Some pleomorphic adenomas of the breast share PLAG1 rearrangements with the analogous tumour of the salivary glands.

AIMS: Pleomorphic adenoma (PA) of the breast, and especially its malignant transformation, is extremely rare and represents a diagnostic pitfall. Molecular alterations in this entity have not been investigated. We aimed to examine the clinicopathological features of our breast PAs and perform molecular analysis. METHODS AND RESULTS: Seven cases of breast PA, including two cases of carcinoma ex PA, were analysed. PLAG1 and HMGA2 gene rearrangements were assayed by fluorescence in-situ hybridisation (FISH) and RNA sequencing (RNA-Seq), respectively. Reverse transcription-polymerase chain reaction (RT-PCR) and Sanger sequencing were used to verify RNA sequencing results. All seven cases of breast PA occurred in women. The histological features were similar to the analogous tumour in salivary glands, including a dual epithelial-myoepithelial component and negativity of oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) by immunohistochemistry. Of the two cases with carcinoma ex PA, one demonstrated minimal invasion and one was extensively invasive. PLAG1 rearrangements were identified in two cases (28.6%), but no rearrangements of HMG2A were found. A novel fusion product in PAs, TRPS1-PLAG1, was identified in one case. No patients had recurrence or metastasis with a follow-up period of 6-158 months. CONCLUSIONS: Breast PA is rare, but it is an important differential diagnosis of breast pathology with the potential to develop carcinoma ex PA. We report a novel TRPS1-PLAG1 fusion gene in breast PA.

Utilization of Health Care Resources by the Amish of a Rural County in Nebraska.

The medical needs of the New Order Amish (NOA) remain poorly understood. The NOA community in Pawnee County, Nebraska was founded in 2011 by members from across the Midwest. Understanding what this community wants from their medical providers informs how rural hospitals may best serve the needs of growing NOA populations. To address this, the current utilization of the closest healthcare resource to community were assessed. Medical records data for Amish patients were obtained at Pawnee County Memorial Hospital and Rural Health Clinic from 2011 to 2016. Subjective data were obtained by surveys and interviews administered to Amish in Pawnee County. The 422 complete interactions in the medical record covered most primary care complaints. The fifteen survey respondents valued direct interaction with providers and expressed concerns about cost, emergencies, and access to obstetric practice. Surprisingly, though surveys indicated minimal use of health establishments for many common health complaints, medical records indicated frequent doctor visits for myriad reasons. Naturalistic books were the most utilized source of health information. The NOA utilize formal medicine, but may feel excluded in medical decision-making. They desire better access to obstetric care and culturally sensitive medical practice. Providers should ensure appropriate communication to increase healthcare-related comfort of this underserved population.

Hb Gibbon [ß124(H2)Pro→Thr (HBB: c.373C>A, p.P125T)], an Asymptomatic Novel Hemoglobin Variant Detected by Newborn Screening.

We describe here a previously unreported hemoglobin (Hb) variant, Hb Gibbon [ß124(H2)Pro→Thr (HBB: c.373C>A, p.P125T)] detected by newborn Hb screening in a term male with no family history for hemoglobinopathy or other screening abnormalities. This missense mutation produces a ß-globin chain variant that was detected by high performance liquid chromatography (HPLC) methods, but is silent by capillary electrophoresis (CE). DNA sequencing studies revealed that his father was also a heterozygote for this mutation. Neither has abnormalities on complete blood count (CBC) or any symptomatology.

IDH2R172 mutations define a unique subgroup of patients with angioimmunoblastic T-cell lymphoma.

Angioimmunoblastic T-cell lymphoma (AITL) is a common subtype of peripheral T-cell lymphoma (PTCL) with a poor prognosis. We performed targeted resequencing on 92 cases of PTCL and identified frequent mutations affecting RHOA, TET2, DNMT3A, and isocitrate dehydrogenase 2 (IDH2). Although IDH2 mutations are largely confined to AITL, mutations of the other 3 can be found in other types of PTCL, although at lower frequencies. These findings indicate a key role of epigenetic regulation in the pathogenesis of AITL. However, the epigenetic alterations induced by these mutations and their role in AITL pathogenesis are still largely unknown. We correlated mutational status with gene expression and global DNA methylation changes in AITL. Strikingly, AITL cases with IDH2(R172) mutations demonstrated a distinct gene expression signature characterized by downregulation of genes associated with TH1 differentiation (eg, STAT1 and IFNG) and a striking enrichment of an interleukin 12-induced gene signature. Ectopic expression of IDH2(R172K) in the Jurkat cell line and CD4(+) T cells led to markedly increased levels of 2-hydroxyglutarate, histone-3 lysine methylation, and 5-methylcytosine and a decrease of 5-hydroxymethylcytosine. Correspondingly, clinical samples with IDH2 mutations displayed a prominent increase in H3K27me3 and DNA hypermethylation of gene promoters. Integrative analysis of gene expression and promoter methylation revealed recurrently hypermethylated genes involved in T-cell receptor signaling and T-cell differentiation that likely contribute to lymphomagenesis in AITL.

Global microRNA expression profiling uncovers molecular markers for classification and prognosis in aggressive B-cell lymphoma.

We studied the global microRNA (miRNA) expression in diffuse large B-cell lymphoma (DLBCL; n = 79), Burkitt lymphoma (BL; n = 36), primary mediastinal B-cell lymphoma (PMBL; n = 12), B-cell lines (n = 11), and normal subsets of naïve B cells, centroblasts (CBs), and peripheral blood B cells along with their corresponding gene expression profiles (GEPs). The normal B-cell subsets have well-defined miRNA signatures. The CB miRNA signature was significantly associated with germinal center B-cell (GCB)-DLBCL compared with activated B-cell (ABC)-DLBCL (P = .002). We identified a 27-miRNA signature that included v-myc avian myelomatosis viral oncogene homolog (MYC) targets and enabled the differentiation of BL from DLBCL, a distinction comparable with the "gold standard" GEP-defined diagnosis. Distinct miRNA signatures were identified for DLBCL subgroups, including GCB-DLBCL, activated B-cell (ABC)-DLBCL, and PMBL. Interestingly, most of the unclassifiable-DLBCL by GEP showed a strong similarity to the ABC-DLBCL by miRNA expression profiling. Consistent results for BL and DLBCL subgroup classification were observed in formalin-fixed, paraffin-embedded tissue, making such tests practical for clinical use. We also identified predictive miRNA biomarker signatures in DLBCL, including high expression of miR-155, which is significantly associated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) treatment failure. This finding was further supported by the observation that high expression of miR-155 sensitizes cells to v-akt murine thymoma viral oncogene homolog-1 inhibitors in vitro, suggesting a novel treatment option for resistant DLBCL.

Real-Time Telepathology Is Substantially Equivalent to In-Person Intraoperative Frozen Section Diagnosis.

CONTEXT.­: Intraoperative diagnosis by frozen section is a mainstay of surgical pathology practice, providing immediate feedback to the surgical team. Despite good accuracy with modern methods, access to intraoperative surgical pathology with an appropriate turnaround time (TAT) has been a limiting factor for small or remote surgical centers, with negative impacts on cost and patient care. Telepathology offers immediate expert anatomic pathology consultation to sites without an in-house or subspecialized pathologist. OBJECTIVE.­: To assess the utility of live telepathology in frozen section practice. DESIGN.­: Frozen section diagnoses by telemicroscopy from 2 tertiary care centers with a combined 3 satellite hospitals were queried for anatomic site, TAT per block, pathologist, and concordance with paraffin diagnosis. TAT and concordance were compared to glass diagnoses in the same period. RESULTS.­: For 748 intraoperative diagnoses by telemicroscopy, 694 had TATs with a mean of 18 minutes 56 seconds ± 8 minutes 45 seconds, which was slower than on glass (14 minutes 25 seconds ± 7 minutes 8 seconds, P < .001). Twenty-two (2.89% of available) were discordant, which was not significantly different from the on-glass rate (P = .44) or categorical distribution (P = .31). Two cases (0.27%) had technical failures. CONCLUSIONS.­: Although in-person diagnoses were statistically faster, the great majority of telemicroscopic diagnoses were returned in less than 20 minutes. This remained true through numerous pathologists, pathology assistants and/or technicians, different hospitals, and during a combined 6 years. The concentration of discordant diagnoses among relatively few pathologists suggests individual comfort with telepathology and/or frozen section diagnosis. In rare cases, technical issues prevented telemicroscopic diagnosis. Overall, this justifies continued use and expansion of telemicroscopic services in primary intraoperative diagnoses.

Tissue interaction is required for glenoid fossa development during temporomandibular joint formation.

The mammalian temporomandibular joint (TMJ) develops from two distinct mesenchymal condensations that grow toward each other and ossify through different mechanisms, with the glenoid fossa undergoing intramembranous ossification while the condyle being endochondral in origin. In this study, we used various genetically modified mouse models to investigate tissue interaction between the condyle and glenoid fossa during TMJ formation in mice. We report that either absence or dislocation of the condyle results in an arrested glenoid fossa development. In both cases, glenoid fossa development was initiated, but failed to sustain, and became regressed subsequently. However, condyle development appears to be independent upon the presence of the forming glenoid fossa. In addition, we show that substitution of condyle by Meckel's cartilage is able to sustain glenoid fossa development. These observations suggest that proper signals from the developing condyle or Meckel's cartilage are required to sustain the glenoid fossa development.

Successful integration of thyroid cytopathology and surgical pathology education in an E-module format.

Context: The shift to digital learning in medicine is well underway and in fact spurred by the COVID-19 pandemic. The didactic portion of our institution's cytotechnology (CT) education program is online and delivered to learners across the nation. With CT education elevating to the master's degree level, there is a need to expand cytologic correlation with surgical resection specimens. We also wanted to afford pathology residents the same. Methods: We developed an online cytologic-histologic correlation digital learning module (e-module) addressing thyroid fine needle aspirations (FNAs) and surgical thyroidectomy specimens which was administered as part of coursework in the CT education and pathology residency programs. The module was 35 min long and consisted of guided narration with both formative and summative interactive quizzes. After completion of the module, participants were invited to fill a brief survey comprised of multiple choice, Likert, and free response questions. This study was approved by the institutional review board. Results: The 29 respondents were comprised of 22 CT students and 7 residents. CT students had minimal experience thyroid pathology prior to the module; residents were mixed. Twenty-three (79.3%) ranked the highest tiers for learning cytopathology through this module, 24 (82.8%) for learning thyroid surgical pathology, and 25 (86.2%) for cytologic-histologic correlation. All respondents stated they would like similar activities in the future. Conclusions: Teaching cytology-histology correlation for thyroid in an electronic format was effective and well-received by participants. There is a demand for these activities among current learners, suggesting that expanding the available repertoire will be beneficial.

Pulmonary Hypertensive Changes Secondary to COVID-19 Pneumonia in a Chronically SARS-CoV-2-Infected Bilateral Lung Explant.

COVID-19, the syndrome caused by the novel coronavirus SARS-CoV-2, has spread throughout the world, causing the death of at least three million people. For the over 81 million who have recovered, however, the long-term effects are only beginning to manifest. We performed a bilateral lung transplant on a 31-year-old male patient for chronic hypoxic respiratory failure, severe pulmonary hypertension and radiographically identified pulmonary fibrosis five months after an acute COVID-19 infection. The explant demonstrated moderate pulmonary vascular remodeling with intimal thickening and medial hypertrophy throughout, consistent with pulmonary hypertension. The parenchyma demonstrated an organizing lung injury in the proliferative phase, with severe fibrosis, histiocytic proliferation, type II pneumocyte hyperplasia, and alveolar loss consistent with known COVID-19 pneumonia complications.This report highlights a novel histologic finding in severe, chronic COVID-19. Although the findings in acute COVID-19 pneumonia have been well-examined at autopsy, the chronic course of this complex disease is not yet understood. The case presented herein suggests that COVID-induced pulmonary hypertension may become more common as more patients survive severe SARS-CoV-2-related pneumonia. Pulmonologists and pulmonary pathologists should be aware of this possible association and look for the clinical, radiographic, and histologic criteria in the appropriate clinical setting.

p63 expression is associated with high histological grade, aberrant p53 expression and TP53 mutation in HER2-positive breast carcinoma.

AIM: p63, a member of the p53 family, is a myoepithelial cell marker usually expressed in metaplastic breast carcinoma and its expression suggests a myoepithelial phenotype. However, its expression and association with clinicopathological features of human epidermal growth factor receptor 2 (HER 2)-positive breast carcinoma is poorly investigated. MATERIALS AND METHODS: Sixty-seven patients with oestrogen receptor-negative and progesterone receptor-negative, HER2-positive breast carcinoma who received anti-HER2-based neoadjuvant±adjuvant therapy was retrospectively analysed. RESULTS: Twenty cases were p63-positive and 47 cases were p63-negative. The clinicopathological features and tumour responses after neoadjuvant therapy and outcomes were analysed. Among HER2-positive tumours, expression of p63 was significantly associated with younger age (42.5 vs 55.9; p=0.010). Expression of p63 was also significantly associated with histological grade 3 (11/20 (55%) vs 11/47 (23.4%); p=0.012) and negatively associated with grade 2 (9/20 (45%) vs 36/47 (76.6%); p=0.012). Intriguingly, p63-positive breast carcinomas showed significant aberrant p53 expression by immunohistochemistry (16/18 (88.9%) vs 29/47 (61.7%); p=0.03) and of TP53 mutation by Sanger sequencing (15/16 (93.8%) vs 12/22 (54.5%); p=0.009). No significant difference in tumour response after anti-HER2 neoadjuvant therapy nor in survival were found between p63-positive and p63-negative breast carcinomas. CONCLUSION: Expression of p63 in HER2-positive breast carcinoma is significantly associated with younger age, poor differentiation, high histological grade and aberrant expression of p53 and of TP53 mutation. HER2-positive breast carcinoma with a myoepithelial immunophenotype shows distinctive clinicopathological features representing a distinct subtype of HER2-positive breast carcinoma. Further, these findings suggest an interaction between p63 and mutant p53 in the tumorigenesis of HER2-positive breast carcinomas.

Poor histologic tumor response after adjuvant therapy in basal-like HER2-positive breast carcinoma.

AIMS: HER2-positive breast carcinomas are all treated with first-line anti-HER2 therapy. However, immunohistochemical and molecular profiling demonstrates significant heterogeneity among HER2-positive carcinomas. Basal-like HER2-positive breast carcinomas are poorly differentiated from pure HER2-positive breast carcinomas. MATERIALS AND METHODS: Seventy-five patients with HER2-positive, ER- and PR-negative breast carcinomas who received anti-HER2 based neoadjuvant therapy were retrospectively analyzed. Thirty-seven cases were classified as basal-like HER2-positive breast carcinoma with any positivity for CK5/6, and thirty-eight cases were classified as pure HER2-positive breast carcinoma with completely negativity for CK5/6. The clinicopathological features and tumor responses after neoadjuvant therapy and outcomes were analyzed. RESULTS: Compared to non-basal HER2-positive breast carcinoma, basal-like HER2-positive breast carcinoma showed distinctive histologic features including poor differentiation and syncytial tumor cells with pushing, invasive borders and a significantly higher proportion of apocrine metaplasia. They also demonstrated significantly higher histologic grade; 18/37 (48.6%) of basal-like carcinomas were grade 3, whereas only 5/38 (13.2%) of non-basal carcinomas were grade 3 (p = 0.001), Furthermore, basal-like HER2-positive breast carcinomas were more likely to be positive or completely negative for p53 (p = 0.009), and demonstrated a higher percentage of TP53 mutation (p = 0.17). These tumors were less responsive to anti-HER2 based neoadjuvant therapy, with Miller-Payne grades 1-3 higher than pure HER2-positive breast carcinoma (25/37 [67.6%] vs 16/38 [42.1%]), and the percentage of grade 4-5 was lower (12/37 [32.4%] vs 22/38 [57.9%]; p = 0.027). CONCLUSIONS: Basal-like HER2-positive breast carcinoma has distinctive clinicopathological features and less histologic tumor response after neoadjuvant therapy. There is urgent need to recognize basal-like HER2-positive breast carcinoma to be treated precisely.

Progress in triple negative breast carcinoma pathophysiology: Potential therapeutic targets.

Triple-negative breast carcinoma (TNBC) is a subtype of breast carcinoma defined by negativity for estrogen receptor (ER) or progesterone receptor (PR) by immunohistochemical analysis and negativity for human epidermal growth factor receptor (Her2) by immunohistochemistry or in situ hybridization. TNBC is clinically marked by its high aggressiveness, particularly poor outcomes including a low survival rate, and the lack of specific and effective treatments. Therefore, new potential targets for the treatment of TNBC must be identified. This review summarizes recent evidence supporting novel targets and possible therapeutic regimens in the treatment of TNBC.

Solid papillary carcinoma of the breast: A special entity needs to be distinguished from conventional invasive carcinoma avoiding over-treatment.

INTRODUCTION: Solid papillary carcinoma of the breast, a newly-defined entity, is poorly recognized, and its nature and management is still debated. MATERIAL AND METHODS: Eleven cases of pure solid papillary breast carcinoma in our archive and 253 cases reported in previous literature were retrospectively analyzed for their clinicopathological features and outcomes. RESULTS: The eleven cases occurred in elderly females. Grossly, all tumors were well-circumscribed and typically composed of solid papillary nodules. The tumor cells were bland-looking with low-grade atypia and mitoses < 5/10HPF. Immunophenotypically, all eleven cases showed positivity for ER and PR, negativity for CK5/6 and HER2, and a low proliferative index of Ki67. Five cases showed scattered positivity for myoepithelial marker p63, and four cases were positive for CK5/6 and CD10 around the nodules, whereas the other cases were completely negative for all myoepithelial markers. Five cases expressed the neuroendocrine marker synaptophysin, and six cases expressed chromogranin. In nine cases, mastectomy and axillary lymph nodes excision were performed, and only one showed micrometastasis in an axillary lymph node. There was no local recurrence or distant metastasis or breast carcinoma related-death during the follow-up periods of 50 months. Out of 253 solid papillary breast carcinomas reported in literature, the percentage of axillary lymph node metastasis was 4/136 (3%), with rare local recurrences and distant metastasis; only three patients died of breast carcinoma. CONCLUSION: Solid papillary carcinoma of the breast is a rare entity with distinctive clinicopathological features and excellent prognosis and should be distinguished from conventional breast carcinoma to avoid over-treatment.

EZH2 overexpression in different immunophenotypes of breast carcinoma and association with clinicopathologic features.

BACKGROUND: Enhancer of zest homolog 2 (EZH2), a histone 3 methyltransferase, is associated with aggressive behavior of many tumors and is a promising target of molecular therapy. METHODS: To better elucidate the relevance of EZH2 in breast cancer subtypes, we evaluated EZH2 expression in 226 invasive breast carcinomas with four distinct immunophenotypes and in association with clinicopathological features. RESULTS: Of these cases, 138 (61.1 %) were defined as EZH2-overexpressing with a multiplicative score > 3. EZH2 expression was inversely related to the status of ER and PR (Chi-square, p < 0.001), and it was significantly associated with HER2 positivity, high proliferative index, and high histologic grade (Chi-square, p < 0.05). ER-positive breast carcinoma with low proliferative index (Ki67 < 14 %) showed the lowest expression and triple-negative breast carcinoma showed the highest overexpression of EZH2, 18.5 % (10/54) versus 90.9 % (50/55) (Chi-square, p < 0.001). Intriguingly, 88 % (44/50) cases of grade 3 triple-negative breast carcinoma showed uniformly strong EZH2 expression with a multiplicative score of 9. The percentage of EZH2 overexpression in ER-positive breast carcinoma with a high proliferative index or HER2-positive cases were 61.2 and 74 %, respectively. Furthermore, EZH2 expression was significantly elevated in high-grade DCIS compared to benign lesions (90 % versus 0, p < 0.001). However, there is no association between EZH2 expression and the status of histone 3 lysine 27 trimethylation or other clinicopathologic features. CONCLUSION: In summary, triple-negative breast carcinoma showed the highest overexpression of EZH2. EZH2 overexpression is associated aggressive pathologic features including high nuclear grade, high proliferative index, and positivity of HER2 of breast carcinoma.

Teaching High School Students About Pathology: Development of a Secondary School-Focused Enrichment Course in Pathology and Physiology.

OBJECTIVES: Although pathology is a central discipline in medicine, many do not understand the role of pathologists and laboratory professionals. While there are efforts to educate the public, few focus on precollege students. METHODS: To define a curriculum exposing high school students to major concepts in health and disease, while introducing them to professions that employ this knowledge. A semester-long class was designed to meet for 2-hour sessions semiweekly. Each session included a lecture given by a pathologist followed by group activities including hands-on gross or virtual laboratory experiences and clinical simulations. Content included epidemiology, biostatistics, and the critical evaluation of health-related articles in the popular press. Students were evaluated by examination, group assignments, and a capstone research project presentation. RESULTS: Over 4 years (2011-2014), 114 of 122 students completed the course with a "B" or better. By course conclusion, students could articulate the link between tissue changes and clinical phenotypes. Surveys showed that 90% of students found the course appropriately challenging, 98% found the class appropriate for their learning style, and the teaching methods and course content received 99% approval. CONCLUSIONS: We present a pathology course geared toward high school students that taught the foundations of human disease that allowed students to fully understand and engage in the material. Students felt that the knowledge earned was valuable and helped them to understand human health as well as inform their future career choices. This course could serve as a model for public outreach programs and for secondary and postsecondary educators.

Genomic signatures in B-cell lymphoma: How can these improve precision in diagnosis and inform prognosis?

Current genomic technologies have immensely improved disease classification and prognostication of major subtypes of B-cell lymphomas. This novel genetic information has not only aided in diagnosis, but has also revealed a landscape of critical molecular events that determine the biological and clinical behavior of a lymphoma. In this review, we summarized the genetic characteristics of major subtypes of B-cell lymphomas, including diffuse large B cell lymphoma (DLBCL), follicular lymphoma (FL), Burkitt lymphoma (BL), and mantle cell lymphoma (MCL). We illustrated how genomic profiling had identified molecular subgroups in DLBCL with varied clinical outcomes, and how a subset of genes defined prognosis in MCL and aided in BL diagnoses. We also highlighted some Phase II/III clinical trials using new therapeutic agents to determine clinical efficacy in novel molecular subgroups with distinct gene expression patterns. We believe that refinement of genomic signatures will require more intensive efforts from the biomedical research community to improve targeted therapy designs and bring a substantial change in the treatment decisions. In the next era of genomic medicine, we anticipate that a clinically and biologically relevant molecular profile of each tumor will be obtained at diagnosis to guide therapy.

Genomic signatures in T-cell lymphoma: How can these improve precision in diagnosis and inform prognosis?

The novel genetic information gained from genome-wide high throughput techniques has greatly improved our understanding of peripheral T-cell lymphoma (PTCL). PTCL consists of numerous distinct entities and is currently diagnosed using a combination of clinical and morphologic features and immunophenotyping together with limited molecular assays leading to an often fragmented, complicated diagnostic system. The diagnosis of many cases is challenging even for expert hematopathologists and more than a third of the cases cannot be further classified and thus put into the PTCL-NOS category. Gene expression profiling (GEP) has significantly improved the molecular classification of PTCLs and identified robust molecular signatures for common nodal subtypes of PTCL including angioimmunoblastic T-cell lymphoma (AITL), anaplastic T-cell lymphoma (ALCL), adult T-cell leukemia/lymphoma (ATLL) and extra-nodal NK/T cell lymphoma (ENKTL). These studies also led to identification of novel molecular subtypes with distinct prognosis, that otherwise could not be identified by conventional methods. Integration of massive sequencing strategies and gene expression has characterized driver genetic alterations in common subtypes like AITL, ALCL, ENKTL and other PTCLs. These studies have identified oncogenic pathways and genes affected in specific disease subtypes that can be potentially targeted by specific therapies. Novel treatment options with FDA approved drugs directed towards mutant IDH2, the NF-κB, JAK/STAT, or mTOR pathways illustrate the usefulness of genome-wide techniques to identify targets for therapy. In this review, we highlight recent advances in the molecular diagnosis and prognosis of PTCL using these genome-wide techniques.