomes in health care.

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.