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

ACR Appropriateness Criteria® Imaging of Invasive Breast Cancer

As the proportion of women diagnosed with invasive breast cancer increases, the role of imaging for staging and surveillance purposes should be determined based on evidence-based guidelines. It is important to understand the indications for extent of disease evaluation and staging, as unnecessary imaging can delay care and even result in adverse outcomes. In asymptomatic patients that received treatment for curative intent, there is no role for imaging to screen for distant recurrence. Routine surveillance with an annual 2-D mammogram and/or tomosynthesis is recommended to detect an in-breast recurrence or a new primary breast cancer in women with a history of breast cancer, and MRI is increasingly used as an additional screening tool in this population, especially in women with dense breasts. 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.

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.

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.

Predictive factors of major deviation (>20 mm) between lesion sizes measured by magnetic resonance imaging and histology for invasive lobular breast cancer

OBJECTIVE

To identify factors predictive of high discordance (>20 mm) between lesion sizes measured by magnetic resonance imaging (MRI) and histology for invasive lobular breast cancer.

MATERIALS AND METHODS

Data for all women with invasive lobular breast cancer (pure or associated with a component of invasive ductal carcinoma) between 1st January 2007 and 31st December 2016 were included in this study. Logistic regression analysis was performed to determine factors predictive of high discordance (underestimation/overestimation by >20 mm) between tumour sizes measured by MRI and histology for invasive lobular breast cancer.

RESULTS

For overestimation, significant factors on univariate analysis were: menopausal status [odds ratio (OR) 0.27, 95 % confidence interval (CI) 0.10-0.71]; p = 0.01], hormone receptor (HR) status (HR negative, OR 1.64, 95 % CI 0.27-9.89; HR positive, OR 0.64, 95 % CI 0.21-1.88; p = 0.09) and neoadjuvant chemotherapy (OR 10.33, 95 % CI 3.58-29.8; p < 0.001). On multivariate analysis, menopausal status and neoadjuvant chemotherapy were found to be independent predictive factors of overestimation. For underestimation, significant factors on univariate analysis were: histological size (OR 1.05, 95 % CI 1.02-1.08; p < 0.0001) and the presence of an in-situ component (OR 4.66, 95 % CI 1.01-21.5; p = 0.02). These two factors were independent predictive factors of underestimation.

CONCLUSION

Independent predictive factors of overestimation/underestimation (threshold 20 mm) of tumour sizes measured by MRI compared with histology for invasive lobular breast cancer were identified.

Agreement between dynamic contrast-enhanced magnetic resonance imaging and pathologic tumour size of breast cancer and analysis of the correlation with BI-RADS descriptors

Purpose

The purpose of this study was to evaluate magnetic resonance imaging (MRI)-pathology concordance of tumour size in patients with invasive breast carcinoma, with an emphasis on Breast Imaging Reporting and Data System (BI-RADS) descriptors of dynamic contrast-enhanced MRI (DCE-MRI).

Material and methods

Of patients who had preoperative DCE-MRI, 94 were enrolled. Concordance between MRI and the pathological findings was defined as a difference in tumour size of 5 mm or less. The greatest dimension was measured by two radiologists, and BI-RADS descriptives were described in accordance. The gold standard was chosen as the pathologic assessment.

Results

Tumour measurements determined by MRI and the pathological reports were not statistically different (2.64 ± 1.16 cm, Wilcaxon Z = –1.853, p = 0.064). Tumour sizes were concordant in 72/94 patients (76.6%). The mean difference between the pathological and MRI tumour sizes was –0.1 cm. MRI overestimated the size of 17/94 tumours (18.1%) and underestimated the size of 5/94 tumours (5.3%). Discordance was associated with larger tumour size. Histologic and molecular type of tumours, patient age, histologic grade, lymphovascular invasion or perineural invasion positivity, fibroglandular volume, background parenchymal enhancement, and being mass or non-mass were not associated with concordance. Irregular margin and heterogenous enhancement in DCE-MRI were associated with discordance in logistic regression analysis (p = 0.035, OR: 4.24; p = 0.021, OR: 4.96).

Conclusions

Two BI-RADS descriptors of irregular contour and heterogeneous contrast uptake were found to be associated with tumour size discrepancy. This might be attributed to the dynamic and morphologic specialities of tumours primarily rather than tumour biology.

[Predictive factors of concordance (5mm threshold) between MRI and histological sizes of invasive lobular breast cancer]

OBJECTIVE

The aim of this study was to search for predictive factors of concordance between MRI and histological sizes for invasive lobular breast cancer.

MATERIAL AND METHODS

All women managed for an invasive lobular breast cancer (pure or associated to a component of invasive ductal carcinoma) between 1st january 2007 and 31th december 2016 were included to the study. Univariable and multivariable analysis were performed to determine clinical or histological predictive factors of concordance between MRI and histological sizes for invasive lobular breast cancer (threshold 5mm).

RESULTS

During the study period 384 women were managed in our center for an invasive lobular carcinoma. We had access to the breast MRI of 246 of them. For a concordance witha threshold of 5mm, significant factors in univariate analysis were: menopausal status (OR 1.93[1.01-3.71], P=0.04), histological size (OR 0.97 [0.96-0.99], P<0.0001), lthe size of associated in situ component (OR 0.74 [0.32-1.71], P=0.01), multifocality (OR 0.56 [0.33-0.95] P=0.03) and the histological isolated invasive lobular carcinoma versus mixed ((OR 2.64 [1.01-6.91], P=0.03). In multivariate analysis, menopausal status, histological size and the histological isolated invasive lobular carcinoma versus mixed, were considered as independent predictive factors.

CONCLUSION

This work identified independent predictive factors of concordance between MRI and histological sizes for invasive lobular breast cancer (threshold 5mm).

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.

Clinical accuracy of preoperative breast MRI for breast cancer

BACKGROUND

It is unclear if breast magnetic resonance imaging (MRI) is more accurate than mammography (MGM) and ultrasound (U/S) in aggregate for patients with invasive cancer.

METHODS

We compared concordance of combined tumor size and tumor foci between MRI and MGM and U/S combined to pathological tumor size and foci as the gold standard from 2009 to 2015. Tumor size was nonconcordant if it differed from the pathologic size by ≥33% and tumor foci was nonconcordant if >1 foci were seen. If one or both of the MGM or U/S was nonconcordant and the MRI was concordant, MRI provided greater accuracy.

RESULTS

Of 471 patients with MGM, US, and MRI, MRI was more accurate for 32.9% of patients for tumor size and for 21.9% for tumor foci. Patients for whom MRI had greater accuracy were compared to those who did not for clinical and tumor factors. The only significant factor was calcifications on mammography. Tumor size, stage, molecular subtype, histology, grade, patient BMI, age, mammographic density, and use of hormone replacement therapy were not significantly different.

CONCLUSIONS

Breast MRI provides greater accuracy for a third of patients undergoing preoperative MGM and U/S. Mammographic calcifications were associated with MRI clinical accuracy for patients with invasive cancer.

CDH1 germline mutations and hereditary lobular breast cancer

Hereditary diffuse gastric cancer is an autosomal dominant inherited disease associated of CDH1 germline mutations (that encodes for the E-cadherin protein), and lobular breast cancer is the second most frequent type of neoplasia. Recently, novel E-cadherin constitutional alterations have been identified in pedigree clustering only for lobular breast carcinoma without evidence of diffuse gastric tumors and in absence of BRCA1/2 mutations. This first evidence opens novel questions about the inherited correlation between diffuse gastric and lobular breast cancers. In this brief review we revise the literature data about the CDH1 mutation frequency affecting exclusively lobular breast cancer, providing clinical recommendation for asymptomatic mutation carriers.

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.

E-cadherin germline mutation carriers: clinical management and genetic implications

Hereditary diffuse gastric cancer is an autosomic dominant syndrome associated with E-cadherin protein (CDH1) gene germline mutations. Clinical criteria for genetic screening were revised in 2010 by the International Gastric Cancer Linkage Consortium at the Cambridge meeting. About 40 % of families fulfilling clinical criteria for this inherited disease present deleterious CDH1 germline mutations. Lobular breast cancer is a neoplastic condition associated with hereditary diffuse gastric cancer syndrome. E-cadherin constitutional mutations have been described in both settings, in gastric and breast cancers. The management of CDH1 asymptomatic mutation carriers requires a multidisciplinary approach; the only life-saving procedure is the prophylactic total gastrectomy after thorough genetic counselling. Several prophylactic gastrectomies have been performed to date; conversely, no prophylactic mastectomies have been described in CDH1 mutant carriers. However, the recent discovery of novel germline alterations in pedigree clustering only for lobular breast cancer opens up a new debate in the management of these individuals. In this critical review, we describe the clinical management of CDH1 germline mutant carriers providing specific recommendations for genetic counselling, clinical criteria, surveillance and/ or prophylactic surgery.

Magnetic resonance imaging in patients with newly diagnosed breast cancer: a review of the literature

The use of magnetic resonance imaging (MRI) in patients with newly diagnosed breast cancer remains controversial. Here we review the current use of breast MRI and the impact of MRI on short-term surgical outcomes and rates of local recurrence. In addition, we address the use of MRI in specific patient populations, such as those with ductal carcinoma in situ, invasive lobular carcinoma, and occult primary breast cancer, and discuss the potential role of MRI for assessing response to neoadjuvant chemotherapy. Although MRI has improved sensitivity compared with conventional imaging, this has not translated into improved short-term surgical outcomes or long-term patient benefit, such as improved local control or survival, in any patient population. MRI is an important diagnostic test in the evaluation of patients presenting with occult primary breast cancer and has shown promise in monitoring response to neoadjuvant chemotherapy; however, the data do not support the routine use of perioperative MRI in patients with newly diagnosed breast cancer. Cancer 2014;120:120:2080-2089. © 2014 American Cancer Society.