Management of lobular carcinoma in-situ and atypical lobular hyperplasia of the breast--a review

Atypical Ductal Hyperplasia and Lobular In Situ Neoplasm: High-Risk Lesions Challenging Breast Cancer Prevention

This retrospective study investigates the histopathological outcomes, upgrade rates, and disease-free survival (DFS) of high-risk breast lesions, including atypical ductal hyperplasia (ADH or DIN1b) and lobular in situ neoplasms (LIN), following Vacuum-Assisted Breast Biopsy (VABB) and surgical excision. The study addresses the challenge posed by these lesions due to their association with synchronous or adjacent Breast Cancer (BC) and increased future BC risk. The research, comprising 320 patients who underwent stereotactic VABB, focuses on 246 individuals with a diagnosis of ADH (120) or LIN (126) observed at follow-up. Pathological assessments, categorized by the UK B-coding system, were conducted, and biopsy samples were compared with corresponding excision specimens to determine upgrade rates for in situ or invasive carcinoma. Surgical excision was consistently performed for diagnosed ADH or LIN. Finally, patient follow-ups were assessed and compared between LIN and ADH groups to identify recurrence signs, defined as histologically confirmed breast lesions on either the same or opposite side. The results reveal that 176 (71.5%) patients showed no upgrade post-surgery, with ADH exhibiting a higher upgrade rate to in situ pathology than LIN1 (Atypical Lobular Hyperplasia, ALH)/LIN2 (Low-Grade Lobular in situ Carcinoma, LCIS) (38% vs. 20%, respectively, p-value = 0.002). Considering only patients without upgrade, DFS at 10 years was 77%, 64%, and 72% for ADH, LIN1, and LIN2 patients, respectively (p-value = 0.92). The study underscores the importance of a multidisciplinary approach, recognizing the evolving role of VABB. It emphasizes the need for careful follow-up, particularly for lobular lesions, offering valuable insights for clinicians navigating the complex landscape of high-risk breast lesions. The findings advocate for heightened awareness and vigilance in managing these lesions, contributing to the ongoing refinement of clinical strategies in BC care.

Upgrade rate to malignancy of uncertain malignant potential breast lesions (B3 lesions) diagnosed on vacuum-assisted biopsy (VAB) in screen detected microcalcifications: Analysis of 366 cases from a single institution

PURPOSE

We retrospectively investigated clinical, radiological, and pathological features of B3 lesions associated with the risk of subsequent upgrade to malignancy.

METHODS

We included consecutive vacuum-assisted biopsies (VABs) performed during 2011-2020 on suspicious microcalcifications not associated with other radiological signs diagnosed as B3 lesions and followed by surgical excision (SE) with definitive histological examination. Multiple logistic regression models were fitted to identify independent predictors of malignancy.

RESULTS

Out of the 366 B3 lesions included, 56 (15.3 %, 95 % CI 11.8-19.4 %) had upgraded to malignancy at SE: of these, 42/366 (11.5 %, 95 % CI 8.4-15.2 %) and 14/366 (3.8 %, 95 % CI 2.1-6.3 %) were in situ and invasive carcinoma, respectively. At univariate analysis, variables positively associated with upgrade to malignancy were age ≥ 60 years (p = 0.008), mixed morphology (p = 0.018), scattered distribution (p = 0,001), extension of microcalcifications > 10 mm (p = 0.001), and mixed B3 lesion (p = 0.017). Among B3 subtypes, the highest rates of upgrade were observed for AIDEP, LCIS/LIN2, FEA + AIDEP, FEA + LCIS/LIN2, and FEA + AIDEP + LCIS/LIN2 (24.6 %, 21.4 %, 25.3 %, 20.0 % and 40.0 % respectively), while FEA and ALH/LIN1 had a lower rates of upgrade (7.5 % and 3.7 %, respectively). Multiple logistic regression analysis confirmed as risk factors older age (p = 0.029), larger extension (p = 0.001) and mixed morphology (p = 0.007) of microcalcifications, AIDEP (p = 0.011) among pure B3 lesions, and FEA + AIDEP (p = 0.001) and FEA + AIDEP + LCIS/LIN2 (p = 0.037) among mixed B3 lesions.

CONCLUSIONS

Based on our findings, vacuum-assisted excision is reasonable as definitive management for FEA and ALH/LIN1, while SE should remain the mainstay of treatment for AIDEP and LCIS/LIN2, whose upgrade rates are too high to safely recommend VAE.

European guidelines for the diagnosis, treatment and follow-up of breast lesions with uncertain malignant potential (B3 lesions) developed jointly by EUSOMA, EUSOBI, ESP (BWG) and ESSO

INTRODUCTION

Breast lesions of uncertain malignant potential (B3) include atypical ductal and lobular hyperplasias, lobular carcinoma in situ, flat epithelial atypia, papillary lesions, radial scars and fibroepithelial lesions as well as other rare miscellaneous lesions. They are challenging to categorise histologically, requiring specialist training and multidisciplinary input. They may coexist with in situ or invasive breast cancer (BC) and increase the risk of subsequent BC development. Management should focus on adequate classification and management whilst avoiding overtreatment. The aim of these guidelines is to provide updated information regarding the diagnosis and management of B3 lesions, according to updated literature review evidence.

METHODS

These guidelines provide practical recommendations which can be applied in clinical practice which include recommendation grade and level of evidence. All sections were written according to an updated literature review and discussed at a consensus meeting. Critical appraisal by the expert writing committee adhered to the 23 items in the international Appraisal of Guidelines, Research and Evaluation (AGREE) tool.

RESULTS

Recommendations for further management after core-needle biopsy (CNB) or vacuum-assisted biopsy (VAB) diagnosis of a B3 lesion reported in this guideline, vary depending on the presence of atypia, size of lesion, sampling size, and patient preferences. After CNB or VAB, the option of vacuum-assisted excision or surgical excision should be evaluated by a multidisciplinary team and shared decision-making with the patient is crucial for personalizing further treatment. De-escalation of surgical intervention for B3 breast lesions is ongoing, and the inclusion of vacuum-assisted excision (VAE) will decrease the need for surgical intervention in further approaches. Communication with patients may be different according to histological diagnosis, presence or absence of atypia, or risk of upgrade due to discordant imaging. Written information resources to help patients understand these issues alongside with verbal communication is recommended. Lifestyle interventions have a significant impact on BC incidence so lifestyle interventions need to be suggested to women at increased BC risk as a result of a diagnosis of a B3 lesion.

CONCLUSIONS

These guidelines provide a state-of-the-art overview of the diagnosis, management and prognosis of B3 lesions in modern multidisciplinary breast practice.

Update on Lobular Neoplasia

Lobular neoplasia (LN) is a histopathologic entity that encompasses both lobular carcinoma in situ (LCIS) and atypical lobular hyperplasia (ALH). Management of LN is known to be variable and institutionally dependent. The variability in approach after a diagnosis of LN at percutaneous breast biopsy derives in part from heterogeneity in the literature, resulting in a range of reported upgrade rates to malignancy after initial identification at percutaneous biopsy, and also from historical shifts in understanding of the natural history of LN. It has become increasingly recognized that not all LN is the same and that distinct variants of LN such as pleomorphic LCIS and florid LCIS have distinct natural histories and distinct likelihoods of upgrade to malignancy. In addition, it is also increasingly understood that appropriate management of LN relies on scrupulous radiologic-pathologic correlation. This review details the imaging features and histopathologic nature of ALH, classic-type LCIS, and the LCIS variants; addresses changes in the historical understanding of this entity contributing to confusion regarding its management; and discusses the importance of performing radiologic-pathologic correlation after percutaneous biopsy to help guide appropriate management steps when LN is encountered. In addition to the short-term implications of an LN diagnosis in terms of upgrade and surgical outcomes, the long-term implications of an LN diagnosis regarding risk of developing a later breast cancer are examined. ©RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

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.

Indeterminate (B3) Breast Lesions and the Ongoing Role of Diagnostic Open Biopsy

Introduction

Due to their uncertain malignant potential, indeterminate breast lesions on core needle biopsy (CNB) require diagnostic open biopsy (DOB). This study evaluated DOB results given largely benign pathology. Lesions included are atypical papilloma, atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), and radial scar/complex sclerosing lesions (RS/CSL). Methodology. A retrospective audit from 2010 to 2017 analysed patients with a screen-detected suspicious lesion and indeterminate (B3) CNB diagnosis. Primary outcome was the malignancy upgrade rate, with secondary evaluation of patient factors predictive of malignancy including age, symptoms, mammogram characteristics, lesion size, biopsy method, and past and family history.

Results

152 patients (median age 57 years) were included, with atypical papillomas being the largest subgroup (44.7%). On DOB histology, 99.34% were benign, resulting in a 0.66% malignancy upgrade rate. Patient characteristic analysis identified 86.84% of B3 lesions were in patients greater than 50 years old. 90.13% were asymptomatic, whilst 98.68% and 72.37% had a negative past and family history. Majority 46.71% of lesions had the mammogram characteristic of being a mass. However, with 57.89% of the lesion imaging size less than 4 mm, a corresponding 60.5% of core needle biopsies were performed stereotactically. The small malignant subgroup limited predictive factor evaluation.

Conclusion

Albeit a low 0.66% malignancy upgrade rate in B3 lesions, no statistically significant patient predictive factors were identified. Until predictive factors and further assessment of vacuum-assisted excision (VAE) techniques evolve, DOB remains the standard of care.

Trends in incidence, treatment, survival and subsequent breast cancer in lobular carcinoma in situ in the Netherlands: A population-based analysis

Purpose

We analysed incidence, treatment, survival, occurrence of ductal carcinoma in situ (DCIS) and invasive breast cancer (IBC) after lobular carcinoma in situ (LCIS) in the Netherlands.

Methods

All women diagnosed with classic LCIS between 1989 and 2017 were identified from the Netherlands Cancer Registry. We calculated overall (OS), relative survival (RS) and cumulative incidence functions (CIF, accounting for competing risks) of mortality, DCIS and IBC. For IBC, standardised incidence ratios (SIR) of IBC were calculated. Analyses were stratified for surgical treatment.

Results

We included 1890 patients. Median age was 51 years. Median follow-up was 8.5 years. In 1989–2017, LCIS incidence increased from 41 to 124, surgical treatment decreased from 100% to 41.1 % – mostly BCS. 10-year OS and 20-year RS exceeded 90 % in all subgroups. Overall, 48 (2.5 %) and 270 (14.3 %) patients were diagnosed with DCIS and IBC. IBCs were mostly early-stage. After mastectomy, 13 of 14 IBCs presented contralaterally. In the other groups, 64.8–70.9 % of IBCs presented ipsilaterally, 34.5–53.9 % of these were lobular. The SIR of ipsilateral IBC was highest after no surgery (6.9, 95%CI:4.9–9.4), lowest after mastectomy (0.2, 95%CI:0.4–0.8).

Conclusion

LCIS incidence increased, surgical treatment decreased. The low mortality risks support consideration of active surveillance. However, the increased IBC incidence suggests careful monitoring.

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The incidence of LCIS increased, while surgical treatment decreased over time.

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10- and 20-year relative survival rates exceeded 90 %, irrespective of surgery.

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The risk of breast cancer was highest after no surgery, lowest after mastectomy.

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Subsequent breast cancers were generally of low stage.

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Active surveillance for LCIS is advised, with the current follow-up five years.

Why is LCIS Important—Pathological Review

Purpose of Review

Lobular carcinoma in situ (LCIS) encompasses classical LCIS and other rarer and more recently recognised variants, namely pleomorphic LCIS (PLCIS) and florid LCIS. Each of those entities has characteristic histological diagnostic criteria, different rates of underestimation of malignancy and recommended management. In addition, those lesions can mimic a number of benign and malignant breast lesions and can particularly be mistaken for ductal carcinoma in situ (DCIS). Accurate diagnosis of those lesions is critical to ensuring the appropriate patient management.

Recent Findings

Several international guidelines refining the pathological classification, staging and management of those lesions have recently been updated. This review will provide an up-to-date pathological overview of the current knowledge of LCIS with emphasis on the multidisciplinary management implications.

Summary

Close correlation between imaging and pathology in a multidisciplinary pathway is essential in LCIS management. Classical LCIS on core biopsy/vacuum-assisted biopsy (VAB) is coded as B3 and, if without discordant imaging, should further be sampled by vacuum-assisted excision (VAE). PLCIS should be coded and managed as per high-grade DCIS. Florid LCIS is a rare entity that is thought to be more aggressive than classical LCIS. Excision with clear margin is advised.

The lobular neoplasia enigma: management and prognosis in a long follow-up case series

BACKGROUND

Many oncologists debate if lobular neoplasia (LN) is a risk factor or an obligatory precursor of more aggressive disease. This study has three aims: (i) describe the different treatment options (surgical resection vs observation), (ii) investigate the upgrade rate in surgically treated patients, and (iii) evaluate the long-term occurrences of aggressive disease in both operated and unoperated patients.

METHODS

A series of 122 patients with LN bioptic diagnosis and follow-up information were selected. Clinical, radiological, and pathological data were collected from medical charts. At definitive histology, either invasive or ductal carcinoma in situ was considered upgraded lesions.

RESULTS

Atypical lobular hyperplasia (ALH), lobular carcinoma in situ (LCIS), and high-grade LN (HG-LN) were diagnosed in 44, 63, and 15 patients, respectively. The median follow-up was 9.5 years. Ninety-nine patients were surgically treated, while 23 underwent clinical-radiological follow-up. An upgrade was observed in 28/99 (28.3%). Age ≥ 54 years (OR 4.01, CI 1.42-11.29, p = 0.009), Breast Imaging-Reporting and Data System (BI-RADS) categories 4-5 (OR 3.76, CI 1.37-10.1, p = 0.010), and preoperatory HG-LN diagnosis (OR 8.76, 1.82-42.27, p = 0.007) were related to upgraded/aggressive disease. During follow-up, 8 patients developed an ipsilateral malignant lesion, four of whom were not initially operated (4/23, 17%).

CONCLUSIONS

BI-RADS categories 4-5, HG-LN diagnosis, and age ≥ 54 years were features associated with an upgrade at definitive surgery. Moreover, 17% of unoperated cases developed an aggressive disease, emphasizing that LN patients need close surveillance due to the long-term risk of breast cancer.

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.

Screening detects a myriad of breast disease - refining practice will increase effectiveness and reduce harm

For many individuals, the term 'cancer' equates to a disease that if untreated will progress, spread from the area initially affected and ultimately cause death. 'Breast cancer', however, is a diverse of range of pathological entities, incorporating indolent to fast-growing and aggressive lesions, with varying histological patterns, clinical presentations, treatment responses and outcomes. Screening for malignancy is based on the assumption that cancer has a gradual, orderly progression and that detecting lesions earlier in their natural history, and intervening, will reduce mortality. The natural history of epithelial atypia, ductal carcinoma in situ and even invasive breast cancer is poorly understood, but widely variable. We believe that population breast screening methodology needs to change to focus on diagnosis of lesions of greatest clinical relevance.

Atypical lobular hyperplasia on core needle biopsy: contemporary results from a large community hospital breast program

PURPOSE

The management of biopsy proven atypical lobular hyperplasia (ALH) is controversial. Although upgrade rates are low, excisional biopsy is often performed to rule out occult breast cancer.

METHODS

In this study, we analyzed our experience with excisional biopsy for ALH diagnosed in the digital tomosynthesis era with radiographic concordance in the community hospital setting. This study included 93 consecutive patients diagnosed with pure ALH on core biopsy from January 2013-December 2017 who underwent subsequent excisional biopsy. Potential clinical, radiographic and pathologic predictors of upgrading were analyzed.

RESULTS

At the time of excisional biopsy, five patients (5.4%) were upgraded to DCIS or invasive breast cancer. There was also a trend towards higher upgrade rates in patients with contralateral breast cancer (p = 0.06), biopsy performed by ultrasound or MRI (p = 0.07) and extensive ALH (p = 0.10). Other clinical, radiographic and pathologic variables were not predictive of upgrade rate (p > 0.1 for all).

CONCLUSION

Patients with pure ALH with radiographic concordance have a low risk of pathologic upgrading on excisional biopsy. Potential predictors of upgrade rate warrant further analysis in a larger dataset.

Three-year Trends in Diagnosis of B3 Breast Lesions and Their Upgrade Rates to Malignant Lesions

BACKGROUND

B3 breast lesions are a heterogeneous group with uncertain malignant potential and, as such, provide a source of diagnostic difficulty. We calculated the prevalence of B3 lesions at our center along with the upgrade rates (positive predictive value) to in situ or invasive malignancy.

MATERIALS AND METHODS

We searched our pathology database over a 3-year period to include all B3 biopsies. The subsequent excision for each biopsy was reviewed, and the rate of upgrade was calculated by subtype. These results were compared against data published in large United Kingdom studies.

RESULTS

A total of 9206 breast biopsies were identified, of which 614 (6.7%) were classified as B3. Lesions displaying epithelial atypia were the most common subtype of lesion, with a prevalence of 39.6%. Lesions displaying epithelial atypia were upgraded to malignancy in 35.7% of cases. Among non-atypical cases, papillary lesions were the most common diagnosis (32.1%) with an upgrade rate of 2%. In situ lobular neoplasia (10.4%) was the third most frequently encountered diagnosis, and was upgraded to malignancy in 10.9% of cases. The upgrade rate in the remaining non-atypical lesions was invariably low (0%-2.6%).

CONCLUSIONS

Herein, we have shown an overall B3 rate in keeping with published data, whereas lesions displaying epithelial atypia showed upgrade rates to malignancy comparable with that of large United Kingdom studies. In our study, lesions without epithelial atypia showed very low rates of upgrade. A wide range of upgrade rates is seen in cases of lobular neoplasia, which highlights the need for uniformity of nomenclature and reporting within this subtype to accurately ascertain the true risk of upgrade associated with these lesions.

Do Body Mass Index and Breast Density Impact Cancer Risk Among Women with Lobular Carcinoma In Situ?

PURPOSE

Both body mass index (BMI) and breast density impact breast cancer risk in the general population. Whether obesity and density represent additive risk factors in women with lobular carcinoma in situ (LCIS) is unknown.

METHODS

Patients diagnosed with LCIS from 1988 to 2017 were identified from a prospectively maintained database. BMI was categorized by World Health Organization classification. Density was captured as the mammographic Breast Imaging Reporting and Data System (BIRADS) value. Other covariates included age at LCIS diagnosis, menopausal status, family history, chemoprevention, and prophylactic mastectomy. Cancer-free probability was estimated using the Kaplan-Meier method, and Cox regression models were used for univariable and multivariable analyses.

RESULTS

A total of 1222 women with LCIS were identified. At a median follow-up of 7 years, 179 women developed breast cancer (121 invasive, 58 ductal carcinoma in situ); 5- and 10-year cumulative incidences of breast cancer were 10% and 17%, respectively. In multivariable analysis, increased breast density (BIRADS C/D vs. A/B) was significantly associated with increased hazard of breast cancer (hazard ratio [HR] 2.42, 95% confidence interval [CI] 1.52-3.88), whereas BMI was not. On multivariable analysis, chemoprevention use was associated with a significantly decreased hazard of breast cancer (HR 0.49, 95% CI 0.29-0.84). Exploratory analyses did not demonstrate significant interaction between BMI and menopausal status, BMI and breast density, BMI and chemoprevention use, or breast density and chemoprevention.

CONCLUSIONS

Breast cancer risk among women with LCIS is impacted by breast density. These results aid in personalizing risk assessment among women with LCIS and highlight the importance of chemoprevention counseling for risk reduction.

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 < .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.

Personal history of proliferative breast disease with atypia and risk of multifocal breast cancer

BACKGROUND

A history of proliferative breast disease with atypia (PBDA) may be indicative of an increased risk not just of breast cancer but also of a more aggressive form of breast cancer.

METHODS

Multifocal breast cancer (MFBC), defined as 2 or more tumors in the same breast upon a diagnosis of cancer, is associated with a poorer prognosis than unifocal (single-tumor) breast cancer. PBDA, including atypical ductal hyperplasia and atypical lobular hyperplasia, is a known risk factor for breast cancer. Using New Hampshire Mammography Network data collected for 3567 women diagnosed with incident breast cancer from 2004 to 2014, this study assessed the risk of MFBC associated with a previous diagnosis of PBDA.

RESULTS

Women with a history of PBDA were found to be twice as likely to be subsequently diagnosed with MFBC as women with no history of benign breast disease (BBD; odds ratio [OR], 2.23; 95% confidence interval [CI], 1.08-4.61). Ductal carcinoma in situ on initial biopsy was associated with a 2-fold increased risk of MFBC in comparison with invasive cancer (OR, 2.13; 95% CI, 1.58-2.88). BBD and proliferative BBD without atypia were not associated with MFBC.

CONCLUSIONS

Women with a history of previous PBDA may be at increased risk for MFBC. Women with a history of PBDA may benefit from additional presurgical clinical workup. Cancer 2018;124:1350-7. © 2017 American Cancer Society.

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.

Pleomorphic LCIS what do we know? A UK multicenter audit of pleomorphic lobular carcinoma in situ

AIMS

Pleomorphic lobular carcinoma in situ (PLCIS) is a relatively newly described pathological lesion that is distinguished from classical LCIS by its large pleomorphic nuclei. The lesion is uncommon and its appropriate management has been debated. The aim of this study is to review data from a large series of PLCIS to examine its natural history in order to guide management plans.

MATERIALS AND METHODS

Comprehensive pathology data were collected from two cohorts; one from a UK multicentre audit and the other a series of PLCIS cases identified from within the GLACIER study cohort. 179 cases were identified of whom 176 had enough data for analysis.

RESULTS

Out of these 176 cases, 130 had invasive disease associated with PLCIS, the majority being of lobular type (classical and/or pleomorphic). A high incidence of histological grade 2 and 3 invasive cancers was noted with a predominance of ER positive and HER-2 negative malignancy. When PLCIS was the most significant finding on diagnostic biopsy the upgrade to invasive disease on excision was 31.8%, which is higher than pooled data for classical LCIS and DCIS.

CONCLUSION

The older age at presentation, high grade of upgrade to invasive cancer, common association with higher grade tumours suggest that PLCIS is an aggressive form of insitu disease. These findings support the view that PLCIS is a more aggressive form of lobular in situ neoplasia and supports the tendency to treat akin to DCIS.

Isolated Atypical Lobular Hyperplasia Diagnosed on Breast Biopsy: Low Upgrade Rate on Subsequent Excision With Long-Term Follow-up

Context.—

The upgrade rate to carcinoma on excision for atypical lobular hyperplasia diagnosed on breast biopsy is controversial.

Objective.—

To review cases with isolated atypical lobular hyperplasia on biopsy to establish the rate of upgrade on excision and correlate with long-term follow-up.

Design.—

A database search was performed for 191 months to identify breast core biopsies with isolated atypical lobular hyperplasia. Cases with other atypical lesions in the biopsy or discordant radiologic-pathologic findings were excluded. Invasive carcinoma and ductal carcinoma in situ were considered upgraded pathology on excision. Patients without and with a history of, or concurrent diagnosis of, breast carcinoma were compared.

Results.—

Eighty-seven cases of isolated atypical lobular hyperplasia on biopsy underwent subsequent excision, which resulted in 3 upgraded cases (3.4%). All 3 cases with immediate upgrades revealed ductal carcinoma in situ. Upgrade was higher in patients with a concurrent diagnosis of breast carcinoma (2 of 26 and 1 of 61; 7.7% versus 1.6%, respectively). Follow-up information was available for 63 patients (57.8 ± 43.9 months; range, 6–183 months). Overall, 13% of patients without a history of breast carcinoma had a future breast cancer event, with the majority (83%) presenting in the contralateral breast.

Conclusions.—

With careful radiologic-pathologic correlation, the upgrade rate for isolated atypical lobular hyperplasia on biopsy is low, and a more conservative approach may be appropriate.

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.

Benign Breast Diseases: Evaluation and Management

Benign breast disease is a spectrum of common disorders. The majority of patients with a clinical breast lesion will have benign process. Management involves symptom control when present, pathologic-based and imaging-based evaluation to distinguish from a malignant process, and counseling for patients that have an increased breast cancer risk due to the benign disorder.

Pleomorphic lobular carcinoma in situ: Current evidence and a systemic review

Pleomorphic lobular carcinoma in situ (PLCIS) has only recently been identified as a distinct pathological entity within classic lobular carcinoma in situ (CLCIS). As such, there is currently no consensus among clinicians regarding the optimal treatment of this disease. The present study determined the risk of concomitant invasive disease and ductal carcinoma in situ (DCIS) if PLCIS is observed on core needle biopsy (CNB) and collated the evidence regarding the risk of recurrence in relation to surgical margins and adjuvant therapy. In addition, the pertinent literature available through MedLine, PubMed, the WHO Clinical Trials Registry Platform and Google Scholar using appropriate keywords was reviewed. The pooled results of studies in the literature demonstrated a concomitant presence of invasive disease of 40%, and 15% for DCIS. The studies that examined recurrence rates indicated that the risk is reduced with ample resection margins (>2 mm) and adjuvant radiotherapy. However, recent studies raise concerns regarding breast conservation when pursuing clear margins. No level 1 evidence from prospective studies, randomized controlled trials (RCTs), or meta-analyses based on such RCTs was identified. This is a clinical issue that warrants investigation in appropriately powered well designed prospective studies for a satisfactory resolution of all concerns.

Lobular neoplasia diagnosed on breast Core biopsy: frequency of carcinoma on excision and implications for management

The appropriate follow-up and treatment for patients with a core biopsy diagnosis of lobular neoplasia (atypical lobular hyperplasia or lobular carcinoma in situ) remains controversial. Several studies have attempted to address this issue, with recommendations ranging from close clinical follow-up or surveillance to mandatory surgical excision in all cases. We report the findings at our institution, where virtually every core needle biopsy diagnosis of lobular neoplasia results in follow-up excision. The goal of the study was to identify potential predictors of upgrade to a more significant lesion. We identified 76 patients over a 15-year period with a core biopsy diagnosis of pure lobular neoplasia and no other high-risk lesions. Subsequent surgical excision identified 10 cases (13%) that were upgraded to carcinoma. Upgrade diagnoses included invasive ductal carcinoma (n=1), invasive lobular carcinoma (n=4), ductal carcinoma in situ (n=3), and pleomorphic lobular carcinoma in situ (n=2). All 10 upgraded cases had imaging findings suspicious for malignancy including irregular masses, asymmetric densities, or pleomorphic calcifications. Of the 10 upgraded cases, 7 were diagnosed as lobular carcinoma in situ on core biopsy. The data support a role for radiologic-pathologic correlation in the evaluation of suspicious breast lesions and suggest that the extent of lobular neoplasia in core biopsy specimens may be an indicator of the likelihood of upgrade to carcinoma.

Atypical epithelial hyperplasia of the breast: state of the art

INTRODUCTION

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

AREAS COVERED

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

Clonal relationships between lobular carcinoma in situ and other breast malignancies

Background

Recent evidence suggests that lobular carcinoma in situ (LCIS) can be a clonal precursor of invasive breast cancers of both the ductal and lobular phenotypes. We sought to confirm these findings with an extensive study of fresh frozen breast specimens from women undergoing mastectomy.

Methods

Patients with a history of LCIS presenting for therapeutic mastectomy were identified prospectively. Frozen tissue blocks were collected, screened for lesions of interest, and subjected to microdissection and DNA extraction. Copy number profiling, whole-exome sequencing, or both were performed. Clonal relatedness was assessed using specialized statistical techniques developed for this purpose.

Results

After exclusions for genotyping failure, a total of 84 lesions from 30 patients were evaluated successfully. Strong evidence of clonal relatedness was observed between an LCIS lesion and the invasive cancer for the preponderance of cases with lobular carcinoma. Anatomically distinct in situ lesions of both ductal and lobular histology were also shown to be frequently clonally related.

Conclusions

These data derived from women with LCIS with or without invasive cancer confirm that LCIS is commonly the clonal precursor of invasive lobular carcinoma and that distinct foci of LCIS frequently share a clonal origin, as do foci of LCIS and ductal carcinoma in situ.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-016-0727-z) contains supplementary material, which is available to authorized users.

Expression of DDR1 and DVL1 in invasive ductal and lobular breast carcinoma does not correlate with histological type, grade and hormone receptor status

BACKGROUND

Invasive ductal (IDC) and lobular (ILC) carcinomas are the common histological types of breast carcinoma which are difficult to distinguish when poorly differentiated. Discoidin domain receptor (DDR1) and Drosophila dishevelled protein (DVL1) were recently suggested to differentiate IDC from ILC.

OBJECTIVES

To assess the expression of DDR1 and DVL1 and their association with histological type, grading and hormonal status of IDC and ILC.

MATERIALS AND METHODS

This cross sectional study was conducted on IDC and ILC breast tumours. Tumours were immunohistochemically stained for (DDR1) and (DVL1) as well as estrogen receptor (ER), progesterone receptor (PR) and C-erbB2 receptor. Demographic data including age and ethnicity were obtained from patient records.

RESULTS

A total of 51 cases (30 IDCs and 21 ILCs) were assessed. DDR1 and DVL1 expression was not significantly associated with histological type (p=0.57 and p=0.66 respectively). There was no association between DDR1 and DVL1 expression and tumour grade (p=0.32 and p=1.00 respectively), ER (p=0.62 and 0.50 respectively), PR (p=0.38 and p=0.63 respectively) and C-erbB2 expression (p=0.19 and p=0.33 respectively) in IDC. There was no association between DDR1 and DVL1 expression and tumour grade (p=0.52 and p=0.33 respectively), ER (p=0.06 and p=0.76 respectively), PR (p=0.61 and p=0.43 respectively) and C-erbB2 expression (p=0.58 and p=0.76 respectively) in ILC.

CONCLUSIONS

This study revealed that DDR1 and DVL1 are present in both IDC and ILC regardless of the tumour differentiation. More studies are needed to assess the potential of these two proteins in distinguishing IDC from ILC in breast tumours.

Pleomorphic Lobular Carcinoma In Situ: Radiologic-Pathologic Features and Clinical Management

BACKGROUND

Pleomorphic lobular carcinoma in situ (PLCIS) is an unusual variant of LCIS for which optimal management remains unclear.

METHODS

We conducted a 15-year (2000-2014) retrospective chart review of the radiologic, pathologic, clinical management, and recurrence rates of patients with PLCIS on diagnostic biopsy. Fifty-one patients were found to have PLCIS either alone or with concomitant breast cancer. Of these, 23 were found to have pure PLCIS on diagnostic biopsy. Rates of upstaging after local excision, positive or close margins, mastectomy, and recurrence associated with pure pleomorphic lobular carcinoma in situ were examined.

RESULTS

Of the 21 patients who underwent surgical excision following diagnostic biopsy, 33.3 % (7/21) were found to have invasive carcinoma, and 19 % (4/23) were found to have ductal carcinoma in situ. Extensive or multifocal PLCIS was present in 47.6 % (10/21) of patients, corresponding to at least one PLCIS-positive or close margin in 71.4 % (15/21). In total, there were 11 local re-excisions in nine patients, and 12 mastectomies. No ipsilateral breast cancer events have occurred, including in those with positive or close surgical margins (mean follow-up 4.1 years).

CONCLUSIONS

Patients with isolated PLCIS on diagnostic biopsy are at high risk of upgrading to invasive cancer or ductal carcinoma in situ at diagnostic excision. PLCIS often is extensive, with high rates of positive or close surgical resection margins. If negative PLCIS margins are pursued, rates of successful breast conservation are low. In light of this and low recurrence rates, caution should be exercised in aggressively treating PLCIS with excision to clear margins.

Lesions of uncertain malignant potential in the breast (B3): what do we know?

Breast lesions classified as of uncertain malignant potential (B3) on biopsy form a diverse group of abnormalities, which pose a diagnostic and management challenge. In this paper, we discuss the imaging and pathology features as well as the management of the most controversial B3 lesions, consisting of papillary lesions, complex sclerosing lesions/radial scars, lobular intraepithelial neoplasia, and atypical epithelial proliferation of ductal type. As there is an association with malignancy at the time of diagnosis, as well as an increase in the risk of subsequent development of cancer, a multidisciplinary discussion is almost always required to tailor treatment.

[Benign proliferative breast disease with and without atypia]

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

UK national survey of management of breast lobular carcinoma in situ

INTRODUCTION

There is no national standard treatment for patients with breast lobular carcinoma in situ (LCIS). Association of Breast Surgery guidelines for the management of breast cancer suggest that lesions containing LCIS should be excised for definitive diagnosis and recommend close surveillance after excision biopsy. The aim of this study was to form a picture of the current management of LCIS by UK breast surgeons.

METHODS

A questionnaire about the management of LCIS was sent to 490 UK breast surgeons.

RESULTS

Of 490 questionnaires sent out, 173 (35%) were returned. When LCIS is present in a core biopsy, 61% of breast surgeons perform surgical excision, 22% would not excise but would continue follow-up and the remainder perform neither or set no clear management plan. Over half (54%) follow patients up with five years of annual mammography. If classic LCIS were found at the margins of wide local excision, 92% would not re-excise. Conversely, if pleomorphic LCIS were found, 71% would achieve clear margins. Respondents were split evenly regarding management of classic LCIS with a family history as 54% would not alter management whereas 43% would treat the disease more aggressively.

CONCLUSIONS

Our survey has shown that in cases where LCIS is found at core biopsy, most surgeons follow Association of Breast Surgery guidance, obtaining further histological samples to exclude pleomorphic LCIS, ductal carcinoma in situ or invasive cancer, whereas others opt for annual surveillance and some discharge the patient. This study highlighted the huge variability in LCIS management, and the need for randomised controlled trials and input into national audits such as the Sloane Project to establish evidence-based national standard guidelines.

Lobular Carcinoma in Situ: A 29-Year Longitudinal Experience Evaluating Clinicopathologic Features and Breast Cancer Risk

PURPOSE

The increased breast cancer risk conferred by a diagnosis of lobular carcinoma in situ (LCIS) is poorly understood. Here, we review our 29-year longitudinal experience with LCIS to evaluate factors associated with breast cancer risk.

PATIENTS AND METHODS

Patients participating in surveillance after an LCIS diagnosis are observed in a prospectively maintained database. Comparisons were made among women choosing surveillance, with or without chemoprevention, and those undergoing bilateral prophylactic mastectomies between 1980 and 2009.

RESULTS

One thousand sixty patients with LCIS without concurrent breast cancer were identified. Median age at LCIS diagnosis was 50 years (range, 27 to 83 years). Fifty-six patients (5%) underwent bilateral prophylactic mastectomy; 1,004 chose surveillance with (n = 173) or without (n = 831) chemoprevention. At a median follow-up of 81 months (range, 6 to 368 months), 150 patients developed 168 breast cancers (63% ipsilateral, 25% contralateral, 12% bilateral), with no dominant histology (ductal carcinoma in situ, 35%; infiltrating ductal carcinoma, 29%; infiltrating lobular carcinoma, 27%; other, 9%). Breast cancer incidence was significantly reduced in women taking chemoprevention (10-year cumulative risk: 7% with chemoprevention; 21% with no chemoprevention; P < .001). In multivariable analysis, chemoprevention was the only clinical factor associated with breast cancer risk (hazard ratio, 0.27; 95% CI, 0.15 to 0.50). In a subgroup nested case-control analysis, volume of disease, which was defined as the ratio of slides with LCIS to total number of slides reviewed, was also associated with breast cancer development (P = .008).

CONCLUSION

We observed a 2% annual incidence of breast cancer among women with LCIS. Common clinical factors used for risk prediction, including age and family history, were not associated with breast cancer risk. The lower breast cancer incidence in women opting for chemoprevention highlights the potential for risk reduction in this population.

Lobular carcinoma in situ (LCIS) of the breast: is long-term outcome similar to ductal carcinoma in situ (DCIS)? Analysis of 200 cases

Background

Lobular carcinomas in situ (LCIS) represent 1-2% of all breast cancers. Both significance and treatment remain widely debated, as well as the possible similarities with DCIS.

Materials and methods

Two hundred patients with pure LCIS were retrospectively analyzed in seven centres from 1990 to 2008. Median age was 52 years; 176 patients underwent breast-conserving surgery (BCS) and 24 mastectomy. Seventeen patients received whole breast irradiation (WBRT) after BCS and 20 hormonal treatment (15 by tamoxifen).

Results

With a 144-month median follow-up (FU), there were no local recurrences (LR) among 24 patients treated by mastectomy. With the same FU, 3 late LR out of 17 (17%) occurred in patients treated by BCS and WBRT (with no LR at 10 years). Among 159 patients treated by BCS alone, 20 developed LR (13%), but with only a 72-month FU (17.5% at 10 years). No specific LR risk factors were identified. Three patients developed metastases, two after invasive LR; 22 patients (11%) developed contralateral BC (59% invasive) and another five had second cancer.

Conclusions

LCIS is not always an indolent disease. The long-term outcome is quite similar to most ductal carcinomas in situ (DCIS). The main problems are the accuracy of pathological definition and a clear identification of more aggressive subtypes, in order to avoid further invasive LR. BCS + WBRT should be discussed in some selected cases, and the long-term results seem comparable to DCIS.

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

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

Lobular neoplasia: morphology and management

CONTEXT

Lobular neoplasia encompasses a spectrum of disease, including atypical lobular hyperplasia and lobular carcinoma in situ. Although classic forms of lobular neoplasia are predominantly heralded as a risk marker, the pleomorphic form of lobular carcinoma in situ is generally regarded as a more aggressive subtype and a possible cancer precursor, and thus is treated in a manner more similar to ductal carcinoma in situ than classic forms of lobular neoplasia.

OBJECTIVE

To focus on the morphologic spectrum of lobular neoplasia as highlighted by 3 cases and current management recommendations. Areas of diagnostic challenge and controversy are addressed.

DATA SOURCES

A review of the pertinent published literature and current national guidelines was conducted.

CONCLUSIONS

Correct classification of classic lobular neoplasia and pleomorphic lobular carcinoma in situ is critical because of differences in clinical management, with current treatment strategies focused on risk reduction for patients with classic lobular neoplasia and eradication of the lesion for those with pleomorphic lobular carcinoma in situ.

Pleomorphic lobular carcinoma in situ of the breast: Can the evidence guide practice?

The clinical significance of pleomorphic lobular carcinoma in situ (PLCIS) is a subject of controversy. As a consequence, there is a risk of providing inconsistent management to patients presenting with PLCIS. This review aims to establish whether the current guidelines for the management of PLCIS are consistent with current evidence. A systematic electronic search was performed to identify all English language articles regarding PLCIS management. The data was analysed, specifically looking at: incidence of concurrent disease, recurrence rates, long-term prognosis and PLCIS management. A search was also performed for PLCIS management guidelines for the United Kingdom, United States, Canada, Australia, Germany and pan-European. The results of the evidence analyses were compared to the guidelines in order to establish whether the recommended management is consistent with the published evidence. Nine studies (level 3-4 evidence), involving a total of 176 patients and five management guidelines (from United Kingdom, United States, Australia and pan-European) were included in the review. From the evidence, 46 of 93 (49%) patients were found to have PLCIS with concurrent invasive disease on excision specimen analysis. Regarding recurrence rates, 11 of 117 (9.4%) patients developed a recurrence of PLCIS. There were no instances of invasive disease or ductal carcinoma in situ (DCIS) on recurrence histology. There were no studies assessing long-term outcomes in PLCIS cases. With regards to the management guidelines, the Association of Breast Surgery (United Kingdom) and the National Breast and Ovarian Cancer Care (Australia) do not mention PLCIS. The National Comprehensive Cancer Network (United States) suggest considering excision of PLCIS with negative margins. The NHS Breast Screening Programme (United Kingdom) and the European Society of Medical Oncology (pan-European) recommend PLCIS should be treated as with DCIS. We conclude that high quality evidence to inform guidance is lacking, thus recommendations are relatively vague. However, based on the available evidence, it would seem prudent to treat PLCIS in a similar manner to DCIS.

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

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

Underestimation rate of lobular intraepithelial neoplasia in vacuum-assisted breast biopsy

OBJECTIVES

To evaluate the underestimation rate and clinical relevance of lobular neoplasia in vacuum-assisted breast biopsy (VABB).

METHODS

A total of 161 cases of LN were retrieved from 6,435 VABB. The histological diagnosis was ALH (atypical lobular hyperplasia) in 80 patients, LCIS (lobular carcinoma in situ) in 69 patients and PLCIS (pleomorphic lobular carcinoma in situ) in 12 patients. Seventy-six patients were operated on within 2 years after VABB and 85 were clinically and radiologically monitored. The mean follow-up was 5.2 years, and the prevalence of malignancy was evaluated in the group of 85 patients.

RESULTS

The clinico-pathological characteristics significantly favouring surgery were larger lesions, occurrence of a residual lesion following VABB and histological LCIS and PLCIS subtypes. The VABB underestimation rate as compared to surgery was 7.1% for ALH, 12% for LCIS and 50% for PLCIS. Overall, 11 of the 148 patients included in this survival analysis developed an ipsilateral tumour.

CONCLUSION

Although obtained retrospectively in a relatively small series of patients, our data suggest that only patients with a diagnosis of PLCIS in VABB should be treated with surgery, whereas patients with ALH and LCIS could be monitored by clinical and radiological examinations.

KEY POINTS

• The treatment of ALH and LCIS in VABB is still debated • Some authors favour radical treatment and others a more conservative approach • Only patients with PLCIS in VABB should be treated by surgery.

Lobular neoplasia

Lobular neoplasia (LN) is characterized by a dysfunctional E-cadherin-catenin axis, and loss of E-cadherin plays a causative role in the typical morphology of LN cells. LN is both a nonobligate precursor and a risk indicator of invasive breast cancer, and in particular, of invasive lobular carcinoma. Despite the evidence supporting the precursor role of LN, its impact on clinical management has been a matter of controversy, and conservative management remains the mainstay of treatment. In this article, an update is provided on the pathology and genetics of LN, and the management of these lesions in surgical practice is discussed.

Evolving concepts in breast lobular neoplasia and invasive lobular carcinoma, and their impact on imaging methods

Invasive lobular carcinoma (ILC) and lobular neoplasia (LN) are two distinct conditions that still pose challenges regarding to their classification, diagnosis and management. Although they share similar cellular characteristics, such as discohesive neoplastic cells and absence of e-cadherin staining, they represent completely different conditions. LN encompasses atypical lobular hyperplasia (ALH) and lobular carcinoma in situ (LCIS), which are currently considered risk factors and non-obligatory precursors of breast neoplasia. These lesions are diagnosed as incidental findings in percutaneous biopsies or appear as non-specific clusters of punctate calcifications in mammograms. ILC is the second most common breast malignancy and has typical histological features, such as infiltrative growth and low desmoplasia. These histological features are reflected in imaging findings and constitute the reasons for typical subtle mammographic features of ILC, as architectural distortion or focal asymmetries. Ultrasonography (US) may detect almost 75 % of the ILCs missed by mammography and represents the modality of choice for guiding biopsies. Magnetic resonance imaging (MRI) exhibits a high sensitivity for the diagnosis of ILC and for detecting synchronous lesions.

Teaching Points

• LN includes ALH and LCIS, risk factors and non-obligatory precursors of breast cancer.

• Absence of e-cadherin staining is crucial for differentiation among ductal and lobular lesions.

• ILC has typical histological features, such as infiltrative growth and low desmoplasia.

• Mammographic features of ILC are often subtle and reflect the histological features.

• MRI exhibits a high sensitivity for the diagnosis of ILC and for detecting synchronous lesions.