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

Dual-region MRI radiomic analysis indicates increased risk in high-risk breast lesions: bridging intratumoral and peritumoral radiomics for precision decision-making

OBJECTIVE

To evaluate the clinical utility of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)-derived clinicoradiological characteristics and intratumoral/peritumoral radiomic features in predicting pathological upgrades (malignant transformation) in high-risk breast lesions.

MATERIALS AND METHODS

Retrospectively collected the data of 174 patients with high-risk breast lesions who underwent preoperative breast MRI examinations and were confirmed by biopsy pathology in Shenzhen People's Hospital between January 1, 2019 and January 1, 2024. The dataset was randomly divided into a training set (n = 121) and a test set (n = 53) at a ratio of 7:3. Initially, during the second stage of DCE-MRI, the region of interest (ROI) was delineated along the maximum cross-section of the lesion, and then automatically expanded outward by 3 mm, 5 mm, and 7 mm as the peritumoral ROIs. The intratumoral, each peritumoral, and the combined intratumoral and peritumoral radiomic models were established respectively. Independent risk factors predictive of malignant upgrades in high-risk lesions were identified through univariate and multivariable logistic regression analyses, which were subsequently incorporated as clinical and imaging characteristics. Finally, a combined model was established by integrating the intratumoral and peritumoral radiomic features with the clinical and imaging features. The performance of each model was analyzed using the receiver operating characteristic (ROC) curves, and the area under the curve (AUC) was calculated.

RESULTS

The peritumoral 3 mm radiomics model achieved the highest diagnostic performance among all the peritumoral models, with the AUC values of 0.704 and 0.654 for the training and test sets, respectively. In the training set, the combined model showed the highest diagnostic performance (AUC = 0.883), which was superior to that of the clinical and imaging features model (AUC = 0.745, P = 0.003), the intratumoral radiomics model (AUC = 0.791, P = 0.027), the peritumoral 3 mm radiomics model (AUC = 0.704, P = 0.001), and the combined intratumoral and peritumoral radiomic model (AUC = 0.830, P = 0.004). In the test set, the combined model also showed the highest diagnostic performance (AUC = 0.851). The combined model constructed by integrating the intratumoral and peritumoral radiomics features with the clinical and imaging features had the best diagnostic performance, with the sensitivity, specificity, and accuracy of 79.4%, 82.7%, and 81.8% in the training set, and 72.7%, 85.7%, and 83.0% in the test set, respectively.

CONCLUSION

The combined predictive model, which integrates intratumoral and peritumoral radiomic features with clinical and imaging data, exhibited strong diagnostic performance and a clinically applicable nomogram was constructed to stratify individualized upgrade risk, assisting clinicians in making more precise decisions.

Malignant upgrade in lesions of uncertain malignant potential in the breast (B3 lesions) - is open excision always necessary?

PURPOSE

Unclear or suspicious breast findings are typically clarified by interventional breast biopsy. Lesions with uncertain malignant potential are grouped as B3 lesions in histopathology. The B3 group according to the European Working Group for Breast Screening Pathology (EWGBSP) comprises various breast lesions with different upgrade rates to invasive breast cancer (BC) or ductal carcinoma in situ (DCIS) if surgical removal is performed. The objective of this study was to investigate malignant upgrade rates to DCIS and/or invasive breast cancer (BC) after open surgical excision for the different B3 lesions.

METHODS

A total of 192 patients with histologically verified B3 lesions were followed up retrospectively for this analysis. Patients with the B3 lesions atypical ductal hyperplasia (ADH), flat epithelial atypia (FEA), and classical lobular neoplasia (LN1-2) were combined into one group, while cellular fibroepithelial lesions (CFL) and phyllodes tumors without suspicion of malignancy, as well as papillomas and radial scars/complex sclerosing lesions (RS/CSL) were summarized in two other groups. We investigated the association of the different B3 lesions with invasive BC or DCIS after open surgical excision.

RESULTS

Histopathological investigation revealed in 21 (10.9%) of the 192 patients invasive BC or DCIS after open surgical excision. The rate of patients with BC and/or DCIS significantly differed between the patient groups (p < 0.01, Fisher's exact test): The highest rate was 17.5% (95% confidence interval (CI), 10.7-26.2) in patients within the group of ADH, FEA, and LN1-2. In the other two groups, fewer malignant lesions occurred. In the group with papillomas and RS/CSL the malignant upgrade rate was 4.3% (95% CI, 0.9-12.2), while within the group with CFL and phyllodes tumors without suspicion of malignancy no malignant upgrade was observed (0.0%, 95% CI, 0.0-16.9).

CONCLUSIONS

B3 lesions harbor the risk of malignant upgrade after surgical excision. In our collective ADH, FEA, and LN1-2 had significant higher upgrade rates than other B3 lesions.

Florid Lobular Carcinoma In Situ: Imaging Characteristics and Pathologic Upgrade Rates on Surgical Excision

Background: Florid lobular carcinoma in situ is an uncommon lobular neoplasia variant that is frequently associated with invasive carcinoma. However, there remains a paucity of information to guide management. The authors aimed to study imaging features associated with pathologic upgrade rates for patients with florid lobular carcinoma in situ identified on core biopsy undergoing surgical excision. Methods: Patients with florid lobular carcinoma in situ on core biopsy were selected from an institutional pathology database. Patients were excluded if pleomorphic lobular carcinoma in situ was also present on core biopsy. Clinical, radiologic, and pathologic features for each case were reviewed focusing on imaging features which led to core biopsy and those associated with pathologic upgrade on surgical excision. Results: Eighteen cases of florid lobular carcinoma in situ underwent surgical excision. Upgrade rates on surgical excision were higher in cases with suspicious calcifications (8/11, 73%, p=0.049) compared to those without (1/7, 14.3%) and in cases with larger breast lesions (p=0.011). The overall upgrade rate was 50% (9/18), 89% (8/9) with invasive lobular carcinoma and 11% (1/9) with ductal carcinoma in situ. Of the 8 cases with upgrade to invasive lobular carcinoma, 7/8 (87.5%) were Stage I cancers and only 1/8 (12.5%) had macroscopic lymph node involvement and was upgraded to Stage II. Conclusion: Florid lobular carcinoma in situ on core biopsy had an upgrade rate on surgical excision of 50% overall, with 89% of these cases upgraded to invasive lobular carcinoma. Pathologic upgrade was seen more frequently with suspicious calcifications and larger breast lesions. These findings can help guide surgical management of this uncommon lobular neoplasia variant including planning extent of excision and consideration for lymph node evaluation.

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 ​y. Seventy-one (71/432, 16.4 ​%) patients developed a breast malignancy. During a median follow-up of 7.4 ​y, 113 patients underwent 149 additional CNBs. Twenty-six patients (26/113, 23.0 ​%) had >2 additional CNBs. Approximately half (79/149, 53.0 ​%) 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.

"Lobular lesions of the breast: From the classic to the variants"

The aim of this review is to provide the surgical pathologist an overview of lobular lesions, from in situ to invasive carcinoma and the variants, by discussing the epidemiology, clinical characteristics, morphology, immunohistochemistry, known molecular data as well as the treatment recommendations. The recognition of histologic variants of both in situ and invasive lobular carcinoma has expanded the differential diagnosis. Awareness of these different entities is important as treatment recommendations continue to evolve.

Nonneoplastic and neoplastic sclerosing lesions of the breast

Sclerosing lesions of the breast encompass a spectrum of benign and malignant entities and often pose a diagnostic challenge. Awareness of key morphologic features and pitfalls in the assessment of morphology and immunophenotype is essential to avoid over- or underdiagnosis and ensure optimal clinical management. This review summarizes nonneoplastic sclerosing lesions such as radial scar/complex sclerosing lesion, sclerosing adenosis, sclerosing intraductal papilloma, sclerosing variants of ductal adenoma and nipple adenoma, and fibroadenoma with extensive sclerosis, including their clinical presentation, characteristic morphology, differential diagnostic considerations, appropriate immunohistochemical work-up, when needed, and the clinical significance. In addition, atypical or neoplastic entities (such as atypical ductal hyperplasia, ductal carcinoma in situ, low-grade adenosquamous carcinoma, and fibromatosis-like metaplastic carcinoma) that can involve these sclerosing lesions are also briefly discussed.

Immediate and delayed risk of breast cancer associated with classic lobular carcinoma in situ and its variants

OBJECTIVE

To determine the risk of breast cancer due to lobular carcinoma in situ (LCIS).

METHODS

This retrospective IRB-approved study identified cases of LCIS after percutaneous breast biopsy from 7/2005 to 7/2022. Excluded were cases with less than 2 years of imaging surveillance or a concurrent ipsilateral breast cancer diagnosis within 6 months of the LCIS diagnosis. Final outcomes of cancer versus no cancer were determined by pathology at surgical excision or the absence of cancer on imaging surveillance.

RESULTS

A total of 116 LCIS lesions were identified. The primary imaging findings targeted for percutaneous biopsy included calcifications (50.0%, 58/116), MR enhancing lesions (25.0%, 29/116), noncalcified mammographic architectural distortions (10.3%, 12/116), or masses (14.7%, 17/116). Surgical excision was performed in 49.1% (57/116) and imaging surveillance was performed in 50.9% (59/116) of LCIS cases. There were 22 cancers of which 11 cancers were discovered at immediate excision [19.3% (11/57) immediate upgrade] and 11 cancers developed later while on imaging surveillance [18.6% (11/59) delayed risk for cancer]. Among all 22 cancers, 63.6% (14/22) occurred at the site of LCIS (11 at immediate excision and 3 at surveillance) and 36.4% (8/22) occurred at a location away from the site of LCIS (6 in a different quadrant and 2 in the contralateral breast).

CONCLUSION

LCIS has both an immediate risk (19.3%) and a delayed risk (18.6%) for cancer with 90.9% occurring in the ipsilateral breast (63.6% at and 27.3% away from the site of LCIS) and 9.1% occurring in the contralateral breast.

A Comprehensive Assessment of Radial Scars on Core Needle Biopsy in Patients with or without Breast Cancer: Upgrade Rate and Implications on Management

BACKGROUND

Radial scars/radial sclerosing lesions (RS) are benign breast lesions identified on core needle biopsy (CNB) which can upgrade to malignancy at excision. There is limited data on RS detection and upgrade rates with more sensitive imaging such as magnetic resonance imaging (MRI) and none during their detection for breast cancer workup and its implication on patient treatment decisions.

METHODS

A retrospective institutional study of RS diagnosed on CNB between January 2008 and December 2017 was conducted. Clinicopathologic and radiologic features of RS, patient treatment decisions, upgrade rates and long-term follow-up were examined.

RESULTS

We identified 133 patients with RS on CNB, of whom 106 opted for surgery for an upgrade rate to malignancy of 1.9%, 2 patients. Radial scar was diagnosed on mammogram in 60%, MRI in 25% and ultrasound in 15% of patients. In this cohort, 32 patients had their RS detected during breast cancer workup (coexistent group) and they were more likely to have their radial scar detected by MRI (60% vs. 14%, P < .001) and undergo more extensive surgery (94% vs. 75%, P = .02). Among the 27 patients electing observation of their RS, only one (3.7%) developed breast cancer.

CONCLUSIONS

Our results show an extremely low upgrade rate to malignancy of RS, regardless if there is coexisting breast cancer elsewhere. Despite this, RS still prompted more extensive surgical excisions. The findings do not support excision of RS even among breast cancer patients when identified at a separate site from their cancer.

Deep learning of mammogram images to reduce unnecessary breast biopsies: a preliminary study

BACKGROUND

Patients with a Breast Imaging Reporting and Data System (BI-RADS) 4 mammogram are currently recommended for biopsy. However, 70-80% of the biopsies are negative/benign. In this study, we developed a deep learning classification algorithm on mammogram images to classify BI-RADS 4 suspicious lesions aiming to reduce unnecessary breast biopsies.

MATERIALS AND METHODS

This retrospective study included 847 patients with a BI-RADS 4 breast lesion that underwent biopsy at a single institution and included 200 invasive breast cancers, 200 ductal carcinoma in-situ (DCIS), 198 pure atypias, 194 benign, and 55 atypias upstaged to malignancy after excisional biopsy. We employed convolutional neural networks to perform 4 binary classification tasks: (I) benign vs. all atypia + invasive + DCIS, aiming to identify the benign cases for whom biopsy may be avoided; (II) benign + pure atypia vs. atypia-upstaged + invasive + DCIS, aiming to reduce excision of atypia that is not upgraded to cancer at surgery; (III) benign vs. each of the other 3 classes individually (atypia, DCIS, invasive), aiming for a precise diagnosis; and (IV) pure atypia vs. atypia-upstaged, aiming to reduce unnecessary excisional biopsies on atypia patients.

RESULTS

A 95% sensitivity for the "higher stage disease" class was ensured for all tasks. The specificity value was 33% in Task I, and 25% in Task II, respectively. In Task III, the respective specificity value was 30% (vs. atypia), 30% (vs. DCIS), and 46% (vs. invasive tumor). In Task IV, the specificity was 35%. The AUC values for the 4 tasks were 0.72, 0.67, 0.70/0.73/0.72, and 0.67, respectively.

CONCLUSION

Deep learning of digital mammograms containing BI-RADS 4 findings can identify lesions that may not need breast biopsy, leading to potential reduction of unnecessary procedures and the attendant costs and stress.

Increased risk of upstage when combinations of breast lesions of uncertain malignant potential are found on core needle biopsy: The need for surgical excision

BACKGROUND

Management of breast lesions of uncertain malignant potential diagnosed at core needle biopsy (CNB) is controversial due to variable upstage rate (UR) with surgical excision (SE).

METHODS

We performed an IRB-approved retrospective analysis of adult women who underwent CNB demonstrating atypical ductal hyperplasia (ADH), flat epithelial atypia, radial scar, or intraductal papilloma then SE between 2010 and 2022. We evaluated CNB pathology for combination diagnoses (CD), defined as multiple primary lesions or primary with lobular neoplasia (LN), and surgical pathology for upstage.

RESULTS

719 patients were included. UR was 12.2% (88/719). CD experienced higher UR than pure (17.7% (45/254) vs. 9.2% (43/465), p ​= ​0.001). ADH/LN had the highest UR of all CD (34.6% (9/26), p ​= ​0.001). Increased size (15.6 vs. 10.5 ​mm, p ​< ​0.001), distance from nipple (79 vs. 66 ​mm, p ​< ​0.001), and personal history of breast cancer (p ​= ​0.04) were associated with UR.

CONCLUSIONS

CD was associated with increased UR. ADH/LN had the highest UR.

A Retrospective Study of the Epidemiology, Histomorphological Features, Hormonal Status, and Radiological Features of Breast Cancer Diagnosed on Biopsies in Women in Bahrain Up to the Age of 40: A Single-Center Study

BACKGROUND

Breast cancer is the most commonly diagnosed cancer in women worldwide. There are many risk factors that contribute to breast cancer which involve modifiable and non-modifiable factors. Most of the patients diagnosed with breast cancer are over 50 years of age, with breast cancer in women less than 40 years of age being relatively rare and typically more aggressive variants. Moreover, radiological examination is essential for diagnosis and triaging patients for further diagnostic procedures including tissue biopsy sampling. Despite the rarity of malignancy among the younger age group, all of their breast lesions are usually biopsied. Hence, this paper outlines the percentage of benign and malignant breast lesions detected on biopsies obtained from female patients who presented to our hospital before or at the age of 40.

METHODS

 We conducted a single institution retrospective study on 267 breast biopsies done for female patients before or at the age of 40 in the period from January 2020 to January 2023. The data was obtained from the National Health Information System at Salmaniya Medical Complex. The data collected included clinical history, histological, and radiological findings. Data on prognostic markers (estrogen receptor (ER)/progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) status) were also included. The distribution of samples was established according to age ranges, pathological diagnostic categories (B1-5), and prognostic marker interpretation. Further subdivision was performed on cases with malignancy according to tumor grade. The frequency distribution was obtained for ER, PR, and HER status jointly. The association between age and grade, as well as age and categories, was also determined. All the analyses were performed using SPSS Statistics version 26.0 (IBM Corp. Released 2019. IBM SPSS Statistics for Windows, Version 26.0. Armonk, NY: IBM Corp), and the statistical significance was tested at a 5% level.

RESULTS

Out of 267 samples, the majority (62.9%) were in patients with a range of age between 30 and 40. There were 68.5% of samples with the B2 (benign) category, followed by 20.2% with the B5b (malignant-invasive carcinoma) category. Out of 61 malignant samples, there were 17 (6.4%) samples positive on ER and PR but negative on HER2, 16 (6.0%) samples negative on ER, PR, and HER2, eight (3.0%) samples negative on ER and PR negative but positive on HER2, and five (8.2%) samples positive on ER, PR, and HER2. The majority of malignant cases were of grade II which accounted for 29 (10.9%) samples, followed by 23 (8.6%) with grade III. The association between age and grade was statistically not significant (p=0.113). However, the association between age and B categories was statistically significant with a p-value of 0.0002. A significantly higher proportion of cases with B5a (malignant-in situ carcinoma) or B5b (malignant-invasive carcinoma) categories were in the age range of 31-35 years and 36-40 years.

CONCLUSION

Breast cancer is rare among younger women. It mostly occurs in women over the age of 40 years. In women under the age of 40, it usually presents as a self-detected palpable mass and can show various radiological findings in accordance with the histological grade. Ultrasonography is the main method for the diagnosis of breast cancer especially in younger women, whereas mammography and MRI can contribute to both diagnosis and assessment of the extent of the disease.

Real-World Diagnostic Accuracy of the On-Site Cytopathology Advance Report (OSCAR) Procedure Performed in a Multidisciplinary One-Stop Breast Clinic

Fine-needle aspiration (FNA) cytology has been widely used for the diagnosis of breast cancer lesions with the objective of differentiating benign from malignant masses. However, the occurrence of unsatisfactory samples and false-negative rates remains a matter of concern. Major improvements have been made thanks to the implementation of rapid on-site evaluation (ROSE) in multidisciplinary and integrated medical settings such as one-stop clinics (OSCs). In these settings, clinical and radiological examinations are combined with a morphological study performed by interventional pathologists. The aim of our study was to assess the diagnostic accuracy of the on-site cytopathology advance report (OSCAR) procedure on breast FNA cytologic samples in our breast OSC during the first three years (April 2004 till March 2007) of its implementation. To this goal, we retrospectively analyzed a series of 1820 breast masses (1740 patients) radiologically classified according to the American College of Radiology (ACR) BI-RADS lexicon (67.6% being either BI-RADS 4 or 5), sampled by FNA and immediately diagnosed by cytomorphology. The clinicoradiological, cytomorphological, and histological characteristics of all consecutive patients were retrieved from the hospital computerized medical records prospectively registered in the central information system. Histopathological analysis and ultrasound (US) follow-up (FU) were the reference diagnostic tests of the study design. In brief, we carried out either a histopathological verification or an 18-month US evaluation when a benign cytology was concordant with the components of the triple test. Overall, histology was available for 1138 masses, whereas 491 masses were analyzed at the 18-month US-FU. FNA specimens were morphologically nondiagnostic in 3.1%, false negatives were observed in 1.5%, and there was only one false positive (0.06%). The breast cancer prevalence was 62%. Diagnostic accuracy measures of the OSCAR procedure with their 95% confidence intervals (95% CI) were the following: sensitivity (Se) = 97.4% (96.19-98.31); specificity (Sp) = 94.98% (92.94-96.56); positive predictive value (PPV) = 96.80% (95.48-97.81); negative predictive value (NPV) = 95.91% (94.02-97.33); positive likelihood ratio (LR+) = 19.39 (13.75-27.32); negative predictive ratio (LR-) = 0.03 (0.02-0.04), and; accuracy = 96.45% (95.42-97.31). The respective positive likelihood ratio (LR+) for each of the four categories of cytopathological diagnoses (with their 95% CI) which are malignant, suspicious, benign, and nondiagnostic were 540 (76-3827); 2.69 (1.8-3.96); 0.03 (0.02-0.04); and 0.37 (0.2-0.66), respectively. In conclusion, our study demonstrates that the OSCAR procedure is a highly reliable diagnostic approach and a perfect test to select patients requiring core-needle biopsy (CNB) when performed by interventional cytopathologists in a multidisciplinary and integrated OSC setting. Besides drastically limiting the rate of nondiagnostic specimens and diagnostic turn-around time, OSCAR is an efficient and powerful first-line diagnostic approach for patient-centered care.

A Look at the Other Side: High-Risk Lesions and Occult Contralateral Malignancy in Symmetry Procedures for Patients Undergoing Oncoplastic Breast-Conserving Surgery

BACKGROUND

The incidence of occult breast cancer among patients undergoing reduction mammoplasty or risk-reducing mastectomies ranges from 1% to approximately 10%, respectively. Identification of incidental cancer often mandates subsequent mastectomy due to ambiguous margins. This study aimed to determine the incidence of contralateral malignancy among patients undergoing oncoplastic breast-conserving surgery (OBCS) with concurrent symmetry procedures.

METHODS

The authors reviewed their prospectively maintained institutional database of patients with unilateral breast cancer who underwent OBCS. Patients who underwent excisional biopsy on the contralateral breast were analyzed separately. Patient demographics, pathologic features, and subsequent disease management were evaluated.

RESULTS

Between March 2018 and July 2022, 289 patients underwent OBCS with a symmetry procedure, and 100 patients yielded contralateral breast tissue specimens. For 14 patients, a planned excisional biopsy was performed with their symmetry procedure, and five lesions (36%) were found to be malignant. Of the remaining 86 patients, 92% underwent preoperative breast magnetic resonance imaging (MRI). Four patients (4.7%) had occult malignancies identified on the contralateral breast pathology; three patients with ductal carcinoma in situ and one patient with invasive lobular carcinoma. Three patients had undergone preoperative MRI without suspicious findings. No patients required mastectomy for treatment of the contralateral breast cancer.

CONCLUSION

The incidence of occult malignancy among OBCS symmetry procedures approaches 5%. The final pathology of excisional biopsies had a higher upgrade rate than previously reported. All identified malignancies were early-stage disease. The higher incidence of occult breast cancer in this population warrants the routine orientation of all specimens, which allows patients with incidental early-stage cancer the option of breast preservation.

Imaging Characteristics of and Multidisciplinary Management Considerations for Atypical Ductal Hyperplasia and Flat Epithelial Atypia: Review of Current Literature

High-risk lesions of the breast are frequently encountered in percutaneous biopsy specimens. While benign, these lesions have historically undergone surgical excision due to their potential to be upgraded to malignancy. However, there is emerging evidence that a tailored management approach should be considered to reduce overtreatment of these lesions. Flat epithelial atypia (FEA) and atypical ductal hyperplasia (ADH) are two of the most commonly encountered high-risk lesions. FEA has been shown to have a relatively low rate of progression to malignancy, and some guidelines are now recommending observation over routine excision in select cases. Selective observation may be reasonable in cases where the target lesion is small and completely removed at biopsy and when there are no underlying risk factors, such as a history of breast cancer or genetic mutation or concurrent ADH. ADH has the highest potential upgrade rate to malignancy of all the high-risk lesions. Most society guidelines continue to recommend surgical excision of this lesion. More recently, some literature suggests that ADH lesions that appear completely removed at biopsy, involve limited foci (less than two or three) with no necrosis or significant atypia, manifest as a small group of mammographic calcifications, or demonstrate no enhancement at MRI may be reasonable for observation. Ultimately, management of all high-risk lesions must be based on a multidisciplinary approach that considers all patient, radiologic, clinical, and histopathologic factors. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Implementation of vacuum-assisted excision as a management option for benign and high-risk breast lesions

OBJECTIVE

Previous studies have shown that vacuum-assisted excision (VAE) is a safe and effective alternative for surgical excision (SE) of benign breast lesions. However, the use of VAE in high-risk lesions is controversial and guidelines are ambiguous. This study describes the impact of the implementation of VAE in terms of management and outcomes compared to a cohort before implementation.

METHODS

A single centre retrospective study with two cohorts: 'before' and 'after' implementation of VAE was performed. All patients with a benign or high-risk lesion treated by VAE or SE between 2016 and 2019 were included. Excision, complication, and upgrade rates were compared between both cohorts. Cox regression was used for the evaluation of recurrences and re-excisions.

RESULTS

The overall excision rate of all benign and high-risk lesions was comparable in both cohorts (17% vs 16%, p = 0.700). After implementation, benign lesions were significantly more often managed by VAE (101/151, 67%, p < 0.001). Re-excision, recurrence, and complication rates were low and comparable between cohorts (4.3% vs 3.9%, p > 0.999; 3.0 vs 2.0%, p = 0.683; 3.4 vs 6.6%, p = 0.289, respectively).

CONCLUSION

SE could safely be replaced by VAE in 58% of patients treated for a benign or high-risk lesion. With this shift in management, the use of operating rooms and general anaesthesia can safely be omitted in this patient group. Further research on high-risk lesions is warranted since our data are exploratory.

ADVANCES IN KNOWLEDGE

This study provides supportive data for the use of VAE as a management option for both benign (up to 5 cm) and high-risk lesions. Outcomes on re-excision, recurrence should be confirmed in prospective studies especially in high-risk lesions.

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

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

High-Risk Breast Lesions Diagnosed by Ultrasound-Guided Vacuum-Assisted Excision

PURPOSE

The aim of this study was to analyze the role of ultrasound-guided vacuum-assisted excision (US-guided VAE) in the treatment of high-risk breast lesions and to evaluate the clinical and US features of the patients associated with recurrence or development of malignancy.

MATERIALS AND METHODS

Between April 2010 and September 2021, 73 lesions of 73 patients underwent US-guided VAE and were diagnosed with high-risk breast lesions. The incidence of recurrence or development of malignancy for high-risk breast lesions was evaluated at follow-up period. The clinical and US features of the patients were analyzed to identify the factors affecting the recurrence or development of malignancy rate.

RESULTS

Only benign phyllodes tumors on US-guided VAE showed recurrences, while other high-risk breast lesions that were atypical ductal hyperplasia (ADH), lobular neoplasia (atypical lobular hyperplasia/lobular carcinoma in situ), radial scar, and flat epithelial atypia did not show recurrences or malignant transformation. The recurrence rate of the benign phyllodes tumor was 20.8% (5/24) in a mean follow-up period of 34.3 months. The recurrence rate of benign phyllodes tumor with distance from nipple of less than 1 cm was significantly higher than that of lesions with distance from nipple of more than 1 cm (75% vs. 10%, p < 0.05).

CONCLUSIONS

Benign phyllodes tumors without concurrent breast cancer could be safely followed up instead of surgical excision after US-guided VAE when the lesions were classified as BI-RADS 3 or 4A by US.

Safety of de-escalation of surgical intervention for atypical ductal hyperplasia on percutaneous biopsy: One size does not fit all

BACKGROUND

Oncologic safety of active monitoring (AM) for atypical ductal hyperplasia (ADH) on core-needle biopsy (CNB) is not well defined. We sought to define oncologic outcomes for AM to manage ADH meeting institutional predefined low-risk criteria (LOW).

METHODS

ADH was diagnosed on CNB from 10/2015-03/2020. LOW (pure ADH, size <1 cm, >50% removed by CNB, <3 foci, and no necrosis) patients were offered AM; all others were recommended for surgical excision. Oncologic outcomes were compared for AM and surgery.

RESULTS

111 were included, 21 (19%) meeting LOW. AM occurred in 18 (86%) while 3 elected for excision (with 0% upgrade). Of the 18 LOW in AM, 2 required additional CNB (none at ADH site): 0% were diagnosed with cancer over median 23 month follow-up.

CONCLUSIONS

There were no missed cancers at ADH site during AM for LOW, confirming the oncologic safety of AM in this select group.

Management of Lobular Neoplasia Diagnosed by Core Biopsy

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

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

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

High-risk breast lesions: role of multi-parametric DCE-MRI in detection and histopathological upgrade prediction

Background

High-risk breast lesions represent 3–21% of all breast lesions and are non-obligate precursors of malignancy. Various studies have evaluated the value of DCE-MRI including DWI and ADC mapping in the detection of high-risk breast lesions, differentiating them from malignant lesions and predicting upgrade risk after surgical excision reducing misdiagnosis and overtreatment. This study is a retrospective review of all image-guided breast biopsy procedures performed in 2021 at our institution, identified 68 patients with histopathologically proven high-risk breast and available MRI examinations with no concurrent ipsilateral malignancy. Image analysis of MRI examinations included morphological criteria, enhancement pattern, dynamic curves, DWI and ADC mapping assessment. Since our knowledge of high-risk breast lesions is still growing, this study is important to evaluate the merits of DCE-MRI in the assessment of high-risk breast lesions, to allow optimization of treatment, better limit it to those women at risk, and avoid overtreatment in women at low risk.

Results

The mean ADC value of high-risk breast lesions was not significantly different from that of malignant breast lesions (p value = 0.015). Non-mass enhancement and type III enhancing curve proved to be significant indicators of high-risk breast lesions upgrade in surgical pathology. Cut-off average ADC value for differentiating upgraded high-risk lesions from non-upgraded high-risk lesions proved 1.24 mm2/sec with sensitivity and specificity of 94 & 100%, respectively.

Discussion

Management of high-risk breast lesions is important in the screening setting, as they are non-obligate precursors of malignancy, and also function as risk indicators. Frequency and upgrade rates of high-risk lesions detected by MRI provide a reference for clinical management. DCE-MRI has a high negative predictive value in predicting the upgrade risk of high-risk lesions. In this study, non-mass enhancement and type III curve were proven to be indicators of high-risk lesion upgrade. Limitations of the study included small number of patients and limited follow-up period.

Conclusions

The use of multi-parametric DCE-MRI including DWI and ADC mapping provides complementary information to detect high-risk breast lesions and predict their upgrade rate.

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

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

Upgrade Rates of Intraductal Papilloma with and without Atypia Diagnosed on Core Needle Biopsy and Clinicopathologic Predictors

Surgical excision of breast intraductal papilloma (IDP) without atypia diagnosed on core needle biopsy (CNB) is controversial as the risk of upgrade to malignant lesions is not well established. This study investigates upgrade rates of benign and atypical IDP to ductal carcinoma in situ (DCIS) and invasive carcinoma (IC) and clinicopathologic predictors. We identified 556 cases of IDP diagnosed on CNB at a single institution from 2010-2020 after excluding patients with a history of breast carcinoma, ipsilateral high-risk lesion, radiologic/pathologic discordance, or less than 2 years of follow-up if no excision within one year. Of these, 97 biopsies were consistent with atypical IDP and 459 were benign IDP. Surgical excision was performed for 318 (57.2%), and the remaining 238 (42.8%) underwent active monitoring. The upgrade rate for IDP without atypia was 2/225 (0.9%; 1 DCIS and 1 IC). Of 93 surgically excised atypical IDPs, 19/93 (20.4%) upgraded (14 DCIS and 5 IC). Of 238 non-excised IDPs followed clinically (range 24-140 months, mean 60 months), there was no subsequent breast cancer diagnosed at the IDP site on follow-up. Mean age of patients was 56 yr±12.6sd without upgrade, 63 yr±10.6sd (p value=0.027) with DCIS, and 61 yr±10.8sd (p value=0.35) with IC. Atypical IDP was more likely to upgrade if biopsied by stereotactic guidance (8/19, 42.1% p=0.035). At our institution, we had an exceedingly low upgrade rate for benign IDP. Overall, patients with upgrade to DCIS were older. For atypical IDP, upgrade was seen in higher proportions of stereotactic biopsies.

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

INTRODUCTION

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

METHODS

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

OUTCOMES

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

RESULTS

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

CONCLUSION

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

Atypical Ductal Hyperplasia-Ductal Carcinoma In Situ Spectrum: Diagnostic Considerations and Treatment Impact in the Era of Deescalation

As the first node in treatment algorithms for breast disease, pathologists have the potential to play a critical role in refining appropriate therapy for lesions in the atypical ducal hyperplasia-ductal carcinoma in situ (ADH-DCIS) spectrum by conservatively approaching diagnosis of lesions limited in size on core needle biopsy. Appropriate efforts to downgrade the diagnosis of lesions at the borderline of ADH and DCIS will certainly lead to more breast conservation and avoid the common morbidities of mastectomy, sentinel node biopsy, and radiation therapy. Whether results of clinical trials of active surveillance will successfully identify a subset of women who may successfully forgo even limited breast-conserving surgery is eagerly anticipated. Given the increasing concern that a significant number of women with DCIS are overtreated, identification of patients at very low risk for progression who may forgo surgery and radiation therapy safely is of significant interest.

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

CONTEXT

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Underestimation Rate in the Percutaneous Diagnosis of Radial Scar/Complex Sclerosing Lesion of the Breast: Systematic Review

OBJECTIVE

 To evaluate the underestimation rate in breast surgical biopsy after the diagnosis of radial scar/complex sclerosing lesion through percutaneous biopsy.

DATA SOURCES

 A systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. The PubM: ed, SciELO, Cochrane, and Embase databases were consulted, with searches conducted through November 2020, using specific keywords (radial scar OR: complex sclerosing lesion, breast cancer, anatomopathological percutaneous biopsy AND/OR: surgical biopsy).

DATA COLLECTION

 Study selection was conducted by two researchers experienced in preparing systematic reviews. The eight selected articles were fully read, and a comparative analysis was performed.

STUDY SELECTION

 A total of 584 studies was extracted, 8 of which were selected. One of them included women who had undergone a percutaneous biopsy with a histological diagnosis of radial scar/complex sclerosing lesion and subsequently underwent surgical excision; the results were used to assess the underestimation rate of atypical and malignant lesions.

DATA SYNTHESIS

 The overall underestimation rate in the 8 studies ranged from 1.3 to 40% and the invasive lesion underestimation rate varied from 0 to 10.5%.

CONCLUSION

 The histopathological diagnosis of a radial scar/complex sclerosing lesion on the breast is not definitive, and it may underestimate atypical and malignant lesions, which require a different treatment, making surgical excision an important step in diagnostic evaluation.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

Surgical delay was not associated with an increased UR.

Role of breast MRI in predicting histologic upgrade risks in high-risk breast lesions: A review

PURPOSE

This article reviews the frequency, upgrade rate and valuable imaging characteristics for predicting the histologic upgrade risks of high-risk lesions on MRI, so as to provide a reference for the management of the lesions.

METHODS

A comprehensive search for relevant publications from January 2011 to January 2021 was conducted in the PubMed database. The frequency, upgrade rate and valuable imaging characteristics for predicting the upgrade risks of high-risk lesions on MRI included in the articles were reviewed, and the management of high-risk lesions was provided with a reference according to the review results.

RESULTS AND CONCLUSIONS

In terms of management options, Atypical ductal hyperplasia (ADH) and Lobular neoplasia (LN) (the top two high-risk lesions with the highest upgrade rate and frequency) were treated with surgical resection. However, the final treatment decision for other high-risk lesions should be made by a multidisciplinary committee. In terms of the value of breast MRI in predicting the upgrade risks of high-risk lesions, the lesions that were confirmed to upgrade after surgery showed some enhancement characteristics, especially for ADH and LN. At the same time, Dynamic contrast-enhanced MRI (DCE-MRI) has a high negative predictive value (NPV) in predicting the upgrade risks of the high-risk lesions, hence misdiagnosis and overtreatment can be reduced. Diffusion-weighted imaging (DWI) and relative apparent diffusion coefficient (rADC) can be used to predict the upgrade risks of the lesions, and the ADC of upgraded lesions is lower than that of non-upgraded lesions. However, these conclusions should be confirmed by further studies.

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

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

Flat epithelial atypia: What the radiologist needs to know in 2021

The World Health Organization defines flat epithelial atypia (FEA), as a "presumably neoplastic intraductal alteration characterized by the replacement of native epithelial cells by a single layer or three to five layers of mildly atypical cells.". In this article, we will review FEA and compare its characteristics and differences with other atypical high-risk breast lesions. In addition, the imaging appearance of FEA will be described. Finally, we will discuss current outcomes and provide an update on its management based on the last recommendations.

Atypical ductal hyperplasia on core needle biopsy: Surgical outcomes of 200 consecutive cases from a high-volume breast program

Atypical ductal hyperplasia (ADH) is an indication for excisional biopsy to rule out occult breast cancer. We analyzed pathological findings on excisional biopsy for ADH diagnosed in a high volume breast center equipped with digital tomosynthesis. Two hundred consecutive patients were diagnosed with ADH on core biopsy with radiographic concordance followed by excisional biopsy. On excisional biopsy, 33 patients (16.5%) were diagnosed with DCIS or invasive breast cancer. Patients with a concurrent diagnosis of papilloma had a higher risk of upstaging on both univariate and multivariate analysis (41.7% vs. 14.9%, p=0.015). No other statistically significant predictors of upgrading were identified (p>0.05).

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

Purpose

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

Materials and Methods

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

Results

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

Conclusion

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

Precision pathology as applied to breast core needle biopsy evaluation: implications for management

With the shift to de-escalation of therapy for some breast cancers and fewer surgical excisions for high-risk lesions identified on breast imaging studies at one end of the spectrum, and the greater use of neoadjuvant systemic therapy at the other end, pathologists are ever more critical in guiding management decisions for women with breast disease following core needle biopsy. One important consequence of this shift in management paradigms is the elimination of the opportunity for a "second-look" with the excision specimen to confirm or refine the diagnosis rendered on core needle biopsy. Thus, not only is there the imperative for accuracy and precision of core needle biopsy diagnoses, increasingly it is the only opportunity for that diagnosis.

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

BACKGROUND

The management of high-risk breast lesions diagnosed on image-guided core biopsy remains controversial. We implemented a high-risk breast conference attended by breast pathologists, imagers, and surgeons to prospectively review all contemporary cases in order to provide a consensus recommendation to either surgically excise or follow on imaging at 6-month intervals for a minimum of 2 years.

METHODS

Between May, 2015 and June, 2019, 127 high-risk lesions were discussed. Of these 127 cases, 116 had concordant radiology-pathology (rad-path) findings. The remaining 11 patients had discordant rad-path findings. Of the 116 concordant cases, 6 were excluded due to lack of the first imaging follow-up until analysis. Of the remaining 110 patients, 43 had atypical ductal hyperplasia (ADH), 12 had lobular carcinoma in situ (LCIS), 19 had atypical lobular hyperplasia (ALH), 33 had radial scar (RS), 2 had flat epithelial atypia (FEA), and 1 had mucocele-like lesion (ML). We recommended excision for ADH if there were > 2 ADH foci or < 90% of the associated calcifications were removed. For patients with LCIS or ALH, we recommended excision if the LCIS or ALH was associated with microcalcifications or the LCIS was extensive. We recommended excision of RS when < 1/2 of the lesion was biopsied. We recommended all patients with FEA and ML for 6-month follow-up.

RESULTS

Following conference-derived consensus for excision, of the 27 ADH excised, 9 were upgraded to invasive carcinoma or ductal carcinoma in situ. Of the six LCIS cases recommended for excision, none were upgraded. Nine excised radial scars revealed no upgrades. Additionally, 3 patients with ADH, 2 with ALH, 1 with LCIS, and 2 with RS underwent voluntary excision, and none were upgraded. All other patients (13 with ADH, 5 LCIS, 17 ALH, 22 RS, 2 FEA and 1 ML) were followed with imaging, and none revealed evidence of disease progression during follow-up (187-1389 days). All 11 rad-path discordant cases were excised with 2 upgraded to carcinoma.

CONCLUSIONS

The results of this prospective study indicate that high-risk breast lesions can be successfully triaged to surgery versus observation following establishment of predefined firm guidelines and performance of rigorous rad-path correlation.

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

PURPOSE

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

METHODS

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

RESULTS

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

Prospective Multicenter Study Validate a Prediction Model for Surgery Uptake Among Women with Atypical Breast Lesions

BACKGROUND

Diagnosis of atypical breast lesions (ABLs) leads to unnecessary surgery in 75-90% of women. We have previously developed a model including age, complete radiological target excision after biopsy, and focus size that predicts the probability of cancer at surgery. The present study aimed to validate this model in a prospective multicenter setting.

- METHODS

Women with a recently diagnosed ABL on image-guided biopsy were recruited in 18 centers, before wire-guided localized excisional lumpectomy. Primary outcome was the negative predictive value (NPV) of the model.

RESULTS

The NOMAT model could be used in 287 of the 300 patients included (195 with ADH). At surgery, 12 invasive (all grade 1), and 43 in situ carcinomas were identified (all ABL: 55/287, 19%; ADH only: 49/195, 25%). The area under the receiving operating characteristics curve of the model was 0.64 (95% CI 0.58-0.69) for all ABL, and 0.63 for ADH only (95% CI 0.56-0.70). For the pre-specified threshold of 20% predicted probability of cancer, NPV was 82% (77-87%) for all ABL, and 77% (95% CI 71-83%) for patients with ADH. At a 10% threshold, NPV was 89% (84-94%) for all ABL, and 85% (95% CI 78--92%) for the ADH. At this threshold, 58% of the whole ABL population (and 54% of ADH patients) could have avoided surgery with only 2 missed invasive cancers.

CONCLUSION

The NOMAT model could be useful to avoid unnecessary surgery among women with ABL, including for patients with ADH.

CLINICAL TRIAL REGISTRATION

NCT02523612.

Benign breast papillomas without atypia diagnosed with core needle biopsy: Outcome of surgical excision and imaging follow-up

PURPOSE

To evaluate the surgical upgrade rate to malignancy and high-risk lesions in cases of papilloma without atypia diagnosed with imaging-guided percutaneous core needle biopsy (CNB) and to determine whether any lesion imaging features, biopsy techniques, and pathological factors can predict lesion upgrade to help guide clinical management.

MATERIALS AND METHODS

Benign papillomas without atypia (n = 399) diagnosed with CNB were retrospectively reviewed. The surgical upgrade rate to malignancy or high-risk lesion (atypical ductal hyperplasia, atypical lobular hyperplasia, lobular carcinoma in-situ, flat epithelial atypia and atypical papilloma) was determined. Detection modality (i.e. mammography, ultrasonography (US), magnetic resonance imaging (MRI)), lesion type and size, biopsy-guidance modality (US, stereotactic, MRI), biopsy needle size (<14 G vs ≥14 G), use of vacuum assistance, and presenting symptoms were statistically analyzed. The reference standard for evaluation of upgrade was either excision or at least 24 months of imaging follow-up. Chi Square test and Fisher exact tests were performed for categorical variables, and the Mann-Whitney-U test was used for continuous variables.

RESULTS

Ultrasound was the predominant biopsy modality (78.4 %, p < 0.001). Of the 399 benign papilloma lesions in 329 women, 239 (59.9 %) were excised and 93 others were followed for at least 24 months (total of 332). Of these 332 lesions, 7 (2.1 %) were upgraded to ductal carcinoma in-situ and 41 (12.3 %) to high-risk lesions at excision. Larger lesion size (≥15 mm, p = 0.009), smaller biopsy needle size (≥14 G, p = 0.027), and use of spring-loaded biopsy device (p = 0.012) were significantly associated with upgrade to atypia. Only lesion size (≥15 mm, p = 0.02) was associated with upgrade to cancer.

CONCLUSION

Upgrade to malignancy of biopsy-proven benign papillomas without atypia at the time of surgery was sufficiently low (2.1 %) to support non-operative management. Surgery may be performed for selected cases- those with larger lesion size and those whose biopsies were performed with smaller spring-loaded biopsy needles.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Development and Prospective Validation of a Risk Calculator That Predicts a Low Risk Cohort for Atypical Ductal Hyperplasia Upstaging to Malignancy: Evidence for a Watch and Wait Strategy of a High-Risk Lesion

BACKGROUND

Guidelines recommend surgical excision of atypical ductal hyperplasia (ADH) due to the concern of undersampling a potential malignancy on core needle biopsy (CNB). The purpose of this study was to determine clinical, radiological and pathological variables associated with ADH upstaging to cancer and to develop a predictive risk calculator capable of identifying women who have a low oncological risk of upstaging.

METHODS

A prospectively collected database from a tertiary breast referral center was analyzed for women diagnosed with ADH on CNB between January 2013 to December 2017 who underwent surgical excision. CNB and surgical pathology reports were examined to determine rate of upstaging. The association between clinical, radiological and pathological variables were evaluated using regression analysis to determine predictors of ADH upstaging to cancer. Significant variables (p ≤ 0.05) identified on univariate analysis were assigned a score of "1" and were included in the ADH upstaging risk calculator.

RESULTS

A total of 1986 patients underwent surgery for a high-risk lesion. We identified 318 (16.0%) patients who had ADH identified on their CNB who underwent surgery-of which 290 were included in our study. The upstage rate was 24.8%. Five variables were associated with upstaging and included in our calculator: (1) lesion > 5 mm on ultrasound; (2) lesion > 5 mm on mammogram; (3) one or more "high-risk" lesion(s) on CNB; (4) pathological suspicion for cancer and; (5) incomplete removal of calcifications on CNB. Patients with a score of 0 had a 2% risk of being upstaged to cancer and were deemed low risk with 17.2% of patients falling within this category.

CONCLUSIONS

Patients with ADH on CNB can be stratified into a low oncological cohort who have a 2% risk of being upstaged to carcinoma. In the future, these select patients may be counselled and potentially offered observation as an alternative to surgery.

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.

Is radial scar on core needle biopsy a risk factor for malignancy? A single-center retrospective review and implications for management

INTRODUCTION

Reported upgrade rate to malignancy of radial scars (RS) ranges widely (0%-40%) making management controversial.

METHODS

A retrospective chart review was performed on patients with RS on core needle biopsy (CNB). Upgrade rates to malignancy and atypia on surgical excision were evaluated.

RESULTS

Of 127 patients with RS on CNB, 53 were excluded due to malignancy or missing records. Of 74 patients reviewed, 52 (70.3%) had surgical excision with four (7.7%) upgraded to malignancy. Eight patients (10.8%) had atypia with RS on CNB with two (25%) upgraded to malignancy. When isolated RS was on CNB, 2 of 44 (4.5%) upgraded to malignancy while 15 of 44 (34%) had atypia on excision. Of 22 patients (29.7%) who did not have excision, zero developed cancer.

CONCLUSION

We found higher than expected upgrade rates of isolated RS to atypia which can alter management. Additionally, 25% of RS with atypia upgraded to malignancy suggesting these patients are at higher risk.

Pitfalls and controversies in pathology impacting breast cancer management

Introduction: Breast cancer is a heterogeneous disease, at morphological, molecular, and clinical levels and this has significant implications for the diagnosis and management of the disease. The introduction of breast screening, and the use of small tissue sampling for diagnosis, the recognition of new morphological and molecular subtypes, and the increasing use of neoadjuvant therapies have created challenges in pathological diagnosis and classification.Areas covered: Areas of potential difficulty include columnar cell lesions, particularly flat epithelial atypia, atypical ductal hyperplasia, lobular neoplasia and its variants, and a range of papillary lesions. Fibroepithelial, sclerosing, mucinous, and apocrine lesions are also considered. Established and newer prognostic and predictive markers, such as immune infiltrates, PD-1 and PD-L1 and gene expression assays are evaluated. The unique challenges of pathology assessment post-neoadjuvant systemic therapy are also explored.Expert opinion: Controversies in clinical management arise due to incomplete and sometimes conflicting data on clinicopathological associations, prognosis, and outcome. The review will address some of these challenges.

Imaging Follow-up Versus Surgical Excision for Radial Scars Identified on Tomosynthesis-Guided Core Needle Biopsy

RATIONALE AND OBJECTIVES

We investigated if imaging or pathology features could determine when imaging follow-up is appropriate after diagnosis of radial scar on digital breast tomosynthesis (DBT)-guided core needle biopsy (CNB).

MATERIALS AND METHODS

We conducted a retrospective review of all patients diagnosed with radial scars on DBT-guided CNB at our institution between November 2014 and December 2016. Cases were excluded if DCIS or invasive malignancy was present in the same core specimens. Patient age; needle size; number of cores; visibility on full-field digital mammography versus DBT; lesion size; presence of architectural distortion, mass, or calcifications; imaging stability; presence or absence of atypia; length of imaging follow-up, and excisional pathology were collected.

RESULTS

Of 45 eligible biopsies, 6 cases had radial scars with associated atypia and 39 cases had no associated atypia. Twenty-four patients underwent surgical excision, including all patients with atypia on CNB. One case (4%) was upstaged to DCIS on surgical excision after CNB revealed a radial scar with associated ADH. There was also a case without atypia on CNB, but excisional pathology revealed associated ADH. In cases with radial scars and associated atypia on CNB, the upstage rate was 17%. In cases without atypia on CNB that underwent surgical excision, the upstage rate was 0%. Imaging follow-up was available in 13 patients who did not undergo surgical excision, with stability in all 13 with a median follow-up of 18 months.

CONCLUSION

Annual imaging follow-up appears reasonable in selected patients with radial scars but no atypia on DBT-guided CNB.

Atypical Ductal Hyperplasia and Those Bordering on Ductal Carcinoma In Situ Should Be Included in the Active Surveillance Clinical Trials

OBJECTIVES

Women with atypical ductal hyperplasia (ADH), unlike those with ductal carcinoma in situ (DCIS), are denied eligibility for active surveillance clinical trials.

METHODS

We applied the inclusion criteria of the Comparison of Operative to Monitoring and Endocrine Therapy (COMET) trial to the cases of women (n = 165) at the Roswell Park Cancer Institute who had a diagnosis of ADH, ADH bordering on DCIS, or low- to intermediate-grade DCIS on core biopsy taken during screening mammography. Upgrade of lesions to high risk was based on invasive carcinoma, high-grade DCIS, or DCIS with comedo necrosis.

RESULTS

In total, nine (5.5%) lesions were upgraded: two (1.7%) reported ADH, one (5.9%) reported ADH bordering on DCIS, and six (19.4%) reported DCIS (P = .002); and two (1.6%) reclassified ADH vs seven (17.1%) reclassified DCIS (P < .001). In multivariate analysis, only increased number of foci had the potential to predict high risk (odds ratio: 1.39; P = .06).

CONCLUSIONS

We conclude that ADH and ADH bordering on DCIS have lower upgrade rates than DCIS. We recommend opening an active surveillance clinical trial for women with these diagnoses.

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.

Prediction of Atypical Ductal Hyperplasia Upgrades Through a Machine Learning Approach to Reduce Unnecessary Surgical Excisions

PURPOSE

Surgical excision is currently recommended for all occurrences of atypical ductal hyperplasia (ADH) found on core needle biopsies for malignancy diagnoses and treatment of lesions. The excision of all ADH lesions may lead to overtreatment, which results in invasive surgeries for benign lesions in many women. A machine learning method to predict ADH upgrade may help clinicians and patients decide whether combined active surveillance and hormonal therapy is a reasonable alternative to surgical excision.

METHODS

The following six machine learning models were developed to predict ADH upgrade from core needle biopsy: gradient-boosting trees, random forest, radial support vector machine (SVM), weighted K-nearest neighbors (KNN), logistic elastic net, and logistic regression. The study cohort consisted of 128 lesions from 124 women at a tertiary academic care center in New Hampshire who had ADH on core needle biopsy and who underwent an associated surgical excision from 2011 to 2017.

RESULTS

The best-performing models were gradient-boosting trees (area under the curve [AUC], 68%; accuracy, 78%) and random forest (AUC, 67%; accuracy, 77%). The top five most important features that determined ADH upgrade were age at biopsy, lesion size, number of biopsies, needle gauge, and personal and family history of breast cancer. Using the random forest model, 98% of all malignancies would have been diagnosed through surgical biopsies, whereas 16% of unnecessary surgeries on benign lesions could have been avoided (ie, 87% sensitivity at 45% specificity).

CONCLUSION

These results add to the growing body of support for machine learning models as useful aids for clinicians and patients in decisions about the clinical management of ADH.