Stereotactic Core Biopsy Research Articles

Use of Real Time Specimen Radiography to Evaluate the Number of Stereotactic Core Biopsy Specimens Containing Calcifications Required for Diagnosis.

To determine the minimum number of stereotactic biopsy specimens containing calcifications sufficient for pathologic diagnosis and the minimum number of specimens containing calcifications sufficient for immunohistochemistry (IHC) in cases of malignancy. In this IRB-exempt quality assurance initiative, individual specimens from 126 patients with 129 calcified targets retrieved using a stereotactic system with real time specimen imaging were prospectively analyzed. Pathology was reported independently for each specimen containing calcifications. In every case, the pathologist reported which specimen containing calcifications was sufficient for diagnosis and, in cases of malignancy, which calcified specimen was sufficient for diagnosis and IHC. A diagnosis was made from the first calcified specimen in 74% of cases (95/129), from the first two calcified specimens in 92% (119/129) of cases, and from the first three calcified specimens in 100% of cases. Pathology was benign in 66% (85/129) of cases, with the diagnosis made from the first calcified specimen in 78% (66/85) of cases. High-risk lesions were the primary pathology in 8% (11/129) of cases, with 55% (6/11) diagnosed from the first calcified specimen. Pathology was malignant in 26% (33/129) of cases. The first calcified specimen was sufficient for diagnosis and IHC in 73% (24/33) of malignancies and the first three calcified specimens were sufficient for diagnosis and IHC in all cases of malignancy. Three cores verified to contain calcifications on real time specimen imaging were sufficient to make a diagnosis in all cases and to make a diagnosis and obtain IHC in nearly all cases of malignancy.

AN UNUSUAL LARGE SIZE DUCTAL CARCINOMA IN SITU IN A PATIENT ON LITHIUM THERAPY: A CASE REPORT WITH LITERATURE REVIEW

Ductal carcinoma in situ (DCIS) is the earliest and most curable form of breast cancer. Patients who harbour this disease for quite some time usually have micro invasion by virtue of high-grade disease or big size. Herein, we report a case of 56-year-old postmenopausal woman presenting with a one-year history of blood-stained nipple discharge from right breast. She was a known case of depression receiving oral anti-depressants containing lithium for 20 years. Her mammogram was performed followed by ultrasound breast. Mammogram identified suspicious clusters of micro calcifications hence subjected to stereotactic core biopsy which revealed two separate foci of high-grade DCIS. Therefore, based on her clinical, radiological, and pathological findings she was subjected to mastectomy and sentinel node biopsy. Final histopathology showed big DCIS (10×8×3 cm in size) with immunohistochemical stains confirmed no invasive focus on extensive sampling. Therefore, we postulated that it might be correlated to the use of Lithium which has anti-cancer properties.

Abstract P4-03-02: Comparison of non-invasive and invasive methods for evaluating pathologic response in patients with triple negative and HER2-positive breast cancer after neoadjuvant systemic therapy

Abstract Goals: The main goal was to compare the informativity of breast imaging techniques (ultrasound with sonoelastography, mammography, SPECT-CT) with stereotactic 12-point tumor bed core biopsy after neoadjuvant therapy and prior to surgical excision of the residual tumor. Materials and methods: The study was conducted at the Department of Breast Tumors, N.N. Petrov National Research Center of Oncology. Since February 2018, we have included 60 patients with TNBC and HER2-positive ER+/ ER- breast cancer with cT1-4N1-3M0. Neoadjuvant TNBC group received 6 cycles of paclitaxel 175 mg / m2 + doxorubicin 50 mg / m2 + carboplatin AUC5 1p/21 day. The HER2+ group received 4 cycles of followed by 4 cycles of docetaxel with trastuzumab q21d. The response to neoadjuvant treatment was assessed in all patients using standard two-dimensional mammography, ultrasound elastography, and SPECT-CT. The 12-point tumor bed core biopsy was performed in the operating room using previously marked tumor projections. Results: The pathology response rates in the TNBC group (n = 30) were: pCR = 70% / RD = 30%, the preoperative core biopsy showed high rates of precision (Acc. = 90%, Sens. = 100%, Spec. = 67% with pCR and 100% at RD, PPV = 88% at pCR and 100% at RD, NPV = 100% at pCR and 88% at RD), non-invasive imaging techniques in total were less informative (Acc. = 62%, Sens. = 48% with pCR and 33% with RD, Spec. = 96% with pCR and 48% with RD, PPV = 97% with pCR and 46 % at RD, NPV = 46% at pCR and 97% at RD). In the HER2-positive group (n = 30), the response rates were was: pCR = 67% / RD = 33%, we received the following data on preoperative core biopsy showed (Acc. = 93%, Sens. = 100%, Spec. = 80% at pCR and 100% at RD, PPV = 91% at pCR and 100% at RD, NPV = 100% at pCR and 91% at RD), non-invasive breast imaging techniques in total also showed less information (Acc. = 48%, Sens. = 28% with pCR and 41% with RD, Spec. = 87% with pCR and 28% with RD, PPV = 86% with pCR and 38% at RD, NPV = 38% at pCR and 86% at RD). Conclusion: Comparison of the contemporary breast imaging techniques and 12-point stereotactic core biopsy of a tumor bed with standard pathology assessment showed higher positive predictive value and overall superiority of the core biopsy. Citation Format: Petr Krivorotko, Sergey Yerechshenko, E. Zhiltsova, G. Dashyan, A. Bessonov, T. Tabagua, K. Zernov, O. Ivanova, L. Gigolaeva, K. Nikolaev, A. Komyahov, A. Emelyanov, R. Pesotskiy, T. Semiglazova, V.F. Semiglazov. Comparison of non-invasive and invasive methods for evaluating pathologic response in patients with triple negative and HER2-positive breast cancer after neoadjuvant systemic therapy [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-03-02.

Abstract PD9-03: A combination of intra- and peri-lesional deep learning classifiers from multiple views enables accurate diagnosis of architectural distortion malignancy with digital breast tomosynthesis

Abstract Background: 3D digital breast tomosynthesis (DBT) offers greater sensitivity than 2D mammography to the presence of architectural distortions (AD), a suspicious finding requiring biopsy. This higher sensitivity to AD is only beneficial if DBT can differentiate benign AD, such as radial scars (RS) from malignant AD (MAD). Automated analysis of clinical images using a neural network has potential to enhance the accuracy of breast cancer diagnosis, but such applications focus on screening and currently struggle with more challenging diagnoses (e.g. MAD vs. RS) where computer assistance would provide great clinical utility. In this work, we define a deep learning (DL) framework utilizing amalgamate predictions from a group of neural networks, specialized for multiple lesion regions and different acquisitional views to distinguish MAD from RS. Methods: A retrospective analysis was conducted of 69 patients screened at a single institution, each with AD visible on one or more DBT views. Stereotactic core biopsy determined 42 AD to be MAD and the remaining 27 to be RS. An attending breast radiologist manually identified a circular region of interest (ROI) containing the AD on a single slice of the mediolateral (ML, n=72) and/or craniocaudal (CC, n=68) views. 56 patients were utilized for training and tuning the DL networks in cross-validation, while 25 volumes from 13 patients (8 MAD, 5 RS) were held for independent testing. Volumetric samples of size 24x24x12 pixels were extracted randomly within each ROI for input to the networks. Two neural networks were trained to separately recognize patterns of MAD at the intra- and peri-lesional region. Pairs of networks were trained separately for analysis of the CC and the MLO view, resulting in 4 possible network variations. These networks were first assessed individually by cross-validation in the training set, then predictions from each were combined for diagnosis in the independent testing set. Performance was assessed by area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy. Results: All networks individually achieved strong performance in distinguishing RS from MAD when assessed via cross-validation in the training set. On the independent test set, networks trained to recognize patterns of malignancy at the center of the distortion outperformed those focused on the lesion margin. The CC view was found to be most discriminating in neural network assessment. Independent Test PerformanceNetwork TypeAUCSensitivitySpecificityIntralesional, CC0.650.800.50Perilesional, CC0.510.400.63Intralesional, ML0.490.600.38Perilesional, ML0.550.600.50Combined Performance0.800.601.0 When predictions from these networks were combined for diagnosis on the independent validation set, performance increased significantly to an AUC of 0.8, with a sensitivity of 0.6 and a specificity of 1.0. Conclusions: In this investigation, we demonstrated that specialized deep learning classifiers, created to address the diagnosis of MAD vs RS, can assist in diagnostic settings without generating false negatives. Our approach combines neural networks to make a diagnosis based on various spatial regions from multiple DBT views. Our approach demonstrated very high specificity which may reduce the number of benign RS biopsies and surgical excisions for AD detected by DBT. Future work will further validate these findings on a larger, multi-institutional cohort and explore their influence on clinical decision-making. Citation Format: Tristan Maidment, Nathaniel Braman, Yijiang Chen, Farhad Mehrkhani, Uliyana Yankevich, Donna Plecha, Anant Madabhushi. A combination of intra- and peri-lesional deep learning classifiers from multiple views enables accurate diagnosis of architectural distortion malignancy with digital breast tomosynthesis [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD9-03.

Statistical multiscale mapping of IDH1, MGMT, and microvascular proliferation in human brain tumors from multiparametric MR and spatially-registered core biopsy

We propose a statistical multiscale mapping approach to identify microscopic and molecular heterogeneity across a tumor microenvironment using multiparametric MR (mp-MR). Twenty-nine patients underwent pre-surgical mp-MR followed by MR-guided stereotactic core biopsy. The locations of the biopsy cores were identified in the pre-surgical images using stereotactic bitmaps acquired during surgery. Feature matrices mapped the multiparametric voxel values in the vicinity of the biopsy cores to the pathologic outcome variables for each patient and logistic regression tested the individual and collective predictive power of the MR contrasts. A non-parametric weighted k-nearest neighbor classifier evaluated the feature matrices in a leave-one-out cross validation design across patients. Resulting class membership probabilities were converted to chi-square statistics to develop full-brain parametric maps, implementing Gaussian random field theory to estimate inter-voxel dependencies. Corrections for family-wise error rates were performed using Benjamini-Hochberg and random field theory, and the resulting accuracies were compared. The combination of all five image contrasts correlated with outcome (P < 10−4) for all four microscopic variables. The probabilistic mapping method using Benjamini-Hochberg generated statistically significant results (α ≤ 0.05) for three of the four dependent variables: (1) IDH1, (2) MGMT, and (3) microvascular proliferation, with an average classification accuracy of 0.984 ± 0.02 and an average classification sensitivity of 1.567% ± 0.967. The images corrected by random field theory demonstrated improved classification accuracy (0.989 ± 0.008) and classification sensitivity (5.967% ± 2.857) compared with Benjamini-Hochberg. Microscopic and molecular tumor properties can be assessed with statistical confidence across the brain from minimally-invasive, mp-MR.

Diagnostic accuracy of the Videssa protein-based liquid biopsy for breast cancer in suspicious mammography.

e13034 Background: The Videssa protein-based blood test (Provista Diagnostics) is a combined proteomic biomarker assay that aims to detect established breast cancer – rendering it useful in patients with abnormal or difficult-to-interpret mammograms. Since the incidence of malignancy for BI-RADS 4 biopsies is approximately 20%, a significant percentage of patients undergo needle biopsy unnecessarily. The Videssa assay provides an alternative diagnostic method by way of a non-invasive liquid biopsy. Methods: Our goal was to assess whether this liquid biopsy combined with 3D tomographraphic mammography could accurately predict disease status to reduce the amount of unnecessary tissue biopsies. An IRB-approved, prospective, single-arm study had patients with BI-RADS4 lesions with calcifications requiring tissue biopsy undergo the blood test prior to stereotactic core biopsy. Subsequent results and biopsy pathology were correlated. Results: 46 patients were initially entered with BI-RADS4 calcifications. 9 patients had DCIS (19.6%) and 37 patients had benign calcifications (80.4%). No patient had invasive cancer. Liquid biopsy results were elevated in 2 patients with DCIS (22% sensitivity) and in 5 patients with benign biopsies (10.8%). At interim analysis, the liquid biopsy demonstrated a 28.5% positive predictive value (PPV) and 82% negative predictive value (NPV). Tumor grade did not affect results. We subsequently discontinued using the blood test for BI-RADS4 calcifications and enrolled 13 patients with non-palpable solid lesions to determine the correlation. The liquid biopsy was elevated in 1 of 4 patients with invasive cancer (25% sensitivity) and was not elevated in all 9 patients with benign biopsies (100% NPV). At one-year follow-up, 3 of the 5 patients with an elevated blood assay and negative biopsy have had no incidence of cancer on subsequent imaging. The remaining 2 patients are scheduled for follow-up. Conclusions: In our study, the NPV of the Videssa liquid biopsy is not robust enough to defer tissue biopsy in any patient with indeterminate calcifications on imaging, nor is it specific enough to help predict results in high risk solid lesions. We do not see this liquid biopsy changing our current practice.

EVALUATION OF CLUSTERED MICROCALCIFICATIONS, INITIALLY GRADED AS LIKELY MALIGNANT ON BASELINE MAMMOGRAPHY, WITH STEREOTACTIC BIOPSY: A RAD-PATH CORRELATION

Background: Stereotactic-guided breast biopsy is an invincible tool to sample abnormalities visible only on mammography with subtle or occult ultrasound findings. Common mammographic abnormalities which require stereotactic core biopsy include calcifications, architectural distortion and satellite lesions. With advancement in techniques for adequate localisation of lesions, the use of stereotactic needle breast biopsy is exponentially increasing. A study was performed to look for frequency of benignancy or malignancy of microcalcifications and architectural distortions in patients initially falling in malignant category of Breast Imaging-Reporting and Data System of American College of Radiology (BI-RADS®) Assessment Categories.Materials and Methods: Patient presenting in outpatient (OPD) clinic who underwent stereotactic biopsies for labelled malignant on mammograms from May 2015 to May 2018 was included in retrospective study. Age, technique used, baseline mammogram and histopathology were reviewed.Results: A total of 91 patients underwent stereotactic biopsy. Age range varied between 28 and 81 years. Stereotacticguided biopsies were taken using a standard 14-gauge core needle with long throw of 22 mm excursion. None of the biopsy was inconclusive. In comparison with baseline mammograms and histopathology, 40% of the clusters of microcalcification which were initially labelled as malignant turned out to be malignant on histopathology as well, whereas 60% were reported as benign breast parenchyma.Conclusion: Agreement between the diagnostic accuracy of microcalcifications on mammogram and histopathology of same lesions after stereotactic biopsy was comparable to international figures with probability of being benign surpassing malignant on routine screening.Key words: Breast cancer, mammography, microcalcifications, stereotactic biopsy

Abstract P4-02-05: Diagnostic value of breast MRI in evaluating total extent of disease when non-calcified DCIS is present in stereotactic core biopsy samples

Abstract PURPOSE To compare the extent of disease as seen on mammography, breast MRI and final surgical pathology in all patients with non-calcified DCIS identified on stereotactic core biopsy. Can MRI provide useful diagnostic information to the surgeon when mammographically occult DCIS is present. METHOD AND MATERIALS All patients with stereotactic core biopsies performed at the University of Chicago from 2010 to 2017 were retrospectively reviewed. Patients with pathology demonstrating DCIS in non-calcified cores on stereotactic biopsy were further selected based on whether they had a subsequent breast MRI and definitive surgical treatment. A total of 76 patients met these criteria. All patients undergoing stereotactic core biopsy had at least six 9-gauge cores removed, all of which were radiographed and separated based on whether calcifications were present or absent. Select patients with documented DCIS in the non-calcified cores had a MRI. All patients with MRI underwent a routine diagnostic protocol consisting of one pre- and five post-contrast bilateral, fat suppressed T1 sequences along with a non-fat suppressed T2 sequence. Final surgical treatment was subsequently determined and performed by the breast surgeon. RESULTS 76 women met all criteria for this study. In 16/76 (21%) of the cases, MRI revealed greater extent of disease than was detected via mammography, and led to change in management in half of those cases (8/76 - 11%). In all 16 of these cases, final surgical pathology confirmed the MRI-detected extent of disease. In 52/76 (68%) of the cases, MRI confirmed the extent of disease detected on mammography and final surgical pathology. In 8/76 (11%) of the cases, MRI showed little to no abnormal enhancement at site of mammographically detected calcifications, even though final surgical pathology confirmed presence of residual disease. CONCLUSION The presence of non-calcified DCIS in stereotactic core biopsy samples raises the suspicion for the presence of mammographically occult disease. Breast MRI performed in this setting shows that in majority (82% -68/76) of the cases, MRI can either confirm or even advantageously reveal greater extent of disease than was initially detected on mammography. Furthermore, there can be a change in management due to the breast MRI findings. CLINICAL RELEVANCE/APPLICATION Breast MRI can be a useful diagnostic tool for the surgeon when non-calcified DCIS is present in stereotactic core biopsy samples. Citation Format: Sheth D, Bao J, Abe H, Jaskowiak N. Diagnostic value of breast MRI in evaluating total extent of disease when non-calcified DCIS is present in stereotactic core biopsy samples [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-02-05.

Post–Vacuum-Assisted Stereotactic Core Biopsy Clip Displacement: A Comparison Between Commercially Available Clips and Surgical Clip

PurposeThe placement of localization clips following percutaneous biopsy is a standard practice for a variety of situations. Subsequent clip displacement creates challenges for imaging surveillance and surgical planning, and may cause confusion amongst radiologists and between surgeons and radiologists. Many causes have been attributed for this phenomenon including the commonly accepted “accordion effect.” Herein, we investigate the performance of a low cost surgical clip system against 4 commercially available clips. MethodsWe retrospectively reviewed 2112 patients who underwent stereotactic vacuum-assisted core biopsy followed by clip placement between January 2013 and June 2016. The primary performance parameter compared was displacement >10 mm following vacuum-assisted stereotactic core biopsy. Within the group of clips that had displaced, the magnitude of displacement was compared. ResultsThere was a significant difference in displacement among the clip types (P < .0001) with significant pairwise comparisons between pediatric surgical clips and SecureMark (38% vs 28%; P = .001) and SenoMark (38% vs 27%; P = .0001) in the proportion displaced. The surgical clips showed a significant magnitude of displacement of approximately 25% greater average distance displaced. ConclusionsAs a whole, the commercial clips performed better than the surgical clip after stereotactic vacuum-assisted core biopsy suggesting the surrounding outer component acts to anchor the central clip and minimizes clip displacement. The same should apply to tomosynthesis-guided biopsy.

Stereotactic Core Biopsy Following Screening Mammography: A Danish Retrospective National Cohort Study

Background: Since introducing stereotactic core biopsy (SCB) on breast lesions in Denmark, no national follow-up of the procedure has been executed. Purpose: To evaluate performance of SCB in Danish mammography screening. 3 areas were selected for evaluation: diagnostic value of SCB, performance of the Danish 7-tier mamma-radiological classifications system, DKBI-RADS, and diagnostic delay for SCB-diagnosis. Materials & Methods: Danish retrospective national cohort study including 2195 screening patients undergoing SCB. Study period: 01.01.2010 to 30.09.2012. Patients were identified from The Danish National Patient Register. Pathology-data were obtained from the Danish Pathology Database. Radiological-data according to DKBI-RADS were recorded. Diagnostic delay from clinical mammography until diagnosis was registered. Results: 173 SCBs indicated cancer; all operated with 3 cases finalized as benign. 1296 cases were determined benign with diagnostic surgery in 81 cases of which 31 were concluded pre-malignant/malignant. Correlation between DKBI-RADS and pathology diagnosis: 329 of 485 DKBI-RADS3, 227 of 450 DKBI-RADS4 were benign. 4 of 16 DKBI-RADS5 were benign. The diagnostic value of pre-malignant/malignant SCB related to results from surgery showed 94.4% sensitivity and a positive predictive value of 93.9%. Median diagnostic-time of single-biopsy was 13 days. Conclusion: The performance of SCB in Denmark is comparable to international studies regarding the diagnostic value of malignant SCB. The study indicates that DKBI-RADS classifications are not used consistently regarding micro-calcifications selected in screening-mammographies. Diagnostic delay is acceptable, subject to EUSOMA specifications, regarding single-biopsy.

Breast MRI as a Problem-solving Study in the Evaluation of BI-RADS Categories 3 and 4 Microcalcifications: Is it Worth Performing?

We aimed to investigate the utility of problem-solving breast magnetic resonance imaging (MRI) for mammographic Breast Imaging Reporting and Data System (BI-RADS) categories 3 and 4 microcalcifications. Between January 1, 2010 and December 31, 2011, 138 women with 146 areas of categories 3 and 4 microcalcifications without sonographic correlates underwent breast MRI and had a stereotactic core biopsy using an 11-gauge needle or follow-up at least for 24 months. Positive predictive value (PPV), negative predictive value, sensitivity, and specificity were calculated on the basis of BI-RADS category, with categories 1-3 being considered benign and categories 4 and 5 being considered malignant. Twenty-four cases (16.4%) were malignant (18 ductal carcinoma in situ, 6 invasive). MRI increased PPV and specificity from 43% to 68% and from 80% to 93% (P = .054 and .005) compared to mammography. Within 102 category 3 microcalcifications, 5 carcinomas were assessed correctly as category 4 by MRI. Within 44 category 4 microcalcifications, a correct diagnosis was made by MRI in 77% (34 of 44) as opposed to 43% (19 of 44) by mammography, and 80% (20 of 25) of unnecessary biopsies could have been avoided. Within the 24 carcinomas, 5 were negative at MRI. MRI-negative carcinomas have a significantly higher possibility of being low grade (ductal carcinoma in situ or invasive) (P = .0362). Breast MRI has the potential to improve the diagnosis of category 3 or 4 microcalcifications and could alter indications for biopsy. Breast MRI could help predict the presence or absence of higher-grade carcinoma for category 3 or 4 microcalcifications.

Video-Based Teaching of Image-Guided Breast Interventions: Stereotactic Core Biopsy Using a Prone Table.

The introduction of new technologies and teaching strategies to educate the digital learner creates the potential for a better and more standardized training experience across programs. Thus, we sought to create an instructional video on stereotactic core breast biopsy that simulates best practices and could be readily accessed by training programs to improve and standardize resident education. At our institution, we use the video and questions as part of a flipped classroom educational activity. Residents are requested to complete the questions at home and watch the video. They then take the posttest questions during the lecture period, at which time the answers are reviewed and there is additional discussion of the procedure. The tests contain both video-related questions and control questions. After viewing the video, there was a 30% mean improvement in the video-related questions compared to a 0% improvement in the control set of questions. An instructional video on stereotactic core biopsy was created with associated assessment questions that can be used at any institution for the purposes of improving and standardizing training in breast imaging procedures. This resource can be especially useful for programs where trainees have limited procedure exposure.

Abstract P3-01-03: Milky Way sign: A potential predictive sign of breast cancer on digital breast tomosynthesis

Abstract Purpose: “Milky Way sign (MWS)”, which we recently reported1), is a new finding on digital breast tomosynthesis (DBT) showing microcalcifications overlying non-calcified band-like density. Our study purpose was to describe frequencies of and imaging findings associated with MWS, and to examine the predictive value of MWS for breast cancer. Materials and Methods: We reviewed all stereotactic core biopsies of suspicious calcifications at our institution from 1/1/2015 to 12/31/2015, finding 124 lesions with calcifications, including 20 malignancies (2 IDC, 5 IDC+DCIS, 13 DCIS) and 104 non-malignant lesions (23 high-risk [14 ADH, 6 LCIS/ALH, 1 intraductal papilloma, 2 other atypical], 81 benign), in 116 patients undergoing both 2D mammogram and DBT before biopsies. 2 radiologists reviewed images for the presence of MWS, local breast density within 1 cm surrounding the calcifications, classifying BI-RADS calcification morphology and distribution. We assessed the predictive value of MWS for malignancy using Chi square test and multivariate logistic analysis. Results: MWS was identified more frequently with DBT (27/124, 22%) than with 2D (13/124, 10%), and more in locally less dense tissue than in locally dense tissue. The calcifications in MWS were fine pleomorphic (13/27, 48%), amorphous (8/27, 30%), fine linear/branching (5/27, 19%), or other (1/27, 4%), with distributions of grouped (20/27, 74%), linear (5/27, 19%) or segmental (2/27, 7%) categories. MWS on DBT was observed in 60% (12/20, including 2 IDC, 2 IDC+DCIS, 8 DCIS) of malignant lesions and 14% (15/104) of benign lesions (table1), and was significantly and positively associated with malignant lesions (p &amp;lt; .001). Multivariate analysis demonstrated the MWS on DBT (p &amp;lt; .001) and fine linear/branching calcifications (p &amp;lt; .001) were independent predictors for malignancy. Frequencies of MWS on DBT according to histopathology nMWS positiveMWS negativeMalignancy2012 (60)8 (40)-IDC22 (100)0 (0)-IDC+DCIS52 (40)3 (60)-DCIS138 (62)5 (38)Non-malignant lesion10415 (14)89 (86)-ADH143 (21)11 (79)-LCIS/ALH60 (0)6 (100)-Intraductal papilloma10 (0)1 (100)-Other high-risk20 (0)2 (100)-Benign8112 (15)69 (85)Total12427 (22)97 (78)Data are shown as number with percentage in parenthesis. Conclusions: Although sample size was limited, our results indicate that DBT may contribute in detecting MWS, and that MWS may be a predictive sign for breast cancers, leading to biopsy of suspicious calcifications. Reference 1) Xu Y, Miyake KK, Liu YI, Downey JR, Lipson J, Allison K, Ikeda DM. “The Milky Way Sign: a new diagnostic findings of ductal carcinoma on digital tomosynthesis.” The Breast Journal. 2016 May; 22 (3):349-51. Citation Format: Miyake KK, Lipson JA, Allison KH, Xu Y, Liu YI, Downey JR, Ikeda DM. Milky Way sign: A potential predictive sign of breast cancer on digital breast tomosynthesis [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-01-03.

Rapid and fulminant leptomeningeal spread following radiotherapy in diffuse intrinsic pontine glioma

A 4-year-old male presented with rapid-onset cranial nerve palsy and ataxia. Brain magnetic resonance imaging (MRI) revealed a pontine mass lesion with discordant conventional and advanced imaging. A stereotactic core biopsy revealed glioblastoma with immunostaining suggestive of histone H3K27M and TP53 mutation, consistent with diffuse intrinsic pontine glioma. MRI 3 months after radiotherapy revealed extensive new leptomeningeal metastatic disease involving both the supra- and infratentorial brain, as well as the imaged portion of the spine. Tissue procured at the time of needle biopsy has undergone striking in vivo expansion as an orthotopic xenograft.

Abstract P6-02-11: When needles are needed

Abstract Background Women with positive screening mammograms but negative at assessment (false-positive) are referred back to routine screening assuming that they have an average risk of breast cancer. However in a long-term follow-up of women with false-positive screening mammography we found that these women had in fact an excess risk of breast cancer later in life; RR=1.67(von Euler-Chelpin et al, JNCI 2012). This finding has later been supported by Castells et al.(Cancer Epidemiol, 2013). Furthermore, we studied the breast cancer cases in false-positive women and found that 26% of the cases were misclassified and were in fact true positives. However, even correction for misclassification, the false-positive women in our study remained at an excess breast cancer risk. At the same time, it was clear that, in the later periods of our study, when more modern techniques were used, the rate of misclassification decreased (von Euler-Chelpin et al, Cancer Epidemiol., 2014). Over time there have been changes both in the imaging and biopsy techniques. We used data from an organised screening programme in Denmark. Since its start in 1991, needle biopsies have been performed on all palpable solid lesions and on all uncertain, suspicious or malignant findings. In the very beginning fine needle aspiration cytology (FNAC) was used, later to be replaced by needle core biopsies in the majority of cases. Since 2002, suspicious micro-calcifications and impalpable mammographic findings not found by ultrasound have been examined using stereotactic needle core biopsy and later with vacuum-assisted breast biopsy as a replacement for surgical biopsy. To have a needle breast biopsy taken is a psychological burden on the woman. To minimize the harms and maximize the benefits is at the core of developing medical care. We therefore mapped the use of needle biopsies over time in a long-standing, organised screening programme. Method: We used data from the population-based screening mammography program in Copenhagen, Denmark. The programme has a database including personal records on demographic data, date of invitation, data of screening, and test results,1998-2013. Data from the Mammography Register were linked to the Danish Pathology Register (for biopsy procedures). Results: A total of 208 500 screens were included in the study. The rate of recall for assessment ranged between 1.7-3.2% of screened women with a mean of 2.4. The false-positive rate ranged between 1.0-2.5% with a mean of 1.6%. In 1998, 56% of all recalled women had a biopsy taken, which by 2013 had risen to 74% (using two-year smoothing). In proportion of all screens, the biopsy rate was 1.9% in 1998/99 which then fell to 0.7% in 2005/06 and the rose again 2.0% in 2012/13. In 1998, 59% of the biopsies were fine-needle aspiration cytology (FNAC) which by 2013 was only used in 11% of the cases, and replaced by core biopsies, ultrasound or stereotactic guided. Conclusion While the recall rate, as well as the false-positive rate, has been fairly stable during the study period the use of needle core biopsies has had a u-shaped development and has intensified in the later years. Citation Format: von Euler-Chelpin M, Vejborg I, Lænkholm A-V, Guleria S, Peterkin A, Lynge E. When needles are needed. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-02-11.

Abstract P4-01-01: A case series of the Milky Way sign: A diagnostic finding of ductal carcinoma in situ (DCIS) and invasive breast carcinoma (IDC) on digital breast tomosynthesis (DBT)

Abstract Purpose: we have previously described the "Milky Way Sign", which manifests as microcalcifications overlying noncalcified band-like density, best seen in digital breast tomosynthesis (DBT), in a patient with ductal carcinoma in situ (DCIS). Here, we describe a series of patients with DCIS, IDC, and rarely, Atypical Ductal Hyperplasia (ADH) with this sign. Materials and Methods: we performed a systemic search of all stereotactic core biopsies for suspicious calcifications performed at our institution from April 15, 2014, when we first implemented DBT with synthesized 2D mammogram, to October 2, 2014, and identified all cases that were diagnosed as DCIS, IDC, or high-risk lesions (such as ADH, atypical lobular hyperplasia (ALH), and intraductal papilloma) on pathology. From 89 biopsied performed in 87 patients, a total of 13 cases of DCIS, IDC, or IDC with DCIS were identified in 12 patients. 17 cases of high-risk lesions were identified in 16 patients, including 10 ADH in 9 patients, 4 ALH, two intraductal papillomas, and one atypical columnar cell change. Results: Among the 30 cases of suspicious calcifications with a diagnosis of DCIS, IDC, or high-risk lesions, 37% demonstrated the Milky Way Sign (11/30), including 71% of DCIS cases (5/7), 60% of cases of IDC (3/5), 100% of DCIS/IDC (1/1), and 12% of high-risk lesions (2/17). Both high-risk lesions with the Milky Way sign were ADH from the same patient. Among the 11 cases with the Milky Way sign, the breast density at the site of calcifications is either scattered (6/11) or heterogeneously dense (5/11), whereas the density at 1 cm surrounding the calcifications is either fatty (8/11) or scattered (3/11). The breast is less dense surrounding the calcifications in all but one case. The calcifications seen in the Milky Way cases are predominantly fine pleomorphic calcifications except one case of fine linear and linear branching calcifications. The calcifications are grouped (6/11), linear (3/11), or segmental (2/11) in distribution. Five patients also had contrast-enhanced breast MRIs. Among them, three (one each with the diagnosis of DCIS, IDC or DCIS/IDC) had non-mass enhancement on breast MRI that correlated to the Milky Way sign seen on mammogram. The other two patients (one with DCIS and one with IDC) had post biopsy change instead of Non-mass enhancement were seen in the corresponding areas. Conclusion: The Milky Way sign, in the context of DBT, is a novel diagnostic sign for both DCIS and IDC. It may occasionally be seen in ADH cases as well. Features that often associate with the Milky Way sign include less dense tissue surrounding the calcifications, calcifications that are fine pleomorphic in morphology and grouped or linear in distribution. Preliminary results also suggest that the Milky Way sign may correspond to non-mass enhancement seen on contrast-enhanced breast MRI. Clinical Relevance Statement: We hope that the Milky Way sign will facilitate detection of both DCIS and IDC in the context of DBT. Citation Format: Allison K, Xu Y, Liu YI, Miyake KK, Downey JR, Lipson JA, Ikeda DM. A case series of the Milky Way sign: A diagnostic finding of ductal carcinoma in situ (DCIS) and invasive breast carcinoma (IDC) on digital breast tomosynthesis (DBT). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-01-01.

Surgical biopsy is still necessary for BI-RADS 4 calcifications found on digital mammography that are technically too faint for stereotactic core biopsy.

The purpose of this study was to evaluate the outcome of faint BI-RADS 4 calcifications detected with digital mammography that were not amenable to stereotactic core biopsy due to suboptimal visualization. Following Institutional Review Board approval, a HIPAA compliant retrospective search identified 665 wire-localized surgical excisions of calcifications in 606 patients between 2007 and 2010. We included all patients that had surgical excision for initial diagnostic biopsy due to poor calcification visualization, whose current imaging was entirely digital and performed at our institution and who did not have a diagnosis of breast cancer within the prior 2 years. The final study population consisted of 20 wire-localized surgical biopsies in 19 patients performed instead of stereotactic core biopsy due to poor visibility of faint calcifications. Of the 20 biopsies, 4 (20% confidence intervals 2, 38%) were malignant, 5 (25%) showed atypia and 11 (55%) were benign. Of the malignant cases, two were invasive ductal carcinoma (2 and 1.5 mm), one was intermediate grade DCIS and one was low-grade DCIS. Malignant calcifications ranged from 3 to 12 mm. The breast density was scattered in 6/19 (32%), heterogeneously dense in 11/19 (58%) and extremely dense in 2/19 (10%). Digital mammography-detected faint calcifications that were not amenable to stereotactic biopsy due to suboptimal visualization had a risk of malignancy of 20%. While infrequent, these calcifications should continue to be considered suspicious and surgical biopsy recommended.

Diagnostic Accuracy of PET/CT-Guided Percutaneous Biopsies for Malignant Peripheral Nerve Sheath Tumors in Neurofibromatosis Type 1 Patients.

BackgroundMalignant peripheral nerve sheath tumors (MPNST) are one of the most frequent causes of death in patients with neurofibromatosis type 1 (NF1). Early detection is crucial because complete surgical resection is the only curative treatment. It has been previously reported that an 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) image with a T/L (Tumor/Liver) SUVmax ratio > 1.5 provides a high negative predictive value; however, it is not specific enough to make a NF1-related MPNST diagnosis. A formal proof of malignant transformation from a histological analysis is necessary before surgical excision because the procedure can cause mutilation. The objective of the present work was to investigate the effectiveness of and complications associated with PET/CT-guided percutaneous biopsies for an NF1-related MPNST diagnosis.MethodsPET/CT-guided percutaneous biopsy procedures performed on 26 NF1 patients with a clinical suspicion of MPNST and a suspect lesion from a PET/CT scan (T/L SUVmax ratio > 1.5) were retrospectively evaluated. The localization of the suspected malignant site was determined using PET/CT. A stereotactic (ultrasonic and CT control) core biopsy technique was used with a local anesthesia.ResultsThe first PET/CT-guided percutaneous biopsies enabled a pathological diagnosis for all of the patients (no "inconclusive " results were obtained), and no secondary procedures were needed. Among the 26 patients, the histopathological results from the biopsy were malignant in 17 cases and benign (BPNST with atypical cells) in nine cases. No complications from the diagnostic procedure were observed. A surgical resection was performed in 18 patients (seven benign and 11 malignant biopsies), removing the fine needle biopsy scar. In addition, six locally advanced/metastatic MPNST were treated with chemo/radiotherapy, and two BPNST had no progression after a follow-up of 14 and 39 months, respectively. The PET/CT-guided percutaneous biopsy gave 25 accurate diagnoses and one false negative (BPNST with atypical cells on the biopsy and MPNST on the operated tumor), resulting in a diagnostic accuracy rate of 96%. This false negative case may be explained by the high heterogeneity of the tumor: benign areas were contiguous with the malignant ones and associated with inflammation.ConclusionsPET/CT-guided percutaneous biopsies are an effective and relatively non-traumatic procedure for diagnosis of NF1-related MPNST. It is the most reliable approach for early detection of MPNST.

P029. Does micro-invasion with DCIS on core biopsy from breast patients indicate whether sentinel lymph node biopsy (SLNB) should be performed?

P029. Does micro-invasion with DCIS on core biopsy from breast patients indicate whether sentinel lymph node biopsy (SLNB) should be performed?

Management of flat epithelial atypia on breast core biopsy may be individualized based on correlation with imaging studies

Flat epithelial atypia of the breast commonly co-exists with atypical ductal hyperplasia, lobular neoplasia, and indolent forms of invasive carcinomas such as tubular carcinoma. Most patients with pure flat epithelial atypia on core biopsy undergo surgical excision to evaluate for carcinoma in the adjacent breast tissue. Studies to date have reported varying upgrade rates with most recommending follow-up excision. These studies have often lacked detailed radiographic correlation, central review by breast pathologists and information regarding the biology of the carcinomas identified upon excision. In this study, we report the frequency of upgrade to invasive carcinoma or ductal carcinoma in situ in excision specimens following a diagnosis of pure flat epithelial atypia on core biopsy. Radiographic correlation is performed for each case and grade/receptor status of detected carcinomas is reported. Seventy-three (73) core biopsies containing pure flat epithelial atypia were identified from our files, meeting inclusion criteria for the study. In the subsequent excision biopsies, five (7%) cases contained invasive carcinoma or ductal carcinoma in situ and seventeen (23%) contained atypical ductal hyperplasia or lobular neoplasia. All of the ductal carcinoma in situ cases with estrogen receptor results were estrogen receptor positive and intermediate grade. The invasive tumors were small (pT1a) hormone receptor-positive, HER2-negative, low-grade invasive ductal or tubular carcinomas with negative sentinel lymph-node biopsies. No upgrades were identified in the 14 patients who had all of their calcifications removed by the stereotactic core biopsy. Our rate of upgrade to carcinoma, once cases with discordant imaging are excluded, is at the lower end of the range reported in the literature. Given the low upgrade rate and indolent nature of the carcinomas associated with flat epithelial atypia, case management may be individualized based on clinical and radiographic findings. Excision may not be necessary for patients without remaining calcifications following core biopsy.