Author Correction: Landscape of somatic mutations in 560 breast cancer whole-genome sequences.

In the Methods section of this Article, 'greater than' should have been 'less than' in the sentence 'Putative regions of clustered rearrangements were identified as having an average inter-rearrangement distance that was at least 10 times greater than the whole-genome average for the individual sample. '. The Article has not been corrected.

Epigenetic activation of SOX11 is associated with recurrence and progression of ductal carcinoma in situ to invasive breast cancer.

BACKGROUND: Risk of recurrence and progression of ductal carcinoma in situ (DCIS) to invasive cancer remains uncertain, emphasizing the need for developing predictive biomarkers of aggressive DCIS. METHODS: Human cell lines and mouse models of disease progression were analyzed for candidate risk predictive biomarkers identified and validated in two independent DCIS cohorts. RESULTS: RNA profiling of normal mammary and DCIS tissues (n = 48) revealed that elevated SOX11 expression correlates with MKI67, EZH2, and DCIS recurrence score. The 21T human cell line model of DCIS progression to invasive cancer and two mouse models developing mammary intraepithelial neoplasia confirmed the findings. AKT activation correlated with chromatin accessibility and EZH2 enrichment upregulating SOX11 expression. AKT and HER2 inhibitors decreased SOX11 expression along with diminished mammosphere formation. SOX11 was upregulated in HER2+ and basal-like subtypes (P < 0.001). Longitudinal DCIS cohort (n = 194) revealed shorter recurrence-free survival in SOX11+ than SOX11- patients (P = 0.0056 in all DCIS; P < 0.0001 in HER2+ subtype) associated with increased risk of ipsilateral breast event/IBE (HR = 1.9, 95%CI = 1.2-2.9; P = 0.003). DISCUSSION: Epigenetic activation of SOX11 drives recurrence of DCIS and progression to invasive cancer, suggesting SOX11 as a predictive biomarker of IBE.

Immunohistochemical assessment of HER2 low breast cancer: interobserver reproducibility and correlation with digital image analysis.

PURPOSE: The recent findings from the DESTINY-Breast04 trial highlighted the clinical importance of distinguishing between HER2 immunohistochemistry (IHC) scores 0 and 1 + in metastatic breast cancer (BC). However, pathologist interpretation of HER2 IHC scoring is subjective, and standardized methodology is needed. We evaluated the consistency of HER2 IHC scoring among pathologists and the accuracy of digital image analysis (DIA) in interpreting HER2 IHC staining in cases of HER2-low BC. METHODS: Fifty whole-slide biopsies of BC with HER2 IHC staining were evaluated, comprising 25 cases originally reported as IHC score 0 and 25 as 1 +. These slides were digitally scanned. Six pathologists with breast expertise independently reviewed and scored the scanned images, and DIA was applied. Agreement among pathologists and concordance between pathologist scores and DIA results were statistically analyzed using Kendall coefficient of concordance (W) tests. RESULTS: Substantial agreement among at least five of the six pathologists was found for 18 of the score 0 cases (72%) and 15 of the score 1 + cases (60%), indicating excellent interobserver agreement (W = 0.828). DIA scores were highly concordant with pathologist scores in 96% of cases (47/49), indicating excellent concordance (W = 0.959). CONCLUSION: Although breast subspecialty pathologists were relatively consistent in evaluating BC with HER2 IHC scores of 0 and 1 +, DIA may be a reliable supplementary tool to enhance the standardization and quantification of HER2 IHC assessment, especially in challenging cases where results may be ambiguous (i.e., scores 0-1 +). These findings hold promise for improving the accuracy and consistency of HER2 testing.

Best practices for achieving consensus in HER2-low expression in breast cancer: current perspectives from practising pathologists.

AIMS: Human epidermal growth factor receptor 2 (HER2) expression is an important biomarker in breast cancer (BC). Most BC cases categorised as HER2-negative (HER2-) express low levels of HER2 [immunohistochemistry (IHC) 1+ or IHC 2+/in-situ hybridisation not amplified (ISH-)] and represent a clinically relevant therapeutic category that is amenable to targeted therapy using a recently approved HER2-directed antibody-drug conjugate. A group of practising pathologists, with expertise in breast pathology and BC biomarker testing, outline best practices and guidance for achieving consensus in HER2 IHC scoring for BC. METHODS AND RESULTS: The authors describe current knowledge and challenges of IHC testing and scoring of HER2-low expressing BC and provide best practices and guidance for accurate identification of BCs expressing low levels of HER2. These expert pathologists propose an algorithm for assessing HER2 expression with validated IHC assays and incorporate the 2023 American Society of Clinical Oncology and College of American Pathologist guideline update. The authors also provide guidance on when to seek consensus for HER2 IHC scoring, how to incorporate HER2-low into IHC reporting and present examples of HER2 IHC staining, including challenging cases. CONCLUSIONS: Awareness of BC cases that are negative for HER protein overexpression/gene amplification and the related clinical relevance for targeted therapy highlight the importance of accurate HER2 IHC scoring for optimal treatment selection.

Concordance between pathologists and between specimen types in detection of HER2-low breast carcinoma by immunohistochemistry.

CONTEXT: Recent clinical trials indicate that HER2-targeted therapy may benefit HER2-low breast cancer patients including HER2 score 1+ or 2+ and no gene amplification. Concordance between pathologists and between core biopsy and surgical excision in establishing HER2-low status was evaluated. DESIGN: 57 patients with HER2 negative breast cancer (IHC 0, 1+, or 2+, no gene amplification) by core biopsy were included. Core biopsy and representative tumor from corresponding surgical excision was immunostained for HER2. Original HER2 IHC scores were interpreted using 2018 guidelines. Three pathologists independently interpreted again under 2023 guidelines. Kappa statistic evaluated agreement of HER2 IHC scores. RESULTS: Applying 2023 guidelines, HER2 IHC scores were concordant among study pathologists in 46 of 57 (81 %) core biopsy and 50 of 57 (88 %) surgical resections. Kappa statistics were 0.78 and 0.85 (substantial agreement), for inter-pathologist agreement of core biopsy and surgical resections under 2023 guidelines; 0.55 (moderate agreement) for agreement between first interpretation by 2018 guidelines and second interpretation by 2023 guidelines; and 0.13 (slight agreement) for agreement in HER2 consensus scores between outside core and surgical resection and 0.49 (moderate agreement) for inside core and surgical resection. Low HER2 expression was found in 28 of 57 (49 %) core biopsy and in 25 of 57 (44 %) surgical excisions. CONCLUSIONS: Interobserver agreement among study pathologists was good in core biopsy and surgical excisions, applying updated 2023 guidelines. Intratumoral heterogeneity in protein expression and preanalytical factors may result in variable identification of HER2-low status in core biopsy and surgical excision specimens.

High-fat diet, but not duration of lactation, increases mammary gland lymphatic vessel function and subsequent growth of inflammatory breast cancer cells.

Inflammatory breast cancer (IBC) presents as rapid-onset swelling and breast skin changes caused by tumor emboli in the breast and breast skin lymphatics. IBC has been linked with obesity and duration of breastfeeding, but how these factors affect IBC tumor progression is not clear. We modeled the simultaneous effects of diet and weaning in mice on in vivo lymphatic function; on IBC tumor growth; and on aspects of the mammary gland microenvironment before and after IBC (SUM149) xenograft inoculation. We hypothesized that weaning status and diet would have synergistic effects on lymphatic function and the breast microenvironment to enhance IBC tumor growth. Changes in lymphatic structure and function were characterized with in vivo near-infrared fluorescence (NIRF) imaging. Mice were fed either a high-fat diet (HFD; 60 kcal%) or a normal/low-fat diet (LFD; 10 kcal%), bred twice, and subjected to either normal-duration nursing (NW) or forced weaning (FW). SUM149 IBC tumors were implanted at 14 months; images were obtained before and after implantation. Multiparous mice fed HFD showed increased pre-tumor lymphatic pulsing in both the FW and NW groups relative to mice fed LFD. HFD promoted tumor growth independent of weaning time (P = 0.04). Pre-tumor lymphatic pulsing was associated with tumor volume at 8 weeks (P = 0.02) and was significantly correlated with expression of the lymphatic tracking ligand CCL21 (P = 0.05, Table 1). HFD significantly increased the numbers of monocyte-derived IBA1+, CD163+, and CD11c+ cells (P < 0.0001, P < 0.0001, P = 0.0005) in the contralateral, non-tumor-bearing mammary gland. Numbers of lymphangiogenic podoplanin+/IBA1+ macrophages were increased in the ducts of HFD and FW mice (all P < 0.003). HFD in nulliparous mice had a similar increase in lymphatic pulsing at 14 weeks (P = 0.006), indicating that this functional change was independent of parity. We conclude that HFD induced increases in mammary gland lymphatic function, assessed as pulsing rate before tumor initiation, and correlated with inflammation in the mammary gland and increased SUM149 tumor growth. The relationship between diet, lymphatic pulsing, and tumor growth warrants further investigation.

Eliminating breast surgery for invasive breast cancer in exceptional responders to neoadjuvant systemic therapy: a multicentre, single-arm, phase 2 trial.

BACKGROUND: Neoadjuvant systemic therapy (NST) for triple-negative breast cancer and HER2-positive breast cancer yields a pathological complete response in approximately 60% of patients. A pathological complete response to NST predicts an excellent prognosis and can be accurately determined by percutaneous image-guided vacuum-assisted core biopsy (VACB). We evaluated radiotherapy alone, without breast surgery, in patients with early-stage triple-negative breast cancer or HER2-positive breast cancer treated with NST who had an image-guided VACB-determined pathological complete response. METHODS: This multicentre, single-arm, phase 2 trial was done in seven centres in the USA. Women aged 40 years or older who were not pregnant with unicentric cT1-2N0-1M0 triple-negative breast cancer or HER2-positive breast cancer and a residual breast lesion less than 2 cm on imaging after clinically standard NST were eligible for inclusion. Patients had one biopsy (minimum of 12 cores) obtained by 9G image-guided VACB of the tumour bed. If no invasive or in-situ disease was identified, breast surgery was omitted, and patients underwent standard whole-breast radiotherapy (40 Gy in 15 fractions or 50 Gy in 25 fractions) plus a boost (14 Gy in seven fractions). The primary outcome was the biopsy-confirmed ipsilateral breast tumour recurrence rate determined using the Kaplan-Meier method assessed in the per-protocol population. Safety was assessed in all patients who received VACB. This study has completed accrual and is registered with ClinicalTrials.gov, NCT02945579. FINDINGS: Between March 6, 2017, and Nov 9, 2021, 58 patients consented to participate; however, four (7%) did not meet final inclusion criteria and four (7%) withdrew consent. 50 patients were enrolled and underwent VACB following NST. The median age of the enrolled patients was 62 years (IQR 55-77); 21 (42%) patients had triple-negative breast cancer and 29 (58%) had HER2-positive breast cancer. VACB identified a pathological complete response in 31 patients (62% [95% CI 47·2-75·4). At a median follow-up of 26·4 months (IQR 15·2-39·6), no ipsilateral breast tumour recurrences occurred in these 31 patients. No serious biopsy-related adverse events or treatment-related deaths occurred. INTERPRETATION: Eliminating breast surgery in highly selected patients with an image-guided VACB-determined pathological complete response following NST is feasible with promising early results; however, additional prospective clinical trials evaluating this approach are needed. FUNDING: US National Cancer Institute (National Institutes of Health).

Comprehensive multiplexed immune profiling of the ductal carcinoma in situ immune microenvironment regarding subsequent ipsilateral invasive breast cancer risk.

BACKGROUND: Ductal carcinoma in situ (DCIS) is treated to prevent subsequent ipsilateral invasive breast cancer (iIBC). However, many DCIS lesions will never become invasive. To prevent overtreatment, we need to distinguish harmless from potentially hazardous DCIS. We investigated whether the immune microenvironment (IME) in DCIS correlates with transition to iIBC. METHODS: Patients were derived from a Dutch population-based cohort of 10,090 women with pure DCIS with a median follow-up time of 12 years. Density, composition and proximity to the closest DCIS cell of CD20+ B-cells, CD3+CD8+ T-cells, CD3+CD8- T-cells, CD3+FOXP3+ regulatory T-cells, CD68+ cells, and CD8+Ki67+ T-cells was assessed with multiplex immunofluorescence (mIF) with digital whole-slide analysis and compared between primary DCIS lesions of 77 women with subsequent iIBC (cases) and 64 without (controls). RESULTS: Higher stromal density of analysed immune cell subsets was significantly associated with higher grade, ER negativity, HER-2 positivity, Ki67 ≥ 14%, periductal fibrosis and comedonecrosis (P < 0.05). Density, composition and proximity to the closest DCIS cell of all analysed immune cell subsets did not differ between cases and controls. CONCLUSION: IME features analysed by mIF in 141 patients from a well-annotated cohort of pure DCIS with long-term follow-up are no predictors of subsequent iIBC, but do correlate with other factors (grade, ER, HER2 status, Ki-67) known to be associated with invasive recurrences.

Feasibility of using digital confocal microscopy for cytopathological examination in clinical practice.

Optical imaging modalities are emerging as digital microscopy tools for tissue examination. The investigation of these techniques for potential applications in anatomic pathology practice has focused primarily on surgical pathology and has not included cytopathological specimens. We evaluated the feasibility of using digital confocal microscopy (CM) to examine cytopathological specimens. Smears and cell suspensions collected in RPMI solution were prepared from tissue scrapes obtained from surgical resections of breast, lung, liver, and kidney. Air-dried smears and cell pellets obtained from centrifugation of the cell suspensions were stained with 0.6 mM acridine orange and imaged with a CM platform. After completion of imaging, the smears were stained with Diff-Quik (DQ), and cell pellets were routinely processed, embedded in paraffin wax, cut, and stained with hematoxylin and eosin (H&E). We evaluated the mean time to acquire digital CM images; quality of images based on the extent of tissue recognition (0%, grade 0; 1-19%, grade 1; 20-50%, grade 2; >50%, grade 3); comparison of images with DQ- and H&E-stained specimens; and ability to make specific diagnoses. We imaged 91 smears and 52 cell pellets and acquired digital CM images within 2-3 min, with 92% and 88% of images, respectively, from smears and cell pellets showing grade 3 quality. On the basis of CM images, 8 smears (9%) and 7 cell pellets (14%) were categorized as benign, and 83 (91%) and 45 (88%), respectively, as malignant. Specific diagnoses were made by using digital CM images of smears and cell pellets that matched accurately with corresponding DQ- and H&E-stained preparations. The results of our first feasibility study clearly indicated the utility of CM as a next-generation digital microscopy tool for evaluating cytology specimens. Prospective clinical studies are warranted for validating our findings for potential incorporation into cytopathological clinical practice.

Landscape of somatic mutations in 560 breast cancer whole-genome sequences.

We analysed whole-genome sequences of 560 breast cancers to advance understanding of the driver mutations conferring clonal advantage and the mutational processes generating somatic mutations. We found that 93 protein-coding cancer genes carried probable driver mutations. Some non-coding regions exhibited high mutation frequencies, but most have distinctive structural features probably causing elevated mutation rates and do not contain driver mutations. Mutational signature analysis was extended to genome rearrangements and revealed twelve base substitution and six rearrangement signatures. Three rearrangement signatures, characterized by tandem duplications or deletions, appear associated with defective homologous-recombination-based DNA repair: one with deficient BRCA1 function, another with deficient BRCA1 or BRCA2 function, the cause of the third is unknown. This analysis of all classes of somatic mutation across exons, introns and intergenic regions highlights the repertoire of cancer genes and mutational processes operating, and progresses towards a comprehensive account of the somatic genetic basis of breast cancer.

A Randomized Phase II Study of Sequential Eribulin Versus Paclitaxel Followed by FAC/FEC as Neoadjuvant Therapy in Patients with Operable HER2-Negative Breast Cancer.

LESSONS LEARNED: The combination of eribulin with 5-fluorouracil, either doxorubicin or epirubicin, and cyclophosphamide (FAC/FEC) was not superior to the combination of paclitaxel with FAC/FEC and was associated with greater hematologic toxicity. Eribulin followed by an anthracycline-based regimen is not recommended as a standard neoadjuvant therapy in nonmetastatic operable breast cancer. BACKGROUND: Neoadjuvant systemic therapy is the standard of care for locally advanced operable breast cancer. We hypothesized eribulin may improve the pathological complete response (pCR) rate compared with paclitaxel. METHODS: We conducted a 1:1 randomized open-label phase II study comparing eribulin versus paclitaxel followed by 5-fluorouracil, either doxorubicin or epirubicin, and cyclophosphamide (FAC/FEC) in patients with operable HER2-negative breast cancer. pCR and toxicity of paclitaxel 80 mg/m2 weekly for 12 doses or eribulin 1.4 mg/m2 on days 1 and 8 of a 21-day cycle for 4 cycles followed by FAC/FEC were compared. RESULTS: At the interim futility analysis, in March 2015, 51 patients (28 paclitaxel, 23 eribulin) had received at least one dose of the study drug and were thus evaluable for toxicity; of these, 47 (26 paclitaxel, 21 eribulin) had undergone surgery and were thus evaluable for efficacy. Seven of 26 (27%) in the paclitaxel group and 1 of 21 (5%) in the eribulin group achieved a pCR, and this result crossed a futility stopping boundary. In the paclitaxel group, the most common serious adverse events (SAEs) were neutropenic fever (grade 3, 3 patients, 11%). In the eribulin group, nine patients (39%) had neutropenia-related SAEs, and one died of neutropenic sepsis. The study was thus discontinued. For the paclitaxel and eribulin groups, the 5-year event-free survival (EFS) rates were 81.8% and 74.0% (hazard ratio [HR], 1.549; 95% confidence interval [CI], 0.817-2.938; p = .3767), and the 5-year overall survival (OS) rates were 100% and 84.4% (HR, 5.813; 95% CI, 0.647-52.208; p = .0752), respectively. CONCLUSION: We did not observe a higher proportion of patients undergoing breast conservation surgery in the eribulin group than in the paclitaxel group. The patients treated with eribulin were more likely to undergo mastectomy and less likely to undergo breast conservation surgery, but the difference was not statistically significant. As neoadjuvant therapy for operable HER2-negative breast cancer, eribulin followed by FAC/FEC is not superior to paclitaxel followed by FAC/FEC and is associated with a higher incidence of neutropenia-related serious adverse events.

Nonphosphorylatable PEA15 mutant inhibits epithelial-mesenchymal transition in triple-negative breast cancer partly through the regulation of IL-8 expression.

BACKGROUND: Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype that lacks targeted therapies. Patients with TNBC have a very poor prognosis because the disease often metastasizes. New treatment approaches addressing drivers of metastasis and tumor growth are crucial to improving patient outcomes. Developing targeted gene therapy is thus a high priority for TNBC patients. PEA15 (phosphoprotein enriched in astrocytes, 15 kDa) is known to bind to ERK, preventing ERK from being translocated to the nucleus and hence blocking its activity. The biological function of PEA15 is tightly regulated by its phosphorylation at Ser104 and Ser116. However, the function and impact of phosphorylation status of PEA15 in the regulation of TNBC metastasis and in epithelial-to-mesenchymal transition (EMT) are not well understood. METHODS: We established stable cell lines overexpressing nonphosphorylatable (PEA15-AA) and phospho-mimetic (PEA15-DD) mutants. To dissect specific cellular mechanisms regulated by PEA15 phosphorylation status, we performed RT-PCR immune and metastasis arrays. In vivo mouse models were used to determine the effects of PEA15 phosphorylation on tumor growth and metastasis. RESULTS: We found that the nonphosphorylatable mutant PEA15-AA prevented formation of mammospheres and expression of EMT markers in vitro and decreased tumor growth and lung metastasis in in vivo experiments when compared to control, PEA15-WT and phosphomimetic PEA15-DD. However, phosphomimetic mutant PEA15-DD promoted migration, mesenchymal marker expression, tumorigenesis, and lung metastasis in the mouse model. PEA15-AA-mediated inhibition of breast cancer cell migratory capacity and tumorigenesis was the partial result of decreased expression of interleukin-8 (IL-8). Further, we identified that expression of IL-8 was possibly mediated through one of the ERK downstream molecules, Ets-1. CONCLUSIONS: Our results show that PEA15 phosphorylation status serves as an important regulator for PEA15's dual role as an oncogene or tumor suppressor and support the potential of PEA15-AA as a therapeutic strategy for treatment of TNBC.

Prospective Registry Trial Assessing the Use of Magnetic Seeds to Locate Clipped Nodes After Neoadjuvant Chemotherapy for Breast Cancer Patients.

BACKGROUND: Targeted axillary dissection (TAD) involves locating and removing both clipped nodes and sentinel nodes for assessment of the axillary response to neoadjuvant chemotherapy (NAC) by clinically node-positive breast cancer patients. Initial reports described radioactive seeds used for localization, which makes the technique difficult to implement in some settings. This trial was performed to determine whether magnetic seeds can be used to locate clipped axillary lymph nodes for removal. METHODS: This prospective registry trial enrolled patients who had biopsy-proven node-positive disease with a clip placed in the node and treatment with NAC. A magnetic seed was placed under ultrasound guidance in the clipped node after NAC. All the patients underwent TAD. RESULTS: Magnetic seeds were placed in 50 patients by 17 breast radiologists. All the patients had successful seed placement at the first attempt (mean time for localization was 6.1 min; range 1-30 min). The final position of the magnetic seed was within the node (n = 44, 88%), in the cortex (n = 3, 6%), less than 3 mm from the node (n = 2, 4%), or by the clip when the node could not be adequately visualized (n = 1, 2%). The magnetic seed was retrieved at surgery from all the patients. In 49 (98%) of the 50 cases, the clip and magnetic seed were retrieved from the same node. Surgeons rated the transcutaneous and intraoperative localization as easy for 43 (86%) of the 50 cases. No device-related adverse events occurred. CONCLUSIONS: Localization and selective removal of clipped nodes can be accomplished safely and effectively using magnetic seeds.

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.

Prognostic Value of HER2 to CEP17 Ratio on Fluorescence In Situ Hybridization Ratio in Patients with Nonmetastatic HER2-Positive Inflammatory and Noninflammatory Breast Cancer Treated with Neoadjuvant Chemotherapy with or without Trastuzumab.

BACKGROUND: We previously reported that in patients with HER2-positive (HER2+) locally advanced breast cancer treated with neoadjuvant trastuzumab-containing regimens, high HER2 to centromere enumerator probe 17 ratio on fluorescence in situ hybridization (HER2 FISH ratio) was an independent predictor of high pathologic complete response (pCR) rate, which translated into improved recurrence-free survival (RFS). We sought to determine whether high HER2 FISH ratio is a predictor of pCR and prognosis in patients with HER2+ nonmetastatic inflammatory breast cancer (IBC) and non-IBC treated with neoadjuvant chemotherapy with or without trastuzumab. MATERIALS AND METHODS: This study included all patients with histologically proven stage III, HER2+ primary IBC, and non-IBC treated with neoadjuvant chemotherapy with or without trastuzumab and definitive surgery during 1999-2012. Univariate and multivariate logistic regression models were applied to assess the effect of covariates on pCR. Kaplan-Meier estimates with log-rank test were employed for survival analysis. Univariate and multivariate Cox proportional hazards models were used to assess the effect of covariates on RFS and overall survival (OS). RESULTS: The study included 555 patients with stage III, HER+ breast cancer, 181 patients with IBC, and 374 with non-IBC. In the IBC cohort, HER2 FISH ratio was not significantly associated with pCR, RFS, or OS. In the non-IBC cohort, higher HER2 FISH ratio was significantly associated with higher pCR rate and longer OS. CONCLUSION: HER2 FISH ratio showed prognostic value among patients with HER2+ non-IBC but not HER2+ IBC treated with neoadjuvant chemotherapy. This disparity may be due to the underlying aggressive nature of IBC. IMPLICATIONS FOR PRACTICE: The findings of this study indicate that the HER2 to fluorescence in situ hybridization ratio as a continuous variable has promise as a predictor of pathologic complete response to neoadjuvant chemotherapy in patients with HER2-positive (HER2+) noninflammatory breast cancer (non-IBC) regardless of the results on HER2 immunohistochemical testing. In the future, some patients with HER2+ non-IBC and a high HER2 FISH ratio might even be offered personalized treatment options, such as nonsurgical treatment.

Distinguishing Non-Small Cell Lung Cancer Subtypes in Fine Needle Aspiration Biopsies by Desorption Electrospray Ionization Mass Spectrometry Imaging.

BACKGROUND: Distinguishing adenocarcinoma and squamous cell carcinoma subtypes of non-small cell lung cancers is critical to patient care. Preoperative minimally-invasive biopsy techniques, such as fine needle aspiration (FNA), are increasingly used for lung cancer diagnosis and subtyping. Yet, histologic distinction of lung cancer subtypes in FNA material can be challenging. Here, we evaluated the usefulness of desorption electrospray ionization mass spectrometry imaging (DESI-MSI) to diagnose and differentiate lung cancer subtypes in tissues and FNA samples. METHODS: DESI-MSI was used to analyze 22 normal, 26 adenocarcinoma, and 25 squamous cell carcinoma lung tissues. Mass spectra obtained from the tissue sections were used to generate and validate statistical classifiers for lung cancer diagnosis and subtyping. Classifiers were then tested on DESI-MSI data collected from 16 clinical FNA samples prospectively collected from 8 patients undergoing interventional radiology guided FNA. RESULTS: Various metabolites and lipid species were detected in the mass spectra obtained from lung tissues. The classifiers generated from tissue sections yielded 100% accuracy, 100% sensitivity, and 100% specificity for lung cancer diagnosis, and 73.5% accuracy for lung cancer subtyping for the training set of tissues, per-patient. On the validation set of tissues, 100% accuracy for lung cancer diagnosis and 94.1% accuracy for lung cancer subtyping were achieved. When tested on the FNA samples, 100% diagnostic accuracy and 87.5% accuracy on subtyping were achieved per-slide. CONCLUSIONS: DESI-MSI can be useful as an ancillary technique to conventional cytopathology for diagnosis and subtyping of non-small cell lung cancers.

Quantitative hormone receptor (HR) expression and gene expression analysis in HR+ inflammatory breast cancer (IBC) vs non-IBC.

BACKGROUND: The purpose of this study was to determine the prognostic role of hormone receptor (HR) on inflammatory breast cancer (IBC) to elucidate its aggressive biological behavior. METHODS: We evaluated the expression of estrogen receptor (ER) and progesterone receptor (PR) by immunohistochemical staining and determined the predictive and prognostic role of HR expression on 189 patients with HR+/HER2- IBC and 677 patients with HR+/HER2- stage III non-IBC. Furthermore, we performed gene expression (GE) analyses on 137 patients with HR+/HER2- IBC and 252 patients with HR+/HER2- non-IBC to detect genes that are specifically overexpressed in IBC. RESULTS: The expression of ER% was significantly associated with longer distant disease-free survival and overall survival. However, there was no significant relationship between ER% and neoadjuvant chemotherapy outcome. In the GE study, 84 genes were identified as significantly distinguishing HR+ IBC from non-IBC. Among the top 15 canonical pathways expressed in IBC, the ERK/MAPK, PDGF, insulin receptor, and IL-7 signaling pathways were associated with the ER signaling pathway. Upregulation of the MYC gene was observed in three of these four pathways. Furthermore, HR+/HER2- IBC had significantly higher MYC amplification, and the genetic alteration was associated with poor survival outcome. CONCLUSIONS: Higher ER expression was significantly associated with improved survival in both HR+/HER2- IBC and HR+/HER2- stage III non-IBC patients. HR+/HER2- IBC had several activated pathways with MYC upregulation, and the genetic alteration was associated with poor survival outcome. The results indicate that MYC may be a key gene for understanding the biology of HR+/HER2- IBC.

In vitro vascularized tumor platform for modeling tumor-vasculature interactions of inflammatory breast cancer.

Inflammatory breast cancer (IBC), a rare form of breast cancer associated with increased angiogenesis and metastasis, is largely driven by tumor-stromal interactions with the vasculature and the extracellular matrix (ECM). However, there is currently a lack of understanding of the role these interactions play in initiation and progression of the disease. In this study, we developed the first three-dimensional, in vitro, vascularized, microfluidic IBC platform to quantify the spatial and temporal dynamics of tumor-vasculature and tumor-ECM interactions specific to IBC. Platforms consisting of collagen type 1 ECM with an endothelialized blood vessel were cultured with IBC cells, MDA-IBC3 (HER2+) or SUM149 (triple negative), and for comparison to non-IBC cells, MDA-MB-231 (triple negative). Acellular collagen platforms with endothelialized blood vessels served as controls. SUM149 and MDA-MB-231 platforms exhibited a significantly (p < .05) higher vessel permeability and decreased endothelial coverage of the vessel lumen compared to the control. Both IBC platforms, MDA-IBC3 and SUM149, expressed higher levels of vascular endothelial growth factor (p < .05) and increased collagen ECM porosity compared to non-IBCMDA-MB-231 (p < .05) and control (p < .01) platforms. Additionally, unique to the MDA-IBC3 platform, we observed progressive sprouting of the endothelium over time resulting in viable vessels with lumen. The newly sprouted vessels encircled clusters of MDA-IBC3 cells replicating a key feature of in vivo IBC. The IBC in vitro vascularized platforms introduced in this study model well-described in vivo and clinical IBC phenotypes and provide an adaptable, high throughput tool for systematically and quantitatively investigating tumor-stromal mechanisms and dynamics of tumor progression.

Implementation of a Multiplex and Quantitative Proteomics Platform for Assessing Protein Lysates Using DNA-Barcoded Antibodies.

Molecular analysis of tumors forms the basis for personalized cancer medicine and increasingly guides patient selection for targeted therapy. Future opportunities for personalized medicine are highlighted by the measurement of protein expression levels via immunohistochemistry, protein arrays, and other approaches; however, sample type, sample quantity, batch effects, and "time to result" are limiting factors for clinical application. Here, we present a development pipeline for a novel multiplexed DNA-labeled antibody platform which digitally quantifies protein expression from lysate samples. We implemented a rigorous validation process for each antibody and show that the platform is amenable to multiple protocols covering nitrocellulose and plate-based methods. Results are highly reproducible across technical and biological replicates, and there are no observed "batch effects" which are common for most multiplex molecular assays. Tests from basal and perturbed cancer cell lines indicate that this platform is comparable to orthogonal proteomic assays such as Reverse-Phase Protein Array, and applicable to measuring the pharmacodynamic effects of clinically-relevant cancer therapeutics. Furthermore, we demonstrate the potential clinical utility of the platform with protein profiling from breast cancer patient samples to identify molecular subtypes. Together, these findings highlight the potential of this platform for enhancing our understanding of cancer biology in a clinical translation setting.

Thyroid carcinoma metastasizing to the submandibular gland: Sonographic findings.

Metastases to the submandibular gland are extremely rare; a literature search retuned only three previously reported cases from a thyroid gland primary site. Herein, we report two cases of metastatic thyroid carcinoma to the submandibular gland in a 64-year-old woman with PTC and a 70-year-old-woman with medullary thyroid carcinoma (MTC). The metastases were identified on CT and PET/CT in one case and on CT in the other case, but both were diagnosed with ultrasound-guided fine-needle aspiration. Our cases highlight that while rare, both PTC and MTC can metastasize to the submandibular gland.