The Effectiveness of MR Imaging in the Assessment of Invasive Lobular Carcinoma of the Breast

Is staging breast magnetic resonance imaging for invasive lobular carcinoma worthwhile?

BACKGROUND

Invasive lobular carcinoma (ILC) is challenging to stage accurately using mammography (MG) and ultrasound (US) with undiagnosed ipsilateral and contralateral cancer resulting in poor patient outcomes including return to surgery. Our institution employs routine staging breast MRI in ILC for this reason. However, increased time for further imaging/biopsies contributes to patient anxiety and potentially delays definite management. We aimed to quantify the frequency of staging MRI-detected additional lesions requiring biopsy or follow-up, the added cancer detection rate and MRI prompted change in surgical management.

METHODS

An observational study on staging breast MRI for newly diagnosed ILC at a tertiary Western Australian hospital from January 2019 to August 2022. Standardized 3T MRI protocol was performed, double read by unblinded fellowship-trained radiologists. Histopathology from biopsy, surgery, or first annual surveillance was the reference standard for additional MRI-detected lesions.

RESULTS

One hundred ten MRI studies demonstrated 49 (45%) patients had at least one additional clinically significant MRI-detected lesion. Thirty-one patients had an additional ipsilateral lesion detected, of which 18 (58%) proved malignant; 14 (45%) multifocal and 4 (13%) multicentric ILC. Additional work-up of MRI-detected lesions averaged a 9-day delay to definitive surgery compared to patients with a negative or definitively benign MRI. MRI changed surgical planning in 11 of 110 cases from breast conservation surgery (BCS) to mastectomy and there were two contralateral cancers diagnosed. BCS reoperation rate was 11%.

CONCLUSION

Staging MRI for ILC identifies clinically significant lesions in nearly half of patients, predominantly ipsilateral multifocal disease, without significant delay to definitive surgery.

Correlations of Imaging and Therapy in Breast Cancer Based on Molecular Patterns: An Important Issue in the Diagnosis of Breast Cancer

Breast cancer is a global health issue affecting countries worldwide, imposing a significant economic burden due to expensive treatments and medical procedures, given the increasing incidence. In this review, our focus is on exploring the distinct imaging features of known molecular subtypes of breast cancer, underlining correlations observed in clinical practice and reported in recent studies. The imaging investigations used for assessment include screening modalities such as mammography and ultrasonography, as well as more complex investigations like MRI, which offers high sensitivity for loco-regional evaluation, and PET, which determines tumor metabolic activity using radioactive tracers. The purpose of this review is to provide a better understanding as well as a revision of the imaging differences exhibited by the molecular subtypes and histopathological types of breast cancer.

The Role of Magnetic Resonance Imaging in the Preoperative Staging and Treatment of Invasive Lobular Carcinoma

INTRODUCTION

Invasive lobular carcinoma (ILC) is known for its diffuse growth pattern and its associated challenges in diagnosing. Magnetic resonance imaging (MRI) is the most accurate imaging modality and might aid in improving preoperative staging compared to full field digital mammography (FFDM) and ultrasound (US), however current literature is inconsistent. The aim of this paper is to evaluate the accuracy of MRI staging compared to FFDM/US and pathology results.

METHODS

In this single-centre retrospective study, all patients diagnosed with ILC between 2014 and 2019 who underwent preoperative MRI were included. Specific parameters studied were: (1) the need for second-look targeted biopsies, (2) detection of new tumors (ie, contralateral or multifocal), (3) changes in cTNM-classification, and (4) impact on final treatment plan. Bland-Altman plots were used to compare the tumor sizes measured on MRI and FFDM/US with actual pathological tumor sizes.

RESULTS

Ninety-nine patients were included. After performing preoperative MRI, 9 (9.1%) multifocal tumors were diagnosed after additional biopsies. Contralateral tumors were detected twice (2.0%) and cN classification was upgraded in 7 cases (7.1%). Surgical treatment or neoadjuvant treatment plans were changed in 16 patients (16.1%). Compared to histopathological results, FFDM/US underestimated tumor size with a mean of 0.4 cm (Limit of agreement (LoA): -2.8 cm to 2.0 cm) whereas MRI overestimated tumor size with a mean of 0.6 cm (LoA: -1.9 cm to 3.0 cm).

CONCLUSIONS

In our study, mean differences in tumor size measurements using FFDM/US and MRI were comparable, with similar random errors. MRI correctly diagnosed multifocal and contralateral tumors more often and provided a better cN staging.

Impact of pre-operative MRI on surgical management of screening digital breast tomosynthesis-detected invasive lobular carcinoma

PURPOSE

The purpose of this study is to determine the impact of pre-operative MRI on surgical management of screening digital breast tomosynthesis (DBT)-detected invasive lobular carcinoma (ILC).

METHODS

A retrospective medical record analysis was conducted of women with screening DBT-detected ILC and subsequent surgery from 2017-2021. Clinical, imaging, and pathological features were compared between women who did and did not undergo MRI, and between women with and without additional disease detected on MRI, using the Pearson's chi-squared test and Wilcoxon signed-rank test. Concordance between imaging and surgical pathology sizes was also evaluated.

RESULTS

Of 125 women (mean age 67 years, range 44-90) with screening-detected ILC, MRI was obtained in 62 women (49.6%) with a mean age of 63 years (range 45-80). Compared to women without MRI, women who had MRI examinations were younger, more likely to have dense breast tissue, and more likely to undergo mastectomy initially rather than lumpectomy (p < 0.001-0.01). Eighteen biopsies were performed based on MRI findings, of which 55.6% (10/18) were malignant. Conventional imaging more frequently underestimated ILC span at the biopsy site than MRI, using a 25% threshold difference (17.5% [7/40] versus 58.5% [24/41], p < 0.001). MRI detected more extensive disease at the biopsy site in six patients (9.7%, 6/62), additional ipsilateral disease in six patients (9.7%, 6/62), and contralateral disease in one patient (1.6%, 1/62). MRI therefore impacted surgical management in 21.0% (13/62) of patients.

CONCLUSION

MRI led to the detection of additional disease, thus impacting surgical management, in one-fifth of patients with 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.

The Impact of Preoperative Breast MRI on Timing of Surgical Management in Newly Diagnosed Breast Cancer

Purpose: Preoperative breast MRI has been recommended at our center since 2016 for invasive lobular carcinoma and cancers in dense breasts. This study examined how preoperative breast MRI impacted surgical timing and outcomes for patients with newly diagnosed breast cancer. Methods: Retrospective single-center study of consecutive women diagnosed with new breast cancer between June 1, 2019, and March 1, 2021, in whom preoperative breast MRI was recommended. MRI, tumor histology, breast density, post-MRI biopsy, positive predictive value of biopsy (PPV3), surgery, and margin status were recorded. Time from diagnosis to surgery was compared using t-tests. Results: There were 1054 patients reviewed, and 356 were included (mean age 60.9). Of these, 44.4% (158/356) underwent preoperative breast MRI, and 55.6% (198/356) did not. MRI referral was more likely for invasive lobular carcinoma, multifocal disease, and younger patients. Following preoperative MRI, 29.1% (46/158) patients required additional breast biopsies before surgery, for a PPV3 of 37% (17/46). The time between biopsy and surgery was 55.8 ± 21.4 days for patients with the MRI, compared to 42.8 ± 20.3 days for those without (P < .00001). MRI was not associated with the type of surgery (mastectomy vs breastconserving surgery) (P = .44) or rate of positive surgical margins (P = .52). Conclusion: Among patients who underwent preoperative breast MRI, we observed significant delays to surgery by almost 2 weeks. When preoperative MRI is requested, efforts should be made to mitigate associated delays.

Molecular Breast Imaging and Positron Emission Mammography

There is growing interest in application of functional imaging modalities for adjunct breast imaging due to their unique ability to evaluate molecular/pathophysiologic changes, not visible by standard anatomic breast imaging. This has led to increased use of nuclear medicine dedicated breast-specific single photon and coincidence imaging systems for multiple indications, such as supplemental screening, staging of newly diagnosed breast cancer, evaluation of response to neoadjuvant treatment, diagnosis of local disease recurrence in the breast, and problem solving. Studies show that these systems maybe especially useful for specific subsets of patients, not well served by available anatomic breast imaging modalities.

Is Choosing Wisely Wise for Lobular Carcinoma in Patients Over 70 Years of Age? A National Cancer Database Analysis of Sentinel Node Practice Patterns

BACKGROUND

Controversy continues in the treatment of breast cancer in women over 70 years of age. In 2016, the Society of Surgical Oncology recommended against routine use of sentinel lymph node biopsy (SLNBx) as part of the 'Choosing Wisely Campaign'. This study examines the oncologic safety of avoidance of routine SLNBx in patients over 70 years of age with invasive lobular carcinoma (ILC).

METHODS

The National Cancer Database was used to identify women with invasive ductal carcinoma (IDC) and ILC diagnosed between 2012 and 2020. Clinical and pathological staging, axillary staging, surgery type, and lymph node positivity between patients with IDC or ILC were compared.

RESULTS

Among women with T1 tumors, 85,949 (79.6%) patients with IDC and 12,761 (81.5%) patients with ILC underwent SLNBx (p < 0.001). Among patients who underwent SLNBx, those with IDC were more likely to have positive nodes (n = 7535, 8.8%) than those with ILC (n = 1041, 8.2%; p = 0.02). During the time interval of interest, for both IDC and ILC patients, the rate of axillary lymph node dissection decreased and rates of SLNBx or no axillary staging increased. On multivariate analysis, ILC histology was associated with use of SLNBx, but without nodal positivity.

CONCLUSION

A trend de-escalation of axillary staging was identified in this study, however the majority of patients meeting the 'Choosing Wisely' criteria are still undergoing SLNBx. No increased risk of nodal positivity was identified among patients with ILC, suggesting that surgeons can continue to choose wisely and limit the use of SLNBx in women over 70 years of age with T1 ILC tumors.

Classifying invasive lobular carcinoma as special type breast cancer may be reducing its treatment success: A comparison of survival among invasive lobular carcinoma, invasive ductal carcinoma, and no-lobular special type breast cancer

PURPOSE

The literature contains different information about the prognosis of invasive lobular carcinoma of breast cancer (BC). We aimed to address the inconsistency by comparatively examining the clinical features and prognosis of invasive lobular carcinoma patients in our university and to report our experience by dividing our patients into various subgroups.

PATIENTS AND METHODS

Records of patients with BC admitted to Trakya University School of Medicine Department of Oncology between July 1999 and December 2021 were reviewed. The patients were divided into three groups (No-Special Type BC, Invasive Lobular Special Type BC, No-Lobular Special Type BC). Patient characteristics, treatment methods and oncological results are presented. Survival curves were generated using the Kaplan-Meier method. Statistical significance of survival among the selected variables was compared by using the log-rank test.

RESULTS

The patients in our study consisted of 2142 female and 15 male BC patients. There were 1814 patients with No-Special Type BC, 193 patients with Invasive Lobular Special Type BC, and 150 patients with No-Lobular Special Type BC. The duration of disease-free survival (DFS) was 226.5 months for the No-Special Type BC group, 216.7 months for the No-Lobular Special Type BC group, and 197.2 months for the Invasive Lobular Special Type BC group, whereas the duration of overall survival (OS) was 233.2 months for the No-Special Type BC group, 227.9 for the No-Lobular Special Type BC group, and 209.8 for the Invasive Lobular Special Type BC group. The duration of both DFS and OS was the lowest in the Invasive Lobular Special Type BC group. Multivariate factors that were significant risk factors for OS were Invasive Lobular Special Type BC histopathology (p = .045), T stage, N stage, stage, skin infiltration, positive surgical margins, high histological grade, and mitotic index. Modified radical mastectomy, chemotherapy, radiotherapy and use of tamoxifen and aromatase inhibitors for more than 5 years were significant protective factors for overall survival.

CONCLUSION

The histopathological subgroup with the worst prognosis in our study was Invasive Lobular Special Type BC. Duration of DFS and OS were significantly shorter in Invasive Lobular Special Type BC than No-Lobular Special Type BC group. The classification of Invasive Lobular BC under the title of Special Type BC should be reconsidered and a more accurate treatment and follow-up process may be required.

ACR Appropriateness Criteria® Monitoring Response to Neoadjuvant Systemic Therapy for Breast Cancer: 2022 Update

Imaging plays a vital role in managing patients undergoing neoadjuvant chemotherapy, as treatment decisions rely heavily on accurate assessment of response to therapy. This document provides evidence-based guidelines for imaging breast cancer before, during, and after initiation of neoadjuvant chemotherapy. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Preoperative Breast MRI: Current Evidence and Patient Selection

Breast MRI is the most sensitive imaging modality for the assessment of newly diagnosed breast cancer extent and can detect additional mammographically and clinically occult breast cancers in the ipsilateral and contralateral breasts. Nonetheless, appropriate use of breast MRI in the setting of newly diagnosed breast cancer remains debated. Though highly sensitive, MRI is less specific and may result in false positives and overestimation of disease when MRI findings are not biopsied prior to surgical excision. Furthermore, improved anatomic depiction of breast cancer on MRI has not consistently translated to improved clinical outcomes, such as lower rates of re-excision or breast cancer recurrence, though there is a paucity of well-designed studies examining these issues. In addition, current treatment paradigms have been developed in the absence of this more accurate depiction of disease span, which likely has limited the value of MRI. These issues have led to inconsistent and variable utilization of preoperative MRI across practice settings and providers. In this review, we discuss the history of breast MRI and its current use and recommendations with a focus on the preoperative setting. We review the evidence surrounding the use of preoperative MRI in the evaluation of breast malignancies and discuss the data on breast MRI in the setting of specific patient factors often used to determine breast MRI eligibility, such as age, index tumor phenotype, and breast density. Finally, we review the impact of breast MRI on surgical outcomes (re-excision and mastectomy rates) and long-term breast recurrence and survival outcomes.

Invasive Lobular Carcinoma: A Review of Imaging Modalities with Special Focus on Pathology Concordance

Invasive lobular cancer (ILC) is the second most common type of breast cancer. It is characterized by a unique growth pattern making it difficult to detect on conventional breast imaging. ILC can be multicentric, multifocal, and bilateral, with a high likelihood of incomplete excision after breast-conserving surgery. We reviewed the conventional as well as newly emerging imaging modalities for detecting and determining the extent of ILC- and compared the main advantages of MRI vs. contrast-enhanced mammogram (CEM). Our review of the literature finds that MRI and CEM clearly surpass conventional breast imaging in terms of sensitivity, specificity, ipsilateral and contralateral cancer detection, concordance, and estimation of tumor size for ILC. Both MRI and CEM have each been shown to enhance surgical outcomes in patients with newly diagnosed ILC that had one of these imaging modalities added to their preoperative workup.

[MRI-Guided Breast Intervention: Biopsy and Needle Localization]

In Korea, the number of institutions providing breast MRI, as well as the number of breast MRIs, has recently increased. However, MRI-guided procedures, including biopsy and needle localization, are rarely performed compared to ultrasound-guided or stereotactic biopsy. As breast MRI has high sensitivity but limited specificity, lesions detected only on MRI require pathologic confirmation through MRI-guided biopsy or surgical excision with MRI-guided needle localization. Thus, we aimed to review MRI-guided procedures, including their indications, techniques, procedural considerations, and limitations.

Evolution of biological features of invasive lobular breast cancer: comparison between primary tumor and metastases

BACKGROUND

Invasive lobular carcinoma (ILC) has unique clinical-biological features. Phenotypical differences between primary tumours (PTs) and metastases (M) have been described for invasive ductal carcinoma, but data on ILC are limited.

METHODS

We retrospectively analysed patients with recurrent ILC from our institution from 2013 to 2020. We evaluated the discordance of the oestrogen receptor (ER), progesterone receptor (PgR) and HER2 between PT and M, to understand prognostic and therapeutic implications.

RESULTS

Thirteen percent (n = 91) of all patients had ILC. We observed 15%, 44% and 5% of ER, PgR and HER2 status discordance between PT and M. ER/PgR discordance was related to receptor loss and HER2 mainly due to gain. PT presented a luminal-like phenotype (93%); 6% and 1% were triple-negative (TNBC) and HER2-positive. In M, there was an increase in TNBC (16%) and HER2-positive (5%). Metastasis-free survival and overall survival (OS) were different according to clinical phenotype, with poorer prognosis for HER2+ and TNBC (p < 0.001); OS after metastatic progression did not differ across phenotypes (p = 0.079). In luminal-like ILC (n = 85) at diagnosis, we found that OS after relapse was poorer in patients experiencing a phenotype switch to TNBC but improved in patients with HER2 gain (p = 0.0028). Poorer survival was reported in patients with a PgR and/or ER expression loss of ≥25%. There was HER2-low enrichment in M1 (from 37% to 58%): this change was not associated with OS (p > 0.05).

CONCLUSION

Our results suggest that phenotype switch after metastatic progression may be associated with patients' outcomes. Tumour biopsy in recurrent ILC could drive treatment decision-making, with prognostic implications.

Surgical Planning after Neoadjuvant Treatment in Breast Cancer: A Multimodality Imaging-Based Approach Focused on MRI

Neoadjuvant chemotherapy (NACT) today represents a cornerstone in the treatment of locally advanced breast cancer and highly chemo-sensitive tumors at early stages, increasing the possibilities of performing more conservative treatments and improving long term outcomes. Imaging has a fundamental role in the staging and prediction of the response to NACT, thus aiding surgical planning and avoiding overtreatment. In this review, we first examine and compare the role of conventional and advanced imaging techniques in preoperative T Staging after NACT and in the evaluation of lymph node involvement. In the second part, we analyze the different surgical approaches, discussing the role of axillary surgery, as well as the possibility of non-operative management after-NACT, which has been the subject of recent trials. Finally, we focus on emerging techniques that will change the diagnostic assessment of breast cancer in the near future.

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.

Diagnostic Challenge of Invasive Lobular Carcinoma of the Breast: What Is the News? Breast Magnetic Resonance Imaging and Emerging Role of Contrast-Enhanced Spectral Mammography

Invasive lobular carcinoma is the second most common histologic form of breast cancer, representing 5% to 15% of all invasive breast cancers. Due to an insidious proliferative pattern, invasive lobular carcinoma remains clinically and radiologically elusive in many cases. Breast magnetic resonance imaging (MR) is considered the most accurate imaging modality in detecting and staging invasive lobular carcinoma and it is strongly recommended in pre-operative planning for all ILC. Contrast-enhanced spectral mammography (CESM) is a new diagnostic method that enables the accurate detection of malignant breast lesions similar to that of breast MR. CESM is also a promising breast imaging method for planning surgeries. In this study, we compare the ability of contrast-enhanced spectral mammography (CESM) with breast MR in the preoperative assessment of the extent of invasive lobular carcinoma. All patients with proven invasive lobular carcinoma treated in our breast cancer center underwent preoperative breast MRI and CESM. Images were reviewed by two dedicated breast radiologists and results were compared to the reference standard histopathology. CESM was similar and in some cases more accurate than breast MR in assessing the extent of disease in invasive lobular cancers. Further evaluation in larger prospective randomized trials is needed to validate our preliminary results.

Accuracy of Preoperative Breast MRI Versus Conventional Imaging in Measuring Pathologic Extent of Invasive Lobular Carcinoma

OBJECTIVE

To determine whether invasive lobular carcinoma (ILC) extent is more accurately depicted with preoperative MRI (pMRI) than conventional imaging (mammography and/or ultrasound).

METHODS

After IRB approval, we retrospectively identified women with pMRIs (February 2005 to January 2014) to evaluate pure ILC excluding those with ipsilateral pMRI BI-RADS 4 or 5 findings or who had neoadjuvant chemotherapy. Agreement between imaging and pathology sizes was summarized using Bland-Altman plots, absolute and percent differences, and the intraclass correlation coefficient (ICC). Rates of underestimation and overestimation were evaluated and their associations with clinical features were explored.

RESULTS

Among the 56 women included, pMRI demonstrated better agreement with pathology than conventional imaging by mean absolute difference (1.6 mm versus -7.8 mm, P < 0.001), percent difference (10.3% versus -16.4%, P < 0.001), and ICC (0.88 versus 0.61, P = 0.019). Conventional imaging more frequently underestimated ILC span than pMRI using a 5 mm difference threshold (24/56 (43%) versus 10/56 (18%), P < 0.001), a 25% threshold (19/53 (36%) versus 10/53 (19%), P = 0.035), and T category change (17/56 (30%) versus 7/56 (13%), P = 0.006). Imaging-pathology size concordance was greater for MRI-described solitary masses than other lesions for both MRI and conventional imaging (P < 0.05). Variability of conventional imaging was lower for patients ≥ the median age of 62 years than for younger patients (SD: 12 mm versus 22 mm, P = 0.012).

CONCLUSION

MRI depicts pure ILC more accurately than conventional imaging and may have particular value for younger women.

Is staging breast magnetic resonance imaging prompted upgrade to mastectomy appropriate?

BACKGROUND

Breast magnetic resonance imaging (MRI) use for surgical staging is increasing, though remains controversial. We aimed to evaluate the accuracy of MRI in surgical decision-making to determine if mastectomy prompted by MRI was appropriate.

METHODS

A single-centre observational study in Perth, Western Australia, with the inclusion of all preoperative and postoperative studies (e.g. involved margins after breast-conserving surgery) undergoing staging breast MRI from 1 January 2015 to 26 August 2019. A standard protocol using gadolinium contrast was used. The reference standard was postoperative histopathology or, for studies without additional surgery after MRI following breast-conserving surgery, the next and subsequent annual screening episodes. By reviewing the final histopathology, the medical case notes and multidisciplinary team decision process, we evaluated whether the reported MRI disease extent was accurate in prompting an appropriate upgrade to mastectomy. Outcomes are reported with descriptive statistics.

RESULTS

Of 130 cancers staged with MRI; seven were excluded as information was incomplete, 104 were performed preoperatively and 19 postoperatively. The majority (60%) staged lobular carcinoma (invasive 59%, in situ 1%) compared to ductal carcinoma (invasive 31%, in situ 8%). For preoperative MRI, half (54% - 56/104) underwent subsequent mastectomy. Of these, MRI prompted mastectomy in 45% (25/56), all appropriate for disease extent. In the postoperative staging group, two mastectomies were performed, one planned before imaging, the other prompted when MRI diagnosed residual disease and confirmed on histopathology. No false-negative staging MRI was identified.

CONCLUSIONS

In our cohort, MRI prompted an upgrade to mastectomy in 21% (26/123), appropriate for cancer extent.

Magnetic Resonance Imaging Features in Different Types of Invasive Breast Cancer: A Systematic Review of the Literature

Breast cancer is the most common malignancy affecting women worldwide, and early diagnosis of breast cancer is the key to its successful and effective treatment. Traditional imaging techniques such as mammography and ultrasound are used to detect and configure breast abnormalities; unfortunately, these modalities have low sensitivity and specificity, particularly in young patients with dense breast tissue, breast implants, or post-surgical scar/architecture distortions. Therefore, breast magnetic resonance imaging (MRI) has been superior in the characterization and detection of breast cancer, especially that with invasive features. This review article explores the importance of breast MRI in the early detection of invasive breast cancer versus traditional tools, including mammography and ultrasound, while also analyzing the use of MRI as a screening tool for high-risk women. We will also discuss the different MRI features for invasive ductal carcinoma and lobular carcinoma and the role of breast MRI in the detection of ductal carcinoma in situ with a focus on the utilization of new techniques, including MR spectroscopy and diffusion-weighted imaging.

Is axillary imaging for invasive lobular carcinoma accurate in determining clinical node staging?

PURPOSE

Preoperative evaluation of clinical N-stage (cN) is difficult in breast cancer patients with invasive lobular carcinoma (ILC). Our goal was to assess the predictive value of axillary imaging in ILC by comparing imaging cN and pathologic N-stage (pN).

METHODS

A single-institution retrospective review was performed for newly diagnosed stage I-III ILC patients undergoing preoperative breast imaging from 2011 to 2016. Clinicopathologic factors; mammogram, MRI, and ultrasound findings; and surgical pathology data were reviewed. Sub-analysis for pN2-N3 patients was performed to determine imaging sensitivity for patients with a larger nodal disease burden. Statistical analysis included sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each imaging modality.

RESULTS

Of the total 349 patients included, 70.5% were cN0, and 62% were pN0 (p = 0.03). For all patients, mammogram sensitivity was 7%, specificity 97%, PPV 50%, NPV 72%; ultrasound sensitivity was 26%, specificity 86%, PPV 52%, NPV 67%; MRI sensitivity was 7%, specificity 98%, PPV 80%, NPV 51%. For pN2/N3 patients, 38% were identified as cN0. Mammogram sensitivity was 10%; ultrasound 42%; MRI 65%. Pathology evaluation of N2/N3 patients indicated LN were replaced with ILC but maintained normal architecture. The average largest pathologic tumor deposit (1.5 ± 0.8 cm) correlated with average largest imaging LN size (1.4 ± 0.6 cm) (p = 0.58).

CONCLUSION

A statistically significant difference between clinical and pathologic N-stage exists for ILC patients. MRI was most sensitive for identification of pN2-N3 patients and should be considered part of routine axillary imaging evaluation for ILC patients.

Pleomorphic Invasive Lobular Carcinoma of the Breast With Extracellular Mucin and HER2 Amplification

Invasive lobular carcinoma with extracellular mucin is an uncommon pattern of invasive breast carcinoma. The 5th Edition of the World Health Organization Classification of Breast Tumors states that it is unknown whether these tumors are a subtype of mucinous carcinoma or invasive lobular carcinoma. Invasive lobular carcinoma with extracellular mucin frequently presents as a palpable mass and may be more likely to be grade 2 to 3 and HER2-positive than classic invasive lobular carcinoma. This case of pleomorphic invasive lobular carcinoma with extracellular mucin was detected by imaging only and was HER2-amplified, suggesting that a subset of these tumors may be clinically occult with an aggressive phenotype. Invasive lobular carcinoma with extracellular mucin is infrequently encountered and awareness of this entity is helpful in avoiding misdiagnosis.

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.

Hereditary diffuse gastric cancer: updated clinical practice guidelines

Hereditary diffuse gastric cancer (HDGC) is an autosomal dominant cancer syndrome that is characterised by a high prevalence of diffuse gastric cancer and lobular breast cancer. It is largely caused by inactivating germline mutations in the tumour suppressor gene CDH1, although pathogenic variants in CTNNA1 occur in a minority of families with HDGC. In this Policy Review, we present updated clinical practice guidelines for HDGC from the International Gastric Cancer Linkage Consortium (IGCLC), which recognise the emerging evidence of variability in gastric cancer risk between families with HDGC, the growing capability of endoscopic and histological surveillance in HDGC, and increased experience of managing long-term sequelae of total gastrectomy in young patients. To redress the balance between the accessibility, cost, and acceptance of genetic testing and the increased identification of pathogenic variant carriers, the HDGC genetic testing criteria have been relaxed, mainly through less restrictive age limits. Prophylactic total gastrectomy remains the recommended option for gastric cancer risk management in pathogenic CDH1 variant carriers. However, there is increasing confidence from the IGCLC that endoscopic surveillance in expert centres can be safely offered to patients who wish to postpone surgery, or to those whose risk of developing gastric cancer is not well defined.

MRI-guided core needle biopsy of the breast: Radiology-pathology correlation and impact on clinical management

OBJECTIVE

Breast MRI is used to screen high-risk patients and determine extent of disease in breast cancer (BC) patients. The goal of this study was to determine the pathologic correlates of breast MRI abnormalities biopsied under MRI guidance.

METHODS

We retrospectively identified 101 MRI-guided core needle biopsies (CNB) of the breast from 79 women over a 4-year period. MRI-detected lesions biopsied with ultrasound or stereotactic guidance were excluded. MRI studies and pathology were reviewed by breast radiologists and pathologists.

RESULTS

Of the 79 patients, 72 (91%) had a history of prior (n = 13) or concurrent (n = 59) BC. There were 101 MRI abnormalities: 60 (59%) with non-mass enhancement (NME) and 41 (41%) with mass enhancement. Pathology was benign in 83/101 (82%), including in the majority of NME lesions (43/60, 72%). The most common benign findings were: fibrocystic changes (FCC) (49%), sclerosing lesions (13%), and fibroadenoma (FA) (9%). There were 18 (18%) malignant diagnoses: 8 (44%) invasive lobular carcinoma (ILC), 7 (39%) ductal carcinoma in situ (DCIS), and 3 (17%) invasive ductal carcinoma (IDC). Of the 18 malignant diagnoses, 16 (89%) occurred in 14 unique patients with concurrent BC. Based on the malignant MRI-guided CNB, 6 (46%) of these patients had additional (sentinel lymph node biopsy or contralateral breast surgery) or more extensive (wider lumpectomy) surgery.

CONCLUSION

In this series, most MRI-guided CNB of the breast were benign. The vast majority of malignant diagnoses occurred in patients with concurrent BC and frequently resulted in changes in clinical management.

Rate of Re-excision after Breast-conserving Surgery for Invasive Lobular Carcinoma

Invasive lobular carcinoma (ILC) accounts for approximately 5 to 20 per cent of all breast cancers and is often multicentric. Despite pre- and intraoperative assessments to achieve negative margins, ILC is reported to be associated with higher rates of positive margin. This cross-sectional study examined patients with breast cancer treated at our institution from 2000 to 2010. The objective was to investigate the rate of re-excision resulting from positive or close margin (1 mm or less) in patients who underwent breast-conserving surgery (BCS) for ILC compared with invasive ductal carcinoma (IDC) and ductal carcinoma in situ (DCIS). Of the 836 patients treated, 416 patients underwent BCS. The rate of re-excision after BCS for ILC was 35.1 versus 17.7 per cent for IDC and 20.0 per cent for DCIS ( P = 0.04). Re-excisions were more often performed for positive margin in patients with ILC (11 of 37 [29.7%]) versus IDC (36 of 334 [10.8%]) and DCIS (five of 45 [11.1%];( P = 0.004). In this single-institution review, BCS for ILC had significantly higher rates of re-excision as a result of positive margins when compared with IDC and DCIS. Tumor size greater than 2 cm and lymph node involvement were identified as factors associated with positive surgical margin in ILC. The higher possibility of positive margins and the need for additional procedures should be discussed with patients undergoing BCS for ILC.

Does Medicare-eligible high-risk breast cancer screening MRI target the right women?

INTRODUCTION

MRI is the most sensitive modality to screen for breast cancer, but it is expensive with somewhat limited access. Audit of screening performance should reflect appropriate population targeting.

METHODS

An observational study on consecutively screened high-risk women, assessment of the contralateral breast staging a new cancer, or surveillance in women with prior breast cancer or high-risk lesion in Perth, Western Australia. All breast MRI studies from 1 January 2015 to 7 September 2018 were included. Studies were 3T comprising T2, DWI, ADC and T1-weighted +/- fat saturation +/- IV gadolinium, +/- subtraction. DCE was read on the dynamics or DynaCAD (Invivo, Gainesville, FL, USA). Fellowship-trained breast radiologists blindly double-read by consensus; additional reader/s arbitrated. The reference standard was the histopathology result or cancer registry notification for cancer diagnoses and benign biopsies, benign follow-up imaging or subsequent screening MRI.

RESULTS

Of 993 MRI studies in 554 women, 870 eligible MRI were performed in 471 women, and 706 had a reference standard. Median age was 44 years (range 18-80). The majority of studies (65% 457/706) were screening Medicare rebate-eligible high familial risk; 26% for surveillance after a breast cancer or contralateral staging; 6% screened BRCA carriers. Eleven cancers were diagnosed, eight were MRI-detected. Only two of these were at high-risk screening MRI. Five were detected at staging contralateral ILC, after negative 2D mammography and ultrasound. Cancer prevalence was highest for staging contralateral ILC, at 600/10,000 MRI, for high-risk screening 77/10,000 MRI and surveillance 116/10,000 MRI.

CONCLUSIONS

Cancers were predominantly detected in women undergoing preoperative staging of new invasive lobular carcinoma in the contralateral breast, rather than the Medicare rebate-eligible high-risk screening group.

Comparison of Breast MR Imaging with Molecular Breast Imaging in Breast Cancer Screening, Diagnosis, Staging, and Treatment Response Evaluation

Breast MR imaging and molecular breast imaging (MBI) are functional imaging modalities that can be used to noninvasively evaluate the pathophysiology and biology of breast cancer. In the era of personalized medicine, these imaging techniques give clinicians insight into cancer pathobiology and allows them to individualize treatment regimens. Breast MR imaging has gained acceptance for breast cancer evaluation; work is ongoing on validation of MBI for breast cancer evaluation. This article discusses clinical applications of breast MR imaging and MBI, and compares the performance of these techniques in breast cancer screening, diagnosis, staging, and treatment response evaluation.

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.

MRI for the Staging and Evaluation of Response to Therapy in Breast Cancer

Breast magnetic resonance imaging (MRI) is the most sensitive of the available imaging modalities to characterize breast cancer. Breast MRI has gained clinical acceptance for screening high-risk patients, but its role in the preoperative imaging of breast cancer patients remains controversial. This review focuses on the current indications for staging breast MRI, the evidence for and against the role of breast MRI in the preoperative staging workup, and the evaluation of treatment response of breast cancer patients.

ACR Appropriateness Criteria® Monitoring Response to Neoadjuvant Systemic Therapy for Breast Cancer

Patients with locally advanced invasive breast cancers are often treated with neoadjuvant chemotherapy prior to definitive surgical intervention. The primary aims of this approach are to: 1) reduce tumor burden thereby permitting breast conservation rather than mastectomy; 2) promptly treat possible metastatic disease, whether or not it is detectable on preoperative staging; and 3) potentially tailor future chemotherapeutic decisions by monitoring in-vivo tumor response. Accurate radiological assessment permits optimal management and planning in this population. However, assessment of tumor size and response to treatment can vary depending on the modality used, the measurement technique (such as single longest diameter, 3-D measurements, or calculated tumor volume), and varied response of different tumor subtypes to neoadjuvant chemotherapy (such as concentric shrinkage or tumor fragmentation). As discussed in further detail, digital mammography, digital breast tomosynthesis, US and MRI represent the key modalities with potential to help guide patient management. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Correlation between E-cadherin and p120 expression in invasive ductal breast cancer with a lobular component and MRI findings

Invasive breast cancer comprises a spectrum of histological changes with purely lobular cancer on one side and purely ductal cancer on the other, with many mixed lesions in between. In a previous study, we showed that in patients with any percentage lobular component at core needle biopsy, preoperative MRI leads to the detection of clinically relevant additional findings in a substantial percentage of patients, irrespective of the percentage of the lobular component. Detection of a small lobular component may however not be reproducible among pathologists. Loss of membrane expression of E-cadherin or p120 is useful biomarkers of ILC and may therefore support a more objective diagnosis. All patients diagnosed with breast cancer containing a lobular component of any percentage between January 2008 and October 2012 were prospectively offered preoperative MRI. Clinically relevant additional findings on MRI were verified by pathology evaluation. Expression patterns of E-cadherin and p120 were evaluated by immunohistochemistry on the core needle biopsy. MRI was performed in 109 patients. The percentage of lobular component was significantly increased in cases with aberrant E-cadherin or p120 expression (both p = <0.001). However, aberrant expression of E-cadherin and p120 was not related to the probability of detecting relevant additional MRI findings. E-cadherin and p120 did not appear to be useful objective biomarkers for predicting additional relevant findings on MRI in patients with a lobular component in the core needle of their breast cancer.

How I report breast magnetic resonance imaging studies for breast cancer staging and screening

Magnetic resonance imaging (MRI) of the breast is the most sensitive imaging technique for the diagnosis and local staging of primary breast cancer and yet, despite the fact that it has been in use for 20 years, there is little evidence that its widespread uncritical adoption has had a positive impact on patient-related outcomes.

This has been attributed previously to the low specificity that might be expected with such a sensitive modality, but with modern techniques and protocols, the specificity and positive predictive value for malignancy can exceed that of breast ultrasound and mammography. A more likely explanation is that historically, clinicians have acted on MRI findings and altered surgical plans without prior histological confirmation. Furthermore, modern adjuvant therapy for breast cancer has improved so much that it has become a very tall order to show a an improvement in outcomes such as local recurrence rates.

In order to obtain clinically useful information, it is necessary to understand the strengths and weaknesses of the technique and the physiological processes reflected in breast MRI. An appropriate indication for the scan, proper patient preparation and good scan technique, with rigorous quality assurance, are all essential prerequisites for a diagnostically relevant study.

The use of recognised descriptors from a standardised lexicon is helpful, since assessment can then dictate subsequent recommendations for management, as in the American College of Radiology BI-RADS (Breast Imaging Reporting and Data System) lexicon (Morris et al., ACR BI-RADS® Atlas, Breast Imaging Reporting and Data System, 2013). It also enables audit of the service. However, perhaps the most critical factor in the generation of a meaningful report is for the reporting radiologist to have a thorough understanding of the clinical question and of the findings that will influence management. This has never been more important than at present, when we are in the throes of a remarkable paradigm shift in the treatment of both early stage and locally advanced breast cancer.

Role of imaging in neoadjuvant therapy for breast cancer

Neoadjuvant chemotherapy (NAC) involves administration of chemotherapeutic agents to patients with newly diagnosed breast cancer prior to definitive surgical treatment. Assessment of disease response to chemotherapeutic agents in vivo prior to any surgical intervention is necessary as medical oncologists are commonly tailoring or changing therapy during NAC based on response. It can also maximize the pathologic complete response (pCR) rate, resulting in more women undergoing breast conservation rather than mastectomy. Although some studies show a pCR to NAC in only 13-26 % of women, recent studies have shown higher pCR rates, especially for HER2-positive disease treated with targeted anti-HER2 therapy. Thus, accurate imaging tools for quantifying disease response are critical in the evaluation and management of patients undergoing NAC. There is currently no standard imaging method for monitoring response to therapy. Response to therapy tends to vary by tumor subtype and can be accurately assessed on imaging. We review the role of imaging before and after neoadjuvant therapy and discuss the advantages and limitations of currently available modalities, including mammography, ultrasonography, magnetic resonance imaging, and nuclear imaging.

Evolving concepts in breast lobular neoplasia and invasive lobular carcinoma, and their impact on imaging methods

Invasive lobular carcinoma (ILC) and lobular neoplasia (LN) are two distinct conditions that still pose challenges regarding to their classification, diagnosis and management. Although they share similar cellular characteristics, such as discohesive neoplastic cells and absence of e-cadherin staining, they represent completely different conditions. LN encompasses atypical lobular hyperplasia (ALH) and lobular carcinoma in situ (LCIS), which are currently considered risk factors and non-obligatory precursors of breast neoplasia. These lesions are diagnosed as incidental findings in percutaneous biopsies or appear as non-specific clusters of punctate calcifications in mammograms. ILC is the second most common breast malignancy and has typical histological features, such as infiltrative growth and low desmoplasia. These histological features are reflected in imaging findings and constitute the reasons for typical subtle mammographic features of ILC, as architectural distortion or focal asymmetries. Ultrasonography (US) may detect almost 75 % of the ILCs missed by mammography and represents the modality of choice for guiding biopsies. Magnetic resonance imaging (MRI) exhibits a high sensitivity for the diagnosis of ILC and for detecting synchronous lesions.

Teaching Points

• LN includes ALH and LCIS, risk factors and non-obligatory precursors of breast cancer.

• Absence of e-cadherin staining is crucial for differentiation among ductal and lobular lesions.

• ILC has typical histological features, such as infiltrative growth and low desmoplasia.

• Mammographic features of ILC are often subtle and reflect the histological features.

• MRI exhibits a high sensitivity for the diagnosis of ILC and for detecting synchronous lesions.

The biology of malignant breast tumors has an impact on the presentation in ultrasound: an analysis of 315 cases

Background

The aim of this study was to evaluate the relation of some ultrasound morphological parameters to biological characteristics in breast carcinoma.

Methods

Ultrasound data from 315 breast masses were collected. We analyzed the ultrasound features of the tumors according to the ACR BI-RADS®-US classification system stratified by hormone receptor status, HER2 status, histology grade, tumor type (ductal versus lobular), triple-negativity, breast density, tumor size, lymph node involvement and patient’s age.

Results

We found a variety of ultrasound features that varied between the groups. Invasive lobular tumors were more likely to have an angulated margin (39% versus 22%, p = 0.040) and less likely to show posterior acoustic enhancement (3% versus 16%, p = 0.023) compared to invasive ductal carcinoma. G3 tumors were linked to a higher chance of posterior acoustic enhancement and less shadowing and the margin of G3 tumors was more often described as lobulated or microlobulated compared to G1/G2 tumors (67% versus 46%, p = 0.001). Tumors with an over-expression of HER2 exhibited a higher rate of architectural distortions in the surrounding tissue, but there were no differences regarding the other features. Hormone receptor negative tumors were more likely to exhibit a lobulated or microlobulated margin (67% versus 50%, p = 0.037) and less likely to have an echogenic halo (39% versus 64%, p = 0.001). Furthermore, the posterior acoustic feature was more often described as enhancement (33% versus 13%, p = 0.001) and less often as shadowing (20% versus 47%, p < 0.001) compared to hormone receptor positive tumors.

Conclusion

Depending on their biological and clinical profile, breast cancers are more or less likely to exhibit the typical criteria for malignancy in ultrasound. Moreover, certain types of breast cancer tend to possess criteria that are usually associated with benign masses. False-negative diagnosis may result in serious consequences for the patient. For the sonographer it is essential to be well aware of potential variations in the ultrasound morphology of breast tumors, as described in this paper.

Breast cancer size estimation with MRI in BRCA mutation carriers and other high risk patients

OBJECTIVE

To assess the value of breast MRI in size assessment of breast cancers in high risk patients, including those with a BRCA 1 or 2 mutation. Guidelines recommend invariably breast MRI screening for these patients and therapy is thus based on these findings. However, the accuracy of breast MRI for staging purposes is only tested in sporadic cancers.

METHODS

We assessed concordance of radiologic staging using MRI with histopathology in 49 tumors in 46 high risk patients (23 BRCA1, 12 BRCA2 and 11 Non-BRCA patients). The size of the total tumor area (TTA) was compared to pathology. In invasive carcinomas (n=45) the size of the largest focus (LF) was also addressed.

RESULTS

Correlation of MRI measurements with pathology was 0.862 for TTA and 0.793 for LF. TTA was underestimated in 8(16%), overestimated in 5(10%), and correctly measured in 36(73%) cases. LF was underestimated in 4(9%), overestimated in 5(11%), and correctly measured in 36(80%) cases. Impact of BRCA 1 or 2 mutations on the quality of size estimation was not observed.

CONCLUSIONS

Tumor size estimation using breast MRI in high risk patients is comparable to its performance in sporadic cancers. Therefore, breast MRI can safely be used for treatment planning.

Magnetic Resonance Imaging-Guided Breast Biopsy in Lesions Not Visualized by Mammogram or Ultrasound

The use of magnetic resonance imaging (MRI) for the diagnosis and evaluation of breast lesions is still in evolution. The aim of this study was to evaluate the outcome of MR-guided biopsy for suspicious lesions seen on MRI but not visualized by mammography or ultrasound. A retrospective review was conducted on all patients undergoing MRI-guided core needle biopsy at a National Cancer Institute-designated comprehensive cancer center. Biopsies were performed using a 1.5-Tesla MR with a seven-channel breast coil taking six cores in a clock face configuration with a 10-gauge vacuum-assisted VACORA biopsy device. One hundred twenty-seven patients underwent 187 biopsies without major complication. The lesion size ranged from 4 to 12 mm. Pathology on MRI-guided core biopsy material revealed 126 (68%) benign lesions. Of these, 12 were intraductal papillomas and two were fibroadenomas. Sixty-one (32%) were deemed clinically significant and included the following pathology: invasive cancer 19 patients (10%), ductal carcinoma in situ (DCIS) in 25 patients (13%), atypical ductal hyperplasia (ADH) 15 patients (8%), and lobular carcinoma in situ in one patient (1%). There were two specimens upgraded from ADH to DCIS and one specimen that was biopsied was called ADH but there was no residual atypia on final pathology. With a median follow-up of 24 months, there were no patients with benign pathology returning with a clinically significant lesion later. MRI-guided biopsy provides an accurate and safe method for sampling suspicious lesions when no other reasonable means of biopsy is available. MRI-guided biopsy yielded clinically significant findings in approximately one-third of the sampled specimens. This technique can provide a good representative sample of clinically significant pathology. MRI-guided biopsy is a relatively new modality, which can provide a nonsurgical diagnostic specimen in the absence of mammographic or ultrasound findings.

Invasive breast cancer: relationship between shear-wave elastographic findings and histologic prognostic factors

PURPOSE

To compare the histologic prognostic feature of invasive breast cancer with mean stiffness as measured with shear-wave elastography.

MATERIALS AND METHODS

This retrospective study was exempted from ethical committee review. Patient consent for use of images for research was obtained. The study group comprised 101 consecutive women (age range, 38-91 years) with solid lesions identified during routine breast ultrasonography (US) performed between April 2010 and March 2011 and subsequently confirmed at histologic examination to be invasive cancers. Four elastographic images in two orthogonal planes were obtained of each lesion, and mean stiffness values were obtained from each image. Histologic findings following surgery were used for comparison, namely histologic grade, tumor type, invasive size, vascular invasion status, and lymph node status. Relationship between mean stiffness and histologic parameters was investigated by using a general linear model and multiple regression analysis.

RESULTS

High histologic grade (P < .0001), large invasive size (P < .0001), lymph node involvement (P < .0001), tumor type (P < .0001), and vascular invasion (P = .0077) all showed statistically significant positive association with high mean stiffness values. Multiple linear regression indicated that invasive size is the strongest pathologic determinant of mean stiffness (P < .0001), with histologic grade also having significant influence (P = .022).

CONCLUSION

In this study, breast cancers with higher mean stiffness values at shear-wave elastography had poorer prognostic features.

The role of magnetic resonance imaging in early breast cancer

Despite recent evidence that fails to detect a benefit in surgical and local recurrence outcomes in those who receive optimal surgery and adjuvant systemic and radiotherapy, magnetic resonance imaging (MRI) is still being employed. We review the recent literature to clarify the role in the use of MRI in early breast cancer. A literature search using the Medline and Ovid databases was conducted between 2004 and 2011 using the terms "magnetic resonance imaging' and 'early breast cancer'. Only articles with clinical trials published in English in adult humans with available abstracts were included. Articles on high-risk women, response to neoadjuvant therapy, advanced breast cancer, the occult primary, the contralateral breast and technical articles were excluded. Articles examining the role of MRI in the staging of early breast cancer were retained. Over 260 articles regarding breast MRI have been published in the last 5 years. Additional foci may be found in 16% of patients but the impact on the extent of surgery and local recurrence rate is yet to be defined. Certain sub-groups who may benefit include those with invasive lobular carcinoma and mammographically dense breasts and those for consideration of partial breast irradiation. With standard adjuvant radiotherapy, there is no benefit in routine MRI with respect surgical extent and local recurrence. Should MRI be used, pre-operative biopsy to confirm additional disease must be undertaken prior to a change in surgical extent of resection. However, MRI may be useful in the evaluation of those who can be considered for partial breast irradiation. Centres undertaking breast MRI must have MRI-biopsy capabilities and constantly audit the reporting of MRI with correlation to the final pathology.

Does Preoperative Magnetic Resonance Imaging Beneficially Alter Surgical Management of Invasive Lobular Carcinoma?

The role of breast magnetic resonance imaging (MRI) in patients with newly diagnosed breast cancer remains controversial. The objective of this study is to determine the impact of preoperative breast MRI on patients with biopsy-proven invasive lobular carcinoma (ILC) initially deemed eligible for breast conserving therapy. We analyzed a prospective cohort study of patients with biopsy-proven ILC that consented to undergo preoperative diagnostic MRI at our institution. Data analysis of 20 patients accrued from January 2010 through January 2011 was performed. Outcome measures included discovery of occult lesions, need for additional biopsies, change in surgical management, and need for surgical reexcision. MRI found an additional cancer in 40 per cent of patients and increased extent of disease in one patient. MRI led to eight biopsies, for a pathologically confirmed true positive rate of 82 per cent [95% confidence interval (CI) 62-101%] and only two unnecessary biopsies. Preoperative MRI beneficially altered surgical management in 42 per cent of patients (95% CI 19-65%) without leading to unnecessary surgery, and only one patient required reexcision for positive margins (5.8%, CI -5.8-17.4%). In conclusion, preoperative MRI in patients with ILC can detect additional disease that was missed by conventional workup, allowing for better preoperative planning and more appropriate oncologic resection.