Spatial Transcriptomics Suggests That Alterations Occur in the Preneoplastic Breast Microenvironment of BRCA1/2 Mutation Carriers.

Breast cancer is the most common cancer in females, affecting one in every eight women and accounting for the majority of cancer-related deaths in women worldwide. Germline mutations in the BRCA1 and BRCA2 genes are significant risk factors for specific subtypes of breast cancer. BRCA1 mutations are associated with basal-like breast cancers, whereas BRCA2 mutations are associated with luminal-like disease. Defects in mammary epithelial cell differentiation have been previously recognized in germline BRCA1/2 mutation carriers even before cancer incidence. However, the underlying mechanism is largely unknown. Here, we employ spatial transcriptomics to investigate defects in mammary epithelial cell differentiation accompanied by distinct microenvironmental alterations in preneoplastic breast tissues from BRCA1/2 mutation carriers and normal breast tissues from noncarrier controls. We uncovered spatially defined receptor-ligand interactions in these tissues for the investigation of autocrine and paracrine signaling. We discovered that ß1-integrin-mediated autocrine signaling in BRCA2-deficient mammary epithelial cells may differ from BRCA1-deficient mammary epithelial cells. In addition, we found that the epithelial-to-stromal paracrine signaling in the breast tissues of BRCA1/2 mutation carriers is greater than in control tissues. More integrin-ligand pairs were differentially correlated in BRCA1/2-mutant breast tissues than noncarrier breast tissues with more integrin receptor-expressing stromal cells. IMPLICATIONS: These results suggest alterations in the communication between mammary epithelial cells and the microenvironment in BRCA1 and BRCA2 mutation carriers, laying the foundation for designing innovative breast cancer chemo-prevention strategies for high-risk patients.

Alterations in the preneoplastic breast microenvironment of BRCA1/2 mutation carriers revealed by spatial transcriptomics.

Breast cancer is the most common cancer in females, affecting one in every eight women and accounting for the majority of cancer-related deaths in women worldwide. Germline mutations in the BRCA1 and BRCA2 genes are significant risk factors for specific subtypes of breast cancer. BRCA1 mutations are associated with basal-like breast cancers, whereas BRCA2 mutations are associated with luminal-like disease. There are currently few chemoprevention strategies available for BRCA1/2 mutation carriers, and irreversible prophylactic mastectomy is the primary option. Designing chemo-preventive strategies requires an in-depth understanding of the physiological processes underlying tumor initiation. Here, we employ spatial transcriptomics to investigate defects in mammary epithelial cell differentiation accompanied by distinct microenvironmental alterations in preneoplastic breast tissues from BRCA1/2 mutation carriers and normal breast tissues from non-carrier controls. We uncovered spatially defined receptor-ligand interactions in these tissues for the investigation of autocrine and paracrine signaling. We discovered that ß1-integrin-mediated autocrine signaling in BRCA2-deficient mammary epithelial cells differs from BRCA1-deficient mammary epithelial cells. In addition, we found that the epithelial-to-stromal paracrine signaling in the breast tissues of BRCA1/2 mutation carriers is greater than in control tissues. More integrin-ligand pairs were differentially correlated in BRCA1/2-mutant breast tissues than non-carrier breast tissues with more integrin receptor-expressing stromal cells. These results reveal alterations in the communication between mammary epithelial cells and the microenvironment in BRCA1 and BRCA2 mutation carriers, laying the foundation for designing innovative breast cancer chemo-prevention strategies for high-risk patients.

Re-Classification with Outcome Correlation of Previously Diagnosed Malignant Phyllodes Tumors Applying the 2016 Consensus Guidelines.

Background. Classification of phyllodes tumors is challenging due unclear diagnostic criteria, recently addressed by consensus review criteria. Herein, we reviewed all malignant phyllodes tumor resections and reclassified them based on the consensus guidelines, correlating with outcome. We hypothesize that application of criteria would result in a significant proportion being "down-graded" to either borderline or benign phyllodes tumor. Methods. Primary resections of malignant phyllodes tumor were reviewed by four AP board-certified, breast fellowship-trained pathologists. Morphologic variables delineated in consensus guidelines (ie stromal cellularity, cellular atypia, tumor border, presence of heterologous elements, presence of stromal overgrowth) were evaluated. Following review, cases were reclassified as benign, borderline, or malignant. Results. Upon reclassification, 20% (5/20) cases were "down-graded" to borderline phyllodes tumor while 80% (15/20) remained malignant phyllodes tumor. Two morphologic features were statistically significant including broadly infiltrating tumor border in 80% (12/15) of malignant phyllodes tumors compared to none in borderline phyllodes tumor (0/5) (p = 0.004) and stromal overgrowth in 67% (10/15) of malignant phyllodes tumor compared to none in borderline phyllodes tumors (0/5) (p = 0.03). Upon review of the pathology reports, 30% (6/20) contained all 5 histomorphologic variables delineated in the consensus review criteria. Malignant phyllodes tumor resulted in five cases with recurrence (33.3%, 5/15) and three cases with metastases (20.0%, 3/15) and borderline phyllodes tumor resulted in one case with recurrence (20.0%, 1/5) and no metastases (0/5). Conclusion. The consensus guidelines for phyllodes tumor are useful for subclassification. We hypothesize that standardize reporting of the histomorphologic variables may lead to better consensus.

Two Instrument Comparison of Reagents From a US FDA-Approved Assay for the Assessment of Ki-67 in High-Risk Early Breast Cancer.

The objective of this study was to measure concordance of results obtained from the US Food and Drug Administration-approved Ki-67 immunohistochemistry MIB-1 pharmDx assay performed on the Dako Omnis automated staining instrument (Omnis) versus results produced from the assay reagents applied using an optimized protocol on the more widely available Autostainer Link 48 (ASL48) platform. Tissue sections obtained from 40 formalin-fixed paraffin-embedded breast carcinoma samples, with available Oncotype DX Breast Recurrence Score (RS) results, were stained. Three certified pathologists scored slides at 3 timepoints, totaling 360 observations for each instrument (N=720 total) using the approved scoring approach. Using the ≥20% cutoff, agreement was calculated with corresponding 2-sided 95% percentile bootstrap confidence intervals (CIs). Pairwise comparisons (N=360) from the interinstrument evaluation, performed with all observers, resulted in 325 (90.3%) concordant outcomes (244 negative and 81 positive) and 35 (9.7%) discordant outcomes. The overall agreement was 90.3% (95% confidence interval, 85.6% to 94.4%). No significant systematic differences were observed between instruments. Specimens scored from the Omnis were on average <1% higher than ASL48, with high correlation and little bias between the continuous Ki-67 scores (concordance correlation coefficient=0.916). Most specimens with a Ki-67 score ≥20% had a RS >25. This study demonstrated that good concordance can be achieved with the reagents run on the ASL48 instrument when using an optimized protocol and standardized scoring.

Clinical and Pathologic Features Associated With Invasive Breast Carcinoma With 2018 American Society of Clinical Oncology/College of American Pathologists In Situ Hybridization Group 2 Results (Human Epidermal Growth Factor Receptor 2 [HER2]/Chromosome 17 Centromere [CEP17] Ratio ≥2.0 and Average HER2 Copy Number <4.0).

CONTEXT.­: The American Society of Clinical Oncology/College of American Pathologists updated the human epidermal growth factor receptor 2 (HER2) breast carcinoma testing guideline in 2018 to address issues from uncommon HER2 fluorescence in situ hybridization (FISH) results. Based on the 2013 American Society of Clinical Oncology/College of American Pathologists guideline, cases wherein the HER2/chromosome 17 centromere (CEP17) ratio of 2.0 or more with an average HER2 copy number of less than 4.0 were considered in situ hybridization (ISH) positive. Under the 2018 guideline, such cases are classified as ISH Group 2 and are no longer considered eligible for anti-HER2 therapy when the corresponding HER2 immunohistochemistry result is 0, 1+, or 2+. OBJECTIVE.­: To assess the clinical, pathologic, and treatment aspects of patients with ISH Group 2 results. DESIGN.­: We retrospectively reviewed HER2 FISH results at our center between January 2012 and December 2014 and identified and characterized cases with ISH Group 2 results. RESULTS.­: Thirty-nine cases with ISH Group 2 results from 39 patients were reviewed. Twenty of 39 (51%) patients received anti-HER2 therapy. Patients treated with HER2-targeted therapy were less likely to have hormone receptor-positive tumors, compared with patients without anti-HER2 treatment, though not significantly (P = .30). The only significant difference between the 2 patient groups was receipt of cytotoxic chemotherapy treatment (P < .001). Overall, clinical outcome was similar between the 2 groups (P > .99). CONCLUSIONS.­: This retrospective study with median follow-up of at least 6 years shows patients with ISH Group 2 tumors had similar clinical outcomes, irrespective of HER2-targeted therapy. Further analysis in the prospective setting would provide valuable data that would potentially inform clinical decision making.

The 21-Gene Recurrence Score in Special Histologic Subtypes of Breast Cancer.

CONTEXT.­: Recurrence score (RS) testing was developed and validated in invasive ductal and rare lobular carcinomas, although it is used for all special types of breast cancers. OBJECTIVE.­: To determine association of histologic type (HT) and RS, specifically high-risk RS. DESIGN.­: We used RSs linked to Surveillance, Epidemiology, and End Results Program registries of invasive breast cancers diagnosed in 2004 through 2015. Multivariable logistic regression was used to evaluate association between HT and high-risk RS. Relationships between HT and low-, intermediate-, and high-risk RS were compared with χ2 test. Kaplan-Meier curves were compared using log-rank test. RESULTS.­: A total of 110 318 patients had RS testing. Of these, 23 220 (21%) had low, 70 822 (64.2%) intermediate, and 16 276 (14.8%) high RS. Histologic types were 80 476 (73%) ductal, 12 713 (11.5%) lobular, 12 449 (11.3%) mixed, 2151 (2%) mucinous, 610 (0.6%) tubular, 382 (0.4%) micropapillary, 365 (0.3%) salivary, 208 (0.2%) papillary, 49 (0.04%) medullary, 26 (0.02%) metaplastic, 26 (0.02%) neuroendocrine, and 863 (0.8%) unknown. The distribution of low-, intermediate-, and high-risk RS was significantly different among HTs. Higher percentages of high-risk RS were identified in patients with ductal, medullary, and metaplastic types (P < .001). The odds of having high-risk RS were lower for some HTs, including micropapillary, after multivariable adjustment (P < .05). The low number of estrogen receptor-positive medullary and metaplastic carcinomas tested had higher odds of having high-risk RS. In T1 and T2 tumors, when ductal, lobular, mixed, and other types combined were compared, the mortality was different. CONCLUSIONS.­: This population-based study of RS in HTs showed high-risk RSs are identified in traditionally good prognostic subtypes. Micropapillary carcinoma has lower odds of high-risk RS even after multivariable adjustment.

Outcomes of ipsilateral breast tumor recurrence after breast conserving surgery: Repeat lumpectomy as an alternative to salvage mastectomy.

BACKGROUND: We examined the outcomes of salvage mastectomy and repeat lumpectomy for management of ipsilateral breast tumor recurrence. METHODS: Between 2013 and 2019, 113 patients with an ipsilateral breast tumor recurrence after breast conserving surgery were identified. Patients and tumor characteristics at initial diagnosis and at recurrence were collected. Outcomes evaluated included second recurrence and overall survival. Complications at 30-days and 90-days after surgery for ipsilateral breast tumor recurrence were evaluated. RESULTS: Seventy-two percent of patients underwent salvage mastectomy (n = 84) and 28% underwent repeat lumpectomy (n = 32 overall, n = 13 reirradiation). Salvage mastectomy patients were younger at initial diagnosis (P = .007) with longer time to ipsilateral breast tumor recurrence from first diagnosis (P = .03). At 2.5 years median follow-up, the overall incidence of second recurrence was 8% with 5% rate (n = 4) in salvage mastectomy group versus 16% (n = 5) in repeat lumpectomy group; however, among patients undergoing repeat lumpectomy with reirradiation (n = 13), only one patient developed a second recurrence (8%). There was no significant difference in rates of second local recurrence (P = .11), disease free survival (P = .13), or overall survival (P = .95) between repeat lumpectomy with reirradiation and salvage mastectomy. CONCLUSION: At a short-term follow-up, repeat lumpectomy with reirradiation could be considered in a select group of patients presenting with an ipsilateral breast tumor recurrence with multidisciplinary input with low rates of postoperative complications and equivalent survival outcomes.

Novel temporal and spatial patterns of metastatic colonization from breast cancer rapid-autopsy tumor biopsies.

BACKGROUND: Metastatic breast cancer is a deadly disease with a low 5-year survival rate. Tracking metastatic spread in living patients is difficult and thus poorly understood. METHODS: Via rapid autopsy, we have collected 30 tumor samples over 3 timepoints and across 8 organs from a triple-negative metastatic breast cancer patient. The large number of sites sampled, together with deep whole-genome sequencing and advanced computational analysis, allowed us to comprehensively reconstruct the tumor's evolution at subclonal resolution. RESULTS: The most unique, previously unreported aspect of the tumor's evolution that we observed in this patient was the presence of "subclone incubators," defined as metastatic sites where substantial tumor evolution occurs before colonization of additional sites and organs by subclones that initially evolved at the incubator site. Overall, we identified four discrete waves of metastatic expansions, each of which resulted in a number of new, genetically similar metastasis sites that also enriched for particular organs (e.g., abdominal vs bone and brain). The lung played a critical role in facilitating metastatic spread in this patient: the lung was the first site of metastatic escape from the primary breast lesion, subclones at this site were likely the source of all four subsequent metastatic waves, and multiple sites in the lung acted as subclone incubators. Finally, functional annotation revealed that many known drivers or metastasis-promoting tumor mutations in this patient were shared by some, but not all metastatic sites, highlighting the need for more comprehensive surveys of a patient's metastases for effective clinical intervention. CONCLUSIONS: Our analysis revealed the presence of substantial tumor evolution at metastatic incubator sites in a patient, with potentially important clinical implications. Our study demonstrated that sampling of a large number of metastatic sites affords unprecedented detail for studying metastatic evolution.

HER2 Testing: Insights From Pathologists' Perspective on Technically Challenging HER2 FISH Cases.

OBJECTIVE: College of American Pathologists and the American Society of Clinical Oncology guidelines provide straightforward criteria for HER2 interpretation in breast carcinomas; however, a subset of cases present unusual diagnostic dilemmas. MATERIALS AND METHODS: Ten challenging HER2 fluorescence in situ hybridization (FISH) cases were selected for analysis. The study included a variety of problematic cases such as those with discordant immunohistochemistry (IHC) and FISH results, cases with high intratumoral variability in HER2 copy number, a case with a highly amplified clone in 5% to 10% of the tumor sample, and a case with tumor cells containing tightly clumped HER2 signals. Six high volume HER2 FISH laboratories performed and interpreted HER2 FISH (adding HER2 IHC if necessary). Interpretation strategies were discussed. RESULTS: There was 100% concordance between laboratories in 4/10 cases. Tumors with increased intratumoral variability (tumors with high variability in HER2 copy number per cell but which otherwise do not fulfill College of American Pathologists and the American Society of Clinical Oncology criteria for heterogeneity) exhibited 100% concordance in 3/4 cases, but 1 case had only 50% agreement. Low positive HER2 cases (group 1 cases with <6 average HER2 copies/cell) had 1 laboratory disagreeing with the majority in 4/4 cases, and this was the only category with discordance between IHC and FISH methodologies. All laboratories identified the case with heterogeneity and interpreted it as positive. Five of the 6 laboratories interpreted the case with tightly clustered HER2 signals as positive. CONCLUSIONS: This study offers specific observations and interpretation strategies that laboratories can use when confronted with difficult HER 2 cases. It then highlights communication strategies a laboratory may use to discuss these unusual HER2 results with the clinical team.

Human breast microbiome correlates with prognostic features and immunological signatures in breast cancer.

BACKGROUND: Currently, over half of breast cancer cases are unrelated to known risk factors, highlighting the importance of discovering other cancer-promoting factors. Since crosstalk between gut microbes and host immunity contributes to many diseases, we hypothesized that similar interactions could occur between the recently described breast microbiome and local immune responses to influence breast cancer pathogenesis. METHODS: Using 16S rRNA gene sequencing, we characterized the microbiome of human breast tissue in a total of 221 patients with breast cancer, 18 individuals predisposed to breast cancer, and 69 controls. We performed bioinformatic analyses using a DADA2-based pipeline and applied linear models with White's t or Kruskal-Wallis H-tests with Benjamini-Hochberg multiple testing correction to identify taxonomic groups associated with prognostic clinicopathologic features. We then used network analysis based on Spearman coefficients to correlate specific bacterial taxa with immunological data from NanoString gene expression and 65-plex cytokine assays. RESULTS: Multiple bacterial genera exhibited significant differences in relative abundance when stratifying by breast tissue type (tumor, tumor adjacent normal, high-risk, healthy control), cancer stage, grade, histologic subtype, receptor status, lymphovascular invasion, or node-positive status, even after adjusting for confounding variables. Microbiome-immune networks within the breast tended to be bacteria-centric, with sparse structure in tumors and more interconnected structure in benign tissues. Notably, Anaerococcus, Caulobacter, and Streptococcus, which were major bacterial hubs in benign tissue networks, were absent from cancer-associated tissue networks. In addition, Propionibacterium and Staphylococcus, which were depleted in tumors, showed negative associations with oncogenic immune features; Streptococcus and Propionibacterium also correlated positively with T-cell activation-related genes. CONCLUSIONS: This study, the largest to date comparing healthy versus cancer-associated breast microbiomes using fresh-frozen surgical specimens and immune correlates, provides insight into microbial profiles that correspond with prognostic clinicopathologic features in breast cancer. It additionally presents evidence for local microbial-immune interplay in breast cancer that merits further investigation and has preventative, diagnostic, and therapeutic potential.

Allaying uncertainty in diagnosing buried Barrett's esophagus.

Subsquamous intestinal metaplasia (SSIM) in the setting of Barrett's esophagus (BE) is a technically challenging diagnosis. While the risk for progression of BE involving the surface mucosa is well documented, the potential risk for development of advanced neoplasia associated with SSIM has been controversial. This study aimed to determine the effects of specimen adequacy, presence of dysplasia, and interobserver agreement for SSIM interpretation. Adult patients (n = 28) who underwent endoscopic therapy for BE with high-grade dysplasia or intramucosal carcinoma (HGD/IMC) between October 2005 and June 2013 were included. Initial evaluation (n = 140 slides) by an experienced gastrointestinal pathologist was followed by an interobserver study by 8 pathologists. Forty-seven (34%) slides had insufficient subsquamous tissue to assess for SSIM. SSIM was found in 19% of all slides and 29% of slides with sufficient subsquamous tissue. At least one slide had SSIM in 54% to 64% of patients. Subsquamous low grade dysplasia (LGD) was found in 4 (15%) slides with SSIM and subsquamous HGD/IMC was found in 5 (19%) slides with SSIM. At the patient level, 8 (53%) had no dysplasia, 4 (27%) had LGD and 3 (20%) had HGD/IMC. Overall agreement for SSIM by slide was 92% to 94% (κ = 0.73 to κ = 0.82, moderate to strong agreement), and by patient was 82% to 94% (κ = 0.65 to κ = 0.87, moderate to strong agreement). This study confirms the need for assessing specimen adequacy and assessing the prevalence of SSIM and is the first to assess interobserver agreement for SSIM and dysplasia within SSIM.

Amyloid in the breast: retrospective review with clinicopathological and radiological correlation of 32 cases from a single institution.

AIMS: Mammary amyloid is an uncommon and easily overlooked pathological diagnosis with ambivalent presentation. Herein, we delineate the clinicopathological and radiographic characteristics of mammary amyloid. METHODS AND RESULTS: The Department of Pathology database was searched from 1993 to 2019 for keywords 'breast' and 'amyloid', yielding 32 cases from 23 patients, including consultation cases. All patients were female, age range = 52-81 (mean = 67.4 years). The left breast was involved more than the right (43 versus 33%, respectively); bilateral amyloid involvement was also present (24%). Amyloid was most often associated with a benign histopathological diagnosis (57%), lymphoma in 39% [all B cell lymphomas; five of nine were mucosa-associated lymphoid tissue (MALT) lymphoma] and rarely with a concurrent epithelial malignancy (invasive lobular carcinoma, 4%). Of the 14 patients with available clinical history, amyloid presented as a mass clinically or radiographically (six patients, 43%), as microcalcifications (five patients, 36%), and only occasionally as an asymmetry (14%) or fibroglandular density (7%). Microscopic examination detected microcalcifications in an additional nine cases (total 14 patients; 44% of the cohort). Interestingly, one patient had concurrent epithelial and haematological malignancy and amyloid within an axillary lymph node. Co-morbidities included autoimmune diseases and multiple myeloma. CONCLUSION: The majority of mammary amyloid cases are associated with benign histopathological findings, while imaging most frequently noted microcalcifications or mass lesions. To avoid overlooking amyloid as simply fat necrosis or fibroelastotic stromal change, a low threshold for performing ancillary stains should be considered in elderly women with benign core needle findings performed for mass lesions or microcalcifications.

Mammary Extranodal Rosai-Dorfman Disease With and Without Associated Axillary Lymphadenopathy: Insights for Practitioners of Breast Pathology.

Rosai-Dorfman disease is a rare proliferative histiocytic disorder of lymph nodes that is descriptively known as sinus histiocytosis with massive lymphadenopathy. Extranodal involvement of the parenchyma of the breast is uncommonly reported, with fewer than 50 cases of mammary extranodal disease detailed in the English-language literature. We characterize a retrospective series of adult female patients from a single institution with Rosai-Dorfman disease of the breast and axillary lymph nodes. Because Rosai-Dorfman disease of the breast and axillary lymph nodes may clinically, radiographically, and histologically mimic breast carcinoma and other conditions, we present an illustrated review of the disease and its relevant differential diagnoses in hopes of raising awareness and allowing for accurate management of affected patients.

Specific Histopathologic Features Aid in Distinguishing Diffuse-type Gastric Adenocarcinoma From Metastatic Lobular Breast Carcinoma.

Metastatic invasive lobular carcinoma (mILC) may masquerade as primary diffuse gastric adenocarcinoma (PDGA) by demonstrating significant clinical and pathologic overlap. Accurate distinction is of therapeutic and prognostic significance. On the basis of anecdotal cases of mILC that lacked estrogen receptor and/or GATA3 expression, we analyzed the cytoarchitectural features of 28 mILC and 44 PDGA specimens obtained from women to assess features that would help in this distinction and prompt ancillary work-up. In addition to performing an interobserver agreement analysis among 3 pathologists, we also evaluated SATB2 expression in this setting. Eighteen of 20 (90%) patients had a history of ILC. The mean interval between initial diagnosis of breast cancer and metastasis was 7.3 years (range: 1 to 36 y). Compared with mILC, PDGA was significantly associated with full-thickness mucosal involvement (47% vs. 80%; P=0.015), a nested/sheet-like growth pattern (32% vs. 68%; P=0.004), anastomosing cords (0% vs. 100%; P=0.001), multivacuolated cells (0% vs. 61%; P<0.0001), pleomorphic nuclei (4% vs. 70%; P<0.0001) and enlarged nuclei (4% vs. 70%; P<0.0001). Single file growth pattern (P<0.0001) and superficial lamina propria involvement (P=0.009) were more common in mILC. Estrogen receptor and GATA3 were expressed in all but 5 mILC cases; SATB2 was only seen in 30% of PDGA cases. Our results demonstrate that in a biopsy specimen, careful morphologic assessment can be extremely helpful in distinguishing mILC from PDGA and guiding ancillary work-up, especially when a history of breast cancer may not be readily available or when the neoplasm lacks expression of conventional breast markers.

Pancreatic metastases to the colon: an unusual cause of colonic obstruction.

We report a case of a 73-year-old woman who developed pancreatic adenocarcinoma and presented with a colonic obstruction due to isolated metastasis to the colon, the primary lesion being diagnosed subsequently on imaging. The histopathological findings of the pancreatic mass exhibited a morphology and immunohistochemical profile consistent with a pancreatic adenocarcinoma and led to further analysis of the colonic pathology which ultimately confirmed the lesion was a pancreatic metastases rather than a primary colonic carcinoma. As the pancreatic cancer had metastasised to the colon, it was inoperable. The patient continued on palliative chemotherapy and passed 7 months after presentation for evaluation of her pancreatic mass due to progression of the pancreatic cancer. This report demonstrates a rare presentation of pancreatic cancer with colonic obstruction due to isolated metastatic disease and illustrated the importance of careful evaluation of histopathological findings.

Mammary mesenchymal and fibroepithelial lesions: An illustrated cytomorphologic update with differential diagnoses.

The Uniform Approach to Breast Fine Needle Aspiration Biopsy was put forward by a learned group of breast physicians in 1997. This landmark manuscript focused predominantly on diagnosis and reporting of mammary epithelial lesions. Today, most American practitioners turn initially to core biopsy rather than aspiration biopsy for the first line diagnosis of solid breast lesions; however, recent efforts from the International Academy of Cytology have produced a system called the Standardized Reporting of Breast Fine Needle Aspiration Biopsy Cytology (colloquially labeled in 2017 as the "Yokohama System"), suggesting a new interest in breast fine needle aspiration (FNA), especially in resource limited settings or clinical practice settings with experienced breast cytopathologists. Fibroepithelial lesions of the breast comprise a heterogeneous group of biphasic tumors with epithelial and stromal elements. Mesenchymal lesions of the breast include a variety of neoplasms of fibroblastic, myofibroblastic, endothelial, neural, adipocytic, muscular, and osteo-cartilaginous derivations. The cytology of mesenchymal breast lesions is infrequently described in the literature and is mainly limited to case reports and small series. This illustrated review highlights the cytologic features of fibroepithelial and mesenchymal mammary proliferations and discusses differential diagnoses and histomorphologic correlates.

Elevated Tryptase in EoE Is an Independent Phenomenon Associated with Extra-Esophageal Symptoms.

BACKGROUND: Eosinophilic esophagitis (EoE) is a chronic disease characterized histologically by > 15 eosinophils per high-power field (eos/hpf). Esophageal mucosal mast cells have been implicated in EoE pathogenesis. The association of atopy with EoE has been established but has not been correlated with levels of serum tryptase. The lack of concurrent atopy in some patients suggests the possibility that atopy may either be the related subtype of EoE or may be a sign of comorbidities. No study has looked at whether patients present with different phenotypes/comorbid disease when they have evidence of elevated serum tryptase. We hypothesized that these patients differ with respect to presentation and comorbidities with more refractory GI disease. AIMS: To examine whether elevations of serum tryptase associate with different, more severe clinical presentations in EoE patients which may be explained via mast cell activation. MATERIALS AND METHODS: Retrospective chart review identified 72 patients with EoE with results for serum tryptase between 2015 and 2016. Patients were classified as TryptaseHI (tryptase > 10.9 µg/l) and TryptaseLO (< 10.9 µg/l). Clinical characteristics and treatment response were compared using univariate analysis and multivariate regression between the groups. RESULTS: Out of 72 patients, 12 were tested as TryptaseHI (16.7%, 95% CI 8.1-25.3%). TryptaseHI was associated frequently with asthma (P = 0.0003), urticaria (P = 0.002), arthralgia (P = 0.005), sinusitis (P = 0.03), nausea/vomiting (P = 0.046), and eosinophilic gastrointestinal disease (P = 0.001). Asthma and arthralgia were found to be significantly associated with TryptaseHI (P = 0.0013, P = 0.0098, respectively). Mucosal eosinophil counts and tryptase levels were not correlated (R2 0.095, P = 0.77). Tryptase did not resolve with resolution of esophageal eosinophilia. CONCLUSIONS: We found that EoE patients with elevated tryptase levels more commonly presented with asthma, urticaria, arthralgia, nausea/vomiting, sinusitis, and more distal eosinophilia. This indicates that atopy in EoE patients warrants further exploration. The lack of correlation between histologic remission and reduction of serum tryptase levels post-treatment suggests that mast cell activation may be an independent, yet associated disease. More study into this unique association is warranted.

Cystic neutrophilic granulomatous mastitis: The Cleveland Clinic experience with diagnosis and management.

Granulomatous mastitis is an uncommon inflammatory disease that typically presents with painful breast lesions. Recent publications have brought to light a specific subset of granulomatous mastitis patients with a distinct histological pattern of disease termed, "cystic neutrophilic granulomatous mastitis" (CNGM). Although many cases of granulomatous lobular mastitis have been thought to be idiopathic, this rare subset of an uncommon disease has been linked to infections with Corynebacterium species. Herein, a cohort of CNGM patients from a large, tertiary care, North-American, academic medical center is presented. Correlative demographic, clinical, radiographic, pathologic, microbiologic, management, and outcomes data are provided. Collaborative communication between specialists to accurately diagnose and manage these patients is essential to decreasing potential morbidity.

Secretory breast carcinoma in an 8-year-old girl: A case report and literature review.

Secretory breast carcinoma (SBC) is a rare form of breast cancer found in both children and adults, and is the most common breast cancer in the pediatric population. Although SBC usually carries a favorable prognosis, there have been reported cases of axillary and distant metastases. Surgery is the primary mode of treatment, however, there exists variability within the literature surrounding the management of SBC. We report a case of an 8-year-old girl who presented with a firm, mobile, palpable breast mass. Ultrasonography was performed, followed by local excision, with surgical pathology concerning for SBC. The patient was definitively treated with mastectomy and sentinel lymph node (SLN) biopsy. She received no adjuvant therapies and 2 years later, remains disease free. Herein, we review the literature, curate data from 89 reported cases of pediatric and adult SBC, and address some of the controversy surrounding its treatment. From this review we conclude that patients with SBC should be reviewed at multidisciplinary treatment planning conference, undergo surgery with mastectomy or lumpectomy with SLN biopsy, and have long-term postoperative follow-up.