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

False-Positive and False-Negative Contrast-enhanced Mammograms: Pitfalls and Strategies to Improve Cancer Detection

Contrast-enhanced mammography (CEM) is a relatively new breast imaging modality that uses intravenous contrast material to increase detection of breast cancer. CEM combines the structural information of conventional mammography with the functional information of tumor neovascularity. Initial studies have demonstrated that CEM and MRI perform with similar accuracies, with CEM having a slightly higher specificity (fewer false positives), although larger studies are needed. There are various reasons for false positives and false negatives at CEM. False positives at CEM can be caused by benign lesions with vascularity, including benign tumors, infection or inflammation, benign lesions in the skin, and imaging artifacts. False negatives at CEM can be attributed to incomplete or inadequate visualization of lesions, marked background parenchymal enhancement (BPE) obscuring cancer, lack of lesion contrast enhancement due to technical issues or less-vascular cancers, artifacts, and errors of lesion perception or characterization. When possible, real-time interpretation of CEM studies is ideal. If additional views are necessary, they may be obtained while contrast material is still in the breast parenchyma. Until recently, a limitation of CEM was the lack of CEM-guided biopsy capability. However, in 2020, the U.S. Food and Drug Administration cleared two devices to support CEM-guided biopsy using a stereotactic biopsy technique. The authors review various causes of false-positive and false-negative contrast-enhanced mammograms and discuss strategies to reduce these diagnostic errors to improve cancer detection while mitigating unnecessary additional imaging and procedures. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

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.

Selective surgical excision of high-risk lesions

Intraductal papilloma, flat epithelial atypia, radial scar, atypical lobular hyperplasia, and lobular carcinoma in situ have historically been referred to as high-risk lesions and managed with routine surgical excision after diagnosis on core needle biopsy. The misnomer high-risk stems from high rates of upgrade to malignancy reported in historic literature. However, recent studies have found much lower upgrade rates, <2%, than previously thought. These findings are explained by advances in imaging technology, larger-bore biopsy needles, and emphasis on radiology-pathology concordance. Concordant lesions have a low upgrade risk and can be managed with radiographic and clinical surveillance instead of surgical excision. Surgical de-escalation is feasible for many of these lesions with careful multidisciplinary review and a detailed risk-benefit discussion with patients.

Clinicopathological and Imaging Features of Breast Papillary Lesions and Their Association with Pathologic Nipple Discharge

No studies have evaluated whether any clinicopathological or imaging characteristics of breast papillary lesions are associated with pathological nipple discharge (PND). We analyzed 301 surgically confirmed papillary breast lesions diagnosed between January 2012 and June 2022. We evaluated clinical (age of patient, size of lesion, pathologic nipple discharge, palpability, personal/family history of breast cancer or papillary lesion, location, multiplicity, and bilaterality) and imaging characteristics (Breast Imaging Reporting and Data System (BI-RADS), sonographic, and mammographic findings) and compared malignant versus non-malignant lesions and papillary lesions with versus without PND. The malignant group was significantly older than the non-malignant group (p < 0.001). Those in the malignant group were more palpable and larger (p < 0.001). Family history of cancer and peripheral location in the malignant group were more frequent than in the non-malignant group (p = 0.022 and p < 0.001). The malignant group showed higher BI-RADS, irregular shape, complex cystic and solid echo pattern, posterior enhancement on ultrasound (US), fatty breasts, visibility, and mass type on mammography (p < 0.001, 0.003, 0.009, <0.001, <0.001, <0.001, and 0.01, respectively). On multivariate logistic regression analysis, peripheral location, palpability, and age of ≥50 years were factors significantly associated with malignancy (OR: 4.125, 3.556, and 3.390, respectively; p = 0.004, 0.034, and 0.011, respectively). Central location, intraductal nature, hyper/isoechoic pattern, and ductal change were more frequent in the PND group (p = 0.003, p < 0.001, p < 0.001, and p < 0.001, respectively). Ductal change was significantly associated with PND on multivariate analysis (OR, 5.083; p = 0.029). Our findings will help clinicians examine patients with PND and breast papillary lesions more effectively.

[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.

Breast cancer risk in papilloma patients: Osteopontin splice variants indicate prognosis

BACKGROUND

Papillomas of the breast pose challenges for treatment decisions as their risk for transformation to breast cancer is low but not negligible. To spare low-risk patients the burden of substantial treatment side effects, prognostic indicators are needed for cancerous progression. The secreted metastasis mediator Osteopontin (OPN) is a marker for breast cancer aggressiveness, and its variants are prognosticators for transformation in diverse premalignant breast lesions. Here, we test whether the presence of OPN-c or OPN-exon-4 in papillomatous lesions may reflect progression risk.

METHODS

By immunohistochemistry, we analyze OPN-c and OPN-exon-4 in papillomas from 114 women as well as correlations between staining and progression. In departure from prior spliced OPN biomarker publications, we utilize novel monoclonal antibodies.

RESULTS

Fewer than 5% of OPN-c pathology score 0-1 (intensity) versus almost 18% of score 2-3 experienced cancer in follow-up. Nine of 12 women, who progressed, had pathology scores of 2-3 for OPN-c intensity at the time of initial diagnosis, and none had a score of 0. When developing a combined risk score from intensity plus percent positivity for OPN-c, the progression risk for patients with low score was 3.2%, for intermediate score was 5.7%, and for high score was 18.8%. Papillomas in patients, who were later diagnosed with cancer in the contralateral breast, displayed stronger staining positivity than non-progressors.

CONCLUSION

OPN splice variant immunohistochemistry on biopsies of breast papillomas will allow counseling of the patients on their risk to develop breast cancer at a later time.

Solitary Dilated Ducts Revisited: Malignancy Rate and Implications for Management

RATIONALE AND OBJECTIVES

A solitary dilated duct (SDD) is a single asymmetrically dilated breast duct with diameter more than 2 mm. The Breast Imaging Reporting and Data System (BI-RADS) fifth edition recommends additional imaging and biopsy for SDDs without demonstrated benign etiology, however management of this rare entity remains controversial. This study describes practice patterns, malignancy rate, and features associated with high-risk/malignant SDDs to better stratify patients requiring biopsy versus follow-up.

MATERIALS AND METHODS

This IRB-approved retrospective study identified mammographic, sonographic and MRI exams utilizing the term "solitary dilated duct" at a multisite academic institution between 1/1/2010 and 12/31/2020. Clinical and imaging features, BI-RADS assessments, and outcomes were analyzed. Univariate and multivariate analyses identified predictors of high-risk/malignant histology.

RESULTS

SDDs identified in 49 women (mean age 56.1 years) were assessed as BI-RADS 4/5 (31/49, 63%), BI-RADS 3 (9/49, 18%), or BI-RADS 2 (9/49, 18%). Most sampled lesions were benign (16/31, 52%) and the remaining were high-risk (15/31, 48%, all papillary lesions). The only papilloma with atypia on core biopsy upgraded to grade 2 DCIS on excision (malignancy rate 1/49, 2%). All anechoic SDDs were benign (n=13), and all benign SDDs lacked internal vascularity. SDDs with associated masses were associated with malignant/high-risk outcomes on multivariate analysis (p < .001).

CONCLUSION

The BI-RADS fifth edition recommends biopsy for SDDs without demonstrated benign etiology. In our 11-year study period, practice patterns were variable with a low malignancy rate of 2%. Our findings suggest that anechoic SDDs may be followed, and SDDs with associated masses or internal vascularity require biopsy.

Nipple Discharge Imaging Evaluation with Mammography, Ultrasound, Galactography, and MRI

RATIONALE AND OBJECTIVE

To determine the diagnostic yield of various imaging tests used to evaluate nipple discharge.

MATERIALS AND METHODS

A single institution, IRB-approved, retrospective study was performed of 320 consecutive patients presenting with nipple discharge. Imaging and pathology were reviewed to determine the yield for malignancy, atypical high-risk lesions (HRLs), and intraductal papillomas (IDPs).

RESULTS

Of the 320 patients, pathology or follow up confirmed 40 breast malignancies (40/320, 12.5%),14 atypical HRLs (14/320, 4.4%), 71 IDPs (71/320, 22.2%), 48 other benign pathologies (48/320,15.0%), and 147 unknown but benign cases (147/320, 45.9%). Physiologic discharge characteristics were observed in a minority of malignant cases: nonspontaneous (4/40, 10.0%); neither bloody nor clear (4/40, 10.0%); bilateral (3/40, 7.5%). Malignancy was associated with older age (p < 0.001) and bloody discharge (odds ratio 6.5, p < 0.0001). The combination of digital mammography and ultrasound had a 93% sensitivity and a 98% NPV, while contrast enhanced MRI (CE-MRI) had a 100% sensitivity and a 100% NPV for malignancy. Only three galactography examinations were performed among the malignant cohort, with minimal contribution (1 of 3) to the diagnostic evaluation. In this case, galactography findings helped determine imaging-pathology discordance, prompting a recommendation for surgical excision and subsequently a malignant diagnosis.

CONCLUSION

The combination of mammography and ultrasonography detected 93% of breast malignancies associated with nipple discharge and had a 98% NPV for malignancy. The value of CE-MRI is its ability to detect the remaining malignancies, not detected on mammography or ultrasound, and its ability to obviate the need for surgical duct excision.

A retrospective study evaluating outcomes of surgical excision versus radiologic follow-up of benign breast papillomas without atypia

BACKGROUND

There is uncertainty whether benign breast papillomas without atypia (BP) can be followed by imaging or require surgical resection.

METHODS

A single-center, retrospective cohort study of patients diagnosed with BP (2011-2021) to determine the upgrade rate on surgery, and factors associated with surgical intervention and upgrade.

RESULTS

139 BPs were included. 27(19.4%) had upfront surgery; 112(80.6%) had imaging follow-up. The upfront surgery group had higher rates of pre-excision nipple inversion (n = 2(8.3%)vs.n = 0(0%),p = 0.003). In the imaging group, the median follow-up was 3.8years, and 9 had subsequent resection. Upgrade rate was 5.8%(8/139). Of all BPs undergoing surgery (n = 36), patients ≥60years (75.0%vs.25.0%,p = 0.049) or with family history of breast cancer (87.5%vs.48.1%,p = 0.048) were more likely to have upgrade.

CONCLUSIONS

Despite a low number of events, this study supports radiologic follow-up of BP except in patients ≥60 years or with family history of breast cancer, adding to the growing body of evidence supporting watchful waiting of BPs.

Intraductal Papilloma on Breast Biopsy: Upstaging Rate and Implications for Practice Guidelines

BACKGROUND

The recommendation for management of intraductal papilloma has not been clearly established and its surgical excision criteria remain controversial. This study determines the institutional malignancy upstage rate of benign intraductal papillomas and identifies risk factors for upstage.

METHODS

Retrospective review was conducted on female patients who were diagnosed with intraductal papillomas without atypia on core needle biopsy at Atrium Health Wake Forest Baptist Hospital between 1/2012 and 6/2021. Patients were excluded if there was a concomitant malignancy or atypia or deemed to be discordant with imaging. Features associated with upstage on imaging and histopathology were obtained from the electronic medical record.

RESULTS

This study included 245 intraductal papillomas without atypia in 231 women (mean age, 59.1 ± 12.3 [SD] years). Approximately 31% (76/245) of the papillomas were excised, whereas 69% (169/245) of the papillomas underwent surveillance. Of the patients who underwent excisional biopsy, upstage rate for DCIS was 1.3% (1/76) and 5.3% (4/76) for atypia. All of the papillomas upstaged to DCIS or atypia had lesion size ≥10 mm on imaging. Out of the 139 intraductal papillomas that underwent radiologic surveillance, two (1.4%) developed malignancy and three (2.2%) developed atypia.

DISCUSSION

The risk of upstaging of intraductal papilloma without atypia to malignancy remains extremely low. Therefore, routine surgical excision may not be necessary. While the papillomas upstaged to either malignancy or atypia have size abnormality ≥10 mm, other potential selective excision criteria should be explored to further decrease the risk of an upstage.

Papillary Neoplasms of the Breast: Diagnostic Features and Molecular Insights

Papillary neoplasms of the breast are a heterogeneous group of tumors characterized by fibrovascular cores lined by epithelium, with or without myoepithelial cells. Papillary neoplasms include benign, atypical, and malignant tumors that show varying histopathologic features and clinical outcomes. Appropriate pathologic classification is crucial to guide clinical treatment. Classification of papillary neoplasms is largely based on morphology, with immunohistochemistry playing an ancillary role to establish diagnoses. Recent molecular studies have provided insight into the genomics of these lesions. This review summarizes the histologic, immunohistochemical, and molecular features of papillary neoplasms of the breast that are important for diagnosis and treatment.