Case 285: Primary Breast Lymphoma.

History A 25-year-old woman was referred to our breast clinic for assessment of a palpable mass in her left breast that developed quickly in 2 weeks. She denied any associated fever, chills, redness, or pain. She had no relevant medical or surgical history; no evidence of recent pregnancy, abortion, or breastfeeding; and no family history of breast cancer. Clinical examination enabled confirmation of a firm mass occupying the retroareolar region and the outer quadrant of the left breast with no skin retraction, edema, or erythema. There was no evidence of enlarged axillary lymph nodes. US of the left breast, bilateral breast MRI, and fluorine 18 (18F) fluorodeoxyglucose (FDG) PET/CT were performed.

Case 285.

History A 25-year-old woman was referred to our breast clinic for assessment of a palpable mass in her left breast that developed quickly in 2 weeks. She denied any associated fever, chills, redness, or pain. She had no relevant medical or surgical history; no evidence of recent pregnancy, abortion, or breastfeeding; and no family history of breast cancer. Clinical examination enabled confirmation of a firm mass occupying the retroareolar region and the outer quadrant of the left breast with no skin retraction, edema, or erythema. There was no evidence of enlarged axillary lymph nodes. US of the left breast (Fig 1), bilateral breast MRI (Fig 2), and fluorine 18 fluorodeoxyglucose PET/CT (Fig 3) were performed.

Added Value of Quantitative Ultrasound and Machine Learning in BI-RADS 4-5 Assessment of Solid Breast Lesions.

The purpose of this study was to evaluate various combinations of 13 features based on shear wave elasticity (SWE), statistical and spectral backscatter properties of tissues, along with the Breast Imaging Reporting and Data System (BI-RADS), for classification of solid breast lesions at ultrasonography by means of random forests. One hundred and three women with 103 suspicious solid breast lesions (BI-RADS categories 4-5) were enrolled. Before biopsy, additional SWE images and a cine sequence of ultrasound images were obtained. The contours of lesions were delineated, and parametric maps of the homodyned-K distribution were computed on three regions: intra-tumoral, supra-tumoral and infra-tumoral zones. Maximum elasticity and total attenuation coefficient were also extracted. Random forests yielded receiver operating characteristic (ROC) curves for various combinations of features. Adding BI-RADS category improved the classification performance of other features. The best result was an area under the ROC curve of 0.97, with 75.9% specificity at 98% sensitivity.

Comparative Evaluation of Iodine-125 Radioactive Seed Localization and Wire Localization for Resection of Breast Lesions.

PURPOSE: Radioactive seed localization (RSL) uses a titanium seed labeled with iodine-125 energy for surgery of nonpalpable breast lesions. RSL facilitates radiology-surgery scheduling and allows for improved oncoplasty compared with wire localization (WL). The purpose of this work was to compare the 2 techniques. METHODS: We performed a retrospective study of all breast lesions operated with RSL between February 2013 and March 2015 at our university institution, and compared with an equivalent number of surgeries performed with a single WL. Imaging and pathology reports were reviewed for information on guidance mode, accuracy of targeting, nature of excised lesion, size and volume of surgical specimen, status of margins, and reinterventions. RESULTS: A total of 254 lesions (247 women) were excised with RSL and compared with 257 lesions (244 women) whose surgery was guided by WL. Both groups were comparable in lesion pathology, guidance mode for RSL or WL positioning, and accuracy of targeting (98% correct). Mean delay between biopsy and surgery was 84 days for RSL versus 103 after WL (P = .04). No differences were noted after RSL or WL for surgical specimen mean weight, largest diameter, and volume excised. For malignancies, the rate of positive margins was comparable (2.8%-3%), with 5 of 10 women in the RSL group who underwent a second surgery displaying residual malignancy compared with 3 of 9 women in the WL group. CONCLUSIONS: RSL is safe and accurate, and has comparable surgical endpoints to WL. Because RSL offers flexible scheduling and facilitated oncoplasty, RSL may replace WL for resection of nonpalpable single breast lesions.

Lupus mastitis as a first manifestation of systemic disease: About two cases with a review of the literature.

Lupus mastitis is an uncommon manifestation of systemic lupus erythematosus (SLE) that affects the subcutaneous fat in the breast, much like lupus panniculitis, but additionally involves the mammary gland. We report on two women for whom lupus mastitis was the initial manifestation of SLE and provide a literature review of 34 additional cases reported in the Anglo-Saxon and French literature since 1971, making this the largest review to date. Lupus mastitis (LM) can manifest clinically as subcutaneous masses that may be painful, or may present cutaneous involvement such as thickening and discolouration. The radiologic manifestations of LM are broad and include calcifications, masses and asymmetries. Most often, excluding malignancy requires percutaneous biopsy, with histologic findings that are virtually pathognomonic for SLE. Thus, surgery is avoided and medical management can begin, antimalarial drugs and corticosteroids in most cases.

Is the outcome at surgery different when flat epithelial atypia and lobular neoplasia are found in association at biopsy?

OBJECTIVE: To assess the impact on the final outcome at surgery of flat epithelial atypia (FEA) when found concomitantly with lobular neoplasia (LN) in biopsy specimens compared with pure biopsy-proven FEA. METHODS: The approval from the institutional review board of the CHUM (Centre Hospitalier Universitaire de Montréal) was obtained. A retrospective review of our database between 2009 and 2013 identified 81 females (mean age 54 years, range 38-90 years) with 81 FEA biopsy-proven lesions. These were pure or associated with LN only in 59/81 (73%) and 22/81 (27%) cases, respectively. Overall, 57/81 (70%) patients underwent surgery and 24/81 (30%) patients underwent mammographic surveillance with a mean follow-up of 36 months. RESULTS: FEA presented more often as microcalcifications in 68/81 (84%) patients and were mostly amorphous in 49/68 (72%). After excluding radio pathologically discordant cases, pure FEA proved to be malignant at surgery in 1/41 (2%; 95% confidence interval 0.06-12.9). There was no statistically significant difference in the upgrade to malignancy whether FEA lesions were pure or associated to LN at biopsy (p = 0.4245); however, when paired in biopsy specimens, these lesions were more frequently associated with atypical ductal hyperplasia (ADH) at surgery than with pure FEA (p = 0.012). CONCLUSION: Our results show a 2% upgrade rate to malignancy of pure FEA lesions. When FEA is found in association with LN at biopsy, surgical excision yields more frequently ADH than pure FEA thus warranting close surveillance or even surgical excision. Advances in knowledge: The association of LN with FEA at biopsy was more frequently associated with ADH at surgery than with pure FEA. If a biopsy-proven FEA lesion is deemed concordant with the imaging finding, when paired with LN at biopsy, careful surveillance or even surgical excision is suggested.

Breast Biopsies Under Magnetic Resonance Imaging Guidance: Challenges of an Essential but Imperfect Technique.

Magnetic resonance imaging (MRI)-guided breast biopsy is an essential tool of a breast imager; yet, a decade after its introduction, this technique remains challenging and imperfect. This article presents the technique of MRI-guided biopsy, with an emphasis on challenges particular to the technique: technical considerations related to adequate lesion sampling and difficulties in confirming radiologic-pathologic correlation for enhancing lesions. Through clinical vignettes, challenges unique to MRI-guided biopsy are discussed and practical tips are offered. Prebiopsy planning including second-look targeted studies, patient preparation, and equipment is covered. Challenging situations pertaining to breast size, lesion location, or type of enhancement are illustrated, as well as the topic of performing multiple MRI-guided breast biopsies in a single session and biopsies of women with implants. Postbiopsy management is discussed. Success of MRI-guided biopsies requires careful prebiopsy planning, as well as appropriate choice of biopsy device, optimized for the specifics of breast shape and lesion size and location. Special features of biopsy systems (smaller apertures and blunt tips) facilitate the sampling of lesions in challenging locations. Vanishing lesions should undergo short-term follow-up, because malignancy cannot be excluded, as should lesions diagnosed as benign after pathologic analysis when the result is felt to be concordant with imaging features. To this end, radiologic-pathologic correlation is essential. Underestimation rates after MRI-guided breast biopsy are superior to those for vacuum-assisted stereotactic biopsy and ultrasound-guided biopsy. Close follow-up and rebiopsy should be considered when there is imaging-discordant histology. For benign and concordant histology, a first follow-up can be offered at 6 months.

Breast imaging reporting and data system (BI-RADS) lexicon for breast MRI: interobserver variability in the description and assignment of BI-RADS category.

PURPOSE: To retrospectively evaluate interobserver variability between breast radiologists when describing abnormal enhancement on breast MR examinations and assigning a BI-RADS category using the Breast Imaging Reporting and Data System (BI-RADS) terminology. MATERIALS AND METHODS: Five breast radiologists blinded to patients' medical history and pathologic results retrospectively and independently reviewed 257 abnormal areas of enhancement on breast MRI performed in 173 women. Each radiologist described the focal enhancement using BI-RADS terminology and assigned a final BI-RADS category. Krippendorff's α coefficient of agreement was used to asses interobserver variability. RESULTS: All radiologists agreed on the morphology of enhancement in 183/257 (71%) lesions, yielding a substantial agreement (Krippendorff's α=0.71). Moderate agreement was obtained for mass descriptors - shape, margins and internal enhancement - (α=0.55, 0.51 and 0.45 respectively) and NME (non-mass enhancement) descriptors - distribution and internal enhancement - (α=0.54 and 0.43). Overall substantial agreement was obtained for BI-RADS category assignment (α=0.71). It was however only moderate (α=0.38) for NME compared to mass (α=0.80). CONCLUSION: Our study shows good agreement in describing mass and NME on a breast MR examination but a better agreement in predicting malignancy for mass than NME.

Molecular classification of infiltrating breast cancer: toward personalized therapy.

Breast cancer is a heterogeneous disease, which comprises several molecular and genetic subtypes, each with characteristic clinicobiologic behavior and imaging patterns. Traditional classification of breast cancer is based on the histopathologic features but offers limited prognostic value. Novel molecular characterization of breast cancer with cellular markers has allowed a new classification that offers prognostic value, with predictive categories of disease aggressiveness. These molecular signatures also open the door to personalized therapeutic options, with new receptor-targeted therapies. For example, invasive cancer subtypes such as the luminal A and B subtypes show better prognosis and response to hormone receptor-targeted therapies compared with the triple-negative subtypes; on the other hand, triple-negative tumors respond better than luminal tumors to chemotherapy. Tumors that display amplification of the oncogene ERBB2 (also known as the HER2/neu oncogene) respond to drugs directed against this oncogene, such as trastuzumab. The imaging aspects of tumors correlate with molecular subgroups, as well as other pathologic features such as nuclear grade. Smooth tumor margins at mammography may be suggestive of a triple-negative breast cancer, and a human epidermal growth factor receptor 2 (HER2)-positive tumor is characteristically a spiculated mass with calcifications. Low-grade ductal carcinoma in situ (DCIS) is better detected with mammography, although magnetic resonance (MR) imaging may allow better characterization of high-grade DCIS. MR imaging diffusion sequences show higher values for the apparent diffusion coefficient for triple-negative and HER2-positive subtypes, compared with luminal A and B tumors. MR imaging is also a useful tool in the prediction of tumor response after chemotherapy, especially for triple-negative and HER2-positive subtypes.

Case 201: glomus tumor of the breast.

History A 55-year-old woman presented to our breast clinic with 1-year history of lancinating pain in the right breast that was exacerbated by blunt pressure and cold temperature. She denied any family history of breast cancer or any personal history of trauma, infection, or surgery of the breast. On clinical examination, exquisite pain was generated by simple light pressure over the upper outer quadrant of the right breast. Mammography and ultrasounography (US) with Doppler analysis of the right breast were painful but were performed with the least pressure possible.

Breast reconstruction: review of surgical methods and spectrum of imaging findings.

Breast reconstruction after mastectomy is often requested by women with breast cancer who are ineligible for breast-conserving therapy and women with a high genetic risk for breast cancer. Current breast reconstruction techniques are diverse and may involve the use of an autologous tissue flap, a prosthetic implant, or both. Regardless of the technique used, cancer may recur in the reconstructed breast; in addition, in breasts reconstructed with autologous tissue flaps, benign complications such as fat necrosis may occur. To detect breast cancer recurrences at a smaller size than can be appreciated clinically and as early as possible without evidence of metastasis, radiologists must be familiar with the range of normal and abnormal imaging appearances of reconstructed breasts, including features of benign complications as well as those of malignant change. Images representing this spectrum of findings were selected from the clinical records of 119 women who underwent breast magnetic resonance (MR) imaging at the authors' institution between January 2009 and March 2011, after mastectomy and breast reconstruction. In 32 of 37 women with abnormal findings on MR images, only benign changes were found at further diagnostic workup; in the other five, recurrent breast cancer was found at biopsy. Four of the five had been treated initially for invasive carcinoma, and one, for multifocal ductal carcinoma; three of the five were carriers of a BRCA gene mutation. On the basis of these results, the authors suggest that systematic follow-up examinations with breast MR imaging may benefit women with a reconstructed breast and a high risk for breast cancer recurrence.

Chronic granulomatous mastitis: Imaging, pathology and management.

PURPOSE: The aim of this study is to describe the clinical and radiological presentation of chronic granulomatous mastitis. MATERIAL AND METHODS: We retrospectively reviewed the clinical and radiological data of 11 women with histologically proven chronic granulomatous mastitis (CGM) diagnosed between March 2008 and September 2011. RESULTS: The diagnosis of CGM is often a challenging one that can mimic infectious and malignant breast conditions. Clinically, CGM most commonly presents as a mass, occasionally with associated erythema. The most frequent mammographic presentation is an asymmetric density, while ultrasound most commonly reveals a hypoechoic mass with tubular extensions and a striated echotexture. On MRI, the most specific finding is peripherally enhancing fluid or solid masses with fistulous tract to the skin, although the latter is not commonly encountered. Diagnosis can be reliably obtained by needle core or vacuum-assisted biopsy, and is established pathologically by the identification of granulomatous inflammation without caseous necrosis. CGM is a diagnosis of exclusion after infectious and foreign body causes are ruled out. Treatment options include oral steroids or surgery; both options are associated with similar recurrence rates. The disease tends to burn itself out and the option of conservative management with observation is a valid one. CONCLUSION: CGM is a rare benign disease with no specific features clinically or at imaging. There are no radiologic findings that are specific of CGM, but in the appropriate clinical setting, the diagnosis can be suggested by the radiologist.

Surgical outcome of biopsy-proven lobular neoplasia: is there any difference between lobular carcinoma in situ and atypical lobular hyperplasia?

OBJECTIVE: The aims of our study were to determine the frequency of malignancy after surgical excision of biopsy-proven lobular carcinoma in situ (LCIS) or atypical lobular hyperplasia (ALH) lesions, to assess any difference between pure LCIS and pure ALH lesions regarding their radiologic presentation and the malignancy upgrade rate after surgical excision, and to evaluate the outcome of lesions that were not excised surgically but were followed up. MATERIALS AND METHODS: Radiologic and pathologic records of 14,435 imaging-guided needle biopsies of the breast performed between 2004 and 2008 in three different institutions were retrospectively reviewed. A total of 126 patients (0.9%) had biopsy-proven LCIS or ALH, or both, as the highest-risk lesion. Among the 126 patients, 89 (71%) continued to surgery, and 14 were followed up for more than 24 months. The Mantel-Haensel chi-square test was used for statistical analysis. RESULTS: Cancer upgrade was documented in 17 of the 43 LCIS (40%), 11 of the 40 ALH (27%), and two of the six combined ALH and LCIS lesions (33%) surgically excised, for a total malignancy upgrade rate of 34% (30/89). Both LCIS and ALH lesions presented mammographically in most cases as microcalcifications (p = 0.078). None of the 14 patients followed up for a mean period of 51 months showed development of malignancy. CONCLUSION: No statistically significant difference was found between mammographic presentation and postsurgical outcome of LCIS versus ALH lesions. Surgical excision of these lesions is recommended as long as no evident criteria are provided to differentiate those that might be associated with an underlying malignancy.

A plea for the biopsy marker: how, why and why not clipping after breast biopsy?

In the last decade, percutaneous breast biopsies have become a standard for the management of breast diseases. Biopsy clips allow for precise lesion localization, thus minimizing the volume of breast to be resected at the time of surgery. With the development of many imaging techniques (including mammography, sonography, and breast magnetic resonance imaging), one of the challenges of the multidisciplinary became to synthesize all informations obtained from the various imaging procedures. The use of biopsy markers after percutaneous biopsy is one of the keys for optimal patient management, helping the radiologist to deal with multiple lesions, to insure correlation across different imaging modalities and to follow-up benign lesions, helping the oncologist by marking a tumor prior to neoadjuvant chemotherapy, helping the surgeon by facilitating preoperative needle localization, to precisely mark the margins of extensive disease and to guide intraoperative tumor resection, and helping the pathologist to insure the lesion of interest has been removed and to identify the region of interest in a mastectomy specimen. We believe biopsy clip markers should be deployed after all percutaneous interventions and present in this review the arguments to support this statement. Minimal indications for clip deployment will also be detailed.

Breast abscesses: evidence-based algorithms for diagnosis, management, and follow-up.

Radiologists who regularly perform breast ultrasonography will likely encounter patients with breast abscesses. Although the traditional approach of surgical incision and drainage is no longer the recommended treatment, there are no clear guidelines for management of this clinical condition. Breast abscesses that develop in the puerperal period generally have a better course than nonpuerperal abscesses, which tend to be associated with longer treatment times and a higher rate of recurrence. The available literature on treatment of breast abscesses is imperfect, with no clear consensus on drainage, antibiotic therapy, and follow-up. By synthesizing the data available from studies published in the past 20 years, an evidence-based algorithm for management of breast abscesses has been developed. The proposed algorithm is easy to follow and has been validated by a multidisciplinary team approach and applied successfully during the past 2 years. Breast abscesses are a challenging clinical condition, and radiologists have a pivotal role in evaluation and follow-up of these lesions.

Nonmasslike enhancement at breast MR imaging: the added value of mammography and US for lesion categorization.

PURPOSE: To determine the value of adding conventional imaging (mammography and ultrasonography [US]) to nonmasslike enhancement (NMLE) analysis with breast magnetic resonance (MR) imaging for predicting malignancy and for building an interpretation model incorporating all imaging modalities. MATERIALS AND METHODS: The institutional ethics committees approved the study and granted a waiver of informed consent. In 115 women (mean age, 48.3 years; range, 21-76 years; 56 malignant, 12 high-risk, and 63 benign lesions), 131 NMLE lesions were analyzed. Two independent readers first classified MR images by using descriptive Breast Imaging Reporting and Data System (BI-RADS) criteria (BI-RADS classification with MR images alone [BI-RADS(MR)]) and later repeated this classification, adding information from conventional imaging (BI-RADS classification with combination of MR images and conventional images [BI-RADS(MR+Con)]). Lesion diagnosis was established with surgical histopathologic findings (n = 68), percutaneous biopsy results (n = 25), or 2 years of stability at MR imaging (n = 38). Receiver operating characteristic curves were built to compare BI-RADS(MR) with BI-RADS(MR+Con). A multivariate interpretation model was constructed and validated in a distinct cohort of 44 women. RESULTS: Values for inter- and intraobserver agreement, respectively, were better for BI-RADS(MR+Con) (κ = 0.847 and 0.937) than for BI-RADS(MR) (κ = 0.748 and 0.861). For both readers, the areas under the receiver operating characteristic curve (AUCs) for diagnosis of malignancy were also superior when BI-RADS(MR+Con) (AUC = 0.91 [reader 1] and 0.93 [reader 2]) was compared with BI-RADS(MR) (AUC = 0.84 [reader 1] and 0.87 [reader 2]) (P < .05). An interpretation model combining conventional imaging with MR imaging criteria showed very good discrimination (AUC = 0.89 [training set] and 0.90 [validating set]). CONCLUSION: Adding conventional imaging to NMLE lesion characterization at breast MR imaging improved the diagnostic performance of radiologists, and the interpretation model used offers good accuracy with the potential to optimize the reproducibility of NMLE analysis at MR imaging.

Microcalcifications around a collagen-based breast biopsy marker: complication of biopsy with a percutaneous marking system.

OBJECTIVE: The purpose of this article is to present the cases of four women who underwent percutaneous breast biopsy with deployment of a titanium metallic marker embedded in a bioresorbable collagen plug. Routine follow-up mammography after benign pathologic results were obtained revealed new fine microcalcifications at the biopsy sites, requiring repeat biopsy. Pathologic examination confirmed the presence of microcalcifications associated with an acidophilic foreign material. CONCLUSION: Awareness that development of microcalcifications can complicate biopsy performed with collagen-based markers is important for correct mammographic interpretation and management.

Imaging findings of breast augmentation with injected hydrophilic polyacrylamide gel: patient reports and literature review.

Hydrophilic polyacrylamide gel (PAAG) is a nonresorbable soft tissue filler that has been used as implant material for breast augmentation in some countries, particularly from the Asian continent. Many complications associated with hydrogel use have been reported in the clinical literature including inflammation, persistent mastodynia, formation of multiple lumps, poor cosmetic results, glandular atrophy, and significant spread of hydrogel into the surrounding tissue. Data on long-term toxicity is currently unavailable. The radiologic features of PAAG injection mammoplasty frequently constitute a diagnostic challenge for radiologists. Indeed, the imaging appearances of uncomplicated PAAG implants may mimic conventional implants on mammography, sonography and MRI, with some distinguishing features. The location and local spread of the injected PAAG, and the eventual detection of local inflammation, are best evaluated by ultrasonography and especially MRI, considered the most sensitive technique for assessment of PAAG mammoplasty. MRI clearly depicts the volume and the distribution of gel within the breast; contrast medium enhancement allows delineation of areas of inflammation and infection. It is important to be familiar with the spectrum of imaging findings in order to make an accurate diagnosis and offer proper management. This paper aims to review the normal and abnormal mammographic, sonographic, and MR imaging characteristics of PAAG augmentation mammoplasty through presented patient reviews of three women having undergone direct PAAG injection.

Second-look targeted studies after breast magnetic resonance imaging: practical tips to improve lesion identification.

Second-look studies, so-called because a re-evaluation of the breast is performed after review of magnetic resonance imaging (MRI) findings, offer the possibility of identifying correlates to MRI-detected lesions that were not previously suspected at mammography or ultrasound, thereby permitting immediate biopsy. To maximize the identification of ultrasound and mammographic correlates to MRI-identified lesions, one must carefully review the initial MRI examination as well as be cognizant of breast normal anatomy and variations in breast position across imaging modalities. We review the steps required for planification and realization of a successful second-look evaluation. After a correlate has been found and percutaneous biopsy performed, we recommend obtaining a T1-weighted noncontrast MRI sequence to verify metallic marker placement at the site of biopsy. This step ensures correct correlation between imaging modalities, provides immediate feedback for the radiologist, and, in case of error, allows the patient to be immediately redirected to repeat biopsy, often under MRI guidance. In the case of correct correlation, short-term follow-up is recommended, as for other breast percutaneous interventional procedures. We propose a simple management algorithm following second-look targeted studies.