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.

Initiation and tolerance of chemoprevention among women with high-risk breast lesions: the potential of low-dose tamoxifen.

PURPOSE: High-risk lesions (HRLs) of the breast are an indication for chemoprevention, yet uptake is low, largely due to concerns about side effects. In 2019, low-dose (5 mg) tamoxifen was demonstrated to reduce breast cancer risk with improved tolerance. We describe chemoprevention uptake in an academic clinic before and after the introduction of low-dose tamoxifen. METHODS: Females age ≥ 35 with HRLs who established care from April 2017 through January 2020 and eligible for chemoprevention were included. Rates of chemoprevention initiation before and after the introduction of low-dose tamoxifen (pre-2019 vs. post-2019) were compared with chi-squared tests. Logistic regression identified demographic and clinical factors associated with chemoprevention initiation. Kaplan-Meier methods determined the rates of discontinuation. RESULTS: Among 660 eligible females with HRLs, 22.7% initiated chemoprevention. Median time from first visit to chemoprevention initiation was 54 days (interquartile range (IQR): 0-209); 31.0% (46/150) started chemoprevention > 6 months after their initial visit. Chemoprevention uptake was not significantly different pre-2019 vs. post-2019 (21.2% vs. 26.3%, p = 0.16); however, post-2019, low-dose tamoxifen became the most popular option (41.5%, 34/82). On multivariable analyses, age and breast cancer family history were significantly associated with chemoprevention initiation. Discontinuation rates at 1 year were lowest for low-dose tamoxifen (6.7%) vs. tamoxifen 20 mg (15.0%), raloxifene (20.4%), or an aromatase inhibitor (20.0%). CONCLUSION: In this modern cohort, 22.7% of females with HRLs initiated chemoprevention with 31.0% initiating chemoprevention > 6 months after their first visit. Low-dose tamoxifen is now the most popular choice for chemoprevention, with low discontinuation rates at 1 year.

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.

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.

Contrast-Enhanced Digital Mammography Screening for Intermediate-Risk Women With a History of Lobular Neoplasia.

OBJECTIVE. The objective of this study was to assess to the role of contrast-enhanced digital mammography (CEDM) as a screening tool in women at intermediate risk for developing breast cancer due to a personal history of lobular neoplasia without additional risk factors. MATERIALS AND METHODS. In this institutional review board-approved, observational, retrospective study, we reviewed our radiology department database to identify patients with a personal history of breast biopsy yielding lobular neoplasia who underwent screening CEDM at our institution between December 2012 and February 2019. A total of 132 women who underwent 306 CEDM examinations were included. All CEDM examinations were interpreted by dedicated breast imaging radiologists in conjunction with a review of the patient's clinical history and available prior breast imaging. In statistical analysis, sensitivity, specificity, NPV, positive likelihood ratio, and accuracy of CEDM in detecting cancer were determined, with pathology or 12-month imaging follow-up serving as the reference standard. RESULTS. CEDM detected cancer in six patients and showed an overall sensitivity of 100%, specificity of 88% (95% CI, 84-92%), NPV of 100%, and accuracy of 88% (95% CI, 84-92%). The positive likelihood ratio of 8.33 suggested that CEDM findings are 8.3 times more likely to be positive in an individual with breast cancer when compared with an individual without the disease. CONCLUSION. CEDM shows promise as a breast cancer screening examination in patients with a personal history of lobular neoplasia. Continued investigation with a larger patient population is needed to determine the true sensitivity and positive predictive value of CEDM for these patients.

Longitudinal study of breast cancer risk markers.

Atypical hyperplasia (AH) and lobular carcinoma in situ (LCIS) are markers for an increased risk of breast cancer, yet outcomes for these diagnoses are not well-documented. In this study, all breast biopsies performed for radiologic abnormalities over a 10-year period were reviewed. Patients with AH or LCIS were followed for an additional 10 years to assess subsequent rates of cancer diagnosis. Long-term follow-up showed that 25 (7.8%) patients with AH and 5 patients with LCIS (5.7%) developed breast cancer over the follow-up period, a lower rate of breast cancer development than predicted by risk models.

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.

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.

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.

Non-invasive lobular neoplasia of the breast: Morphologic features, clinical presentation, and management dilemmas.

The designation of noninvasive lobular neoplasia applies to atypical epithelial proliferations composed of noncohesive cells secondary to loss or functional alteration of E-cadherin-mediated cell adhesion. The morphologic spectrum of noninvasive lobular neoplasia encompasses atypical lobular hyperplasia (ALH) and classic lobular carcinoma in situ (classic LCIS) and two LCIS variants, namely florid LCIS (F-LCIS) and pleomorphic LCIS (P-LCIS), as defined in the World Health Organization (WHO) Classification of Tumors of the Breast 5th ed. Herein, we review the morphologic, immunohistochemical, and molecular features of noninvasive lobular neoplasia, with special emphasis on F-LCIS and P-LCIS. We also review imaging features, management at core needle biopsy, upgrade rates at surgical excision, and clinical management dilemmas.

Breast cancer risk associated with atypical hyperplasia and lobular carcinoma in situ initially diagnosed on core-needle biopsy.

BACKGROUND: Breast cancer risk estimates for atypical lesions are based primarily on case-control studies of patients with open biopsies. The authors report the cumulative breast cancer incidence after a core biopsy diagnosis of atypical hyperplasia (ductal or lobular) or lobular carcinoma in situ. METHODS: A cohort study with central pathology review was conducted on 393 patients who had core biopsy diagnoses of atypical hyperplasia and lobular carcinoma in situ from 1995 through 2010. Follow-up was available for 255 of 264 patients (97%) at a median of 87 months (range, 3-236 months). RESULTS: There were 212 patients (54%) who were not upgraded on excision and had no personal history of breast cancer. Of these, 21 of 212 (9.9%) developed breast cancer, including 15 invasive carcinomas, 4 ductal carcinomas in situ, 1 pleomorphic lobular carcinoma in situ, and 1 unknown type. The prior core biopsy diagnoses were atypical ductal hyperplasia for 11 patients (52%) and atypical lobular hyperplasia/lobular carcinoma in situ in the remaining 10 patients (48%). The number of atypical foci in the core biopsy was not significantly associated with the subsequent development of breast cancer (P = .42). Of the 15 invasive carcinomas, 11 (73%) were ipsilateral, 11 (73%) were pathologic T1 tumors, 5 (33%) were pathologic N1 tumors, 13 (87%) were estrogen receptor-positive, and 1 (7%) was amplified for human epidermal growth factor receptor 2. CONCLUSIONS: In patients who had an initial diagnosis of atypical hyperplasia or lobular carcinoma in situ on core biopsy, the 7-year cumulative breast cancer incidence was 9.9%. Most tumors were ipsilateral, stage I, estrogen receptor-positive, invasive carcinomas. The current data support close clinical and radiologic follow-up for more than 5 years in this patient population. Cancer 2018;124:459-65. © 2017 American Cancer Society.

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.

How Do We Approach Benign Proliferative Lesions?

PURPOSE OF REVIEW: The aim of this review is to summarize recently published literature addressing atypical ductal hyperplasia (ADH), lobular neoplasia (atypical lobular hyperplasia [ALH] and classic lobular carcinoma in situ [C-LCIS]), non-classic lobular carcinoma in situ (NC-LCIS), papillary lesions, and flat epithelial atypia (FEA). RECENT FINDINGS: While ADH, ALN, and C-LCIS are well-established markers of an increased risk of future breast cancers, the risk implications are less clear for papillary lesions and FEA. NC-LCIS is the least well-characterized lesion, with scant published literature on its natural history and surgical management when encountered on needle biopsy. Recent data suggest that lobular neoplasia on core biopsy of a BI-RADS ≤ 4 concordant lesion does not require an excision, while ADH, atypical papillomas, and NC-LCIS should be excised. Evidence on FEA and papillomas without atypia suggests a low risk of upgrade on excision, and prospective studies on the upgrade of these lesions are ongoing.

Extent of atypical hyperplasia stratifies breast cancer risk in 2 independent cohorts of women.

BACKGROUND: Women with atypical hyperplasia (AH) on breast biopsy have a substantially increased risk of breast cancer (BC). Here the BC risk for the extent and subtype of AH is reported for 2 separate cohorts. METHODS: All samples containing AH were included from 2 cohorts of women with benign breast disease (Mayo Clinic and Nashville). Histology review quantified the number of foci of atypical ductal hyperplasia (ADH) and atypical lobular hyperplasia (ALH). The BC risk was stratified for the number of AH foci within AH subtypes. RESULTS: The study included 708 Mayo AH subjects and 466 Nashville AH subjects. In the Mayo cohort, an increasing number of foci of AH was associated with a significant increase in the risk of BC both for ADH (relative risks of 2.61, 5.21, and 6.36 for 1, 2, and ≥3 foci, respectively; P for linear trend = .006) and for ALH (relative risks of 2.56, 3.50, and 6.79 for 1, 2, and ≥3 foci, respectively; P for linear trend = .001). In the Nashville cohort, the relative risks of BC for ADH were 2.70, 5.17, and 15.06 for 1, 2, and ≥3 foci, respectively (P for linear trend < .001); for ALH, the relative risks also increased but not significantly (2.61, 3.48, and 4.02, respectively; P = .148). When the Mayo and Nashville samples were combined, the risk increased significantly for 1, 2, and ≥3 foci: the relative risks were 2.65, 5.19, and 8.94, respectively, for ADH (P < .001) and 2.58, 3.49, and 4.97, respectively, for ALH (P = .001). CONCLUSIONS: In 2 independent cohort studies of benign breast disease, the extent of atypia stratified the long-term BC risk for ADH and ALH. Cancer 2016;122:2971-2978. © 2016 American Cancer Society.

Core Breast Biopsies Showing Lobular Carcinoma In Situ Should Be Excised and Surveillance Is Reasonable for Atypical Lobular Hyperplasia.

OBJECTIVE: The purpose of this article is to determine the upgrade rate to ductal carcinoma in situ (DCIS) or invasive carcinoma at excision at the same site after percutaneous breast biopsy findings of atypical lobular hyperplasia (ALH) or lobular carcinoma in situ (LCIS) using current imaging and strict pathologic criteria. MATERIALS AND METHODS: From January 2006 through September 2013, 32,960 breast core biopsies were performed; 1084 (3.3%) core biopsies found ALH or classic LCIS. For 447 lesions in 433 women, this was the only high-risk lesion at that site, with no ipsilateral malignancy, and results of excision were available. RESULTS: Among the 447 lesions, 22 (4.9%) were malignant at excision, including 10 invasive carcinomas (two grade 2 and eight grade 1; all node negative) and 12 DCIS. The upgrade rate of LCIS was 9.3% (10/108; 95% CI, 5.1-16.2%) and that of ALH was 3.5% (12/339; 95% CI, 2.0-6.1%; p = 0.02). After excluding five cases with radiologic-pathologic discordance and reclassifying one core from ALH to LCIS at review, the upgrade rate for LCIS remained higher (8.4%; 9/107; 95% CI, 4.5-15.2%) than that for ALH (2.4%; 8/335; 95% CI, 1.2-4.6%; p = 0.01). CONCLUSION: Excision is recommended for LCIS on core biopsy because of its 8.4-9.3% upgrade rate. Excluding discordant cases, patients with other high-risk lesions or concurrent malignancy, the risk of upgrade of ALH was 2.4%. Surveillance at 6, 12, and 24 months can be performed in lieu of excision because a short delay in diagnosis of the few malignancies is not expected to cause harm.

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.

Screening breast magnetic resonance imaging in women with atypia or lobular carcinoma in situ.

BACKGROUND: Atypical lesions and lobular carcinoma in situ (LCIS) are associated with an increased risk of breast malignancy. The utility of breast magnetic resonance imaging (MRI) screening in this cohort of women after excision of a high-risk lesion has not been previously established. The objective of this study was to investigate outcomes of breast MRI surveillance in this subgroup of high-risk patients. MATERIALS AND METHODS: We performed a retrospective review of women who required excision of an atypical lesion or LCIS who underwent at least one screening breast MRI from April 2005-December 2011. We collected information on demographics, number of second-look imaging studies recommended, number of biopsies performed and pathologic outcomes. RESULTS: A total of 179 patients met the inclusion criteria, including 131 (73%) with atypical lesions and 48 (27%) with LCIS. Second-look imaging was recommended for 31 of 131 (23.7%) patients with atypical lesions and 8 of 48 (16.7%) with LCIS. Ten biopsies were performed in the atypical cohort (7.6%) with two revealing a malignancy (Positive Predictive Value [PPV] of 20%). In the LCIS cohort, five biopsies were performed (10.4%) with one revealing a malignancy (PPV of 20%). CONCLUSIONS: The benefit of breast MRI surveillance in patients after excision of atypical lesions or LCIS has not been clearly delineated previously. Our data demonstrate that the use of screening breast MRI in this cohort results in additional work-up in one-fifth of patients, but a PPV of only 20%. Large, prospective studies would be needed to determine whether breast cancer outcomes differ between patients undergoing conventional breast screening and those undergoing conventional breast screening plus breast MRI surveillance.

Adenomyoepithelioma of the breast with associated atypical lobular hyperplasia: a previously unrecognized association with management implications.

Adenomyoepitheliomas of breast are rare tumors. We report for the first time a case of an adenomyoepithelioma of the breast with associated lobular neoplasia. A 53-year-old woman had an annual screening mammogram, which identified areas of asymmetry in her left breast at 4-5-o'clock position. Resection of the masses revealed a well-circumscribed, gray-white, firm discrete nodule (0.8 × 0.4 × 0.3 cm). The tumor was composed of both adenomyoepithelial cell hyperplasia and focal atypical lobular hyperplasia. The 2 cell populations had some overlapping histologic features. Immunohistochemical analysis demonstrated a biphasic proliferation with approximately equal parts of luminal epithelial cells with clear and rounded appearance and myoepithelial cells. The myoepithelial component of the proliferation expressed myosin, p63, CK5/6, S-100, and dimly expressed E-cadherin. The epithelial component of the proliferation strongly expressed E-cadherin. In the areas of atypical lobular hyperplasia, there was distinct loss E-cadherin expression. Awareness of this association is highly important to provide these patients adequate follow-up and treatment.

Subsequent percutaneous breast biopsies after initial atypia diagnosis: The patient burden of long-term follow up.

BACKGROUND: Breast atypia increases overall breast cancer risk, potentially necessitating future interventions. This study examines the frequency and outcomes of additional percutaneous biopsies after an atypia diagnosis. METHODS: Adult patients with breast atypia (atypical ductal hyperplasia, atypical lobular hyperplasia, lobular carcinoma in situ) at a single institution were reviewed for subsequent core needle biopsies (CNBs) and corresponding malignant outcomes. RESULTS: Among 432 patients, median age at diagnosis was 54.8 â€‹y. Seventy-one (71/432, 16.4 â€‹%) patients developed a breast malignancy. During a median follow-up of 7.4 â€‹y, 113 patients underwent 149 additional CNBs. Twenty-six patients (26/113, 23.0 â€‹%) had >2 additional CNBs. Approximately half (79/149, 53.0 â€‹%) of all additional CNBs occurred within 5 years after breast atypia diagnosis. CONCLUSION: A considerable number of patients with breast atypia undergo additional percutaneous biopsies, especially within 5 years post-atypia diagnosis. Our study highlights the significant burden of surveillance and the need for tailored follow-up strategies.

Management of screening-detected lobular neoplasia in the era of digital breast tomosynthesis: A preliminary study.

PURPOSE: The purpose of this study is to determine upgrade rates of lobular neoplasia detected by screening digital breast tomosynthesis (DBT) and to determine imaging and clinicopathological features that may influence risk of upgrade. METHODS: Medical records were reviewed of consecutive women who presented with screening DBT-detected atypical lobular hyperplasia (ALH) and/or lobular carcinoma in situ (LCIS) from January 1, 2013, to June 30, 2020. Included patients underwent needle biopsy and had surgery or at least two-year imaging follow-up. Imaging and clinicopathological features were compared between upgraded and nonupgraded cases of lobular neoplasia using the Pearson's chi-squared test and the Wilcoxon signed-rank test. RESULTS: During the study period, 107 women (mean age 55 years, range 40-88 years) with 110 cases of ALH and/or LCIS underwent surgery (80.9%, n = 89) or at least two-year imaging follow-up (19.1%, n = 21). The overall upgrade rate to cancer was 5.5% (6/110), and the upgrade rate to invasive cancer was 3.6% (4/110). The upgrade rate of ALH to cancer was 4.1% (3/74), whereas the upgrade rate of LCIS to cancer was 9.4% (3/32) (p = .28). The upgrade rate of cases presenting as calcifications was 4.2% (3/71), whereas the upgrade rates of cases presenting as noncalcified findings was 7.7% (3/39) (p = .44). CONCLUSIONS: The upgrade rate of screening DBT-detected lobular neoplasia is less than 6%. Surveillance rather than surgery can be considered for lobular neoplasia, particularly in patients with ALH and in those with screening-detected calcifications leading to the diagnosis.