Congenital Myenteric Hypoganglionosis.

Congenital myenteric hypoganglionosis is a rare developmental disorder characterized clinically by severe and persistent neonatal intestinal pseudoobstruction. The diagnosis is established by the prevalence of small myenteric ganglia composed of closely spaced ganglion cells with sparse surrounding neuropil. In practice, the diagnosis entails familiarity with the normal appearance of myenteric ganglia in young infants and the ability to confidently recognize significant deviations in ganglion size and morphology.

Chromosomal microarray analysis of benign mesenchymal tumors with RB1 deletion.

Spindle cell lipomas/pleomorphic lipomas, mammary-type myofibroblastomas, and cellular angiofibromas are benign mesenchymal tumors that demonstrate histologically overlapping features but with varying anatomic locations and an uncertain etiologic relationship. These tumors have also been found to have an overlapping molecular profile with shared 13q14 deletions, which is the location of the tumor suppressor gene RB1 that encodes the retinoblastoma protein. Molecular studies thus far have largely focused on the RB1 locus, using primarily immunohistochemistry and fluorescence in situ hybridization to characterize RB1 status.

NF-κB upregulates glutamine-fructose-6-phosphate transaminase 2 to promote migration in non-small cell lung cancer.

Background: Epithelial-to-mesenchymal transition (EMT) results in changes that promote de-differentiation, migration, and invasion in non-small cell lung cancer (NSCLC). While it is recognized that EMT promotes altered energy utilization, identification of metabolic pathways that link EMT with cancer progression is needed. Work presented here indicates that mesenchymal NSCLC upregulates glutamine-fructose-6-phosphate transaminase 2 (GFPT2).

Cyclin D1 expression and polysomy in lymphocyte-predominant cells of nodular lymphocyte-predominant Hodgkin lymphoma.

Cyclin D1 protein expression in lymphocytes is classically associated with mantle cell lymphoma. Although increasingly recognized in other lymphoproliferative disorders, cyclin D1 expression and CCND1 gene abnormalities have not been well studied in nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL). Using a double stain for CD20/cyclin D1, we quantified cyclin D1 expression in 10 cases of NLPHL and correlated those findings with SOX11 expression, CCND1 gene abnormalities, and clinical data.

Comparison of Histological Characteristics of Acellular Dermal Matrix Capsules to Surrounding Breast Capsules in Acellular Dermal Matrix-Assisted Breast Reconstruction.

Introduction: Despite the widespread adaptation of acellular dermal matrix (ADM) to breast reconstruction, we are just now exploring how these materials integrate and perform in vivo. The goal of this study was to compare the histological characteristics between expander capsules to an area without the ADM.

Methods: Women undergoing implant-based breast reconstruction at the University of Virginia Health System using a decellularized regenerative dermal matrix were enrolled in this prospective, evaluator-blinded, institutional review board-approved study.

Relationships between preclinical course grades and standardized exam performance.

Success in residency matching is largely contingent upon standardized exam scores. Identifying predictors of standardized exam performance could promote primary intervention and lead to design insights for preclinical courses. We hypothesized that clinically relevant courses with an emphasis on higher-order cognitive understanding are most strongly associated with performance on United States Medical Licensing Examination Step exams and National Board of Medical Examiners clinical subject exams.

Epiphyseal presentation of non-Hodgkin's lymphoma of bone in two pediatric patients--one with primary lymphoma of bone.

We report two children with lymphoma of bone centered in the distal femoral epiphysis who presented with knee pain. Radiographs, magnetic resonance imaging (MRI) and computed tomography (CT) were performed on both patients prior to biopsy. Following biopsy, both patients had fluorodeoxyglucose ((18) F-FDG) positron emission tomography/CT (PET/CT) and whole-body technetium-99m (Tc-99m) scintigraphy performed for staging.

Morphology in conjunction with immunohistochemistry is sufficient for the diagnosis of mammary analogue secretory carcinoma.

The recently described mammary analogue secretory carcinoma (MASC) is a low-grade salivary gland malignancy that harbors the recurrent cytogenetic abnormality t(12;15) (p13;q25) ETV6-NTRK3. Confirmation of this is currently considered the gold standard for diagnosis. Some have postulated that morphology together with supporting immunohistochemistry is sufficient to diagnose MASC.

Lineage of origin in rhabdomyosarcoma informs pharmacological response.

Lineage or cell of origin of cancers is often unknown and thus is not a consideration in therapeutic approaches. Alveolar rhabdomyosarcoma (aRMS) is an aggressive childhood cancer for which the cell of origin remains debated. We used conditional genetic mouse models of aRMS to activate the pathognomonic Pax3:Foxo1 fusion oncogene and inactivate p53 in several stages of prenatal and postnatal muscle development.

DICER1 mutations in childhood cystic nephroma and its relationship to DICER1-renal sarcoma.

The pathogenesis of cystic nephroma of the kidney has interested pathologists for over 50 years. Emerging from its initial designation as a type of unilateral multilocular cyst, cystic nephroma has been considered as either a developmental abnormality or a neoplasm or both. Many have viewed cystic nephroma as the benign end of the pathologic spectrum with cystic partially differentiated nephroblastoma and Wilms tumor, whereas others have considered it a mixed epithelial and stromal tumor.

From slide sets to sound bites: teaching and learning pathology in the digital age.

Educational evolution is particularly important in pathology, particularly cytopathology, due to the vast amounts of independent learning required to master this field. In this study, learning challenges faced by pathology residents were addressed through a variety of educational modalities including 24 short (∼10 minute) online tutorials (dubbed "Sound Bites") covering selected topics in cytopathology as well as other areas of anatomic and clinical pathology. Additionally, residents were provided with an annotated glass slide set covering pediatric pathology with an associated multiple choice self-assessment as well as multiheaded microscope slide review sessions.

EWSR1 genetic rearrangements in salivary gland tumors: a specific and very common feature of hyalinizing clear cell carcinoma.

The Ewing sarcoma breakpoint region 1 (EWSR1) is translocated in many sarcomas. Recently, its rearrangement has been described in salivary gland hyalinizing clear cell carcinomas (HCCCs) and in a subset of soft tissue myoepitheliomas. This study examines the presence of the EWSR1 rearrangement in a variety of salivary gland lesions including classic myoepitheliomas and HCCCs.

Molecular Pathology of Sarcoma.

The rapid growth of tissue-based molecular pathology has changed the practice of the surgical pathologist signing out soft tissue tumors. This information is presented in a practical and succinct manner focusing on clinically validated findings that have diagnostic or therapeutic relevance. The approach is morphologically based and focuses on differential diagnoses and clinical scenarios.

Melanotic xp11.2 neoplasm of the ovary: report of a unique case.

We describe a primary ovarian neoplasm, occurring in a 15-year-old female patient, with morphologic, immunohistochemical, and molecular genetic features identical to those of the very rare tumors of the kidney previously described as "melanotic Xp11 translocation renal cancer." This represents, to the best of our knowledge, the first report of a melanotic Xp11 translocation-associated neoplasm arising outside of the kidney. We discuss the relationship of these rare tumors to neoplasms showing perivascular epithelioid cell differentiation, in particular those showing TFE3 rearrangements.

Evasion mechanisms to Igf1r inhibition in rhabdomyosarcoma.

Inhibition of the insulin-like growth factor 1 receptor (Igf1r) is an approach being taken in clinical trials to overcome the dismal outcome for metastatic alveolar rhabdomyosarcoma (ARMS), an aggressive muscle cancer of children and young adults. In our study, we address the potential mechanism(s) of Igf1r inhibitor resistance that might be anticipated for patients. Using a genetically engineered mouse model of ARMS, validated for active Igf1r signaling, we show that the prototypic Igf1r inhibitor NVP-AEW541 can inhibit cell growth and induce apoptosis in vitro in association with decreased Akt and Mapk phosphorylation.

Hepatocyte cytokeratin 7 expression in chronic allograft rejection.

We examined hepatocyte cytokeratin 7 (CK7) expression in chronic allograft rejection (CR), a ductopenic condition in which this has not been systematically evaluated, in 20 patients with the clinicopathologic diagnosis of CR and age-, sex-, and native-disease-matched control subjects. We also studied baseline biopsy specimens from both groups. Three pathologists independently reviewed H&E- and CK7-stained sections, counting interlobular bile ducts (BDs) and portal tracts (PTs), noting the morphologic pattern of injury and scoring hepatocyte CK7 expression (0, none; 1+, rare; 2+, multifocal, predominantly periportal; 3+, extension into the lobule; 4+, diffuse).

Imaging characteristics of angiomatoid fibrous histiocytoma of bone.

We present the first report of a patient with angiomatoid fibrous histiocytoma of bone in the radiology literature. This tumor initially eluded diagnosis due to its similarities with chronic hematoma and aneurysmal bone cyst. Only two cases of angiomatoid fibrous histiocytoma have been reported in the radiology literature and both of these lesions were in the soft tissues.

Death after endoscopic retrograde cholangiopancreatography: findings at autopsy.

More than half a million endoscopic retrograde cholangiopancreatography (ERCP) procedures are performed annually in the United States. The risk of severe complications after ERCP is less than 1%; however, autopsy pathologists see a select group of patients having fatality. Thirty-five autopsies were performed after ERCP over a 13-year period.

Credentialing a preclinical mouse model of alveolar rhabdomyosarcoma.

The highly aggressive muscle cancer alveolar rhabdomyosarcoma (ARMS) is one of the most common soft tissue sarcoma of childhood, yet the outcome for the unresectable and metastatic disease is dismal and unchanged for nearly three decades. To better understand the pathogenesis of this disease and to facilitate novel preclinical approaches, we previously developed a conditional mouse model of ARMS by faithfully recapitulating the genetic mutations observed in the human disease, i.e.

PAX immunoreactivity identifies alveolar rhabdomyosarcoma.

PAX5 is a member of the paired box transcription factors involved in development and its expression has been well characterized among hematopoietic malignancies of B-cell lineage. Its expression has also been reported in a subset of neuroendocrine carcinomas, urothelial tumors, Merkel cell carcinoma, glioblastoma, and neuroblastoma cell lines. As such, we sought to assess it as a diagnostic marker in the evaluation of pediatric small round blue cell tumors.

Diagnosis of hydatidiform moles using p57 immunohistochemistry and HER2 fluorescent in situ hybridization.

Fluorescent in situ hybridization (FISH) for HER2 performed on paraffin-embedded tissue samples and immunohistochemical analysis for p57 may be useful ancillary studies to aid in the diagnosis and classification of hydatidiform moles (HMs). HER2 FISH was validated against 24 paraffin-embedded sections of HMs and hydropic abortions and showed an 85% concordance rate. A morphologic assessment based on 44 cases showed 25% disagreement between original and consensus diagnosis based on H&E-stained slides, all of which involved the differential diagnosis of partial mole and hydropic abortion.