The postconservation breast: part 1, Expected imaging findings. AJR Am J Roentgenol. 2012;198:321-330. [PMID: 22268174 DOI: 10.2214/ajr.10.7298]

Fibrocystic Change

Fibrocystic changes are commonly seen in clinically symptomatic patients and during imaging workup of screening-detected findings. The term "fibrocystic changes" encompasses a broad spectrum of specific benign pathologic entities. Recognition of classically benign findings of fibrocystic changes, including cysts and layering calcifications, can prevent unnecessary follow-ups and biopsies. Imaging findings such as solid masses, nonlayering calcifications, and architectural distortion may require core needle biopsy for diagnosis. In these cases, understanding the varied appearances of fibrocystic change aids determination of radiologic-pathologic concordance. Management of fibrocystic change is typically conservative.

The Postoperative Breast: Imaging Findings and Diagnostic Pitfalls After Breast-Conserving Surgery and Oncoplastic Breast Surgery

Breast surgery is the cornerstone of treatment for early breast cancer. Historically, mastectomy and conventional breast-conserving surgery (BCS) were the main surgical techniques for treatment. Now, oncoplastic breast surgery (OBS), introduced in the 1990s, allows for a combination of BCS and reconstructive surgery to excise the cancer while preserving or enhancing the contour of the breast, leading to improved aesthetic results. Although imaging after conventional lumpectomy demonstrates typical postsurgical changes with known evolution patterns over time, OBS procedures show postsurgical changes/fat necrosis in locations other than the lumpectomy site. The purpose of this article is to familiarize radiologists with various types of surgical techniques for removal of breast cancer and to distinguish benign postoperative imaging findings from suspicious findings that warrant further work-up.

Performance Metrics of Screening Digital Breast Tomosynthesis Based on Years Since a Prior Breast Cancer Diagnosis

BACKGROUND. Mammography surveillance protocols after breast cancer treatment vary widely. Some practices recommend performing diagnostic mammography for a certain number of years or indefinitely, whereas others recommend returning immediately to screening. OBJECTIVE. This study's objective was to determine performance metrics of screening digital breast tomosynthesis (DBT) in patients who resume screening mammography immediately after breast cancer treatment, based on the number of years since the breast cancer diagnosis. METHODS. This retrospective study included screening DBT examinations performed from January 2013 to June 2019 in patients who resumed screening mammography immediately after a prior breast cancer diagnosis. Multivariable logistic regression models with generalized estimating equations were used to evaluate associations between screening performance metrics and years since the prior breast cancer diagnosis, controlling for age, race and ethnicity, breast density, presence of a prior screening mammogram, and interpreting radiologist. RESULTS. The study included 8090 patients (mean age, 65 ± 11 [SD] years) with a prior breast cancer diagnosis who underwent 30,812 screening DBT examinations during the study period. The cancer detection rate (CDR) was 8.6 per 1000 examinations (265/30,812), abnormal interpretation rate (AIR) was 5.7% (1750/30,812), PPV1 was 15.1% (265/1750), sensitivity was 80.3% (265/330), specificity was 95.1% (28,997/30,482), and false-negative rate was 2.1 per 1000 examinations (65/30,812). CDR showed a significant independent positive association with years since breast cancer diagnosis (adjusted OR, 1.03; 95% CI, 1.01-1.05; p < .001), being lowest more than 2 to up to 3 years after diagnosis (4.9 per 1000 examinations) and highest more than 8 to up to 9 years after diagnosis (11.2 per 1000 examinations). AIR showed a significant independent negative association with years since breast cancer diagnosis (adjusted OR, 0.99; 95% CI, 0.98-1.00; p = .01), being highest 1 year or less after diagnosis (7.5%) and lowest more than 5 to up to 6 years after diagnosis (5.0%). CONCLUSION. Among 8090 patients with a prior breast cancer diagnosis, even though the AIR was higher during the year after diagnosis compared with subsequent years, the AIR remained acceptably low (< 10%) in all years. CLINICAL IMPACT. These results support the study institution's mammographic surveillance protocol for patients with a prior breast cancer diagnosis of returning immediately to DBT screening.

Retained Biopsy Site Markers After Breast Lesion Surgical Resection: Associations With Residual Malignancy

BACKGROUND. Biopsy site markers (BSMs) placed during image-guided core needle biopsy (CNB) are typically targeted for surgical excision, along with the breast imaging abnormality. Retained BSMs raise concern of incomplete resection of the breast abnormality. OBJECTIVE. The purpose of our study was to assess the frequency of residual malignancy in patients with retained BSMs identified on the initial mammography performed after breast lesion surgical excision. METHODS. This retrospective study included 30 patients (median age, 59 years) who underwent surgical resection between August 2015 and April 2022 of a borderline, high-risk, or malignant breast lesion after CNB and technically adequate preoperative image-guided localization, in whom the initial postoperative mammography report described a retained nonmigrated BSM. EMR data were extracted. The index pathology from CNB and initial surgical resection was classified as malignant or nonmalignant. The presence of residual malignancy after initial surgical resection required pathologic confirmation from subsequent tissue sampling; the absence of residual malignancy required 2 years of benign imaging follow-up. RESULTS. Thirteen specimen radiographs were interpreted intraoperatively by a surgeon with later radiologist interpretation, and 17 underwent real-time radiologist interpretation. Eighteen patients had malignant index pathology from the initially resected lesion. The frequency of residual malignancy on subsequent follow-up after initial surgical resection was higher in patients with malignant than nonmalignant index pathology (39% [7/18] vs 0% [0/12], respectively; p = .02). Among patients with malignant index pathology, the frequency of residual malignancy was higher in those without, than with, malignancy in the initial surgical specimen (80% [4/5] vs 23% [3/13]; p = .047). Also in these patients, the frequency of a positive interpretation of the initial postoperative mammography (BI-RADS category 4 or 6) was not significantly different between those with and without residual malignancy (57% [4/7] vs 55% [6/11]; p > .99). CONCLUSION. Patients with retained BSMs associated with malignant index lesions are at substantial risk of having residual malignancy. Initial postoperative mammography is not sufficient for excluding residual malignancy. CLINICAL IMPACT. Retained BSMs associated with index malignancy should be considered suspicious for residual malignancy. In this scenario, timely additional tissue sampling targeting the retained BSM is warranted, given the greater-than-2% chance of malignancy. Active surveillance is a reasonable management strategy in patients with retained BSMs from nonmalignant index lesions.

What Should We Know in Postoperative Surveillance Imaging After Oncoplastic Breast-Conserving Surgery with Pellet-Type Acellular Dermal Matrix?

RATIONALE AND OBJECTIVES

The aim of this study was to evaluate the usual postoperative imaging findings among patients who underwent oncoplastic breast-conserving surgery (BCS) with acellular dermal matrix (ADM) and to assess the clinical utility of mammography (MG) and ultrasonography (US) in follow-ups.

MATERIALS AND METHODS

This retrospective review of our prospectively collected database of patients who underwent oncoplastic BCS with ADM was conducted with IRB approval and in HIPPA compliance. A total of 105 patients whose follow-up MG and US studies over 2years after surgery were available were included in this study. Postoperative imaging findings were analyzed based on sequential MG and US follow-ups. The clinical outcomes and pathological data were also reviewed. The diagnostic performance of MG and US for postoperative surveillance was assessed.

RESULTS

On MG, ADM presented as an oval (99/105, 94.3%), circumscribed/obscured (65/105, 61.9%), and high-density (56/105, 53.3%) mass with calcifications (54/105, 51.4%). On US, the ADM-filled cavity presented as an oval (93/105, 88.6%), circumscribed (70/105, 66.7%), heterogenous echoic (65/105, 61.9%) mass with marginal/posterior acoustic shadowing (95/105, 90.5%) on US. During the follow-up period (mean, 46.1months; range, 26-58 months), four tumor recurrences were diagnosed (4/105, 3.8%). One tumor recurrence detected on MG presented as microcalcifications (1/4, 25%), which were differentiated from benign postoperative calcifications due to their suspicious morphology and location. Two additional recurrences (2/4, 50%), which were MG-negative small masses or intraductal lesions, were detected on US. One tumor recurrence was missed on both MG+US and was detected by magnetic resonance imaging performed at clinician's request. The sensitivity and specificity of MG, US, and MG+US for postoperative surveillance were 25%, 50% and 75% and 100%, 98% and 98%, respectively.

CONCLUSION

Recognition and adequate interpretation of the usual findings after oncoplastic BCS with ADM insertion are important in postoperative imaging surveillance. The sole use of MG is not sufficient for the detection of mass-type tumor recurrence due to the density of inserted ADM fillers. Therefore, the combined use of MG+US could serve as a useful postoperative surveillance tool with increased sensitivity in this population.

Challenges and Changes of the Breast Cancer Screening Paradigm

Since four decades mammography is used for early breast cancer detection in asymptomatic women and still remains the gold standard imaging modality. However, population screening programs can be personalized and women can be divided into different groups based on risk factors and personal preferences. The availability of new and evolving imaging modalities, for example, digital breast tomosynthesis, dynamic-contrast-enhanced magnetic resonance imaging (MRI), abbreviated MRI protocols, diffusion-weighted MRI, and contrast-enhanced mammography leads to new challenges and perspectives regarding the feasibility and potential harms of breast cancer screening. The aim of this review is to discuss the current guidelines for different risk groups, to analyze the recent published studies about the diagnostic performance of the imaging modalities and to discuss new developments and future perspectives. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 6.

Mammographic calcifications undergoing percutaneous biopsy: outcome in women with and without a personal history of breast cancer

PURPOSE

To compare the positive predictive values (PPVs) of BI-RADS categories used to assess pure mammographic calcifications in women with and without a previous history of breast cancer (PHBC).

MATERIALS AND METHODS

In this retrospective study, all consecutive pure mammographic calcifications (n = 320) undergoing a stereotactic biopsy between 2016 and 2018 were identified. Mammograms were evaluated in consensus by two radiologists according to BI-RADS and blinded to patient history and pathology results. Final pathologic results were used as the standard of reference. PPV of BI-RADS categories were compared between the two groups. Data were evaluated using standard statistics, Mann-Whitney U tests and Chi-square tests.

RESULTS

Two hundred sixty-eight patients (274 lesions, median age 54 years, inter-quartile range, 50-65 years) with a PHBC (n = 46) and without a PHBC (n = 222) were included. Overall PPVs were the following: BI-RADS 2, 0% (0 of 56); BI-RADS 3, 9.1% (1 of 11); BI-RADS 4a, 16.2% (6 of 37); BI-RADS 4b, 37.5% (48 of 128); BI-RADS 4c, 47.3% (18 of 38) and BI-RADS 5, 100% (4 of 4). The PPV of BI-RADS categories was similar in patients with and without a PHBC (P = .715). Calcifications were more often malignant in patients with a PHBC older than 10 years (47.3%, 9 of 19) compared to 1-2 years (25%, 1 of 4), 2-5 years (20%, 2 of 10) and 5-10 years (0%, of 13) from the first breast cancer (P = .005).

CONCLUSION

PPV of mammographic calcifications is similar in women with or without PHBC when BI-RADS classification is strictly applied. A higher risk of malignancy was observed in patients with a PHBC longer than 10 years.

Comparison of Abbreviated Breast MRI vs Digital Breast Tomosynthesis for Breast Cancer Detection among Women with a History of Breast Cancer

RATIONALE AND OBJECTIVES

To compare the diagnostic performance of abbreviated breast MRI (AB-MRI) and digital breast tomosynthesis (DBT) in women with a personal history (PH) of breast cancer as a postoperative screening tool.

MATERIALS AND METHODS

A total of 471 patients who completed both DBT and AB-MRI examinations were included in this study (median age, 54.5 years). The detected cancer characteristics were analyzed. The cancer detection rate (CDR), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and area under the curve (AUC) were calculated by receiver operating characteristic (ROC) curve analysis.

RESULTS

Eleven malignancies were diagnosed, and most of the detected cancers were stage I (7 of 11, 63.6%). Eight were invasive ductal carcinomas (IDC), and 3 were ductal carcinoma in situ (DCIS). Of the 11 recurrences, 6 malignancies were detected by DBT, and 11 were detected by AB-MRI. AB-MRI detected all 8 IDC and 3 DCIS lesions, and DBT detected 6 of 8 IDC lesions. The CDRs for DBT and AB-MRI screenings were 12.7 and 23.4 per 1,000 women, respectively. The sensitivity, specificity, PPV, NPV, and accuracy of DBT versus AB-MRI were 54.6% versus 100%, 97.6% versus 96.5%, 35.3% versus 40.7%, 98.9% versus 100%, and 96.6% versus 96.6%, respectively. AB-MRI showed a higher AUC value (0.983) than DBT (0.761) (p = 0.0049).

CONCLUSION

AB-MRI showed an improved CDR, especially for invasive cancer. The diagnostic performance of AB-MRI was superior to that of DBT with high sensitivity and PPV without sacrificing specificity in women with a PH of breast cancer.

Screening MRI in Women at Intermediate Breast Cancer Risk: An Update of the Recent Literature

Guidelines issued by the American Cancer Society (ACS) in 2007 recommend neither for nor against screening MRI in women at intermediate breast cancer risk (15%–20%), including those with dense breast tissue, a history of lobular neoplasia or atypical ductal hyperplasia (ADH), or a prior breast cancer, because of scarce supporting evidence about the utility of MRI in these specific patient populations. However, since the issuance of the ACS guidelines in 2007, multiple investigations have found that women at intermediate risk may be suitable candidates for screening MRI, given the high detection rates of early-stage cancers and acceptable false-positive rates. For women with dense breast tissue, the Dense Tissue and Early Breast Neoplasm Screening trial reported that the incremental cancer detection rate (CDR) by MRI exceeded 16 cancers per 1000 examinations but decreased in the second round of screening; this decrease in CDR, however, occurred alongside a marked decrease in the false-positive rate. For women with lobular neoplasia or ADH, single-institution retrospective analyses have shown CDRs mostly ranging from 11 to 16 cancers per 1000 MRI examinations, with women with lobular carcinoma in situ benefitting more than women with atypical lobular hyperplasia or ADH. For patients with a prior breast cancer, the cancer yield by MRI varies widely but mostly ranges from 8 to 20 cancers per 1000 examinations, with certain subpopulations more likely to benefit, such as those with dense breasts. This article reviews and summarizes more recent studies on MRI screening of intermediate-risk women.

Nipple-sparing Mastectomy: What the Radiologist Should Know

Nipple-sparing mastectomy (NSM) is increasingly offered to patients undergoing treatment of breast cancer and prophylaxis treatment for reduction of breast cancer risk. NSM is considered oncologically safe for appropriately selected patients and is associated with improved cosmetic outcomes and quality of life. Accepted indications for NSM have expanded in recent years, and currently only inflammatory breast cancer or malignancy involving the nipple is considered an absolute contraindication. Neoplasms close to and involving the nipple areolar complex are common, and cancer of the lactiferous ducts can spread to the nipple. Therefore, accurate determination of nipple involvement at imaging examinations is critical to identifying appropriate candidates for NSM and preventing local recurrence. Multiple imaging features have been described as predictors of nipple involvement, with tumor to nipple distance, enhancement between the index malignancy and the nipple, and nipple retraction demonstrating the highest predictive values. These features can be assessed at multimodality breast imaging, particularly at breast MRI, which demonstrates high specificity and negative predictive value for determining nipple involvement in malignancy. Online supplemental material is available for this article. ^©RSNA, 2022.

Ipsilateral microcalcifications after breast-conserving surgery: is it possible to differentiate benign from malignant calcifications?

AIM

To analyse stereotactic biopsies of microcalcifications in patients with previous ipsilateral breast-conserving surgery (BCS) to identify the positivity rate, assess for an association between the patient's primary cancer or mammographic appearances of the microcalcifications, and the risk of recurrence.

MATERIALS AND METHODS

Relevant patients from 2018-2020 were identified via a retrospective review of the prospectively maintained radiological procedure database. Clinicopathological features of the patients' primary tumour and new calcifications were obtained from the hospital electronic patient record system and the national integrated medical imaging system.

RESULTS

Thirty-one percent of recurrences post-ipsilateral BCS presented as isolated microcalcifications on mammography. Fifty-three percent of patients undergoing stereotactic biopsy of ipsilateral calcifications had recurrence. A positive margin status was associated with new or recurrent malignancy. There was no significant correlation between oestrogen-receptor status, sentinel lymph node status, adjuvant radiotherapy or chemotherapy and the risk of recurrence. Calcifications within the tumour bed were more likely to be benign while calcifications within the same quadrant but remote from the tumour bed were more likely malignant. All coarse calcifications were benign while 67% of fine linear/fine linear branching and 89% of fine pleomorphic calcifications were malignant.

CONCLUSION

Increased time since diagnosis, positive margin status, fine pleomorphic and fine linear calcifications in the same quadrant as the tumour bed were associated with malignancy. Patients with coarse calcifications and calcifications within the tumour bed may avoid stereotactic biopsy and undergo short-interval surveillance.

Mammographic Surveillance After Breast Conserving Therapy: Impact of Digital Breast Tomosynthesis and Artificial Intelligence-Based Computer-Aided Detection

Background: Postoperative mammograms present interpretive challenges due to postoperative distortion and hematomas. The application of digital breast tomosynthesis (DBT) and artificial intelligence-based computer-aided detection (AI-CAD) after breast concerving therapy (BCT) has not been widely investigated. Objective: To assess the impact of additional DBT or AI-CAD on recall rate and diagnostic performance in women undergoing mammographic surveillance after BCT. Methods: This retrospective study included 314 women (mean age 53.2±10.6 years; 4 with bilateral breast cancer) who underwent BCT followed by DBT (mean interval from surgery to DBT of 15.2±15.4 months). Three breast radiologists independently reviewed images in three sessions: digital mammography (DM), DM with DBT (DM+DBT), and DM with AI-CAD (DM+AI-CAD). Recall rates and diagnostic performance were compared between DM, DM+DBT, and DM+AI-CAD, using readers' mean results. Results: Of the 314 women, 6 breast recurrences (3 ipsilateral, 3 contralateral) developed at the time of surveillance mammography. Ipsilateral breast recall rate was lower for DM+AI-CAD (1.9%) than for DM (11.2%) or DM+DBT (4.1%) (p<.001). Contralateral breast recall rate was lower for DM+AI-CAD (1.5%, p<.001) than for DM (6.6%) but not DM+DBT (2.7%, p=.08). In ipsilateral breast, accuracy was higher for DM+AI-CAD (97.0%) than for DM (88.5%) or DM+DBT (94.8%) (p<.05); specificity was higher for DM+AICAD (98.3%) than for DM (89.3%) or DM+DBT (96.1%) (p<.05); sensitivity was lower for DM+AI-CAD (22.2%) than for DM (66.7%, p=.03) but not DM+DBT (22.2%, p>.99). In contralateral breast, accuracy was higher for DM+AI-CAD (97.1%) than for DM (92.5%, p<.001) but not DM+DBT (96.1%, p=.25); specificity was higher for DM+AI-CAD (98.6%) than for DM (93.7%, p<.001) but not DM+DBT (97.5%) (p=.09); sensitivity was not different between DM (33.3%), DM+DBT (22.2%), and DM+AI-CAD (11.1%) (p>.05). Conclusion: After BCT, adjunct DBT or AI-CAD reduced recall rates and improved accuracy in the ipsilateral and contralateral breasts compared with DM. In the ipsilateral breast, addition of AI-CAD resulted in lower recall rate and higher accuracy than addition of DBT. Clinical Impact: AI-CAD may help address the challenges of post-BCT surveillance mammograms.

Time to development and imaging features of new calcifications in the treated breast after breast-conserving therapy

OBJECTIVE

The purpose of our study was to analyze the time to development, malignancy rate, location, and mammographic features of new calcifications in the treated breast after breast-conserving therapy (BCT).

MATERIALS AND METHODS

In this HIPAA-complaint, IRB-approved retrospective study, we reviewed the records of patients treated with BCT at our institution with breast-conserving surgery performed between January 1, 2009 and December 31, 2010. A total of 735 breasts in 732 women were included in our study cohort. Factors analyzed included rate of development of new calcifications, malignancy rate of new calcifications, the time between completion of radiation therapy and development of new calcifications, imaging features of new calcifications, and location of the new calcifications in relation to the primary malignancy.

RESULTS

During follow-up, new calcifications developed in 155 of the 735 treated breasts (21.1%) and 155 of the 732 women (21.2%). After excluding two cases that were lost to follow-up, the malignancy rate of new calcifications was 5.2% (8/153; 95% CI: 2.3% to 10.0%). The median time to development of the benign calcifications was 27 months (range, 2 to 91 months) and of the malignant calcifications was 41 months (range, 11 to 57 months). Of the 20 (13.1%) cases of new calcifications categorized as BI-RADS 3 (probably benign), all were benign on follow-up (19 cases) or on biopsy (1 case). Of the 51 BI-RADS 4 (suspicious) cases, 8 (16%) were biopsy-proven malignant. The malignancy rate was the highest in fine pleomorphic 100% (1/1), followed by amorphous 17%, (5/29), coarse heterogeneous 8% (2/26) and typically benign 0 (0/97) calcifications (p < 0.0001). The malignancy rate was 1.5% (2/137) for new calcifications within the lumpectomy site vs. 37.5% (6/16) for new calcifications outside the lumpectomy site (p < 0.0001) and was 3.4% (5/147) for new calcifications at or within the same quadrant as the lumpectomy site vs. 50.0% (3/6) for new calcifications in a different quadrant from the lumpectomy site (p=0.002).

CONCLUSION

Most new calcifications that developed in the treated breast after BCT were benign. Evaluation of morphology and distribution of those calcifications is imperative. New calcifications in the treated breast outside the lumpectomy site are more likely to be malignant and should be viewed with greater suspicion. Benign calcifications developed earlier than malignant calcifications, but the time courses overlapped.

Postoperative Imaging Appearance of an Implantable Three-dimensional Bioabsorbable Tissue Marker After Breast Surgery: Initial Experience at a Single Institution

OBJECTIVE

Three-dimensional bioabsorbable tissue marker (BTM) placement during breast surgery is performed for the purpose of improved surgical cavity delineation for radiotherapy and improved cosmetic outcome. The purpose of this study is to evaluate the postsurgical imaging findings of BTM.

METHODS

This Institutional Review Board-approved retrospective review included all patients implanted with BTM at breast surgery from January 2017 to September 2018. Demographics, tumor characteristics, imaging, and histologic findings were evaluated. Medical records were reviewed during a three-year period to evaluate for tumor recurrence.

RESULTS

Ninety-seven patients had BTM implanted, of which 76 patients had imaging follow-up of at least 1 year. Of the 76 patients who had mammographic follow-up, 3 (3.9%) developed suspicious microcalcifications requiring biopsy, yielding ductal carcinoma in-situ in 2 patients and benign calcifications in 1 patient. Of 61 patients who had sonographic follow-up, 44 (72.1%) patients had complex fluid collections containing avascular, heterogeneously hyperechoic solid components, which remained stable or decreased in size over time; no recurrent tumors were found in this group. One patient (1.6%) had a vascular solid mass, which yielded recurrent papilloma. Four (6.6%) patients developed irregular hypoechoic masses at the surgical site, one of which corresponded with a developing asymmetry mammographically; biopsy yielded fibromatosis. Tissue sampling of the remaining three cases yielded invasive ductal carcinoma, fat necrosis, and radiation changes, respectively.

CONCLUSION

Accurate identification of the expected postoperative imaging appearance of BTM may prevent unnecessary biopsy. Suspicious findings necessitating biopsy are pleomorphic calcifications, developing asymmetry and vascular and irregular hypoechoic masses.

Spectrum of Multimodality Findings in Post-surgical Breast Cancer Imaging

BACKGROUND

Breast cancer is the commonest cancer affecting Malaysian women, accounting for an estimated 30% of all new cancer diagnosed annually. Improvements in breast cancer management have increased the breast cancer survival rate in Malaysia. Clinical and radiological surveillance of the treated breast is vital, as early detection of recurrence improves patient's survival rate.

DISCUSSION

As surgery and radiotherapy alter the appearance of the breasts, distinguishing between recurrence and benign post-surgical changes can be challenging radiologically due to overlapping features. Despite this, differentiation between these two entities is usually possible by recognizing characteristic features of post-treatment sequelae and the evolution of the appearance of the conservatively treated breast by comparing interval findings on serial studies.

CONCLUSION

This pictorial review aims to describe the typical and unusual features of post-treated breasts in the multimodality imaging workup of an established breast care centre in a teaching hospital in Malaysia.

Digital Mammographic Features of Breast Cancer Recurrences and Benign Lesions Mimicking Malignancy Following Breast-Conserving Surgery and Radiation Therapy

Mammography after breast-conserving surgery and radiation therapy is an important tool for followup. Early diagnosis of local recurrence enables prompt treatment decisions, which may affect patient prognosis. For complicated post-treatment changes, radiologists sometimes have difficulties in interpreting follow-up mammography. Fat necrosis, dystrophic calcifications, suture calcification features, breast edema, seroma and distorted breast are benign changes related to treatment. These findings may mimic or hide tumor recurrence making it difficult to diagnose recurrences or prevent inappropriate biopsies. Recurrent tumors in follow-up mammography show several typical findings such as increasing asymmetric density, enlarging mass, reappearance of breast edema, and micro-calcifications. The purpose of this pictorial review is to demonstrate and discuss mammographic findings of recurrent tumors and important post-treatment changes that may mimic benign or malignant lesions, also using breast ultrasound images or breast magnetic resonance images. Recognizing post-treatment changes may help radiologists to more effectively identify candidates for suspected local recurrences.

Fat necrosis in the Breast: A systematic review of clinical

Breast fat necrosis (FN) originates from aseptic fat saponification, which is a typical lipid cyst or a spiculated lesion called mammographic presentation which mimics malignancy. In order to avoid biopsy, it would be necessary to identify the spectrum of fat necrosis appearances. A systematic research was conducted in October 2018 by using PubMed, MEDLINE, Embase, Google Scholar databases and Google to search for science literature published after 2004. Therefore, the aim of this systematic review, it is that the FN can provide radiologists, surgeons, and oncologists with better insight and help them manage the condition efficiently.

Imaging of the treated breast post breast conservation surgery/oncoplasty: Pictorial review

Mammographic appearance of the normal breast is altered in the post-operative setting. It is essential to be aware of the normal findings as well as to identify features of recurrent disease with particular emphasis on radiological-pathological concordance. Digital breast tomosynthesis and volumetric breast density add incremental value in this clinical setting. We present a pictorial review of various cases to illustrate normal post-operative findings as well as mammographic features suspicious for recurrent disease.

Magnetic Resonance Imaging after Breast Oncoplastic Surgery: An Update

Breast-oncoplastic surgery, allowing local tumor control and a better cosmetic outcome, is oncologically safe when applied to early-stage breast cancer. Breast cancer recurrence following conservative therapy may occur during the first 5 years after treatment, with a peak incidence after 2 years. Therefore, during the follow-up period, patients undergo a series of ultrasound (US) and mammographic examinations. However, after surgery and radiation therapy, several modifications occur in the treated breast, causing difficulties in image interpretation, especially when local recurrence is suspected. Although not included in routine follow-up, magnetic resonance imaging (MRI) is often used in clinical practice, being considered more sensitive than the conventional imaging examinations in discriminating between postsurgical tissue modifications and tumor recurrence. In this review article, we analyze expected and pathologic breast MRI findings after conservative oncoplastic surgery compared to US and mammographic findings in order to distinguish local recurrence and avoid potential pitfalls in image interpretation.

Analysis of stereotactic biopsies performed on suspicious calcifications identified within 24 months after completion of breast conserving surgery and radiation therapy for early breast cancer: Can biopsy be obviated?

BACKGROUND

To determine the cancer yield of stereotactic biopsy of suspicious calcifications identified within 24 months after breast conservation therapy (BCT).

METHODS

Retrospective review of stereotactic biopsies performed during 2009-2013 for suspicious calcifications in the ipsilateral breast of patients who completed BCT.

RESULTS

94/2773 (3.4%) had stereotactic biopsies for suspicious calcifications in the ipsilateral breast; 7/94 (7.4%) had DCIS (6) or invasive (1) cancer; 5/7 occurred in the same breast quadrant as the primary. All 7 originally had negative surgical margins (≥2 mm); 6 received whole breast irradiation, and 2 received adjuvant chemotherapy + endocrine therapy. Median time to detection was 11 months (range, 6-20 months). There was a strong association between calcification morphology (particularly pleomorphic) and likelihood of malignancy (p = 0.008).

CONCLUSIONS

Stereotactic biopsy of calcifications identified within 24 months post-BCT has a 7% cancer yield. Tissue biopsy should be performed rather than imaging followup alone when breast calcifications have suspicious morphology.

Breast ultrasonography for detection of metachronous ipsilateral breast tumor recurrence

BACKGROUND

Early detection of recurrence improves the survival rate of patients treated with breast conservation therapy (BCT). Therefore, ultrasonography (US) may be useful for metachronous ipsilateral breast tumor recurrence (MIBTR) obscured on mammography by dense breast tissue and distortion.

PURPOSE

To evaluate clinical, radiologic, and pathologic findings of MIBTR retrospectively, and to assess the role of surveillance US additional to mammography for MIBTR detection.

MATERIAL AND METHODS

During 2000 to 2012, 28 MIBTR were collected and reviewed among 2958 women treated for primary breast cancer with conservation surgery. The detection rates of imaging studies for identifying metachronous ipsilateral lesions were assessed and compared. MIBTR tumor staging was evaluated according to imaging modality for detection of MIBTR, palpability, and recent imaging surveillance.

RESULTS

No significant difference was observed in the detection rate between mammography and US for overall MIBTR (84.2% vs. 85.7%; P = 0.898) or non-palpable MIBTR (88.2% vs. 81.0%; P = 0.566). US alone identified 33.3% of non-palpable MIBTRs (seven of 21). Among these cases, two had negative mammograms. All 14 MIBTRs with recent imaging surveillance were stage T2 or less, and all seven MIBTRs detected by US alone were in situ or T1; 33% of MIBTRs without recent imaging surveillance were T3 or T4.

CONCLUSION

The overall MIBTR detection rate by US was not higher than the detection rate of mammography, although combined surveillance with US and mammography found MIBTRs slightly earlier than mammography alone.

2-(fluorine-18)-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography after breast conserving surgery: Correlation with molecular markers of breast cancer

Aim:

To investigate the role of 2-(fluorine-18)-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) early after breast-conserving surgery (BCS) in patients with breast cancer (BC) and whether we can determine which molecular biomarkers of breast carcinoma put the patients at risk.

Materials and Methods:

This retrospective study involved 88 patients with histologically proven T1 or T2 BC, who were treated with BCS and underwent ¹⁸F-FDG PET/CT study. The correlation between biological markers (estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 [HER2], and Ki-67) of the primary tumor and ¹⁸F-FDG PET/CT findings was analyzed.

Results:

¹⁸F-FDG PET/CT demonstrated the presence of BC disease (locoregional disease [LRD], distant metastases, or contralateral BC) in 26 of 88 patients (29.5%). Regarding immunohistochemical profiles, BC expressing high levels of Ki-67 were associated with an increased percentage of LRD, which was the major recurrence pattern on ¹⁸F-FDG PET/CT. Although the BC disease was observed more commonly in patients with HER2 positivity compared to those of HER2 negative, the difference did not reach statistical significance. The patients with T2 tumor or a higher histopathological grade had a higher percentage of BC disease.

Conclusions:

This study demonstrated that patients with early stage BC treated with BCS have a remarkable risk of the presence of BC even early after surgery, and there was a clinically important relationship between ¹⁸F-FDG PET/CT findings and biological markers of BC. These findings suggest that high-risk molecular biomarkers (Ki-67, HER2) can be taken into account in the decision-making the process for both preoperative imaging and planning of the surgical approach.

A prospective study comparing digital breast tomosynthesis with digital mammography in surveillance after breast cancer treatment

BACKGROUND

Although the benefit of adjunct digital breast tomosynthesis (DBT) is established in population screening, its benefit in surveillance after breast cancer treatment is not well defined. We prospectively evaluated whether the addition of DBT to digital mammography (DM) reduced the rate of indeterminate findings compared to DM alone in patients after breast cancer treatment.

METHODS

Patients had both DM and DBT for routine surveillance. Two-dimensional synthesised mammogram (SM) was generated for each patient from DBT data. DM, SM, and DBT images were read for each patient by one of four radiologists credentialed for DBT. We compared the rates of indeterminate findings between DM+DBT with DM alone in patients with a range of breast densities and between DM and SM.

RESULTS

A total of 618 patients and 1069 breasts were analysed. The rates of indeterminate findings for DM+DBT versus DM alone were 10.5% and 13.1%, respectively (p=0.018). In breasts treated with surgery and radiotherapy (n=558), the corresponding rates of indeterminate findings were 4.9% and 6.9%, respectively (p=0.039). The rate of indeterminate findings for DM+DBT increased with increasing breast density (p=0.019). There was no significant difference in the rates of indeterminate findings between DM and SM (13.1% versus 11.5%, p=0.1).

CONCLUSION

The addition of DBT to DM reduced the rate of indeterminate findings in surveillance of patients after breast cancer treatment. Further research is required to confirm whether DBT and SM could replace DM for patients undergoing surveillance.

Radiation-Associated Angiosarcoma of the Breast: What the Radiologist Needs to Know

OBJECTIVE

The purpose of this article is to describe the diagnosis, treatment, and follow-up of radiation-associated angiosarcoma (RAS) of the breast.

CONCLUSION

Radiologists play an important role in the diagnosis of RAS, which may initially present clinically as erythema, ecchymosis, or skin thickening. Conventional imaging with mammography and ultrasound is less sensitive than MRI for the diagnosis of RAS. Follow-up CT is important to monitor treatment response.

Comparison of Mammographic Changes Across Three Different Fractionation Schedules for Early-Stage Breast Cancer

PURPOSE

As the use of hypofractionated breast radiation therapy (RT) increases, so will the need for long-term data on post-RT mammographic changes. The purpose of the present study was to longitudinally compare the incidence of common mammographic sequelae seen after breast conserving surgery and RT in patients treated with accelerated partial breast irradiation (APBI), hypofractionated whole breast irradiation (HWBI), and conventionally fractionated whole breast irradiation (WBI).

METHODS AND MATERIALS

Patients treated with either APBI or HWBI after breast conserving therapy and with ≥3 mammograms of the treated breast were identified. They were matched 1:1 by age ±5 years to patients treated with WBI. The mammograms were evaluated for common post-RT breast findings by a mammographer who was unaware of the treatment. The outcomes were analyzed using a cumulative logistic regression model; P<.05 indicated statistically significance.

RESULTS

Of 89 patients treated with RT from 2006 to 2011, 29 had received APBI, 30 had received HWBI, and 30 had received WBI. Their median age was 60 years (range 33-83). A total of 605 mammograms were evaluated, with a median follow-up of 48 months. The treatment technique did not affect the severity of architectural distortion when the groups were evaluated longitudinally. The likelihood of finding skin thickening decreased with increasing follow-up duration (odds ratio 0.6; P<.001) adjusted for fractionation schemes. No differences were seen with respect to changes in skin thickening, fluid collections, or calcifications among the treatment groups, after adjustment for the follow-up time. The clinical characteristics, including age, race, T stage, and chemotherapy use, were not linked to the likelihood of finding several mammographic phenomena over time.

CONCLUSIONS

Although specific post-treatment imaging findings evolved over time, RT fractionation did not alter the relative incidence or severity of architectural distortion, skin thickening, fluid collections, or calcifications. These findings will be useful to both radiologists and radiation oncologists when counseling patients regarding follow-up studies after RT.

Calcifications and tungsten deposits after breast-conserving surgery and intraoperative radiotherapy for breast cancer

AIM

To describe the presence of atypical calcifications on post-operative mammography after breast-conserving surgery (BCS) and intraoperative radiotherapy (IORT).

MATERIALS AND METHODS

We retrospectively include all patients followed after BCS and IORT for breast cancer (n=271). All follow-up mammograms at 6 months after surgery were retrospectively evaluated by two board-certified radiologists. The radiologists had to notify the presence or the absence of atypical calcifications.

RESULTS

Five patients had on follow-up mammography the presence of atypical calcifications. Two patients had a stereotactic breast biopsy. The pathologic examination showed the presence of small tungsten particles located in the breast parenchyma.

CONCLUSION

The presence of atypical calcifications after BCS and IORT, presenting as multiple, scattered, round calcifications, should be rated as BIRADS 2 and do not require biopsy. They corresponded on tungsten deposits.

Does accelerated hypofractionated adjuvant whole-breast radiotherapy increase mammographic density or change mammographic features?

OBJECTIVE

To compare mammographic features before and after accelerated hypofractionated adjuvant whole-breast radiotherapy (AWB-RT) and to evaluate possible appearance of modifications.

METHODS

A retrospective review of 177 females before and after an AWB-RT treatment (follow-up ranging from 5 to 9 years) was performed by four radiologists focused in breast imaging who independently evaluated diffuse mammographic density patterns and reported on possible onset of focal alterations; modifications in density and fibrosis with parenchymal distortion were deemed as indicators of AWB-RT treatment impact in breast imaging.

RESULTS

Prevalent mammographic density (D) patterns in the 177 females evaluated were according to the American College of Radiology-Breast Imaging Reporting and Data System (ACR-BIRADS): D1, fibroadipose density (score percentage from 55.9% to 43.5%); and D2, scattered fibroglandular density (from 42.9% to 32.7%). No change in diffuse mammographic density and no significant difference in mammographic breast parenchymal structure were observed. "No change" was reported with score percentage from 87% to 79.6%. Appearance of fibrosis with parenchymal distortion was reported by all radiologists in only two cases (1.1%, p = 0.3); dystrophic calcification was identified with percentage score from 2.2% to 3.3% (small type) and from 9.6% to 12.9% (coarse type).

CONCLUSION

No statistically significant changes in follow-up mammographies 5-9 years after AWB-RT were detected, justifying large-scale selection of AWB-RT treatment with no risk of altering radiological breast parameters of common use in tumour recurrence detection.

ADVANCES IN KNOWLEDGE

The hypofractionated radiotherapy (AWB-RT treatment) is a new proven, safe and effective modality in post-operative patients with early breast cancer with excellent local control and survival. In our study, the absence of changes in mammographic density patterns and in breast imaging before and after AWB-RT treatment (up to 5-9 years after radiotherapy) justifies large-scale use of AWB-RT treatment without hindrance in tumour recurrence diagnosis.

An evaluation of post-lumpectomy recurrence rates: is follow-up every 6 months for 2 years needed?

BACKGROUND AND OBJECTIVES

There is currently debate about the optimal timing and frequency of mammography follow-up after breast-conserving therapy (BCT). The purpose of this study was to determine if 6-month intervals for the first 2 years following BCT offer benefit over annual screening.

METHODS

Three hundred ninety-nine patients who had lumpectomies between 1997 and 2009 and who were followed for at least 2 years with mammography were selected. The mammography yields for the first 2 years following BCT were compared to those of the general screening population. Also, patients were grouped as either compliant or noncompliant with the recommended 6-month intervals; Fischer's exact test was used to determine if there was a relationship between the grouping (compliant or noncompliant) and tumor recurrence.

RESULTS

Mammography yield was 0.94 and 2.87 per 1,000 for the first and second years, respectively, following surgery. Three hundred twenty-eight patients were categorized as compliant and 1 local recurrence was discovered in this group; 67 patients were labeled as noncompliant and 0 local recurrences were found in this group.

CONCLUSIONS

Mammography yield of cancer in the study population was not greater than the general population. There was no difference between the compliant and noncompliant groups regarding tumor recurrence.

The postconservation breast: part 2, Imaging findings of tumor recurrence and other long-term sequelae

OBJECTIVE

The objectives of this article are to highlight the imaging findings of tumor recurrence and other long-term potential sequelae after breast-conserving surgery and radiation therapy, including increased risk of infection and radiation-induced malignancies. The role of MRI as a problem-solving tool in evaluating the conservatively treated breast will also be discussed.

CONCLUSION

Imaging the treated breast presents challenges because of its limited compressibility and overlapping features of benign posttreatment alterations and tumor recurrence. After lumpectomy and radiation therapy, mammographic findings such as breast edema, skin thickening, fluid collections, architectural distortion, and calcifications have characteristic sequences of evolution toward stability. Changes in the imaging appearance after stability has been achieved--including increasing asymmetry, an enlarging mass, increasing edema or skin thickening, and the development of pleomorphic calcifications within or near the operative bed--should alert the radiologist to possible tumor recurrence. When mammography or sonography is indeterminate, MRI may be useful in excluding recurrence or providing a means for biopsy of a suspicious finding.