High tumor infiltrating lymphocytes are significantly associated with pathological complete response in triple negative breast cancer treated with neoadjuvant KEYNOTE-522 chemoimmunotherapy.

INTRODUCTION: For patients with locally advanced triple negative breast cancer (TNBC), the standard of care is to administer the KEYNOTE-522 (K522) regimen, including chemotherapy and immunotherapy (pembrolizumab) given in the neoadjuvant setting. Pathological complete response (pCR) is more likely in patients who receive the K522 regimen than in patients who receive standard chemotherapy. Studies have shown that pCR is a strong predictor of long-term disease-free survival. However, factors predicting pCR to K522 are not well understood and require further study in real-world populations. METHODS: We evaluated 76 patients who were treated with the K522 regimen at our institution. Twenty-nine pre-treatment biopsy slides were available for pathology review. Nuclear grade, Nottingham histologic grade, Ki-67, lymphovascular invasion, and tumor infiltrating lymphocytes (TIL) were evaluated in these 29 cases. For the cases that did not have available slides for review from pre-treatment biopsies, these variables were retrieved from available pathology reports. In addition, clinical staging, race, and BMI at the time of biopsy were retrieved from all 76 patients' charts. Binary logistic regression models were used to correlate these variables with pCR. RESULTS: At the current time, 64 of 76 patients have undergone surgery at our institution following completion of K522 and 31 (48.4%) of these achieved pCR. In univariate analysis, only TIL was significantly associated with pCR (p = 0.014) and this finding was also confirmed in multivariate analysis, whereas other variables including age, race, nuclear grade, Nottingham grade, Ki-67, lymphovascular invasion, BMI, pre-treatment tumor size, and lymph node status were not associated with pCR (p > 0.1). CONCLUSION: Our real-world data demonstrates high TIL is significantly associated with pCR rate in the K522 regimen and may potentially serve as a biomarker to select optimal treatment. The pCR rate of 48.4% in our study is lower than that reported in K522, potentially due to the smaller size of our study; however, this may also indicate differences between real-world data and clinical trial results. Larger studies are warranted to further investigate the role of immune cells in TNBC response to K522 and other treatment regimens.

Changes in expression of breast cancer tumor biomarkers between primary tumors and corresponding metastatic sites: common patterns and relationships with survival.

PURPOSE: In metastatic breast cancer, differences in expression patterns of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2) between the primary tumor (PT) and metastatic site (MET) have been reported. However, there is limited understanding of the relationship of tumor subtype discordance and overall survival (OS). We evaluated patterns of ER/PR/HER2 in PTs and corresponding METs and assessed the relationship between these patterns and OS. METHODS: Patients diagnosed at our center with metastatic breast cancer (2011-2020) were included. ER/PR were stratified as < 1%/1-10%/ > 10% by immunohistochemistry and HER2 as positive/negative by immunohistochemistry/FISH. Tumor subtypes were classified as ER or PR + /HER2-, HER2+ , or triple-negative. Biomarker discordance data from PTs to METs were analyzed for expression patterns. OS was assessed. RESULTS: Of 254 patients, 41 (16.1%) had synchronous and 213 (83.9%) had metachronous METs. Category change of ER/PR/HER2 expression was observed in 56 (22.0%), 117 (40.5%), and 30 (11.8%) patients, respectively. Tumor subtype changed in 56 (22.0%) patients. We identified a difference between PT and MET from ER > 10% to ER < 1% (n = 28,16.2% p < 0.01); PR > 10% to PR < 1% (n = 54,48.2%, p < 0.001); PR > 10% to PR 1-10% (n = 18,16.1%, p < 0.001), and ER or PR+/HER2- to triple-negative (n = 19,13.0%, p = 0.03). In log-rank analysis, change from an ER or PR+/HER2- (5-year OS 88.6%) PT to a HER2+(67.5%) or triple-negative (54.6%) MET was associated with decreased survival (p < 0.01); however, in multivariate analysis, discordant biomarker expression was not associated with decreased survival (p > 0.05). CONCLUSION: Tumor expression of ER/PR/HER2 can differ between the PT and MET. Loss of ER/PR expression is common and may be related to worse survival. Routine assessment of MET tumor markers could inform prognosis and therapeutic decision-making.

Subspecialized breast pathologists have suboptimal interobserver agreement in Ki-67 evaluation using 20% as the cutoff.

PURPOSE: Ki-67 expression levels in breast cancer have prognostic and predictive significance. Therefore, accurate Ki-67 evaluation is important for optimal patient care. Although an algorithm developed by the International Ki-67 in Breast Cancer Working Group (IKWG) improves interobserver variability, it is tedious and time-consuming. In this study, we simplify IKWG algorithm and evaluate its interobserver agreement among breast pathologists in Ki-67 evaluation. METHODS: Six subspecialized breast pathologists (4 juniors, 2 seniors) assessed the percentage of positive cells in 5% increments in 57 immunostained Ki-67 slides. The time spent on each slide was recorded. Two rounds of ring study (R1, R2) were performed before and after training with the modified IKWG algorithm (eyeballing method at 400× instead of counting 100 tumor nuclei per area). Concordance was assessed using Kendall's and Kappa coefficients. RESULTS: Analysis of ordinal scale ratings for all categories with 5% increments showed almost perfect agreement in R1 (0.821) and substantial in R2 (0.793); Seniors and juniors had substantial agreement in R1 (0.718 vs. 0.649) and R2 (0.756 vs. 0.658). In dichotomous scale analysis using 20% as the cutoff, the overall agreement was moderate in R1 (0.437) and R2 (0.479), among seniors (R1: 0.436; R2: 0.437) and juniors (R1: 0.445; R2: 0.505). Average scoring time per case was higher in R2 (71 vs. 37 s). CONCLUSION: The modified IKWG algorithm does not significantly improve interobserver agreement. A better algorithm or assistance from digital image analysis is needed to improve interobserver variability in Ki-67 evaluation.

3D Oxide-Derived Ru Catalyst for Ultra-Efficient Hydrogenation of Levulinic Acid to γ-Valerolactone.

γ-valerolactone (GVL) is a key value-added chemical catalytically produced from levulinic acid (LA), an important biomass derivative platform chemical. Here an ultra-efficient 3D Ru catalyst generated by in situ reduction of RuZnOx nanoboxes is reported; the catalyst features a well-defined structure of highly dispersed in situ oxide-derived Ru (IOD-Ru) clusters (≈1 nm in size) spatially confined within the 3D nanocages with rich mesopores, which guarantees a maximized atom utilization with a high exposure of Ru active sites as well as a 3D accessibility for substrate molecules. The IOD-Ru exhibits ultrahigh performance for the hydrogenation of LA into GVL with a record-breaking turnover frequency (TOF) up to 59400 h-1 , 14 times higher than that of the ex situ reduction of RuZnOx nanoboxes catalyst. Structural characterizations and theoretical calculations collectively indicate that the defect-rich and coordination-unsaturated IOD-Ru sites can boost the activation of the carbonyl group in LA with a significantly lowered energy barrier of hydrogenation.

Correlation of HER2 Protein Level With mRNA Level Quantified by RNAscope in Breast Cancer.

Trastuzumab deruxtecan (T-DXd) has been approved by the US Food and Drug Administration (FDA) to treat patients with metastatic HER2-positive and HER2-low breast cancer, and clinical trials are examining its efficacy against early-stage breast cancer. Current HER2 immunohistochemical (IHC) assays are suboptimal in evaluating HER2-low breast cancers and identifying which patients would benefit from T-DXd. HER2 expression in 526 breast cancer tissue microarray (TMA) cores was measured using the FDA-approved PATHWAY and HercepTest IHC assays, and the corresponding RNA levels were evaluated by RNAscope. HER2 protein levels by regression analysis using a quantitative immunofluorescence score against cell line arrays with known HER2 protein levels determined by mass spectrometry were available in 48 of the cores. RNAscope was also performed in 32 metastatic biopsies from 23 patients who were subsequently treated with T-DXd, and the results were correlated with response rate. HER2 RNA levels by RNAscope strongly correlated with HER2 protein levels (P < .0001) and with HER2 IHC H-scores from the PATHWAY and HercepTest assays (P < .0001). However, neither protein levels nor RNA levels significantly differed between cases scored 0, ultralow, and 1+ by PATHWAY and HercepTest. The RNA levels were significantly higher (P = .030) in responders (6.4 ± 8.2 dots/cell, n = 12) than those in nonresponders (2.6 ± 2.2, n = 20) to T-DXd. RNAscope is a simple assay that can be objectively quantified and is a promising alternative to current IHC assays in evaluating HER2 expression in breast cancers, especially HER2-low cases, and may identify patients who would benefit from T-DXd.

Breast Cancer With HER2 Immunohistochemical Score 2 and Average HER2 Signals/Cell 6 or More and HER2/CEP17 Ratio Less Than 2 ('ISH Group 3'): A Multiinstitutional Cohort Analysis Emphasizing Outcome and Molecular Subtype.

Breast cancer (BC) with average human epidermal growth factor receptor 2 (HER2) signals/cell ≥6 and HER2/chromosome enumeration probe 17 (CEP17) ratio <2 (in situ hybridization [ISH] group 3) is very rare, accounting for 0.4% to 3.0% of cases sent for the dual-probe ISH assay. Although such patients are currently eligible for treatment with HER2-targeted therapy, their characteristics and outcomes remain poorly understood. Sixty-two BCs with equivocal HER2 immunohistochemical score (2+) and reflex ISH group 3 results were identified across 4 institutions. Available clinicopathologic characteristics, MammaPrint and BluePrint molecular results, and follow-up information were retrospectively analyzed. Most BCs with HER2 equivocal immunohistochemical and ISH group 3 results were histologic grade 2 or 3 (100%), estrogen receptor (ER) positive (90.3%), with an average HER2 signals/cell of 7.3. Molecular profiles revealed that 80% (16/20) of tumors were luminal subtypes, and HER2 molecular subtype was identified in 10% of tumors (2/20). Twelve (19.4%) out of 62 patients developed local recurrence and/or distant metastasis with a median follow-up of 50 months. One (10%) of 10 patients achieved pathologic complete response after neoadjuvant chemotherapy. Forty-nine (79%) out of 62 patients completed anti-HER2 agents, and exploratory analysis showed no statistically significant difference in disease outcomes between patients who completed anti-HER2 treatment and those who did not. Univariate analysis revealed advanced clinical stage, and ER/progesterone receptor negativity was associated with unfavorable disease outcomes, and exploratory multivariate analysis demonstrated that clinical stage was the most significant factor associated with disease outcomes in the studied population. These findings increase our understanding of this rare, but clinically important HER2 category. Large-scale prospective randomized studies are needed to further evaluate the role of perioperative HER2-targeted therapy in this patient population.

Reproducible Reporting of the Collection and Evaluation of Annotations for Artificial Intelligence Models.

This work puts forth and demonstrates the utility of a reporting framework for collecting and evaluating annotations of medical images used for training and testing artificial intelligence (AI) models in assisting detection and diagnosis. AI has unique reporting requirements, as shown by the AI extensions to the Consolidated Standards of Reporting Trials (CONSORT) and Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) checklists and the proposed AI extensions to the Standards for Reporting Diagnostic Accuracy (STARD) and Transparent Reporting of a Multivariable Prediction model for Individual Prognosis or Diagnosis (TRIPOD) checklists. AI for detection and/or diagnostic image analysis requires complete, reproducible, and transparent reporting of the annotations and metadata used in training and testing data sets. In an earlier work by other researchers, an annotation workflow and quality checklist for computational pathology annotations were proposed. In this manuscript, we operationalize this workflow into an evaluable quality checklist that applies to any reader-interpreted medical images, and we demonstrate its use for an annotation effort in digital pathology. We refer to this quality framework as the Collection and Evaluation of Annotations for Reproducible Reporting of Artificial Intelligence (CLEARR-AI).

Training pathologists to assess stromal tumour-infiltrating lymphocytes in breast cancer synergises efforts in clinical care and scientific research.

A growing body of research supports stromal tumour-infiltrating lymphocyte (TIL) density in breast cancer to be a robust prognostic and predicive biomarker. The gold standard for stromal TIL density quantitation in breast cancer is pathologist visual assessment using haematoxylin and eosin-stained slides. Artificial intelligence/machine-learning algorithms are in development to automate the stromal TIL scoring process, and must be validated against a reference standard such as pathologist visual assessment. Visual TIL assessment may suffer from significant interobserver variability. To improve interobserver agreement, regulatory science experts at the US Food and Drug Administration partnered with academic pathologists internationally to create a freely available online continuing medical education (CME) course to train pathologists in assessing breast cancer stromal TILs using an interactive format with expert commentary. Here we describe and provide a user guide to this CME course, whose content was designed to improve pathologist accuracy in scoring breast cancer TILs. We also suggest subsequent steps to translate knowledge into clinical practice with proficiency testing.

Initial interactions with the FDA on developing a validation dataset as a medical device development tool.

Quantifying tumor-infiltrating lymphocytes (TILs) in breast cancer tumors is a challenging task for pathologists. With the advent of whole slide imaging that digitizes glass slides, it is possible to apply computational models to quantify TILs for pathologists. Development of computational models requires significant time, expertise, consensus, and investment. To reduce this burden, we are preparing a dataset for developers to validate their models and a proposal to the Medical Device Development Tool (MDDT) program in the Center for Devices and Radiological Health of the U.S. Food and Drug Administration (FDA). If the FDA qualifies the dataset for its submitted context of use, model developers can use it in a regulatory submission within the qualified context of use without additional documentation. Our dataset aims at reducing the regulatory burden placed on developers of models that estimate the density of TILs and will allow head-to-head comparison of multiple computational models on the same data. In this paper, we discuss the MDDT preparation and submission process, including the feedback we received from our initial interactions with the FDA and propose how a qualified MDDT validation dataset could be a mechanism for open, fair, and consistent measures of computational model performance. Our experiences will help the community understand what the FDA considers relevant and appropriate (from the perspective of the submitter), at the early stages of the MDDT submission process, for validating stromal TIL density estimation models and other potential computational models. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

An African-specific polymorphism in the TP53 gene impairs p53 tumor suppressor function in a mouse model.

A nonsynonymous single-nucleotide polymorphism at codon 47 in TP53 exists in African-descent populations (P47S, rs1800371; referred to here as S47). Here we report that, in human cell lines and a mouse model, the S47 variant exhibits a modest decrease in apoptosis in response to most genotoxic stresses compared with wild-type p53 but exhibits a significant defect in cell death induced by cisplatin. We show that, compared with wild-type p53, S47 has nearly indistinguishable transcriptional function but shows impaired ability to transactivate a subset of p53 target genes, including two involved in metabolism:Gls2(glutaminase 2) and Sco2 We also show that human and mouse cells expressing the S47 variant are markedly resistant to cell death by agents that induce ferroptosis (iron-mediated nonapoptotic cell death). We show that mice expressing S47 in homozygous or heterozygous form are susceptible to spontaneous cancers of diverse histological types. Our data suggest that the S47 variant may contribute to increased cancer risk in individuals of African descent, and our findings highlight the need to assess the contribution of this variant to cancer risk in these populations. These data also confirm the potential relevance of metabolism and ferroptosis to tumor suppression by p53.

Intraoperative assessment of axillary sentinel lymph nodes by telepathology.

PURPOSE: Although axillary dissection is no longer indicated for many breast cancer patients with 1-2 positive axillary sentinel lymph nodes (ASLN), intraoperative ASLN assessment is still performed in many institutions for patients undergoing mastectomy or neoadjuvant therapy. With recent advancements in digital pathology, pathologists increasingly evaluate ASLN via remote telepathology. We aimed to compare the performance characteristics of remote telepathology and conventional on-site intraoperative ASLN assessment. METHODS: Data from ASLN evaluation for breast cancer patients performed at two sites between April 2021 and October 2022 was collated. Remote telepathology consultation was conducted via the Aperio eSlideManager system. RESULTS: A total of 385 patients were identified during the study period (83 telepathology, 302 on-site evaluations). Although not statistically significant (P = 0.20), the overall discrepancy rate between intraoperative and final diagnoses was slightly higher at 9.6% (8/83) for telepathology compared with 5.3% (16/302) for on-site assessment. Further comparison of performance characteristics of ASLN assessment between telepathology and conventional on-site evaluation revealed no statistically significant differences between deferral rates, discrepancy rates, interpretive or sampling errors, major or minor disagreements, false negative or false positive results as well as clinical impact and turn-around time (P ≥ 0.12). CONCLUSION: ASLN assessment via telepathology is not significantly different from conventional on-site evaluation, although it shows a slightly higher overall discrepancy rate between intraoperative and final diagnoses (9.6% vs. 5.3%). Further studies are warranted to ensure accuracy of ASLN assessment via telepathology.

Clinicopathologic Predictors of Clinical Outcomes in Mammary Adenoid Cystic Carcinoma: A Multi-institutional Study.

Adenoid cystic carcinoma (AdCC) is an uncommon type of invasive breast carcinoma with a favorable prognosis. However, some cases are aggressive. The study aims to define the clinicopathologic predictors of outcome. Clinical, radiological, and pathologic variables were recorded for 76 AdCC cases from 11 institutions. The following histologic characteristics were evaluated by the breast pathologist in each respective institution, including Nottingham grade (NG), percentages of various growth patterns (solid, cribriform, trabecular-tubular), percentage of basaloid component, tumor borders (pushing, infiltrative), perineural invasion, lymphovascular invasion, necrosis, and distance from the closest margin. Various grading systems were evaluated, including NG, salivary gland-type grading systems, and a new proposed grading system. The new grading system incorporated the growth pattern (percent solid, percent cribriform), percent basaloid morphology, and mitotic count using the Youden index criterion. All variables were correlated with recurrence-free survival. Nineteen (25%) women developed local and/or distant recurrence. Basaloid morphology (≥25% of the tumor) was identified in 20 (26.3%) cases and a solid growth pattern (using ≥60% cutoff) in 22 (28.9%) cases. In the univariate analysis, the following variables were significantly correlated with worse recurrence-free survival: solid growth pattern, basaloid morphology, lymphovascular invasion, necrosis, perineural invasion, and pN-stage. In the multivariate analysis including basaloid morphology, pN-stage, lymphovascular invasion, and perineural invasion, basaloid morphology was statistically significant, with a hazard ratio of 3.872 (95% CI, 1.077; 13.924; P =.038). The NG and the new grading system both correlated with recurrence-free survival. However, grade 2 had a similar risk as grade 3 in the NG system and a similar risk as grade 1 in the new grading system. For solid growth patterns and basaloid morphology, using a 2-tier system with 1 cutoff was better than a 3-tier system with 2 cutoffs. Basaloid morphology and solid growth pattern have prognostic values for AdCC, with a 2-tier grading system performing better than a 3-tier system.

The Role of Artificial Intelligence in Accurate Interpretation of HER2 Immunohistochemical Scores 0 and 1+ in Breast Cancer.

The new human epidermal growth factor receptor (HER)2-targeting antibody-drug conjugate offers the opportunity to treat patients with HER2-low breast cancer. Distinguishing HER2 immunohistochemical (IHC) scores of 0 and 1+ is not only critical but also challenging owing to HER2 heterogeneity and variability of observers. In this study, we aimed to increase the interpretation accuracy and consistency of HER2 IHC 0 and 1+ evaluation through assistance from an artificial intelligence (AI) algorithm. In addition, we examined the value of our AI algorithm in evaluating HER2 IHC scores in tumors with heterogeneity. AI-assisted interpretation consisted of AI algorithms and an augmenting reality module with a microscope. Fifteen pathologists (5 junior, 5 midlevel, and 5 senior) participated in this multi-institutional 2-round ring study that included 246 infiltrating duct carcinoma cases that were not otherwise specified. In round 1, pathologists analyzed 246 HER2 IHC slides by microscope without AI assistance. After a 2-week washout period, the pathologists read the same slides with AI algorithm assistance and rendered the definitive results by adjusting to the AI algorithm. The accuracy of interpretation accuracy with AI assistance (0.93 vs 0.80), thereby the evaluation precision of HER2 0 and the recall of HER2 1+. In addition, the AI algorithm improved the total consistency (intraclass correlation coefficient = 0.542-0.812), especially in HER2 1+ cases. In cases with heterogeneity, accuracy improved significantly (0.68 to 0.89) and to a similar level as in cases without heterogeneity (accuracy, 0.97). Both accuracy and consistency improved more for junior pathologists than those for the midlevel and senior pathologists. To the best of our knowledge, this is the first study to show that the accuracy and consistency of HER2 IHC 0 and 1+ evaluation and the accuracy of HER2 IHC evaluation in breast cancers with heterogeneity can be significantly improved using AI-assisted interpretation.

Low-grade adenosquamous carcinoma of the breast: a clinical, morphological and immunohistochemical analysis of 25 patients.

AIMS: Due to its rarity and non-specific clinical and pathological features, low-grade adenosquamous carcinoma (LGASC) of the breast continues to pose diagnostic challenges. Unlike other triple-negative breast carcinomas, LGASC tends to have an indolent clinical behaviour. It is essential to recognise this lesion for accurate diagnosis and appropriate management. METHODS AND RESULTS: Twenty-five cases of LGASC were identified in our archives and collaborating institutes. Cases of LGASC with dominant coexisting other type carcinomas were excluded. We studied the clinical presentation, morphological features, patterns of the commonly used immunohistochemical stains and follow-up. In our cohort, LGASC was commonly located at the outer aspect of the breast and associated with intraductal papilloma. The morphology of LGASC is characterised by infiltrating small glands and nests with variable squamous differentiation. We also found cuffing desmoplastic (fibrolamellar) stromal change in 75% of patients and peripheral lymphocytic aggregates in 87.5% of patients. P63 and smooth muscle myosin (SMM) were the most common myoepithelial markers used to assist in diagnosis. P63 often stained peripheral tumour cells surrounding invasive glands (circumferential staining in 80% of the cases), mimicking myoepithelial cells. It also stained the small nests with squamous differentiation. However, SMM was negative in 63% of the cases. The vast majority of our cases were triple-negative; only a few had focal and weak expressions of ER and PR. One patient who did not have excision developed lymph node metastasis. Most patients underwent excision or mastectomy with negative margins as surgical treatment; there were no recurrences or metastases in these patients with clinical follow-ups up to 108 months. CONCLUSIONS: LGASC has some unique, although not entirely specific, morphological features and immunohistochemical staining patterns. Fibrolamellar stromal change, peripheral lymphocytic aggregates and variable staining of p63 and SMM are valuable features to facilitate the diagnosis.

Synthesis of 3-Haloindoles via Cascade Oxidative Cyclization/Halogenation of 2-Alkenylanilines Mediated by PIDA and LiBr/KI.

The treatment of 2-alkenylanilines with phenyliodine(III) diacetate (PIDA) and LiBr or KI in HFIP was found to afford the corresponding 3-haloindoles via cascade oxidative cyclization/halogenation encompassing oxidative C-N/C-X (X = Br, I) bond formations. A plausible mechanism involving the in situ formation of the reactive AcO-X (X = Br, I) from the reaction of PIDA and LiBr/KI was postulated.

Utility of Oncotype DX score in clinical management for T1 estrogen receptor positive, HER2 negative, and lymph node negative breast cancer.

BACKGROUND: The management of estrogen receptor positive (ER+)/HER2- and lymph node (LN) negative breast cancers can be influenced by Oncotype DX recurrence score (RS) in the USA. However, the benefit of RS in T1 tumors (≤ 1 cm) is not clear. METHODS: We retrieved 199 T1 ER+/HER2-/LN- breast cancer diagnosed between 1993 and 2016 that had undergone RS testing. The median follow-up time was 51 months. We examined the disease-free survival (DFS) and distant metastasis and their association with RS and other clinicopathologic features. RESULTS: Of the 199 cases, 40 were T1a (≤ 0.5 cm) and 159 were T1b (> 0.5 cm to 1 cm) tumors. In the 40 T1a tumors, 11 would benefit from chemotherapy by the TAILORx study results. Of these T1a tumors, 36 were Nottingham grade 1/2, 3 were grade 3, and 1 was microinvasive carcinoma; 2 (5%) had local recurrence and 1 (2.5%) had distant metastasis to the bone. The only patient with T1a tumor (Nottingham grade 3, RS = 42) and distant metastasis to bone had received adjuvant chemotherapy. In the 159 T1b tumors, 25 would benefit chemotherapy by the TAILORx results. Of the T1b tumors, 149 were Nottingham grade 1/2 and 10 were grade 3. Nine (5.7%) had local recurrence and 2 (1.3%) had distant metastasis to bone and mediastinum, respectively. The two T1b tumors with distant metastasis had a RS 20 and Nottingham grade 2, and RS 27 and Nottingham grade 3, respectively. Both patients received adjuvant chemotherapy. In multivariate analysis of the entire cohort (T1a and T1b tumors), Nottingham tumor grade and receiving chemotherapy were significantly associated with DFS. In univariate analysis of the entire cohort, Nottingham tumor grade, receiving adjuvant chemotherapy, and RS were significantly associated with distant metastasis. CONCLUSION: This study demonstrates that the metastatic rate of T1a and T1b ER+/HER2-/LN- breast cancer is very low. Patients with low grade (1 or 2), T1a ER+/HER2-/LN- breast cancer may not need RS for treatment decision-making; however, in patients with high-grade T1a or T1b ER+/HER2-/LN- breast cancer, RS analysis should be strongly considered.

Comparison of diagnostic accuracy and utility of artificial intelligence-optimized ACR TI-RADS and original ACR TI-RADS: a multi-center validation study based on 2061 thyroid nodules.

OBJECTIVE: To determine if artificial intelligence-based modification of the Thyroid Imaging Reporting Data System (TI-RADS) would be better than the current American College of Radiology (ACR) TI-RADS for risk stratification of thyroid nodules. METHODS: A total of 2061 thyroid nodules (in 1859 patients) sampled with fine-needle aspiration or operation were retrospectively analyzed between January 2017 and July 2020. Two radiologists blinded to the pathologic diagnosis evaluated nodule features in five ultrasound categories and assigned TI-RADS scores by both ACR TI-RADS and AI TI-RADS. Inter-rater agreement was assessed by asking another two radiologists to score a set of 100 nodules independently. The reference standard was postoperative pathological or cytopathological diagnosis according to the Bethesda system. Inter-rater agreement was determined using intraclass correlation coefficient (ICC). RESULTS: AI TI-RADS assigned lower TI-RADS risk levels than ACR TI-RADS (p < 0.001) and had larger area under receiver operating characteristic curve (0.762 vs. 0.679, p < 0.001). The sensitivities of ACR TI-RADS and AI TI-RADS were similar (86.7% vs. 82.2%, p = 0.052), but specificity was higher with AI TI-RADS (70.2% vs. 49.2%, p < 0.001). AI TI-RADS downgraded 743 (48.63%) benign nodules, indicating that 328 (42.3% of 776 biopsied nodules) unnecessary fine-needle aspirations (FNA) could have been avoided. Inter-rater agreement was better with AI TI-RADS than with ACR TI-RADS (ICC, 0.808 vs. 0.861, p < 0.001). CONCLUSION: AI TI-RADS can achieve meaningful reduction in the number of benign thyroid nodules recommended for biopsy and significantly improve specificity despite a slight decrease in sensitivity. KEY POINTS: • AI TI-RADS assigned lower TI-RADS risk levels than ACR TI-RADS, showing similar sensitivity but higher specificity. • Half of the benign nodules can be downgraded of which 42.3% of biopsy nodules avoided unnecessary fine-needle aspiration (FNA). • AI TI-RADS had a better overall inter-rater agreement.

Contrast-Enhanced Ultrasound Using Perfluorobutane: Impact of Proposed Modified LI-RADS Criteria on Hepatocellular Carcinoma Detection.

BACKGROUND. Contrast-enhanced ultrasound (CEUS) LI-RADS version 2017 (v2017) applies only to CEUS examinations performed using pure blood pool agents, noting that future versions will address combined blood pool and Kupffer cell agents such as perfluorobutane. Such agents may improve hepatocellular carcinoma (HCC) detection by visualization of a defect in the Kupffer phase (obtained ≥ 10 minutes after injection). OBJECTIVE. The purpose of our study was to compare the diagnostic performance of the LR-5 category for HCC detection in at-risk patients between CEUS LI-RADS v2017 and proposed modified criteria for CEUS examinations performed using perfluorobutane. METHODS. This retrospective study included 293 patients at risk for HCC (259 men, 34 women; mean age, 55 ± 12 [SD] years) who underwent CEUS using perfluorobutane from March 1, 2020, to October 30, 2020, showing a total of 304 observations (274 HCC, 14 non-HCC malignancy, and 16 benign lesions). Two readers independently assessed examinations and assigned categories using both CEUS LI-RADS v2017 and the proposed modified criteria. In the modified criteria, observations 10 mm or greater with not rim arterial phase hyperenhancement (APHE), no washout, and a Kupffer defect were upgraded from LR-4 to LR-5, and observations 10 mm or greater with not rim APHE, early washout, and a mild Kupffer defect were reassigned from LR-M to LR-5. Interreader agreement was assessed, and consensus interpretations were reached. Diagnostic performance was evaluated. RESULTS. Interreader agreement for LI-RADS category assignments, expressed using kappa coefficients, was 0.839 for CEUS LI-RADS v2017 and 0.854 for the modified criteria. Modified criteria upgraded 35 observations from LR-4 to LR-5 on the basis of a Kupffer defect, of which 34 were HCC and one was benign. Modified criteria reassigned 22 observations from LR-M to LR-5 on the basis of a mild Kupffer defect, of which all were HCC. LR-5 using modified criteria, compared with CEUS LI-RADS v2017, had significantly increased sensitivity (89% vs 69%, p < .001), a nonsignificant decrease in specificity (83% vs 87%, p > .99), and significantly increased accuracy (89% vs 71%, p < .001) for HCC. CONCLUSION. When using perfluorobutane for CEUS in at-risk patients, modified criteria incorporating Kupffer defects significantly improve sensitivity without significant loss of specificity in HCC detection. CLINICAL IMPACT. Future CEUS LI-RADS updates seeking to address the use of combined blood pool and Kupffer cell agents should consider adoption of the explored criteria.

Management of high-risk breast lesions diagnosed on core biopsies and experiences from prospective high-risk breast lesion conferences at an academic institution.

BACKGROUND: The management of high-risk breast lesions diagnosed on image-guided core biopsy remains controversial. We implemented a high-risk breast conference attended by breast pathologists, imagers, and surgeons to prospectively review all contemporary cases in order to provide a consensus recommendation to either surgically excise or follow on imaging at 6-month intervals for a minimum of 2 years. METHODS: Between May, 2015 and June, 2019, 127 high-risk lesions were discussed. Of these 127 cases, 116 had concordant radiology-pathology (rad-path) findings. The remaining 11 patients had discordant rad-path findings. Of the 116 concordant cases, 6 were excluded due to lack of the first imaging follow-up until analysis. Of the remaining 110 patients, 43 had atypical ductal hyperplasia (ADH), 12 had lobular carcinoma in situ (LCIS), 19 had atypical lobular hyperplasia (ALH), 33 had radial scar (RS), 2 had flat epithelial atypia (FEA), and 1 had mucocele-like lesion (ML). We recommended excision for ADH if there were > 2 ADH foci or < 90% of the associated calcifications were removed. For patients with LCIS or ALH, we recommended excision if the LCIS or ALH was associated with microcalcifications or the LCIS was extensive. We recommended excision of RS when < 1/2 of the lesion was biopsied. We recommended all patients with FEA and ML for 6-month follow-up. RESULTS: Following conference-derived consensus for excision, of the 27 ADH excised, 9 were upgraded to invasive carcinoma or ductal carcinoma in situ. Of the six LCIS cases recommended for excision, none were upgraded. Nine excised radial scars revealed no upgrades. Additionally, 3 patients with ADH, 2 with ALH, 1 with LCIS, and 2 with RS underwent voluntary excision, and none were upgraded. All other patients (13 with ADH, 5 LCIS, 17 ALH, 22 RS, 2 FEA and 1 ML) were followed with imaging, and none revealed evidence of disease progression during follow-up (187-1389 days). All 11 rad-path discordant cases were excised with 2 upgraded to carcinoma. CONCLUSIONS: The results of this prospective study indicate that high-risk breast lesions can be successfully triaged to surgery versus observation following establishment of predefined firm guidelines and performance of rigorous rad-path correlation.

ANETT: PhAse II trial of NEoadjuvant TAK-228 plus Tamoxifen in patients with hormone receptor-positive breast cancer.

INTRODUCTION: Neoadjuvant endocrine therapy is often utilized to downstage Estrogen Receptor-positive (ER+) breast cancer prior to surgery. However, this approach is sometimes met with endocrine resistance mechanisms within the tumor. This trial examines the safety and efficacy of tamoxifen in combination with an mTORC1/2 inhibitor, TAK-228, in the neoadjuvant treatment of ER+ breast cancer. METHODS: In this single-arm, open-label trial, pre- and post-menopausal women were enrolled to receive neoadjuvant tamoxifen (20 mg daily) with TAK-228 (30 mg weekly) for 16 weeks prior to surgery. Patient had tissue sampling at baseline, week 6, and week 16. The primary endpoint was change in Ki-67 from baseline to 6 weeks. The toxicity, change in tumor size, pathologic complete response rate, PEPI score, and baseline Oncotype Dx score were also assessed. RESULTS: Twenty-eight women were enrolled on the trial, and 25 completed the entire study course. The combination of tamoxifen and TAK-228 resulted in a significant reduction in Ki-67 from 18.3 to 15.2% (p = 0.0023). The drug was also found to be safe and tolerable. While nausea and hyperglycemia were common side effects, these were manageable. The tumor size also significantly decreased with the treatment, with a median decrease of 0.75 cm (p < 0.0001). There were no pathologic complete responses. CONCLUSION: Tamoxifen and TAK-228 was safe and well tolerated neoadjuvant treatment for ER+ breast cancer, preliminary evidence of activity with significant reduction in both Ki-67 and tumor size, warranting further evaluation in a larger study.