Diffusion Tensor Imaging for Characterizing Changes in Triple-Negative Breast Cancer During Neoadjuvant Systemic Therapy.

BACKGROUND: Assessment of treatment response in triple-negative breast cancer (TNBC) may guide individualized care for improved patient outcomes. Diffusion tensor imaging (DTI) measures tissue anisotropy and could be useful for characterizing changes in the tumors and adjacent fibroglandular tissue (FGT) of TNBC patients undergoing neoadjuvant systemic treatment (NAST). PURPOSE: To evaluate the potential of DTI parameters for prediction of treatment response in TNBC patients undergoing NAST. STUDY TYPE: Prospective. POPULATION: Eighty-six women (average age: 51 ± 11 years) with biopsy-proven clinical stage I-III TNBC who underwent NAST followed by definitive surgery. 47% of patients (40/86) had pathologic complete response (pCR). FIELD STRENGTH/SEQUENCE: 3.0 T/reduced field of view single-shot echo-planar DTI sequence. ASSESSMENT: Three MRI scans were acquired longitudinally (pre-treatment, after 2 cycles of NAST, and after 4 cycles of NAST). Eleven histogram features were extracted from DTI parameter maps of tumors, a peritumoral region (PTR), and FGT in the ipsilateral breast. DTI parameters included apparent diffusion coefficients and relative diffusion anisotropies. pCR status was determined at surgery. STATISTICAL TESTS: Longitudinal changes of DTI features were tested for discrimination of pCR using Mann-Whitney U test and area under the receiver operating characteristic curve (AUC). A P value <0.05 was considered statistically significant. RESULTS: 47% of patients (40/86) had pCR. DTI parameters assessed after 2 and 4 cycles of NAST were significantly different between pCR and non-pCR patients when compared between tumors, PTRs, and FGTs. The median surface/average anisotropy of the PTR, measured after 2 and 4 cycles of NAST, increased in pCR patients and decreased in non-pCR patients (AUC: 0.78; 0.027 ± 0.043 vs. -0.017 ± 0.042 mm2 /s). DATA CONCLUSION: Quantitative DTI features from breast tumors and the peritumoral tissue may be useful for predicting the response to NAST in TNBC. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 4.

A phase II study of neoadjuvant atezolizumab and nab-paclitaxel in patients with anthracycline-resistant early-stage triple-negative breast cancer.

PURPOSE: Neoadjuvant anti-PD-(L)1 therapy improves the pathological complete response (pCR) rate in unselected triple-negative breast cancer (TNBC). Given the potential for long-term morbidity from immune-related adverse events (irAEs), optimizing the risk-benefit ratio for these agents in the curative neoadjuvant setting is important. Suboptimal clinical response to initial neoadjuvant therapy (NAT) is associated with low rates of pCR (2-5%) and may define a patient selection strategy for neoadjuvant immune checkpoint blockade. We conducted a single-arm phase II study of atezolizumab and nab-paclitaxel as the second phase of NAT in patients with doxorubicin and cyclophosphamide (AC)-resistant TNBC (NCT02530489). METHODS: Patients with stage I-III, AC-resistant TNBC, defined as disease progression or a < 80% reduction in tumor volume after 4 cycles of AC, were eligible. Patients received atezolizumab (1200 mg IV, Q3weeks × 4) and nab-paclitaxel (100 mg/m2 IV,Q1 week × 12) as the second phase of NAT before undergoing surgery followed by adjuvant atezolizumab (1200 mg IV, Q3 weeks, × 4). A two-stage Gehan-type design was employed to detect an improvement in pCR/residual cancer burden class I (RCB-I) rate from 5 to 20%. RESULTS: From 2/15/2016 through 1/29/2021, 37 patients with AC-resistant TNBC were enrolled. The pCR/RCB-I rate was 46%. No new safety signals were observed. Seven patients (19%) discontinued atezolizumab due to irAEs. CONCLUSION: This study met its primary endpoint, demonstrating a promising signal of activity in this high-risk population (pCR/RCB-I = 46% vs 5% in historical controls), suggesting that a response-adapted approach to the utilization of neoadjuvant immunotherapy should be considered for further evaluation in a randomized clinical trial.

Quantitative Apparent Diffusion Coefficients From Peritumoral Regions as Early Predictors of Response to Neoadjuvant Systemic Therapy in Triple-Negative Breast Cancer.

BACKGROUND: Pathologic complete response (pCR) to neoadjuvant systemic therapy (NAST) in triple-negative breast cancer (TNBC) is a strong predictor of patient survival. Edema in the peritumoral region (PTR) has been reported to be a negative prognostic factor in TNBC. PURPOSE: To determine whether quantitative apparent diffusion coefficient (ADC) features from PTRs on reduced field-of-view (rFOV) diffusion-weighted imaging (DWI) predict the response to NAST in TNBC. STUDY TYPE: Prospective. POPULATION/SUBJECTS: A total of 108 patients with biopsy-proven TNBC who underwent NAST and definitive surgery during 2015-2020. FIELD STRENGTH/SEQUENCE: A 3.0 T/rFOV single-shot diffusion-weighted echo-planar imaging sequence (DWI). ASSESSMENT: Three scans were acquired longitudinally (pretreatment, after two cycles of NAST, and after four cycles of NAST). For each scan, 11 ADC histogram features (minimum, maximum, mean, median, standard deviation, kurtosis, skewness and 10th, 25th, 75th, and 90th percentiles) were extracted from tumors and from PTRs of 5 mm, 10 mm, 15 mm, and 20 mm in thickness with inclusion and exclusion of fat-dominant pixels. STATISTICAL TESTS: ADC features were tested for prediction of pCR, both individually using Mann-Whitney U test and area under the receiver operating characteristic curve (AUC), and in combination in multivariable models with k-fold cross-validation. A P value < 0.05 was considered statistically significant. RESULTS: Fifty-one patients (47%) had pCR. Maximum ADC from PTR, measured after two and four cycles of NAST, was significantly higher in pCR patients (2.8 ± 0.69 vs 3.5 ± 0.94 mm2 /sec). The top-performing feature for prediction of pCR was the maximum ADC from the 5-mm fat-inclusive PTR after cycle 4 of NAST (AUC: 0.74; 95% confidence interval: 0.64, 0.84). Multivariable models of ADC features performed similarly for fat-inclusive and fat-exclusive PTRs, with AUCs ranging from 0.68 to 0.72 for the cycle 2 and cycle 4 scans. DATA CONCLUSION: Quantitative ADC features from PTRs may serve as early predictors of the response to NAST in TNBC. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 4.

Early ultrasound evaluation identifies excellent responders to neoadjuvant systemic therapy among patients with triple-negative breast cancer.

BACKGROUND: Heterogeneity exists in the response of triple-negative breast cancer (TNBC) to standard anthracycline (AC)/taxane-based neoadjuvant systemic therapy (NAST), with 40% to 50% of patients having a pathologic complete response (pCR) to therapy. Early assessment of the imaging response during NAST may identify a subset of TNBCs that are likely to have a pCR upon completion of treatment. The authors aimed to evaluate the performance of early ultrasound (US) after 2 cycles of neoadjuvant NAST in identifying excellent responders to NAST among patients with TNBC. METHODS: Two hundred fifteen patients with TNBC were enrolled in the ongoing ARTEMIS (A Robust TNBC Evaluation Framework to Improve Survival) clinical trial. The patients were divided into a discovery cohort (n = 107) and a validation cohort (n = 108). A receiver operating characteristic analysis with 95% confidence intervals (CIs) and a multivariate logistic regression analysis were performed to model the probability of a pCR on the basis of the tumor volume reduction (TVR) percentage by US from the baseline to after 2 cycles of AC. RESULTS: Overall, 39.3% of the patients (42 of 107) achieved a pCR. A positive predictive value (PPV) analysis identified a cutoff point of 80% TVR after 2 cycles; the pCR rate was 77% (17 of 22) in patients with a TVR ≥ 80%, and the area under the curve (AUC) was 0.84 (95% CI, 0.77-0.92; P < .0001). In the validation cohort, the pCR rate was 44%. The PPV for pCR with a TVR ≥ 80% after 2 cycles was 76% (95% CI, 55%-91%), and the AUC was 0.79 (95% CI, 0.70-0.87; P < .0001). CONCLUSIONS: The TVR percentage by US evaluation after 2 cycles of NAST may be a cost-effective early imaging biomarker for a pCR to AC/taxane-based NAST.

Tumor necrosis by pretreatment breast MRI: association with neoadjuvant systemic therapy (NAST) response in triple-negative breast cancer (TNBC).

PURPOSE: To determine if tumor necrosis by pretreatment breast MRI and its quantitative imaging characteristics are associated with response to NAST in TNBC. METHODS: This retrospective study included 85 TNBC patients (mean age 51.8 ± 13 years) with MRI before NAST and definitive surgery during 2010-2018. Each MRI included T2-weighted, diffusion-weighted (DWI), and dynamic contrast-enhanced (DCE) imaging. For each index carcinoma, total tumor volume including necrosis (TTV), excluding necrosis (TV), and the necrosis-only volume (NV) were segmented on early-phase DCE subtractions and DWI images. NV and %NV were calculated. Percent enhancement on early and late phases of DCE and apparent diffusion coefficient were extracted from TTV, TV, and NV. Association between necrosis with pathological complete response (pCR) was assessed using odds ratio (OR). Multivariable analysis was used to evaluate the prognostic value of necrosis with T stage and nodal status at staging. Mann-Whitney U tests and area under the curve (AUC) were used to assess performance of imaging metrics for discriminating pCR vs non-pCR. RESULTS: Of 39 patients (46%) with necrosis, 17 had pCR and 22 did not. Necrosis was not associated with pCR (OR, 0.995; 95% confidence interval [CI] 0.4-2.3) and was not an independent prognostic factor when combined with T stage and nodal status at staging (P = 0.46). None of the imaging metrics differed significantly between pCR and non-pCR in patients with necrosis (AUC < 0.6 and P > 0.40). CONCLUSION: No significant association was found between necrosis by pretreatment MRI or the quantitative imaging characteristics of tumor necrosis and response to NAST in TNBC.

Functional Tumor Volume by Fast Dynamic Contrast-Enhanced MRI for Predicting Neoadjuvant Systemic Therapy Response in Triple-Negative Breast Cancer.

BACKGROUND: Dynamic contrast-enhanced (DCE) MRI is useful for diagnosis and assessment of treatment response in breast cancer. Fast DCE MRI offers a higher sampling rate of contrast enhancement curves in comparison to conventional DCE MRI, potentially characterizing tumor perfusion kinetics more accurately for measurement of functional tumor volume (FTV) as a predictor of treatment response. PURPOSE: To investigate FTV by fast DCE MRI as a predictor of neoadjuvant systemic therapy (NAST) response in triple-negative breast cancer (TNBC). STUDY TYPE: Prospective. POPULATION/SUBJECTS: Sixty patients with biopsy-confirmed TNBC between December 2016 and September 2020. FIELD STRENGTH/SEQUENCE: A 3.0 T/3D fast spoiled gradient echo-based DCE MRI ASSESSMENT: Patients underwent MRI at baseline and after four cycles (C4) of NAST, followed by definitive surgery. DCE subtraction images were analyzed in consensus by two breast radiologists with 5 (A.H.A.) and 2 (H.S.M.) years of experience. Tumor volumes (TV) were measured on early and late subtractions. Tumors were segmented on 1 and 2.5-minute early phases subtractions and FTV was determined using optimized signal enhancement thresholds. Interpolated enhancement curves from segmented voxels were used to determine optimal early phase timing. STATISTICAL TESTS: Tumor volumes were compared between patients who had a pathologic complete response (pCR) and those who did not using the area under the receiver operating curve (AUC) and Mann-Whitney U test. RESULTS: About 26 of 60 patients (43%) had pCR. FTV at 1 minute after injection at C4 provided the best discrimination between pCR and non-pCR, with AUC (95% confidence interval [CI]) = 0.85 (0.74,0.95) (P < 0.05). The 1-minute timing was optimal for FTV measurements at C4 and for the change between C4 and baseline. TV from the early phase at C4 also yielded a good AUC (95%CI) of 0.82 (0.71,0.93) (P < 0.05). DATA CONCLUSION: FTV and TV measured at 1 minute after injection can predict response to NAST in TNBC. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: 4.

MRI features of pseudoangiomatous stromal hyperplasia with histopathological correlation.

Pseudoangiomatous stromal hyperplasia (PASH), a rare, noncancerous lesion, is often an incidental finding on magnetic resonance imaging (MRI)-guided biopsy analysis of other breast lesions. We sought to describe the characteristics of PASH on MRI and identify the extent to which these characteristics are correlated with the amount of PASH in the pathology specimens. We identified 69 patients who underwent MRI-guided biopsies yielding a final pathological diagnosis of PASH between 2008 and 2015. We analyzed pre-biopsy MRI scans to document the appearance of the lesions of interest. All biopsy samples were classified as having ≤50% PASH or ≥51% PASH present on the pathological specimen. On MRI, 9 lesions (13%) appeared as foci, 19 (28%) appeared as masses with either washout or persistent kinetics, and 41 (59%) appeared as regions of nonmass enhancement. Of this latter group, 33 lesions (80%) showed persistent kinetic features. Masses, foci, and regions of nonmass enhancement did not significantly correlate with the percentage of PASH present in the biopsy specimens (P ≥ .05). Our findings suggest that PASH has a wide-ranging appearance on MRI but most commonly appears as a region of nonmass enhancement with persistent kinetic features. Our finding that most specimens had ≤50% PASH supports the notion that PASH is usually an incidental finding. We did not identify a definitive imaging characteristic that reliably identifies PASH.

Use of Mammographic Measurements to Predict Complications After Nipple-Sparing Mastectomy in BRCA Mutation Carriers.

BACKGROUND: There is limited data evaluating mastectomy skin flap complications of nipple-sparing mastectomy (NSM) in patients with BRCA gene mutations. The purpose of this study was to identify factors associated with post-operative complications in BRCA mutation carriers undergoing NSM. METHODS: Following institutional review board approval, we interrogated a prospectively collected institutional database for patients undergoing NSM who tested positive for BRCA1/2 mutations. Patient characteristics, preoperative details, and complications were evaluated. Digital mammogram was used to estimate the breast volume. RESULTS: From August 2009 to December 2017, 59 patients (2 males) with BRCA1/2 mutations underwent 114 NSMs. Ninety-two (80%) were risk-reduction surgeries. Thirty-two (28%) underwent single-stage reconstruction (24 autologous). The overall complication rate was 26.3% (N = 30), and 10.5% (N = 12) underwent unanticipated reoperation. 8.8% (N = 10) had full-thickness skin flap necrosis, 10.5% (N = 12) nipple necrosis, and 4.4% (N = 5) full-thickness nipple necrosis. These complications were associated with larger breast volume (799.4 cc vs. 544.1 cc, p < 0.001) and greater body mass index (27.8 vs. 24.3, p < 0.001). By univariate analysis, body mass index and breast volume greater than 675 cc were associated with significantly higher complication rate (odds ratios 1.2 and 4.5 respectively, p = 0.001). CONCLUSIONS: This study confirms that NSM in BRCA1/2 mutation carriers is associated with complications in one in four patients. Utilizing the preoperative mammograms to estimate breast size may be more helpful than breast cup size in counseling preoperatively the risks of complications.

Male Mammary Paget Disease: A Tale of 2 Contrasting Cases.

Mammary Paget disease (MPD) comprises 1.45% all male breast cancers, compared with only 0.68% of all female breast cancers. Patients usually present in the fifth and sixth decades of life with ulceration, eczematous changes, discharge, bleeding, itching, and induration of the nipple and areola. Typically, there is a delay in definitive diagnosis and treatment from the onset of symptoms because most patients are initially treated for a rash. At the time of diagnosis, about half of the patients may have palpable breast mass, positive lymph nodes, or both. In this article, we present 2 cases of male MPD representing the extremes of clinical, radiologic, and histopathologic spectrum of the disease. One patient presented with a rash of the nipple of several months duration without an underlying lesion, whereas the other presented with sensitivity and pain of the nipple for 1 year and an underlying mass. Biopsies were diagnostic of MPD in both cases, and definitive surgery revealed an underlying ductal carcinoma in situ in the first case and an invasive ductal carcinoma in the second, highlighting the importance of early biopsy to initiate appropriate management.

A Clinical Feasibility Trial for Identification of Exceptional Responders in Whom Breast Cancer Surgery Can Be Eliminated Following Neoadjuvant Systemic Therapy.

OBJECTIVE: To determine the accuracy of fine-needle aspiration (FNA) and vacuum-assisted core biopsy (VACB) in assessing the presence of residual cancer in the breast after neoadjuvant systemic therapy (NST). SUMMARY BACKGROUND DATA: Pathologic complete response (pCR) rates after NST have improved dramatically, suggesting that surgery might be avoided in some patients. Safe avoidance of surgery would require accurate confirmation of no residual invasive/in situ carcinoma. METHODS: Forty patients with T1-3N0-3 triple-negative or HER2-positive cancer receiving NST were enrolled in this single-center prospective trial. Patients underwent ultrasound-guided or mammography-guided FNA and VACB of the initial breast tumor region before surgery. Findings were compared with findings on pathologic evaluation of surgical specimens to determine the performance of biopsy in predicting residual breast disease after NST. RESULTS: Median initial clinical tumor size was 3.3 cm (range, 1.2-7.0 cm); 16 patients (40%) had biopsy-proven nodal metastases. After NST, median clinical tumor size was 1.1 cm (range, 0-4.2 cm). Nineteen patients (47.5%) had a breast pCR and were concordant with pathologic nodal status in 97.5%. Combined FNA/VACB demonstrated an accuracy of 98% (95% CI, 87%-100%), false-negative rate of 5% (95% CI, 0%-24%), and negative predictive value of 95% (95% CI, 75%-100%) in predicting residual breast cancer. VACB alone was more accurate than FNA alone (P = 0.011). CONCLUSIONS: After NST, image-guided FNA/VACB can accurately identify patients with a breast pCR. Based on these results, a prospective clinical trial has commenced in which breast surgery is omitted in patients with a breast pCR after NST according to image-guided biopsy.

Biopsy Feasibility Trial for Breast Cancer Pathologic Complete Response Detection after Neoadjuvant Chemotherapy: Imaging Assessment and Correlation Endpoints.

PURPOSE: This study was designed to present the secondary imaging endpoints of the trial for evaluating mammogram (MMG), ultrasound (US) and image guided biopsy (IGBx) assessment of pathologic complete response (pCR) in breast cancer (BC) patients undergoing neoadjuvant chemotherapy (NAC). METHODS: Patients with T1-3, N0-3, M0 triple-negative or HER2-positive BC who received NAC were enrolled in an Institutional Review Board-approved prospective, clinical trial. Patients underwent US and MMG at baseline and after NAC. Images were evaluated for residual abnormality and to determine modality for IGBx [US-guided (USG) or stereotactic guided (SG)]. Fine-needle aspiration and 9-G, vacuum-assisted core biopsy (VACBx) of tumor bed was performed after NAC and was compared with histopathology at surgery. RESULTS: Forty patients were enrolled. Median age was 50.5 (range 26-76) years; median baseline tumor size was 2.4 cm (range 0.8-6.3) and 1 cm (range 0-5.5) after NAC. Nineteen patients had pCR: 6 (32%) had residual Ca2+ presurgery, 5 (26%) residual mass, 1 (5%) mass with calcifications, and 7 (37%) no residual imaging abnormality. Sensitivity, specificity, and accuracy of US, MMG, and IGBx for pCR were 47/95/73%, 53/90/73%, and 100/95/98%, respectively. Twenty-five (63%) patients had SGBx and 15 (37%) had US-guided biopsy (USGBx). Median number of cores was higher with SGBx (12, range 6-14) than with USGBx (8, range 4-12), p < 0.002. Positive predictive value for pCR was significantly higher for SG VACBx than for USG VACBx (100 vs. 60%, p < 0.05). CONCLUSIONS: SG VACBx is the preferred IGBx modality for identifying patients with pCR for trials testing the safety of eliminating surgery.

American College of Radiology-Compliant Short Protocol Breast MRI for High-Risk Breast Cancer Screening: A Prospective Feasibility Study.

OBJECTIVE: The purpose of this study was to assess the feasibility of a short protocol for screening breast MRI that is noninferior to standard-of-care (SOC) MRI in image quality that complies with American College of Radiology accreditation requirements. SUBJECTS AND METHODS: In a prospective feasibility trial, 23 women at high risk underwent both an initial SOC MRI examination that included axial iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) and T1-weighted volume imaging for breast assessment (VIBRANT) dynamic contrast-enhanced sequences and a separate short breast MRI protocol comprising a fast spin-echo (FSE) triple-echo Dixon T2 sequence for T2-weighted imaging and a 3D dual-echo fast spoiled gradient-echo two-point Dixon sequence for dynamic contrast-enhanced imaging from October 1, 2015, through May 2, 2016. Image quality assessment was performed by three radiologists, who scored the images for fat saturation, artifact severity, and quality of normal anatomic structures. Enhancing lesions were evaluated according to BI-RADS MRI features. Quantitative analysis was performed by measuring the signal intensity of anatomic areas in each patient. RESULTS: The mean acquisition time for short-protocol breast MRI was 9.42 minutes and for SOC MRI was 22.09 minutes (p < 0.0001). The mean table times were 13.92 and 35.87 minutes (p < 0.0001). Compared with the FSE triple-echo Dixon T2 short-protocol breast MRI sequence, the IDEAL SOC MRI sequence had significantly worse motion artifact (p < 0.01) and fat saturation (p = 0.04). The other parameters did not differ significantly. Quantitative analysis showed that the FSE triple-echo Dixon T2 sequence had more effective fat saturation and higher tissue contrast. All five lesions were given the same assessments by the readers, and at BI-RADS lesion morphologic ranking, identical high image quality scores were assigned to both the VIBRANT and 3D dual-echo fast spoiled gradient-echo 2-point Dixon sequences. CONCLUSION: Short-protocol breast MRI comprising a T2-weighted sequence and a fast dynamic sequence with less than 10-minute acquisition time is feasible and has image quality at least equivalent to that of an SOC MRI protocol with a > 20-minute mean acquisition time. Larger studies comparing the cancer detection rate, sensitivity, and specificity of each imaging protocol are needed to determine whether short-protocol breast MRI can replace SOC MRI to screen patients at high breast cancer risk.

Performance of Mid-Treatment Breast Ultrasound and Axillary Ultrasound in Predicting Response to Neoadjuvant Chemotherapy by Breast Cancer Subtype.

BACKGROUND: The primary objective was to determine whether mid-treatment ultrasound measurements of index breast tumors and index axillary nodes of different cancer subtypes associate with residual cancer burden (RCB). METHODS: Patients with invasive breast cancer who underwent neoadjuvant chemotherapy and had pre-treatment and mid-treatment breast and axillary ultrasound were included in this single-institution, retrospective cohort study. Linear regression analysis assessed associations between RCB with (a) change in index breast tumor size, (b) change in index node size, and (c) absolute number of abnormal nodes at mid-treatment. Multivariate linear regression was used to calculate best-fit models for RCB. RESULTS: One hundred fifty-nine patients (68 triple negative breast cancer [TNBC], 45 hormone receptor [HR]+/human epidermal growth factor receptor 2 [HER2]-, and 46 HR-/HER2+) were included. Median age at diagnosis was 50 years, range 30-76. Median tumor size was 3.4 cm, range 0.9-10.4. Pathological complete response/RCB-I rates were 36.8% (25/68) for TNBC patients, 24.4% (11/45) for HR+/HER2- patients, and 71.7% (33/46) for HR-/HER2+ patients. Linear regression analyses demonstrated associations between percent change in tumor ultrasound measurements at mid-treatment with RCB index score in TNBC and HR+/HER2- (p < .05) but not in HR-/HER2+ (p > .05) tumors and an association between axillary ultrasound assessment of number of abnormal nodes at mid-treatment with RCB index score across all subtypes (p < .05). CONCLUSION: Performance characteristics of breast ultrasound associated with RCB vary by cancer subtype, whereas the performance characteristics of axillary ultrasound associated with RCB are consistent across cancer subtype. Breast and axillary ultrasound may be valuable in monitoring response to neoadjuvant therapy. The Oncologist 2017;22:394-401 IMPLICATIONS FOR PRACTICE: The differential performance characteristics of breast ultrasound by molecular subtype and the consistent performance characteristics of axillary ultrasound across molecular subtypes can have clinical utility in monitoring response to neoadjuvant therapy.

Breast cancer neoplastic seeding in the setting of image-guided needle biopsies of the breast.

PURPOSE: To identify clinicopathologic, technical, and imaging features associated with neoplastic seeding (NS) following image-guided needle breast biopsy. METHODS: We performed an institutional review board-approved retrospective review of patients presenting with a new diagnosis of breast cancer or suspicious breast findings requiring biopsy with subsequent diagnosis of NS. The time from biopsy to NS diagnosis was calculated. Histology, grade, estrogen receptor (ER) status, progesterone receptor (PR) status, HER2 status, T category, and N category were recorded. Biopsy guidance method, needle gauge, and number of passes were reviewed in addition to the mammographic and sonographic features of the primary tumors and the NS. RESULTS: Eight cases of NS were identified in 4010 patients. The mean time from biopsy to NS diagnosis was 60.8 days. The most frequent histology was invasive ductal carcinoma (7/8). Six cases were grade 3 (75.0%). Five primary breast cancers were ER, PR, and HER2 negative (62.5%). Seven patients underwent biopsy with ultrasound guidance. Multiple-insertion, non-coaxial ultrasound-guided core-needle biopsy was done in 6 cases. Mammographic presentation of NS was focal asymmetry (3/7 cases), mass (1/7), calcifications only (1/7), or occult (2/7). Sonographic presentation of NS was most often a mass (7/8) with irregular shape (5/7) and without circumscribed margins (6/7) and was occult in 1 case (1/8). NS distribution was subdermal and intradermal. CONCLUSION: High-grade, triple-negative breast cancers and multiple-insertion, non-coaxial biopsies may be risk factors for NS. NS should be suspected on the basis of the superficial and linear pattern of disease progression in these patients.

Comparison of the accuracy of US-guided biopsy of breast masses performed with 14-gauge, 16-gauge and 18-gauge automated cutting needle biopsy devices, and review of the literature.

OBJECTIVE: To compare the diagnostic accuracy of ultrasound (US)-guided core needle biopsy (CNB) of breast masses performed with 14-gauge, 16-gauge and 18-gauge needles. METHODS: We retrospectively reviewed the charts of 1,112 patients who underwent US-guided breast CNB with 14-gauge, 16-gauge and 18-gauge needles. Cases with surgical excision or a minimum of 2 years of imaging follow-up were included. Rates of sample inadequacy, discordance with surgical or imaging findings and upgrade of DCIS to invasive cancer or high-risk lesion to in situ or invasive cancer were computed for each needle size. RESULTS: The study included 703 CNBs: 203 performed with 14-gauge, 235 with 16-gauge and 265 with 18-gauge needles. There were no significant differences between 14-gauge, 16-gauge and 18-gauge needles in rates of specimen inadequacy (0 %, 0.4 % and 1.9 %, respectively) (p = 0.084); surgical discordance (2.6 %, 2.9 % and 3.8 %) (p = 0.76); imaging discordance (0 %, 0 % and 2 %) (p = 1.0); DCIS upgrade (43 %, 43 % and 36 %) (p = 1.00) or high-risk lesion upgrade (38 %, 25 % and 55 %) (p = 0.49). CONCLUSION: There was no statistically significant difference in diagnostic accuracy of US-guided CNB of breast masses performed with 14-gauge, 16-gauge and 18-gauge needles. KEY POINTS: • Percutaneous image-guided breast core needle biopsy (CNB) is the standard of care. • Breast CNB with 14-gauge, 16-gauge and 18-gauge needles has similar diagnostic accuracy. • Smaller gauge needles can be confidently used for ultrasound-guided breast CNB.

Imaging-Concordant Benign MRI-Guided Vacuum-Assisted Breast Biopsy May Not Warrant MRI Follow-Up.

OBJECTIVE: The follow-up of breast lesions with imaging-concordant benign histopathology results on MRI-guided vacuum-assisted biopsy (VAB) is not currently standardized. We determined the false omission rate of breast MRI-guided VAB with benign histopathology (negative results) to assess whether breast MRI follow-up is needed. MATERIALS AND METHODS: The medical records of patients who underwent 9-gauge breast MRI-guided VAB during 2007-2012 were reviewed retrospectively. Lesions with imaging-concordant benign histopathology results from MRI-guided VAB and surgery or 2 years or more of imaging follow-up were included. The false omission rate (1 - negative predictive value; [number of false-negative results / number of negative results]) of MRI-guided VAB was calculated. RESULTS: One hundred sixty-nine lesions were included, and 135 had only imaging follow-up (mammography follow-up: range, 17-107 months [median, 52 months]; MRI follow-up: range, 5-95 months [median, 35 months]). Of the 135 lesions with only imaging follow-up, 48 had mammography only (range, 26-86 months; median, 52 months), and 87 had mammography (range, 17-107 months; median, 52 months) and MRI (range, 5-95 months; median, 35 months). Thirty-four lesions had surgical correlation, and there were no cases of imaging-surgical discordance. Four malignancies were later diagnosed in the same breast in which MRI-guided VAB had been performed. One (0.6%) malignancy was invasive ductal carcinoma at 1 cm from the MRI-guided VAB site; it was mammographically detected 24 months after MRI-guided VAB. The other three malignancies developed 4 cm or more from the site of MRI-guided VAB: one ductal carcinoma in situ (DCIS) detected on mammography 12 months after MRI-guided VAB, one DCIS detected on MRI 24 months after MRI-guided VAB, and one Paget disease lesion detected at physical examination 32 months after MRI-guided VAB. CONCLUSION: Breast MRI-guided VAB has a low false omission rate. MRI follow-up of lesions with concordant benign MRI-guided VAB histopathology results may not be warranted.

Radiologic Mapping for Targeted Axillary Dissection: Needle Biopsy to Excision.

OBJECTIVE: The purpose of this article is to describe the feasibility and safety of a multidisciplinary approach to imaging-guided axillary staging that facilitates personalized, less invasive surgical management of the axilla through targeted axillary dissection in patients with biopsy-proven nodal metastasis undergoing neoadjuvant chemotherapy. CONCLUSION: Axillary nodal status, critical in breast cancer staging, affects prognosis and treatment. As the paradigm shifts toward minimally invasive therapy, a clip marker is placed in the biopsied metastatic node for patients with N1-N2 disease undergoing neoadjuvant chemotherapy to facilitate targeted axillary dissection of the clipped node. This node is typically localized with a radioactive seed at sentinel lymph node dissection to determine whether further axillary surgery is warranted.

Phase 2 study of neoadjuvant enzalutamide and paclitaxel for luminal androgen receptor-enriched TNBC: Trial results and insights into "ARness".

Luminal androgen receptor (LAR)-enriched triple-negative breast cancer (TNBC) is a distinct subtype. The efficacy of AR inhibitors and the relevant biomarkers in neoadjuvant therapy (NAT) are yet to be determined. We tested the combination of the AR inhibitor enzalutamide (120 mg daily by mouth) and paclitaxel (80 mg/m2 weekly intravenously) (ZT) for 12 weeks as NAT for LAR-enriched TNBC. Eligibility criteria included a percentage of cells expressing nuclear AR by immunohistochemistry (iAR) of at least 10% and a reduction in sonographic volume of less than 70% after four cycles of doxorubicin and cyclophosphamide. Twenty-four patients were enrolled. Ten achieved a pathologic complete response or residual cancer burden-I. ZT was safe, with no unexpected side effects. An iAR of at least 70% had a positive predictive value of 0.92 and a negative predictive value of 0.97 in predicting LAR-enriched TNBC according to RNA-based assays. Our data support future trials of AR blockade in early-stage LAR-enriched TNBC.