Malignant upgrade rate and associated clinicopathologic predictors for concordant intraductal papilloma without atypia: A systematic review and meta-analysis

Previously reported upgrade rates for benign breast intraductal papilloma (IDP) are widely variable. However, many previous studies have failed to consider radiologic-pathologic discordance of lesions. This review aims to synthesize malignant upgrade data for benign, concordant IDP at surgical excision. Thirteen studies were included in our meta-analysis. The pooled estimate for percentage underestimation of carcinoma was 1.4% (95% CI: 0.8%-2.0%). We conclude that these lesions can be safely managed by active surveillance.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Treatment Strategy for Breast Benign Intraductal Papilloma: A Meta-Analysis

Currently, the optimal treatment approach for breast benign intraductal papilloma (IDP) diagnosed via biopsy remains uncertain. There is ongoing debate regarding the feasibility of clinical follow-up and the criteria for selective surgical excision. This study aims to conduct a meta-analysis to determine the rate of upgrade from breast benign IDP and identify predictive factors associated with the conversion of benign IDP to high-risk lesions or carcinoma, which could guide healthcare practitioners in selecting the appropriate clinical treatment strategy. We conducted a comprehensive search across multiple databases (PubMed, Web Of Science, Cochrane Library, and Embase) for studies published between 2012 and 2023 that evaluated upgrade rates and predictive factors of breast benign IDP diagnosed via biopsy. In addition, we included studies that reported on the clinical follow-up of patients with breast benign IDP. In total, 32 studies comprising 7371 cases of biopsy-diagnosed breast benign IDP were included. Among these cases, 720 demonstrated an upgrade to high-risk lesions or carcinoma, resulting in an upgrade rate of 6.94% [95% confidence interval (CI): 3.0-8.0%]. A subgroup of 1713 patients was clinically followed up, demonstrating an average follow-up duration of 30.95 months. Among them, 26 cases experienced an upgrade to high-risk lesions or carcinoma, yielding an upgrade rate of 1.51% (95% CI 0.00-2.00). Furthermore, we identified nine predictive factors associated with the upgrading of breast benign IDP, which included age at diagnosis, personal history of breast cancer, family history of breast cancer, multiple IDPs, lesion size ≥ 10 mm, palpable mass, calcification, and the presence of mass and asymmetry in mammographic findings. Although the conversion rate of breast benign IDP to high-risk lesions or carcinoma is relatively low, timely identification of predictive factors associated with benign IDP upgrades may help selecting the optimal clinical treatment strategy, such as surgery for patients with benign IDP presenting one or more predictive factors, while clinical follow-up for those without specific risk factors.

Upgrade Rate and Predictive Factors Associated With Breast Papillary Lesions on Core Biopsy: A Canadian Experience

Background: Papillary lesions of the breast are a heterogeneous group, encompassing a wide range of lesions. The histologic distinction between papillary breast lesions remains challenging, especially on core biopsy specimens. Aim: This study aimed to determine the rate of upgrade to atypia or malignancy of biopsy-proven papillary lesions on surgical follow-up and to assess for factors associated with an upgrade in Greater Vancouver, BC, Canada. Materials and Methods: This is a retrospective population-based study of all breast papillary lesions diagnosed on core biopsy between 2017 and 2019 in the Fraser Health Authority in Greater Vancouver, Canada. Patients were retrieved from the laboratory information system. Patient demographics, histopathologic, and radiologic findings were analyzed. Results: A total of 269 specimens from 269 patients (mean 61.1 years), including 265 female and 4 male patients, were included in the study. Of the 269 specimens, 129 (48%) were intraductal papillomas and 140 (52%) were atypical papillary lesions. The overall upgrade rate among papillomas was 11.6% (15 of 129) on final excision. The mean age of patients diagnosed with papilloma on core biopsy was significantly younger than those with atypical papillary lesions (55.6 vs 66.1 years, P < .0001). Lesion size in patients with papillomas on core biopsy was significantly smaller than those with atypical papillary lesions (11.1 vs 15.1 mm, P = .001). The upgrade rates in patients <55 and ≥55 years were 4.9% and 13.2%. Size (P = .004) and atypia on core biopsy (P = .009) were significantly associated with upgrade. Older age (>55 years) (OR =  5.3, 95% CI: 1.04-27.08) was an independent predictor of upgrade among papillomas. Size, location, and Breast Imaging-Reporting and Data System (BI-RADS) radiologic categories in our study were not associated with predicting the upgrade of papillomas. Conclusion: Our data suggest that the risk of upgrade to atypia or malignancy is sufficient to warrant the excision of benign papillomas of any size in patients aged ≥55 years. In patients younger than 55 years, observation with close clinical and radiological follow-up without surgery may be sufficient. Our findings also support surgical excision of papillomas diagnosed on core biopsy when associated with atypia.

Third International Consensus Conference on lesions of uncertain malignant potential in the breast (B3 lesions)

The heterogeneous group of B3 lesions in the breast harbors lesions with different malignant potential and progression risk. As several studies about B3 lesions have been published since the last Consensus in 2018, the 3rd International Consensus Conference discussed the six most relevant B3 lesions (atypical ductal hyperplasia (ADH), flat epithelial atypia (FEA), classical lobular neoplasia (LN), radial scar (RS), papillary lesions (PL) without atypia, and phyllodes tumors (PT)) and made recommendations for diagnostic and therapeutic approaches. Following a presentation of current data of each B3 lesion, the international and interdisciplinary panel of 33 specialists and key opinion leaders voted on the recommendations for further management after core-needle biopsy (CNB) and vacuum-assisted biopsy (VAB). In case of B3 lesion diagnosis on CNB, OE was recommended in ADH and PT, whereas in the other B3 lesions, vacuum-assisted excision was considered an equivalent alternative to OE. In ADH, most panelists (76%) recommended an open excision (OE) after diagnosis on VAB, whereas observation after a complete VAB-removal on imaging was accepted by 34%. In LN, the majority of the panel (90%) preferred observation following complete VAB-removal. Results were similar in RS (82%), PL (100%), and FEA (100%). In benign PT, a slim majority (55%) also recommended an observation after a complete VAB-removal. VAB with subsequent active surveillance can replace an open surgical intervention for most B3 lesions (RS, FEA, PL, PT, and LN). Compared to previous recommendations, there is an increasing trend to a de-escalating strategy in classical LN. Due to the higher risk of upgrade into malignancy, OE remains the preferred approach after the diagnosis of ADH.

[B3 lesions of the breast: histological, clinical, and epidemiological aspects : Update]

B3 lesions of the breast are a heterogeneous group of lesions with uncertain malignant potential encompassing a broad spectrum of histologically distinct alterations that often pose challenging decisions if diagnosed on the preoperative core or vacuum biopsies. B3 lesions are mostly detected due to mammographic calcifications or mass lesions and, in most cases, encompass a spectrum of atypical lesions such as atypical ductal hyperplasia, classic lobular neoplasia, flat epithelial atypia, papillomas, fibroepithelial tumors, and rarely other lesions such as mucocele-like lesions, atypical apocrine lesions, and rare stromal proliferations. The use of immunohistochemical stains (estrogen receptors, basal cytokeratin, myoepithelial markers, and stromal marker panel) is useful in the differentiation of these lesions and allowing proper classification. Regarding clinical management of B3 lesions, the radiological-pathological correlation of the given entity plays the most important key element for the proper next diagnostic and therapeutic step.

Mucocele-like Lesions of the Breast

Mucocele-like lesions of the breast (MLL) are believed to be due to mucinous ducts extruding their contents into the surrounding stroma. MLLs are a rare entity usually identified by calcifications noted on routine screening mammography. Surgical excision has been recommended due to the propensity for these lesions to harbor atypical ductal hyperplasia (ADH) or malignancy. A 44-year-old female patient presented to the breast center after undergoing routine mammography which showed a group of coarse appearing microcalcifications in the outer third of the breast. After further workup, a core needle biopsy was obtained with pathology showing benign breast tissue with acellular stromal mucin pools containing dystrophic calcifications. The patient underwent surgical excision with final pathology revealing ductal carcinoma in-situ and ADH with prominent mucin production throughout the stroma.

Papillary Lesions of the Breast: Addition of DWI and TIRM Sequences to Routine Breast MRI Could Help in Differentiation Benign from Malignant

AIM

We aimed to investigate the magnetic resonance imaging (MRI) features of benign, atypical or malignant papillary breast lesions and to assess additional value of diffusion-weighted imaging (DWI) and turbo inversion recovery magnitude (TIRM) sequences to routine breast MRI.

BACKGROUND

Differentiation between benign and malignant papillary breast lesions is essential for patient management. However, morphologic features and enhancement patterns of malignant papillary lesions may overlap with those of benign papilloma.

METHODS

Seventy two papillary breast lesions (50 benign, 22 atypical or malignant) were included in the current study, retrospectively. We divided the patients into two groups as benign papillary breast lesions and atypical or malignant papillary breast lesions. Morphologic, dynamic, turbo inversion recovery magnitude (TIRM) values and diffusion features of the papillary lesions were compared between two groups.

RESULTS

Benign papillary lesions were smaller in size (p=0.006 and p=0.005, for radiologist 1 and 2 respectively), closer to areola (p=0.045 and 0.049 for radiologist 1 and 2 respectively) and had higher ADC values (p=0.001 for two radiologists) than atypical or malignant group. ROC curves showed diagnostic accuracy for ADC (AUC=0.770 and 0.762, p<0.0001 for two radiologists) and showed a cut-off value of ≤957 x 10-6 mm2/s (radiologist 1) and ≤ 910 x 10-6 mm2/s (radiologist 2).

CONCLUSION

MRI is a useful method for differentiation between benign and malignant papillary breast lesions. Centrally located, lesser in size and higher ADC values should be considered benign, whereas peripherally located, larger in size and lower ADC values should be considered malignant.

Papillary lesions of the breast

Papillary lesions of the breast represent a heterogeneous group of lesions including benign papillomas, papillomas with focal epithelial atypia, fully fledged ductal carcinoma in situ (DCIS) or lobular neoplasia, papillary DCIS, encapsulated papillary carcinomas without or with invasion, solid papillary carcinomas, and invasive papillary carcinomas. A micropapillary pattern characterized by lack of fibrous stalks within the papillae is observed in micropapillary DCIS and invasive micropapillary carcinoma. In addition, a variety of other rare breast lesions reveals a papillary architecture such as tall cell carcinoma with reversed polarity (TCCRP) and mucinous cystadenocarcinoma, adenomyoepithelioma, and secretory carcinoma. In addition, benign lesions such as usual ductal hyperplasia, apocrine metaplasia, gynecomastia, and juvenile papillomatosis may show a papillary or micropapillary architecture. Fragments of a benign papilloma in a breast biopsy are considered a lesion of uncertain malignant potential (B3 in the European classification) and excision is mostly recommended. Although the knowledge about molecular pathology of papillary breast lesions has increased, there is not sufficient evidence for diagnostically useful molecular features, yet. The aim of this review is to provide an update on papillary and micropapillary lesions with emphasis on problematic areas for daily diagnostic work including biopsies.

Detailed Morphologic Evaluation of Breast Papillary Lesions on Core Biopsy Is Critical for Accurate Classification and Clinical Management: The Experience of an Academic Institute

BACKGROUND

Distinguishing between a breast intraductal papilloma and a papillary lesion with atypia or malignancy can be very challenging on core biopsy. There has been a long ongoing debate over whether or not it is necessary for breast papillary lesions diagnosed on core biopsies to be surgically excised, and the upgrading rate after excision varies.

METHOD AND/OR RESULT

This study was carried out in a subspecialized academic pathology department, with well-formed criteria established among the faculty for the categorization of breast papillary lesions, with emphasis on the morphology evaluation of cellular features. A total of 320 breast core biopsies with follow-up excisions were identified. Of these, 286 cases had concordant results between the biopsy and excision, giving a concordance rate of 89.4%, with 98% concordance (143/146) in benign papilloma, 100% (111/111) in papillary carcinoma, and 51% (32/63) in papilloma with atypia. Of the upgraded cases, two were upgraded from benign to atypical, 11 from atypia to malignancy, and only one from benign to malignant. The overall average upgrading rate was 4.4% (14/320), with the critical upgrading (from benign to atypia or malignancy) rate of 0.94% (3/320). Downgrading was only identified in the group of papilloma with atypia, with 20 of 63 cases downgraded to benign papilloma on excision.

CONCLUSION

Our study indicates that surgical excision may not be necessary for all papillary lesions after detailed evaluation of the morphology on core biopsies. Assessing the morphological features of the epithelial cells is critical for the accurate classification and clinical management of papillary lesions.

Developing Asymmetries without Sonographic Correlate at Digital Breast Tomosynthesis

Background Digital breast tomosynthesis (DBT) has improved the accuracy of mammography, including resolving many breast asymmetries as overlapping breast tissue. The pathologic outcomes of persistent developing asymmetries visualized at DBT are not well established. Purpose To characterize the outcomes and the predictors of malignancy for developing asymmetries visualized at DBT without a sonographic correlate. Materials and Methods This retrospective study included all tomosynthesis-guided biopsies of developing asymmetries performed at a single institution from May 2017 through January 2020. A reader study including three breast imaging radiologists determined interrater agreement and inclusion into the study. Electronic medical records were used to extract patient characteristics, imaging characteristics, and pathologic diagnoses. The Wilcoxon rank sum test, Fisher exact test, and χ² test were used to analyze correlations of patient and imaging characteristics with likelihood of malignancy. Results The reader study included 95 DBT examinations with moderate interrater reliability (Fleiss κ = 0.45). There was majority reader agreement in 85 of the 95 DBT examinations (89%) of 83 women (median age, 56 years; interquartile range, 47-69 years), and this finalized the study data set. At pathologic examination, most asymmetries (68 of 85, 80%) were benign, with common diagnoses being fibrocystic change (n = 20), stromal fibrosis (n = 10), and fat necrosis (n = 10). The overall malignancy rate was 20% (17 of 85 asymmetries; 95% CI: 12, 29); 15 of the 17 malignancies (88%) were invasive cancers. Malignancies were more common in women with a personal history of breast cancer (35% vs 10%, P = .02). Conclusion In 85 developing asymmetries visualized at digital breast tomosynthesis without a sonographic correlate, there was a 20% (95% CI: 12, 29) malignancy rate, which was higher than the rates of malignancy for a developing asymmetry detected at digital mammography. © RSNA, 2021 See also the editorial by Skaane in this issue.

Upgrade Rate and Predictive Factors for Breast Benign Intraductal Papilloma Diagnosed at Biopsy: A Meta-Analysis

BACKGROUND

Current standard management for intraductal papilloma (IDP) diagnosed at biopsy indicates complete surgical resection, but there are increasing controversies over whether and when routine excision is indeed necessary.

OBJECTIVE

The aim of this study was to determine the carcinoma upgrade rate and identify the associated predictive factors for IDP diagnosed at biopsy by meta-analysis.

METHODS

We searched the PubMed and EMBASE databases for studies published from 2009 to 2020 that investigated the upgrade rate and predictive factors of IDP diagnosed at biopsy.

RESULTS

A total of 7016 IDP cases diagnosed at biopsy and histologically examined after surgical excision were pooled from 44 original studies. The pooled prevalence of IDP in breast biopsy findings was 4.6% [95% confidence interval (CI) 4.4-4.7%] and the majority of IDP tumors were benign. The pooled upgrade rates to carcinoma for benign IDP and atypical IDP were 5.0% (95% CI 4.4-5.5%) and 36.0% (95% CI 32.7-39.2%), respectively. In addition, we identified 10 predictive upgrade factors for benign IDP, including Breast Imaging Reporting and Data System (BI-RADS) 5, BI-RADS 4C, mass and calcification in the mammographic finding, bloody nipple discharge, imaging-histological discordance, peripheral IDP, palpable mass, BI-RADS 4B, microcalcification, and lesion size ≥ 1 cm. The upgrade rates associated with these predictive factors ranged from 7.3 to 31.1%.

CONCLUSION

Surgical excision appears a reasonable recommendation for atypical IDP. Patients with benign IDP exhibiting one or more predictive factors might benefit from surgical excision, while patients with asymptomatic benign IDP without these predictive factors can be managed by imaging surveillance.

Tomosynthesis-Guided Vacuum-Assisted Breast Biopsy of Architectural Distortion Without a Sonographic Correlate: A Retrospective Review

BACKGROUND. Digital breast tomosynthesis-guided vacuum-assisted breast biopsy (DBT VAB) allows biopsy of findings seen better or exclusively on digital breast tomosynthesis (DBT), including architectural distortion. Although architectural distortion with an associated sonographic mass correlate has a high risk of malignancy, limited data describe the radiologic-pathologic correlation of tomosynthesis-detected architectural distortion without a sonographic correlate. OBJECTIVE. This study evaluates the malignancy rate of architectural distortions without a sonographic correlate that undergo DBT VAB and provides radiologic-pathologic correlation for benign, high-risk, and malignant entities that are associated with architectural distortion. METHODS. We retrospectively reviewed imaging, as well as pathology slides and/or reports, for DBT VABs performed for architectural distortion without a sonographic correlate at a single institution between June 1, 2017, and January 15, 2020. According to the correlative histopathology, cases were categorized as benign, high risk, or malignant, and specific histopathologic diagnoses were summarized. RESULTS. During the study period, 142 patients (mean age, 59 years) underwent DBT VAB for 151 unique architectural distortions without a sonographic correlate. DBT VAB revealed a malignant diagnosis in 27 (18%), a high-risk lesion in 50 (33%), and a benign diagnosis in 74 (49%). Two cases of atypical ductal hyperplasia were upgraded to malignancy, resulting in a final malignancy rate of 19% (n = 29/151). Most malignant lesions were invasive carcinomas (83%, n = 24/29); most invasive carcinomas were of lobular subtype (54%, n = 13/24). Most high-risk lesions were radial scars/complex sclerosing lesions (62%, n = 31/50). Most benign results represented fibrocystic change (66%, n = 49/74). A subset (11%, n = 8/74) of benign results were considered discordant and subsequently excised, with none representing malignancy. CONCLUSION. The final malignancy rate of 19% in architectural distortion without a sonographic correlate justifies a recommendation for biopsy using DBT VAB. CLINICAL IMPACT. Our results highlight the utility of DBT VAB in the era of DBT. The detailed radiologic-pathologic correlations will assist radiologists in assessing concordance when performing DBT VAB for architectural distortions and provide a reference for future patient management.

Analysis of 612 Benign Papillomas Diagnosed At Core Biopsy: Rate of Upgrade to Malignancy, Factors Associated with Upgrade, and A Proposal For Selective Surgical Excision

Background: Despite numerous published studies, management of benign papillomas without atypia remains controversial. Objective: To determine the malignancy upgrade rate of benign papillomas, identify risk factors for upgrade, and formulate criteria for selective surgery. Methods: This retrospective study included benign papillomas without atypia diagnosed on percutaneous biopsy between 12/01/2000 and 12/31/2019. Papillomas that did not undergo surgical excision or at least 2 years of imaging and/or clinical follow-up were excluded. Clinical, imaging, and histopathologic features were extracted from the electronic medical record. Features associated with upgrade to malignancy were identified. Multivariable logistic regression was performed. Results: The study included 612 benign papillomas in 543 women (mean age 54.5 ± 12.1 years); 466 papillomas were excised, and 146 underwent imaging/clinical surveillance. The upgrade rate to malignancy was 2.3% (14/612). Upgrade rate was associated (p<.05) with radiology-pathology correlation (50.0% if discordant vs 2.1% if concordant), patient age (5.6% for age ≥60 vs 0.7% for age <60), presenting symptoms (6.7% if palpable mass or pathologic nipple discharge vs 1.3% if no symptoms), and lesion size (7.3% if ≥10 mm vs 0.6% if <10 mm). Three of 14 upgraded papillomas were associated with ≥4 metachronous or concurrent peripheral papillomas. No incidental papilloma or papilloma reported as completely excised on core biopsy histopathologic analysis was upgraded. A predictive model combining radiology-pathology discordance, symptoms (palpable mass or nipple discharge), age ≥60, size ≥10 mm, and presence of ≥4 metachronous or concurrent peripheral papillomas achieved AUC 0.91, sensitivity 79%, and specificity 89% for upgrade. Selective surgery based on presence of any of these five factors, while excluding from surgery incidental papillomas and papillomas reported as completely excised on histopathology, would spare 294 of 612 lesions from routine excision, while identifying all 14 upgraded lesions. Conclusion: Benign non-atypical papillomas have a low malignancy upgrade rate; routine surgical excision may not be necessary. Selective excision is recommended for lesions satisfying any of the 5 criteria. Incidental papillomas or papillomas completely excised on histopathology may undergo imaging follow-up. Clinical Impact: The proposed criteria for selective surgery of benign papillomas on core biopsy would reduce surgeries without delaying diagnosis of malignancy.

Papillary neoplasms of the breast including upgrade rates and management of intraductal papilloma without atypia diagnosed at core needle biopsy

Papillary neoplasms of the breast are a heterogeneous group of epithelial tumors nearly entirely composed of papillae. Their classification rests on the characteristics of the epithelium and the presence and distribution of the myoepithelial cells along the papillae and around the tumor. Papillary neoplasms of the breast can be diagnostically challenging, especially if only core needle biopsy (CNB) material is available. This review summarizes salient morphological and immunohistochemical features, clinical presentation, and differential diagnoses of papillary neoplasms of the breast. We include a contemporary appraisal of the upgrade rate to carcinoma (invasive carcinoma and ductal carcinoma in situ [DCIS]) and atypical hyperplasias in surgical excision specimens obtained following CNB diagnosis of papilloma without atypia, and a review of the available follow-up data in cases without immediate surgical excision.

Papillary lesions of the breast: a review

Papillary breast lesions are rare breast tumors that comprise a broad spectrum of diseases. Pathologically they present as mass-like projections attached to the wall of the ducts, supported by fibrovascular stalks lined by epithelial cells. On mammogram they appear as masses that can be associated with microcalcifications. Ultrasound is the most used imaging modality. On ultrasound papillary lesions appear as homogeneous solid lesions or complex intracystic lesions. A nonparallel orientation, an echogenic halo or posterior acoustic enhancement associated with microcalcifications are highly suggestive of malignancy. MRI has proven to be useful to establish the extent of the lesion. Core needle biopsy is the gold standard for diagnosis. Surgical excision is usually recommended, although treatment for papillomas without atypia is still controversial.

Benign Breast Intraductal Papillomas Without Atypia at Core Needle Biopsies: Is Surgical Excision Necessary?

PURPOSE

The aim of this study was to determine the upgrade rate of image-guided core needle biopsy (CNB)-proven benign breast intraductal papillomas (IDPs) without atypia to high-risk benign lesions or malignancy after surgical excision.

METHODS

A retrospective database search at a single institution identified 102 adult female patients with benign breast IDPs without atypia diagnosed on imaging-guided CNBs who subsequently had surgical excisions between 2011 and 2016. Patient characteristics, imaging features, biopsy techniques, and the pathology reports from imaging-guided CNBs and subsequent surgical excisions were reviewed. The upgrade rate to malignancies or high-risk benign lesions was determined at the patient level.

RESULTS

The upgrade rate to malignancy was 2.9% (3/102), including two cases of ductal carcinoma in situ (DCIS) and one case of microinvasive (< 1 mm) ductal carcinoma arising from DCIS. The upgrade rate to high-risk benign lesions was 7.8% (8/102), with seven cases of atypical ductal hyperplasia and one case of atypical lobular hyperplasia. A personal history of breast cancer and a larger mean lesion size were significantly associated with an upgrade to malignancy (p < 0.05).

CONCLUSIONS

The management of benign breast IDPs without atypia detected on imaging-guided CNBs is controversial. Our results suggest risk stratification is important in approaching these patients. Although surgical excision should be considered for all benign breast IDPs without atypia, observation with serial imaging may be appropriate in selected low-risk patients. This approach will save many women from surgeries and decrease the cost of medical care.