Sonographic evaluation of infiltrating lobular carcinoma

Breast Radiologists' Perceptions on the Detection and Management of Invasive Lobular Carcinoma: Most Agree Imaging Beyond Mammography Is Warranted

OBJECTIVE

To determine breast radiologists' confidence in detecting invasive lobular carcinoma (ILC) on mammography and the perceived need for additional imaging in screening and preoperative settings.

METHODS

A 16-item anonymized survey was developed, and IRB exemption obtained, by the Society of Breast Imaging (SBI) Patient Care and Delivery Committee and the Lobular Breast Cancer Alliance. The survey was emailed to 2946 radiologist SBI members on February 15, 2023. The survey recorded demographics, perceived modality-specific sensitivity for ILC to the nearest decile, and opinions on diagnosing ILC in screening and staging imaging. Five-point Likert scales were used (1 = strongly disagree, 2 = disagree, 3 = neutral, 4 = agree, 5 = strongly agree).

RESULTS

Response rate was 12.4% (366/2946). Perceived median (interquartile range) modality-specific sensitivities for ILC were MRI 90% (80-90), contrast-enhanced mammography 80% (70-90), molecular breast imaging 80% (60-90), digital breast tomosynthesis 70% (60-80), US 60% (50-80), and 2D mammography 50% (30-60). Only 25% (85/340) respondents were confident in detecting ILC on screening mammography in dense breasts, while 67% (229/343) were confident if breasts were nondense. Most agreed that supplemental screening is needed to detect ILC in women with dense breasts (272/344, 79%) or a personal history of ILC (248/341, 73%), with 34% (118/334) indicating that supplemental screening would also benefit women with nondense breasts. Most agreed that additional imaging is needed to evaluate extent of disease in women with newly diagnosed ILC, regardless of breast density (dense 320/329, 97%; nondense 263/329, 80%).

CONCLUSION

Most breast radiologists felt that additional imaging beyond mammography is needed to more confidently screen for and stage ILC.

Lobular Carcinoma of the Breast: A Comprehensive Review with Translational Insights

The second most common breast carcinoma, invasive lobular carcinoma, accounts for approximately 15% of tumors of breast origin. Its incidence has increased in recent times due in part to hormone replacement therapy and improvement in diagnostic modalities. Although believed to arise from the same cell type as their ductal counterpart, invasive lobular carcinomas (ILCs) are a distinct entity with different regulating genetic pathways, characteristic histologies, and different biology. The features most unique to lobular carcinomas include loss of E-Cadherin leading to discohesion and formation of a characteristic single file pattern on histology. Because most of these tumors exhibit estrogen receptor positivity and Her2 neu negativity, endocrine therapy has predominated to treat these tumors. However novel treatments like CDK4/6 inhibitors have shown importance and antibody drug conjugates may be instrumental considering newer categories of Her 2 Low breast tumors. In this narrative review, we explore multiple pathological aspects and translational features of this unique entity. In addition, due to advancement in technologies like spatial transcriptomics and other hi-plex technologies, we have tried to enlist upon the characteristics of the tumor microenvironment and the latest associated findings to better understand the new prospective therapeutic options in the current era of personalized treatment.

A role for breast ultrasound Artificial Intelligence decision support in the evaluation of small invasive lobular carcinomas

OBJECTIVE

To evaluate the diagnostic performance of an Artificial Intelligence (AI) decision support (DS) system in the ultrasound (US) assessment of invasive lobular carcinoma (ILC) of the breast, a cancer that can demonstrate variable appearance and present insidiously.

METHODS

Retrospective review was performed of 75 patients with 83 ILC diagnosed by core biopsy or surgery between November 2017 and November 2019. ILC characteristics (size, shape, echogenicity) were recorded. AI DS output (lesion characteristics, likelihood of malignancy) was compared to radiologist assessment.

RESULTS

The AI DS system interpreted 100% of ILCs as suspicious or probably malignant (100% sensitivity, and 0% false negative rate). 99% (82/83) of detected ILCs were initially recommended for biopsy by the interpreting breast radiologist, and 100% (83/83) were recommended for biopsy after one additional ILC was identified on same-day repeat diagnostic ultrasound. For lesions in which the AI DS output was probably malignant, but assigned a BI-RADS 4 assessment by the radiologist, the median lesion size was 1 cm, compared with a median lesion size of 1.4 cm for those given a BI-RADS 5 assessment (p = 0.006). These results suggest that AI may offer more useful DS in smaller sub-centimeter lesions in which shape, margin status, or vascularity is more difficult to discern. Only 20% of patients with ILC were assigned a BI-RADS 5 assessment by the radiologist.

CONCLUSION

The AI DS accurately characterized 100% of detected ILC lesions as suspicious or probably malignant. AI DS may be helpful in increasing radiologist confidence when assessing ILC on ultrasound.

Multimodality imaging in lobular breast cancer: Differences in mammography, ultrasound, and MRI in the assessment of local tumor extent and correlation with molecular characteristics

Introduction

Invasive lobular breast cancer (ILC) is a diagnostic challenge due to the diversity of morphological features. The objective of the study was to investigate the presentation and local extent of ILC using various imaging techniques and to assess the correlation between imaging and molecular profile.

Materials and methods

We reviewed 162 consecutive patients with ILC found on vacuum-assisted biopsy, who underwent evaluation of the lesion morphology and extent using ultrasound (US), mammography (MMG), and magnetic resonance imaging (MRI). Radiographic features were compared with ILC intrinsic subtype based on the expression of Ki-67 and estrogen, progesterone, and HER2 receptors.

Results

A total of 113 mass lesions and 49 non-mass enhancements (NMEs) were found in MRI. Masses were typically irregular and spiculated, showing heterogeneous contrast enhancement, diffusion restriction, and type III enhancement curve. NMEs presented mainly as the area of focal or multiregional distribution with heterogeneous or clumped contrast enhancement, diffusion restriction, and type III enhancement curve. Lesion extent significantly varied between MRI and MMG/ultrasonography (USG) (P < 0.001) but did not differ between MGF and ultrasonography (USG). The larger the ILC, the higher the disproportion when lesion extent in MRI was compared with MMG (P < 0.001) and ultrasonography (USG) (P < 0.001). In the study group, there were 97 cases of luminal A subtype (59.9%), 54 cases of luminal B HER2− (33.3%), nine cases of luminal B HER2+ (5.5%), and two cases of triple negative (1.2%). The HER2 type was not found in the study group. We did not observe any significant correlation between molecular profile and imaging.

Conclusion

MRI is the most effective technique for the assessment of ILC local extent, which is important for optimal treatment planning. Further studies are needed to investigate if the intrinsic subtype of ILC can be predicted by imaging features on MRI.

Current and future diagnostic and treatment strategies for patients with invasive lobular breast cancer

BACKGROUND

Invasive lobular breast cancer (ILC) is the second most common type of breast cancer after invasive breast cancer of no special type (NST), representing up to 15% of all breast cancers.

DESIGN

Latest data on ILC are presented, focusing on diagnosis, molecular make-up according to the European Society for Medical Oncology Scale for Clinical Actionability of molecular Targets (ESCAT) guidelines, treatment in the early and metastatic setting and ILC-focused clinical trials.

RESULTS

At the imaging level, magnetic resonance imaging-based and novel positron emission tomography/computed tomography-based techniques can overcome the limitations of currently used imaging techniques for diagnosing ILC. At the pathology level, E-cadherin immunohistochemistry could help improving inter-pathologist agreement. The majority of patients with ILC do not seem to benefit as much from (neo-)adjuvant chemotherapy as patients with NST, although chemotherapy might be required in a subset of high-risk patients. No differences in treatment efficacy are seen for anti-human epidermal growth factor receptor 2 (HER2) therapies in the adjuvant setting and cyclin-dependent kinases 4 and 6 inhibitors in the metastatic setting. The clinical utility of the commercially available prognostic gene expression-based tests is unclear for patients with ILC. Several ESCAT alterations differ in frequency between ILC and NST. Germline BRCA1 and PALB2 alterations are less frequent in patients with ILC, while germline CDH1 (gene coding for E-cadherin) alterations are more frequent in patients with ILC. Somatic HER2 mutations are more frequent in ILC, especially in metastases (15% ILC versus 5% NST). A high tumour mutational burden, relevant for immune checkpoint inhibition, is more frequent in ILC metastases (16%) than in NST metastases (5%). Tumours with somatic inactivating CDH1 mutations may be vulnerable for treatment with ROS1 inhibitors, a concept currently investigated in early and metastatic ILC.

CONCLUSION

ILC is a unique malignancy based on its pathological and biological features leading to differences in diagnosis as well as in treatment response, resistance and targets as compared to NST.

Special Histologic Type and Rare Breast Tumors - Diagnostic Review and Clinico-Pathological Implications

Breast cancer is the most common malignant tumor in females. While most carcinomas are categorized as invasive carcinoma, no special type (NST), a diverse group of tumors with distinct pathologic and clinical features is also recognized, ranging in incidence from relatively more common to rare. So-called "special histologic type" tumors display more than 90% of a specific, distinctive histologic pattern, while a spectrum of tumors more often encountered in the salivary gland may also arise in the breast. Metaplastic carcinomas can present diagnostic challenges. Some uncommon tumors harbor pathognomonic genetic alterations. This article provides an overview of the key diagnostic points and differential diagnoses for this group of disparate lesions, as well as the salient clinical characteristics of each entity.

Stereotactic Vacuum-Assisted Needle Biopsy Outcomes of Non-calcified Mammographic Lesions

RATIONALE AND OBJECTIVES

To identify the outcomes of stereotactic vacuum-assisted large bore biopsies performed on sonographically-occult non-calcified mammographic lesions (NCL).

MATERIALS AND METHODS

In an IRB-approved retrospective study, we reviewed all NCL that underwent stereotactic biopsy from January 1, 2014 to December 31, 2017 at our institution, comparing patient age, lesion type, size and location with pathology outcome (benign, high-risk or malignant) using Wilcoxon-Mann-Whitney or Fisher's exact tests as appropriate. Multivariable logistic regression models were developed to decrease benign biopsies in our cohort with diagnostic performance assessed using receiver operating characteristic curve and area under the curve (AUC).

RESULTS

Of 222 biopsied lesions in 213 patients, 79.3% (176/222) were benign, 5.9% (13/222) malignant, and 14.9% (33/222) high-risk. NCL were less likely to be malignant compared to calcifications biopsied in the same period [5.9% vs 19.0% (243/1279), p < 0.001]. All 42 asymmetries and 33 architectural distortions were benign, while 8.7% (4/46) of masses and 8.9% (9/101) of focal asymmetries were malignant. Cancers were associated with older age (mean 65.2 vs 52.7 years, p < 0.001), smaller size (mean 9.5 mm vs 15.5 mm, p < 0.01), and concurrent breast cancer (p < 0.01) compared to benign/high-risk lesions. Multivariable logistic regression model using patient age >50 years, lesion type, and size <15 mm had a high diagnostic performance [AUC=0.89, 95%CI (0.83, 0.94)], and yielded the highest PPV [0.24; 95%CI (0.13, 0.38)], and highest number of avoided, unnecessary biopsies (172/209, 82%).

CONCLUSION

NCL biopsied under stereotactic guidance have low cancer yield (5.9%). A multivariate model integrating age, lesion size and type could potentially help avoid unwarranted biopsies in our cohort.

Lobular Breast Cancer: A Review

Invasive lobular carcinoma accounts for 5%–15% of all invasive breast cancers, with a marked increase in incidence rates over the past two decades. Distinctive biological hallmarks of invasive lobular carcinoma include the loss of cell adhesion molecule E-cadherin leading to cells with a discohesive morphology, proliferating into single-file strands and estrogen receptor positivity. These key molecular features can make diagnosis difficult, as invasive lobular carcinoma is challenging to detect both physically and with current standard imaging. Treatment of invasive lobular carcinoma strongly favors endocrine therapy due to low chemosensitivity and lower rates of pathological response as a result. This review will summarize the distinct biological and molecular features of invasive lobular carcinoma, focusing on the diagnostic challenges faced and the subsequent surgical and medical management strategies. Prospective therapeutic options will also be explored, highlighting how furthering our understanding of the unique biology of lobular breast carcinoma is essential in guiding and informing the treatment of patients in the future.

Imaging of Breast Cancers With Predilection for Nonmass Pattern of Growth: Invasive Lobular Carcinoma and DCIS-Does Imaging Capture It All?

OBJECTIVE. Invasive lobular carcinoma (ILC) and ductal carcinoma in situ (DCIS) are distinct histopathologic entities with several commonalities: both have subtle clinical and imaging presentation, have been linked with controversy regarding optimal imaging techniques and management, and exemplify the codependence of adequate imaging evaluation and optimal treatment strategies in breast care. CONCLUSION. We review molecular mechanisms and histopathologic patterns that define the biologic behavior of both ILC and DCIS and discuss how these mechanisms translate into distinct clinical and imaging presentations that affect the staging workup and patient management algorithm.

Invasive Lobular Breast Cancer as a Distinct Disease: Implications for Therapeutic Strategy

Invasive lobular carcinoma comprises 10-15% of all breast cancers and is increasingly recognised as a distinct and understudied disease compared with the predominant histological subtype, invasive ductal carcinoma. Hallmarks of invasive lobular carcinoma include E-cadherin loss, leading to discohesive morphology with cells proliferating in single-file strands and oestrogen receptor positivity, with favourable response to endocrine therapy. This review summarises the distinct histological and molecular features of invasive lobular carcinoma with focus on diagnostic challenges and the impact on surgical management and medical therapy. Emphasis is placed on recent advances in our understanding of the unique molecular biology of lobular breast cancer and how this is optimising our therapy approach in the clinic.

[Diagnostic and therapeutic features of invasive lobular carcinoma of the breast: a study of 30 cases]

Le cancer lobulaire infiltrant (CLI) du sein représente 5 à 15% des cancers du sein, il est classé le deuxième type histologique le plus fréquent, après le cancer infiltrant de type non spécifique (CINS) et son incidence est en nette augmentation. Son diagnostic clinique et radiologique est difficile. Il est plus fréquemment bilatéral. C'est un cancer d'évolution plus lente que le CINS avec de meilleurs facteurs pronostiques notre étude vise à détailler les caractéristiques cliniques, radiologiques, thérapeutiques et pronostiques du CLI. Il s'agit d'une étude rétrospective descriptive de 30 cas de CLI du sein colligé au Centre de Maternité et Néonatologie Monastir sur une période de 10 ans. L'incidence du CLI était de 5,2%. L'âge moyen est de 53,43 ans. Dix pourcent avaient des antécédents personnels de mastopathies bénignes, 6,66% avaient des antécédents personnels du cancer du sein et 3,33% avaient des antécédents familiaux du cancer du sein. Le CLI était diagnostiqué à un stade tardif chez 18 cas. La masse était bifocale chez 5 patientes, multifocale chez 4 patientes et bilatérale chez 3 patientes. Une seule patiente avait présenté une métastase hépatique lors du diagnostic. La chirurgie radicale type Patey était réalisée d'emblée chez 63,33% des patientes. Des lésions multifocales étaient détectées dans 44,80% des cas lors de l'examen anatomopathologique. Le curage ganglionnaire était positif chez 21 patientes. Vingt-huit patientes soit 93,33% avaient bénéficié d'une radiothérapie et d'hormonothérapie adjuvante. La survie globale à 5 ans était estimée à 77,3%.

Preoperative loco-regional staging of invasive lobular carcinoma with contrast-enhanced digital mammography (CEDM)

The aim of our study was to assess the performance of contrast-enhanced digital mammography (CEDM) in the preoperative loco-regional staging of invasive lobular carcinoma (ILC) patients, about the valuation of the extension of disease and in measurement of lesions. Then, we selected retrospectively, among the 1500 patients underwent to CEDM at the Breast Diagnostics Department of the Careggi University Hospital of Florence and the National Cancer Institute of Milan from September 2016 to November 2018, 31 women (mean age 57.1 aa; range 41-78 aa) with a definitive histological diagnosis of ILC. CEDM has proved to be a promising imaging technique, being characterized by a sensitivity of 100% in the detection of the index lesion, and of 84.2% in identifying any adjunctive lesions: It was the presence of a non-mass enhancement (NME) to lower the sensitivity of the technique (25% vs. 100% for mass-like enhancements or a mass closely associated with a NME). Specificity in the characterization of additional lesions was 66.7%, and the diagnosis of the extension of disease was correct in 77.4% of cases: NME also led to a decrease in diagnostic accuracy in the evaluation of disease extension up to 40% versus 85% for masses and 80% for masses associated with NME (M/NME). Moreover, in 12/31 (38.7%), CEDM allowed to correctly identify lesions not shown by mammography + ultrasonography + tomosynthesis: In the half of these (6/12), there was a multicentricity, thus allowing an adequate surgical planning change. CEDM was also very accurate in analyzing the maximum diameter of the masses, while it was much less reliable in the case of the M/NME and pure NME. In conclusion, CEDM is a new promising imaging technique in the loco-regional preoperative staging and in the evaluation of disease extension for ILC, especially in case of mass enhancement lesions.

Association between ultrasound morphologic features and histopathological findings of lobular carcinoma

INTRODUCTION

Despite the incidence and recurrence rates of breast cancer, there are currently no biomarkers to predict which cases will develop into lobular carcinoma (LC). The purpose of this study was to determine the association between ultrasound morphologic characteristics of LC and histopathological classifications.

METHODS

A retrospective, cross-sectional study was conducted on the ultrasound images and histopathological reports of 100 patients with a confirmed LC diagnosis between January 2013 and December 2016.

RESULTS

Morphologic ultrasound characteristics most frequently reported in the dataset of positively diagnosed LC patients were; irregular ultrasound shape (86%), hypoechoic echogenicity (88%), poorly circumscribed margin (95%), posterior acoustic enhancement (93%) and absent calcifications (81%). Using Fisher's extract test, it was found that stromal fibrosis, single file type pattern, atypical lobular hyperplasia and LC Grade II were significantly correlated with irregular shape and hypoechoic echogenicity.

CONCLUSION

A prognostic predictor tool can be designed from this study's findings which can then be used in practice to raise awareness of the unique morphometric markers related to LC of the breast.

Invasive lobular breast cancer: A review of pathogenesis, diagnosis, management, and future directions of early stage disease

Invasive lobular carcinoma (ILC) is the second most common type of invasive breast cancer after invasive ductal carcinoma (IDC). Invasive lobular carcinoma has unique clinical, pathologic, and radiographic features which suggest that it is a distinct clinical entity; however, it is treated with the same treatment paradigms as IDC. Information regarding the specific treatment of ILC, including response to standard therapy, is sparse. Neoadjuvant treatment considerations are of great importance in this space as ILC is often found at a locally advanced stage. In this review, we summarize the classic features of ILC and the available data regarding efficacy of both endocrine therapy and chemotherapy in curative treatment of breast cancer.

Digital Breast Tomosynthesis: What Have We Learned?

Digital breast tomosynthesis (DBT) is increasingly recognized as a superior breast imaging technology compared with 2D digital mammography (DM) alone. Accumulating data confirm increased sensitivity and specificity in the screening setting, resulting in higher cancer detection rates and lower abnormal interpretation (recall) rates. In the diagnostic environment, DBT simplifies the diagnostic work-up and improves diagnostic accuracy. Initial concern about increased radiation exposure resulting from the DBT acquisition added onto a 2D mammogram has been largely alleviated by the development of synthesized 2D mammography (SM). Continued research is underway to reduce artifacts associated with SM, and improve its comparability to DM. Breast cancers detected with DBT are most often small invasive carcinomas with a preponderance for grade 1 histology and luminal A molecular characteristics. Recent data suggest that higher-grade cancers are also more often node negative when detected with DBT. A meta-analysis of early single-institution studies of the effect of DBT on interval cancers has shown a modest decrease when multiple data sets are combined. Because of the greater conspicuity of lesions on DBT imaging, detection of subtle architectural distortion is increased. Such findings include both spiculated invasive carcinomas and benign etiologies such as radial scars. The diagnostic evaluation of architectural distortion seen only with DBT can pose a challenge. When no sonographic correlate can be identified, DBT-guided biopsy and/or localization capability is essential. Initial experience with DBT-guided procedures suggests that DBT biopsy equipment may improve the efficiency of percutaneous breast biopsy with less radiation.

Accuracy of Ultrasound for Preoperative Assessment of Tumor Size in Patients With Newly Diagnosed Breast Cancer: Is It Affected by the Background Parenchymal Echotexture?

OBJECTIVES

To assess the impact of the background parenchymal echotexture on the accuracy of tumor size estimation using breast ultrasound (US).

METHODS

A total of 140 women with newly diagnosed invasive breast cancer from January 2014 to December 2015 were enrolled in this study. Two radiologists retrospectively reviewed US images in consensus for background parenchymal echotexture interpretation. The maximum tumor diameter from static images was recorded. Tumor size measurements were considered as having agreement with histologic results if they were within ±5 mm compared to the pathologic size. The relationship between the accuracy of tumor size measurement by the background parenchymal echotexture and clinicopathologic characteristics was evaluated.

RESULTS

Of these 140 patients, 77 (55.0%) showed a homogeneous background parenchymal echotexture, whereas 63 (45.0%) showed a heterogeneous echotexture. The mean tumor size was 1.9 cm (range, 0.5-4.9 cm). The overall accuracy of tumor size measurement was 76.4% (104 of 140). Tumors of women with a homogeneous background parenchymal echotexture were more accurately measured than those of women with a heterogeneous echotexture (87.0% versus 63.5%; P = .001). Tumors with a small size (<2 cm; P = .018) and ductal carcinoma in situ-negative (P = .031), human epidermal growth factor receptor 2 (HER2)-negative (P = .053), and triple-negative (P = .016) types were also more accurately measured. The independent factors associated with inaccurate tumor size measurement were a heterogeneous background parenchymal echotexture, a large tumor size, and the HER2-enriched type (P < .05).

CONCLUSIONS

The background parenchymal echotexture affected the accuracy of tumor size estimation using breast US. Invasive breast cancers with large (≥2 cm) tumors and the HER2-enriched type showed significantly lower breast US accuracy compared to others.

Unifocal Invasive Lobular Carcinoma: Tumor Size Concordance Between Preoperative Ultrasound Imaging and Postoperative Pathology

BACKGROUND

We systematically analyzed the extent of disease in unifocal invasive lobular carcinoma (ILC) using ultrasonography, with the histopathologic findings as the reference standard.

PATIENTS AND METHODS

In the present single-institution retrospective study, 128 cases of ILC were identified during a 5-year period. After exclusions, the analyzed cohort included 66 cases. Ultrasound measurements of the tumor extent along 3 axes were obtained. The tumor size was determined as the largest extent among the 3 axes and the tumor volume by ellipsoidal approximation. Pathology review provided the tumor size and volume. Correlation and regression analyses of tumor size and volume from the ultrasound and pathologic examinations were performed. The tumor stage from the ultrasound and pathologic examinations were used for the concordance analyses.

RESULTS

The median and quartiles (Q1, Q3) of tumor size from ultrasonography and pathology were 12.5 mm (Q1, 9 mm; Q3, 19 mm) and 17 mm (Q1, 12 mm; Q3, 25 mm), respectively. The corresponding data for tumor volume were 0.52 cm³ (Q1, 0.18 cm³; Q3, 1.92 cm³) and 1.04 cm³ (Q1, 0.45 cm³; Q3, 2.49 cm³). The ultrasound measurements correlated with the pathology-reported tumor size (Spearman ρ = 0.678; P < .0001) and volume (Spearman ρ = 0.699; P < .0001). The ultrasound-measured size and volume differed from the pathology-reported size and volume (P < .0001; Wilcoxon signed ranks test). Concordance between the clinical tumor size stage from ultrasound (cT) and pathology tumor size stage (pT) varied with the pT stage (P = .0003, Fisher's exact test), with the greatest concordance rate of 95.7% (95% confidence limit, 85.2%-99.5%) observed for pT1 tumors.

CONCLUSION

Ultrasonography underestimates the tumor size and volume, with the underestimation increasing for larger tumors. Hence, the concordance rate in tumor size stage between ultrasonography and pathology is tumor size dependent, with the greatest concordance rate observed for pT1 tumors.

Role of Magnetic Resonance Imaging in the Preoperative Staging and Work-Up of Patients Affected by Invasive Lobular Carcinoma or Invasive Ductolobular Carcinoma

Purpose

The prevalence of invasive lobular carcinoma (ILC), the second most common type of breast cancer, accounts for 5%-15% of all invasive breast cancer cases. Its histological feature to spread in rows of single cell layers explains why it often fails to form a palpable lesion and the lack of sensitivity of mammography and ultrasound (US) to detect it. It also has a higher incidence of multifocal, multicentric, and contralateral disease when compared to the other histological subtypes. The clinicopathologic features and outcomes of Invasive Ductolobular Carcinoma (IDLC) are very similar to the ILC. The purpose of our study is to assess the importance of MRI in the preoperative management and staging of patients affected by ILC or IDLC.

Materials and Methods

We identified women diagnosed with ILC or IDLC. We selected the patients who had preoperative breast MRI. For each patient we identified the areas of multifocal, multicentric, or contralateral disease not visible to standard exams and detected by preoperative MRI. We analyzed the potential correlation between additional cancer areas and histological cancer markers.

Results

Of the 155 women who met our inclusion criteria, 93 (60%) had additional cancer areas detected by MRI. In 61 women, 39,4% of the overall population, the additional cancer areas were confirmed by US/tomosynthesis second look and biopsy. Presurgical MRI staging changed surgical management in the 37,4% of the patients. Only six patients of the overall population needed a reoperation after the initial surgery. No statistically significant correlation was found between MRI overestimation and the presence of histological peritumoral vascular/linfatic invasion. No statistically significant correlation was found between additional cancer areas and histological cancer markers.

Conclusions

Our study suggests that MRI is an important tool in the preoperative management and staging of patients affected by lobular or ductolobular invasive carcinoma.

The adaptive computer-aided diagnosis system based on tumor sizes for the classification of breast tumors detected at screening ultrasound

Screening ultrasound (US) is increasingly used as a supplement to mammography in women with dense breasts, and more than 80% of cancers detected by US alone are 1cm or smaller. An adaptive computer-aided diagnosis (CAD) system based on tumor size was proposed to classify breast tumors detected at screening US images using quantitative morphological and textural features. In the present study, a database containing 156 tumors (78 benign and 78 malignant) was separated into two subsets of different tumor sizes (<1cm and ⩾1cm) to explore the improvement in the performance of the CAD system. After adaptation, the accuracies, sensitivities, specificities and Az values of the CAD for the entire database increased from 73.1% (114/156), 73.1% (57/78), 73.1% (57/78), and 0.790 to 81.4% (127/156), 83.3% (65/78), 79.5% (62/78), and 0.852, respectively. In the data subset of tumors larger than 1cm, the performance improved from 66.2% (51/77), 68.3% (28/41), 63.9% (23/36), and 0.703 to 81.8% (63/77), 85.4% (35/41), 77.8% (28/36), and 0.855, respectively. The proposed CAD system can be helpful to classify breast tumors detected at screening US.

Incremental Cancer Detection of Locoregional Restaging with Diagnostic Mammography Combined with Whole-Breast and Regional Nodal Ultrasound in Women with Newly Diagnosed Breast Cancer

RATIONALE AND OBJECTIVES

This study aims to determine if locoregional restaging with diagnostic mammography and ultrasound (US) of the whole breast and regional nodes performed for quality assurance in women with newly diagnosed breast cancer who were referred to a tertiary care center yields incremental cancer detection.

MATERIALS AND METHODS

An institutional review board-approved retrospective, single-institution database review was performed on the first 1000 women referred to our center in 2010 with a provisional breast cancer diagnosis. Locoregional restaging consisted of diagnostic full-field digital mammography combined with US of the whole breast and regional nodal basins. Bilateral whole-breast US was performed in women with contralateral mammographic abnormality or had heterogeneously or extremely dense parenchyma. Demographic, clinical, and pathologic factors were analyzed.

RESULTS

Final analyses included 401 women. Of the 401 women, 138 (34%) did not have their outside images available for review upon referral. The median age was 54 years (range 21-92); the median tumor size was 2.9 cm (range 0.6-18.0) for women whose disease was upstaged and 2.2 cm (range 0.4-15.0) for women whose disease was not upstaged. Incremental cancer detection rates were 15.5% (62 of 401) in the ipsilateral breast and 3.9% (6 of 154) in the contralateral breast (P < 0.0001). The total upstage rate was 25% (100 of 401). Surgical management changed from segmentectomy to mastectomy in 12% (50 of 401). The re-excision rate after segmentectomy was 19% (35 of 189).

CONCLUSIONS

Locoregional restaging with diagnostic mammography combined with whole-breast and regional nodal US that is performed for standardization of the imaging workup for newly diagnosed breast cancer patients can reduce underestimation of disease burden and impact therapeutic planning.

Ultrasound-guided breast-conserving surgery for early-stage palpable and nonpalpable invasive breast cancer: decreased excision volume at unchanged tumor-free resection margin

Ultrasound guidance (USG) during breast-conserving surgery improves tumor-free surgical resection margins. The objective of this study was to evaluate whether USG reduces resection volumes without compromising margin status. 134 patients with palpable or nonpalpable T1-2N0-1 invasive breast cancer were treated with USG and compared with a historical reference control group (CON) consisting of palpation-guided (PAG) or wire-guided localization (WIG) breast-conserving surgery. Primary outcomes were excess resection volume and clear margin status, and secondary outcome was re-excision rate. 66 patients underwent USG. In the CON group (n = 68), PAG was performed in 24 (35 %) and WIG in 44 (64 %) patients. Median excision volume [39 (IQR 20-66) vs 56 (38-94) cm(3); p = 0.001] and median calculated resection ratio [1.7 (1.0-2.9) vs 2.8 (1.4-4.6) (p = 0.005)] were significantly smaller in the USG than in the CON group. Median minimal distance to the resection margin [4 mm (IQR 2-5 mm) vs 2 mm (1-4 mm), p = 0.004] was significantly larger. Clear resection margins were achieved in 58 of the USG patients (88 %) and in 58 of the CON patients (86 %) (p = 0.91); this was true in patients with palpable as well as nonpalpable lesions. Reexcision was needed in 6.1 and 7.2 % respectively. Relative risk for re-excision in the USG group was 0.82 (95 % CI 0.23-2.93). In patients with palpable and nonpalpable breast cancers, USG allows for lower excision volume and reduced resection of healthy breast tissue, without increased re-excision rate.

Breast cancer subtypes: morphologic and biologic characterization

Advances in basic science, technology and translational research have created a revolution in breast cancer diagnosis and therapy. Researchers' discoveries of genes defining variability in response to therapy and heterogeneity in clinical presentations and tumor biology are the foundation of the path to personalized medicine. The success of personalized breast cancer care depends on access to pertinent clinical information and risk factors, optimal imaging findings, well-established morphologic features, and traditional and contemporary prognostic/predictive testing. The integration of these entities provides an opportunity to identify patients who can benefit from specific therapies, and demonstrates the link between breast cancer subtypes and their association with different tumor biology. It is critical to recognize specific types of breast cancer in individual patients and design optimal personalized therapy. This article will highlight the roles of morphologic features and established tumor biomarkers on patient outcome.

Comparative accuracy of preoperative tumor size assessment on mammography, sonography, and MRI: Is the accuracy affected by breast density or cancer subtype?

PURPOSE

To compare the accuracy of preoperative breast tumor size measurements obtained on three imaging modalities (mammography [MM], sonography [US], and MRI) with those obtained on final pathologic examination for different breast densities and various tumor types.

METHODS

Records from patients who underwent breast cancer lumpectomy between 2008 and 2012 and in whom tumor was seen on all three imaging modalities were retrospectively reviewed for maximum tumor size measurements. Patients with positive tumor margins and those who had undergone neoadjuvant chemotherapy were excluded. Tumor size measurements obtained on the three imaging modalities were compared for accuracy with those obtained during the final pathologic examination. Differences were analyzed for the whole group and for subgroups according to breast density and tumor type.

RESULTS

In total, 57 patients were included, in whom wire-localization lumpectomy was performed without neoadjuvant chemotherapy; negative surgical margins for tumor were obtained, and tumor was preoperatively visualized on all three imaging modalities. The mean (± SEM) tumor size measured on MRI was significantly greater than that measured on pathology (p < 0.001), whereas the sizes measured on US and MM were not statistically significantly different from that measured on pathology (p = 0.62 and p = 0.57). Tumor size measured on MRI was greater than that measured on both US and MM (p = 0.003 and p < 0.001). Compared with the measurements obtained on pathology, that obtained on US showed moderate agreement (Lin concordance correlation coefficient [CCC], 0.71; 95% confidence interval [CI], 0.56-0.82); poorer agreement was found for the sizes obtained on MM (CCC, 0.58; 95% CI, 0.38-0.72) and MRI (CCC, 0.50; 95% CI, 0.31-0.65). No difference in comparative accuracy of size measurement was noted between dense and nondense breast tissue. MRI overestimated tumor size in ductal cancers (p < 0.001) and slightly underestimated it in lobular cancers.

CONCLUSIONS

Preoperative MRI significantly overestimated tumor size. Measurements obtained on US and MM were more accurate irrespective of breast density, with US measurements being slightly more accurate than MM measurements.

Lobular breast cancer series: imaging

The limitations of mammography in the detection and evaluation of invasive lobular carcinoma (ILC) have long been recognized, presenting real clinical challenges in treatment planning for these tumors. However, advances in mammography, ultrasound, and magnetic resonance imaging present opportunities to improve the diagnosis and preoperative assessment of ILC. The evidence supporting the performance of each imaging modality will be reviewed, specifically as it relates to the pathology of ILC and its subtypes. Further, we will discuss emerging technologies that may be employed to enhance the detection rate and ultimately result in more effective screening and staging of ILC.

Value of shear-wave elastography in the diagnosis of symptomatic invasive lobular breast cancer

AIM

To investigate the contribution of shear-wave elastography (SWE) in diagnosing invasive lobular breast cancer (ILC) in symptomatic patients.

MATERIALS AND METHODS

A retrospective case-controlled study of 52 patients with ILC and 52 patients with invasive ductal cancer (IDC), matched for age and tumour size, was performed. Breast density and mammographic and greyscale ultrasound features were graded using Breast Imaging-Reporting and Data System (BI-RADS) classification by two radiologists, blinded to SWE and pathology findings. Forty-four benign lesions were also included. The sensitivity of SWE was assessed, using a cut-off value of 50 kPa for mean elasticity. Statistical significance was evaluated using Chi-square and Chi-square for trend tests.

RESULTS

Mean age for both ILC and IDC groups was 67 years. Mean size for ILC was 44 mm and IDC was 37 mm. The sensitivity for detection of ILC and IDC for mammography, greyscale ultrasound, and SWE were 79% versus 87%, 87% versus 98%, 94% versus 100%, respectively. SWE had significantly higher sensitivities than mammography for the detection of both ILC and IDC (p = 0.012 and p = 0.001, respectively). SWE was not significantly more sensitive than greyscale ultrasound for the detection of either tumour type. Four (8%) lobular cancers were benign/normal at both mammography and greyscale ultrasound, but suspicious on SWE. The incremental gain in sensitivity by using SWE in ILC was statistically significant compared to IDC (p = 0.01).

CONCLUSION

SWE can diagnose lobular cancers that have benign/normal findings on conventional imaging as suspicious.

Magnetic resonance imaging in breast cancer: A literature review and future perspectives

Early detection and diagnosis of breast cancer are essential for successful treatment. Currently mammography and ultrasound are the basic imaging techniques for the detection and localization of breast tumors. The low sensitivity and specificity of these imaging tools resulted in a demand for new imaging modalities and breast magnetic resonance imaging (MRI) has become increasingly important in the detection and delineation of breast cancer in daily practice. However, the clinical benefits of the use of pre-operative MRI in women with newly diagnosed breast cancer is still a matter of debate. The main additional diagnostic value of MRI relies on specific situations such as detecting multifocal, multicentric or contralateral disease unrecognized on conventional assessment (particularly in patients diagnosed with invasive lobular carcinoma), assessing the response to neoadjuvant chemotherapy, detection of cancer in dense breast tissue, recognition of an occult primary breast cancer in patients presenting with cancer metastasis in axillary lymph nodes, among others. Nevertheless, the development of new MRI technologies such as diffusion-weighted imaging, proton spectroscopy and higher field strength 7.0 T imaging offer a new perspective in providing additional information in breast abnormalities. We conducted an expert literature review on the value of breast MRI in diagnosing and staging breast cancer, as well as the future potentials of new MRI technologies.

Nonmasslike lesions on breast sonography: comparison between benign and malignant lesions

OBJECTIVES

To compare the imaging and clinical features of benign and malignant nonmasslike lesions in the breast.

METHODS

During a 2-year period at a single institution, 186 nonmasslike lesions in 158 women were pathologically confirmed through surgery or sonographically guided biopsy. The sonographic patterns (mottled, geographic, and indistinct) and distributions (focal and regional) were compared between benign and malignant lesions. The presence of sonographically visible calcifications, amount of color Doppler signals, presence of positive findings on mammography, and presence of symptoms were also compared between the two groups.

RESULTS

A total of 156 lesions (84%) were confirmed as benign and 30 (16%) as malignant. On sonography, malignant nonmasslike lesions more frequently had mottled and geographic patterns and regional distribution than benign lesions (P < .0001). Malignant lesions also more frequently had sonographically visible calcifications (40% versus 0%; P < 0.0001) and a greater amount of color Doppler signals than benign lesions (P < .0001). On mammography, malignant lesions more frequently had densities and calcifications than benign lesions (30.4% versus 7.1%; P = 0.0052; 73.9% versus 6.1%; P < .0001, respectively). Clinically, malignant lesions were more frequently palpable and accompanied by localized pain than benign lesions (50% versus 2.6%; P< .0001; 13.3% versus 0.6%; P = .0025).

CONCLUSIONS

The imaging and clinical features of malignant nonmasslike lesions differed significantly from those of benign nonmasslike lesions.

Invasive ductolobular carcinoma of the breast: spectrum of mammographic, ultrasound and magnetic resonance imaging findings correlated with proportion of the lobular component

Purpose

The aim of this study was to describe the imaging features of patients with invasive ductolobular carcinoma of the breast in comparison with the proportion of the lobular component.

Materials and methods

We retrospectively reviewed mammographic, sonographic and MRI records of 113 patients with proven ductolobular carcinoma diagnosed between January 2008 and October 2012 according to the BI-RADS ® lexicon, and correlated these to the proportion of the lobular component.

Results

At mammography the most common finding (62.9%) for invasive ductolobular carcinoma was an irregular, spiculated and isodense mass. On ultrasound an irregular and hypoechoic mass, with spiculated margins and posterior acoustic shadowing was observed in 46.8% of cases. Isolated mass and mass associated with non-mass like enhancement (NMLE) were the most common findings by MRI (89.4%). Washout pattern in delayed phase was seen in 61.2% and plateau curve was more frequently observed in patients with larger lobular component. Additional malignant findings (multifocality, multicentricity and contralateral disease) did not correlate significantly with the proportion of the lobular component.

Conclusion

Invasive ductolobular carcinoma mainly presents as an irregular, spiculated mass, isodense on mammography and hypoechoic with posterior acoustic shadowing. On MRI it is usually seen as an isolated mass or as a dominant mass surrounded by smaller masses or NMLE. Washout is the most ordinary kinetic pattern of these tumors. In general, the imaging characteristics did not vary significantly with the proportion of the lobular component.

Prospective MRI assessment for invasive lobular breast cancer. Correlation with tumour size at histopathology and influence on surgical management

AIM

To evaluate the performance of breast magnetic resonance imaging (MRI) in determining the size of invasive lobular carcinoma (ILC) compared to histopathology, and its influence on breast surgical management.

MATERIALS AND METHODS

Prospective evaluation was undertaken of standardized contrast-enhanced MRI images of 51 consecutive women over an 18 month period with pure ILC or with lobular features as the dominant subtype on breast core biopsy. Image interpretation was performed by one consultant radiologist (M.H.). The lesion size at MRI was compared with the size at final histopathology after surgical excision using a Bland-Altman agreement plot.

RESULTS

Of the 51 prospectively imaged consecutive women, seven were excluded as they had diffuse ILC. The remaining 44 patients had a mean histological tumour size of 34.9 mm (range 4-77 mm). MRI underestimated tumour size in 26 (59.1%) cases. In 21 (47.7%) patients, this discrepancy was small, ranging up to 16 mm. The largest underestimation occurred in five (11.4%) cases with a difference ranging between 31 and 48 mm. Fifteen (34.1%) tumours were overestimated by MRI where the discrepancy ranged up to 22 mm. In three (6.8%) patients MRI and histological size matched. The Bland-Altman agreement plot demonstrated that in 95% of cases the size at histopathology will be between 0.36 and 2.31 times the MRI size at extremes. MRI correlated better with histopathology in tumours up to T2 (<5 cm) size leading to a change in surgical management for nine of the 44 (20.5%) patients.

CONCLUSION

MRI enables surgical management decisions to be made with increased confidence in patients with ILC up to T2 size.

Measurement of tumour size with mammography, sonography and magnetic resonance imaging as compared to histological tumour size in primary breast cancer

Background

Tumour size in breast cancer influences therapeutic decisions. The purpose of this study was to evaluate sizing of primary breast cancer using mammography, sonography and magnetic resonance imaging (MRI) and thereby establish which imaging method most accurately corresponds with the size of the histological result.

Methods

Data from 121 patients with primary breast cancer were analysed in a retrospective study. The results were divided into the groups “ductal carcinoma in situ (DCIS)”, invasive ductal carcinoma (IDC) + ductal carcinoma in situ (DCIS)”, “invasive ductal carcinoma (IDC)”, “invasive lobular carcinoma (ILC)” and “other tumours” (tubular, medullary, mucinous and papillary breast cancer). The largest tumour diameter was chosen as the sizing reference in each case. Bland-Altman analysis was used to determine to what extent the imaging tumour size correlated with the histopathological tumour sizes.

Results

Tumour size was found to be significantly underestimated with sonography, especially for the tumour groups IDC + DCIS, IDC and ILC. The greatest difference between sonographic sizing and actual histological tumour size was found with invasive lobular breast cancer. There was no significant difference between mammographic and histological sizing. MRI overestimated non-significantly the tumour size and is superior to the other imaging techniques in sizing of IDC + DCIS and ILC.

Conclusions

The histological subtype should be included in imaging interpretation for planning surgery in order to estimate the histological tumour size as accurately as possible.

Imaging features of breast malignancy: breast ultrasound and MR imaging correlation

Recent advances in breast imaging, including volumetric breast ultrasound and breast magnetic resonance (MR) imaging, now provide multiplanar capability for detailed morphologic assessment of breast malignancies. This article describes the imaging findings of common breast cancers, utilizing volumetric breast ultrasound with MR imaging correlation. Knowledge of the characteristic appearances of breast malignancy can facilitate the diagnosis and management of breast masses, particularly when obscured by excessive breast density on mammography examinations.

Are the imaging features of the pleomorphic variant of invasive lobular carcinoma different from classic ILC of the breast?

The aim of this study was to evaluate whether pleomorphic invasive lobular carcinoma (PILC) is different from classic invasive lobular carcinoma (CILC) in terms of radiologic and clinicopathologic features. We compared the radiologic and clinicopathologic features of 22 surgically confirmed PILCs in 21 patients from 2004 to 2009 and 47 CILCs from 47 consecutive patients. For all cases, we reviewed the imaging findings, medical records and pathological results. PILC had a higher T stage, N stage, nuclear and histologic grade compared to CILC. PILC was more commonly negative for estrogen receptors and positive for HER2 than CILC (all p < 0.05). However, there were no significant differences in age, symptoms, tumor size, extensive intraductal component, lymphovascular invasion, triple negative profile, or multiplicity between the two groups. PILC was not detected on mammography in 1 (4.5%) of 22 cases, whereas CILC was not detected on mammography in 7 (14.9%) of 47 cases and on MRI in 2 (5.0%) of 40 (p = 0.42 and p = 1.000, respectively). MRI identified more frequent multiplicity than mammography for both PILC and CILC (p < 0.001), but was similar to US (p = 0.066). Most lesions showed a spiculated mass or architectural distortion with or without calcifications on mammography and ultrasound. No differences in mass and/or non-mass lesions or kinetics on MRI were observed between the two groups. PILC shows more pathologically aggressive features, but cannot be differentiated from CILC based on imaging findings.

Sonomammographic characteristics of invasive lobular carcinoma

OBJECTIVE

The objective of our study was to identify characteristic features of invasive lobular carcinoma on mammography and ultrasound examinations.

MATERIALS AND METHODS

This is a retrospective multicenter study of women with biopsy-proven invasive lobular carcinoma. All patients had undergone diagnostic sonomammography. The imaging findings were identified by experienced breast imagers. Final surgical pathology results were used as the reference standard.

RESULTS

Thirty-two women ranging in age from 42 to 63 years old (mean age, 53 years), All had biopsy-proven invasive lobular carcinomas. Common features on mammogram included dense mass followed by architectural distortion; three cases showed breast asymmetry and one case was reported as normal. On ultrasound, common features included solid mass with spiculated margins, posterior shadowing, and perpendicular to the skin.

CONCLUSION

Although no specific features could be linked to invasive lobular carcinoma, care should be directed to subtle signs such as architectural distortion and breast asymmetry in order not to miss any lesions. The combination of mammographic and sonographic helps to decrease the relatively high false negative diagnosis of this type of breast cancer.

Imaging features of invasive lobular carcinoma: comparison with invasive ductal carcinoma

PURPOSE

The aim of this study was to evaluate the imaging findings of invasive lobular carcinoma (ILC) compared to those of invasive ductal carcinoma (IDC).

MATERIALS AND METHODS

The study included ILCs (n = 27) and IDCs (n = 85). Imaging findings were retrospectively evaluated, according to the BI-RADS lexicon. We compared the imaging findings, multiplicity, and magnetic resonance imaging (MRI) detection accuracy of ILC with those of IDC.

RESULTS

At mammography, normal findings and mass lesions were more frequent with ILCs (14.8% and 59.2%, respectively) than with IDCs (1.2% and 44.7%, respectively) (P = 0.009). With ultrasonography (US), posterior acoustic shadowing was more frequently seen in ILCs (59.2%) than in IDCs (15.8%) (P < 0.001). With MRI, both ILCs and IDCs most commonly appeared as a heterogeneously enhancing, irregular mass with a spiculated border. Multifocality was more frequently associated with ILCs (40.7%) than with IDCs (14.1% 1% 0.002). However, multicentricity and bilaterality were not different between the two groups. The sensitivity and specificity of MRI for the detection of multiplicity were 91.6% and 73.3%, respectively, for ILCs and 83.3% and 80.3%, respectively, for IDCs.

CONCLUSION

Normal findings, mass lesions on mammography, and posterior acoustic shadowing on US were more frequently associated with ILCs than with IDCs. Multifocality was more prevalent with ILCs than with IDCs.

[Modern gray-scale sonography of the breast]

Recently, the diagnosis of breast diseases by ultrasound has changed radically. It is no longer a complementary modality to mammography but a separate method to investigate breast disease. Innovative high-resolution ultrasound allows more specific diagnosis of breast tumors. Tissue-harmonic imaging not only uses the transmitted, fundamental frequency to obtain an image but also the harmonic frequency. The harmonic signal is processed by the ultrasound system with the result of better delineation of tissue structures and spatial compounding assembles an image from multiple images taken from different angles of echo waves. The effect is the reduction of artifacts with optimized contrast. Finally the advanced speckle reduction technique is used to smooth and homogenize the image. Additionally continuous advancement of new high-resolution linear transducers is responsible for the essential improvement of image quality. In conclusion, it is recommended to integrate all of the described modalities in order to obtain diagnostically conclusive image quality. This article demonstrates the new techniques and applications exemplified using images.

Diffuse infiltrative lesion of the breast: clinical and radiologic features

The purpose of this paper is to show the clinical and radiologic features of a variety of diffuse, infiltrative breast lesions, as well to review the relevant literature. Radiologists must be familiar with the various conditions that can diffusely involve the breast, including normal physiologic changes, benign disease and malignant neoplasm.