Cerebral metastases of malignant mesothelioma.

Malignant pleural mesothelioma represents a rare etiology of lung cancer metastasis to the brain. Neurologically symptomatic presentations are extremely rare as these metastatic lesions are detected in the late stages of the disease. Despite many highly heterogenous treatment techniques reported in the literature, overall survival is poor. A 72-year-old male with a history of mesothelioma presented with recurrent episodes of altered mental status, confusion and expressive aphasia. Imaging indicated a large hemorrhagic, enhancing lesion in the anterior left frontal lobe resulting in midline shift of 6 mm. He underwent a left frontal craniotomy for resection, after which he had complete resolution of symptoms. The resected mass was metastatic high-grade malignant mesothelioma. On a 1-month follow-up, new lesions in the bilateral frontal lobes were discovered, and despite undergoing adjuvant stereotactic radiosurgery, the right one grew significantly, causing notable mass effect. The patient successfully underwent a right craniotomy for resection.

Axillary lymphadenopathy in a liver transplant recipient: Initial manifestation of disseminated cryptococcosis.

Immunocompromised patients, especially organ transplant recipients, are at risk for opportunistic infections. Cryptococcus, a ubiquitous environmental fungus, can cause potentially fatal infection in such hosts. While it can involve any organ in the human body, respiratory and central nervous systems are commonly affected. We present a case of disseminated cryptococcal infection in a liver transplant recipient in whom the initial presentation was bilateral axillary lymphadenopathy, a relatively rare clinical manifestation. Rapid diagnosis and targeted antimicrobial therapy are paramount for favorable clinical outcomes, particularly in this patient population.

Symptomatic mature teratoma of the lumbar spine: A case report.

BACKGROUND: Teratomas are a unique family of tumors derived from two or more of the three embryonic layers: endoderm, mesoderm, and ectoderm. Mature teratomas are comprised the most well-differentiated tissue types and may contain skin, hair, teeth, smooth muscle, respiratory tissues, etc. Infrequently, mature teratomas may be found within the central nervous system and, in exceedingly rare cases, may be occur within the spinal cord itself (i.e., intramedullary/intradural). CASE DESCRIPTION: A 78-year-old female presented with a subacute progressive lower extremity paraparesis. The MR revealed a cystic 81 × 30 × 25 mm intradural/intramedullary spinal mass involving the distal conus with exophytic extension into the L1-L4 spinal canal. Following surgical intervention consisting of a L1-L4 laminectomy, the lesion was largely removed. Pathology of the mass confirmed a large mature teratoma containing a multilobulated cyst that intraoperatively compressed the conus and cauda equina. Immediately postoperatively, the patient significantly improved neurologically. However, on postoperative day 2, she acutely developed a change in mental status with the left gaze preference and hemiparesis. CT brain in the acute setting showed no evidence of causative pathology and subsequent MR brain was unremarkable. The patient's neurologic deficits progressively improved leading to eventual discharge. CONCLUSION: Intrathecal intramedullary/extramedullary mature teratomas of the conus that results in subacute cauda equina syndromes are rare. The differential diagnosis for such lesions exophytic to the conus must include mature teratomas which, though rare, may be readily resected resulting in generally favorable outcomes.

Eosinophilic globules in a classic ependymoma: evidence of a possible secretory role.

A number of neoplasms of the central nervous system can demonstrate diffuse eosinophilic globules, known to be secretory products of the corresponding cell type, but they have not been a salient feature in descriptions of classic ependymoma. Here, we present a case of a posterior fossa ependymoma demonstrating glassy PAS-positive, diastase-resistant, eosinophilic globules with light microscopic and ultrastructural features resembling Reissner fiber, the secretory product of the subcommissural organ. While there has been a single published description of an ependymoma with intra- and extracellular granulofibrillary material suggested to be evidence of secretory differentiation, ours is the first case to demonstrate diffuse eosinophilic globules in an ependymoma. The extent of globules allowed full study by electron microscopy to provide new insight into the secretory material and the surrounding structures. Our findings suggest that neoplastic ependymal cells can recapitulate the secretory capacity of the subcommissural organ.

Plasmablastic Lymphomas: Characterization of Tumor Microenvironment Using CD163 and PD-1 Immunohistochemistry.

This study aims to characterize the tumor microenvironment of plasmablastic lymphoma (PBL) in regard to the quantities of CD163(+) tumor associated macrophages (TAM) and PD1(+) tumor infiltrating lymphocytes (TIL). This article also reviews the existing knowledge of the role of PD-1/PD-L1 pathway in the tumor microenvironment of hematopoietic neoplasms, discusses potential mechanisms to explain our findings, and outlines areas for future studies. We performed CD163 and PD1 immunohistochemical studies in 11 cases classified as plasmablastic lymphoma, and recorded the percentages of positive TAMs and TILs. Based on previous studies, cut off values of ≥30% and >5% were used to classify the cases into high TAMs and TILs, respectively. We determined that the majority of cases (8 of 11, or 73%) had high percentage of TAMs, while only a minority had high percentage of TILs (3 of 11, or 27%). Our data shows a trend towards a negative correlation between TAMs and TILs (p=0.08), and a predominance of the pattern TAMhigh/TILlow (7 of 11, or 63%) compared to other patterns. The microenvironment of plasma-blastic lymphoma tends to show high percentage of TAMs (≥30%) combined with low percentage of TILs (≤5%). Additional studies are needed to determine the clinical significance of TILs and the influence of EBV and HIV infections on numbers of TILs in PBL. As high microenvironment TAMs have been associated with high microenvironment PD-L1 in other hematopoietic malignancies, our data supports the need for future studies on the expression of PD-L1 in PBL.

Single versus double-unit transfusion: Safety and efficacy for patients with hematologic malignancies.

OBJECTIVES: Although hemoglobin thresholds for red blood cell (RBC) transfusion have decreased, double-unit RBC transfusion practices persist. We studied the effects switching from predominantly double-unit to single-unit RBC transfusions had on utilization and clinical outcomes for malignant hematology patients. METHODS: Retrospective chart review compared malignant hematology patients before and after implementing single-unit RBC transfusion policy. Hemoglobin threshold was 8.0 g/dL for both groups. RBC utilization metrics included number of RBC units transfused, RBC units transfused per admission, and number of transfusion episodes. Clinical outcomes included length of stay, 30-day mortality, and outpatient RBC transfusion 30-days post-discharge. RESULTS: Baseline hemoglobin was similar in both groups. The single-unit group was transfused with fewer RBC units per admission (5.1 vs 4.5, P = 0.01) than the double-unit group, but had more transfusion episodes per admission (4.1 vs 2.7, P < 0.001). After implementing single-unit policy, a 29% reduction in RBC utilization was observed. Mean hemoglobin at discharge was lower in the single-unit group (8.9 vs 9.5 g/dL, P = 0.005). No significant differences in length of stay or 30-day mortality were observed. CONCLUSION: Transfusing malignant hematology patients with single RBC units is safe and efficacious. Electronic provider order systems facilitating RBC transfusion requests provide excellent adherence to transfusion policy.

Suture Embolism of the Left Superior Lobar Pulmonary Artery.

Endogenous pulmonary thromboemboli are a common cause of noncardiac sudden natural death. Embolism of exogenous material is a rare but potential finding in autopsies following surgeries, medical procedures, penetrating trauma, and nonparenteral drug abuse. This report describes the first case of a suture embolism of the left superior lobar pulmonary artery following complicated abdominal surgery.

Intraventricular Pilocytic Astrocytoma With KIAA1549/BRAF Fusion Arising in a 44-Year Old.

Rare pilocytic astrocytomas (PA) have been described to arise in the ventricles of children. They are even less common in this location for the adult population. We present the case of a 44-year old man presenting with vision and mental status changes. Brain imaging revealed an intraventricular mass within the right ventricular atrium, most consistent with a meningioma. Microscopic examination revealed a neoplasm composed of elongated to plump bipolar astrocytes arranged in a fascicular architecture, accompanied by foci containing numerous Rosenthal fibers. By immunohistochemistry, the tumor cells were positive for vimentin and glial fibrillary acid protein, whereas negative for epithelial membrane antigen. Isocitrate dehydrogenase 1 (R132H) was also negative. By fluorescence in situ hybridization, we detected a KIAA1549/BRAF fusion gene. These findings supported the diagnosis of intraventricular PA arising in an adult.

Eosinophilic Angiocentric Fibrosis: A Review and Update of Its Association With Immunoglobulin G4-Related Disease.

Eosinophilic angiocentric fibrosis is a rare indolent lesion of the head and neck region that has characteristic histologic findings of onionskin fibrosis and prominent eosinophils. Its pathogenesis has been poorly understood and has been most commonly attributed to hypersensitivity or previous trauma. Recently, the lesion has been included in the spectrum of immunoglobulin G4 (IgG4)-related disease. However, few of the existing cases of eosinophilic angiocentric fibrosis have been evaluated for IgG4+ and IgG+ plasma cells. Therefore, we provide an update on the clinical and histologic features of eosinophilic angiocentric fibrosis to increase awareness of the entity and encourage its further characterization as an IgG4-related disease.

Alveolar rhabdomyosarcoma in the cerebrospinal fluid.

Alveolar rhabdomyosarcoma (RMS) is an aggressive soft tissue mass demonstrating rapid growth, dissemination, and leptomeningeal spread. Primary diagnosis is usually established by core biopsy. In rare cases, cytopathologic evaluation is indicated to identify recurrent or metastatic disease. We present a case of a 24-year-old man with a previously diagnosed alveolar RMS of the foot who presented to our institution with back pain. A lumbar puncture was performed and the cerebrospinal fluid (CSF) showed atypical cells demonstrating nuclear enlargement, eccentricity, binucleation, and frequent karyorrhexis. Laminectomy and cytogenetic studies were subsequently performed, confirming metastatic disease. There are few published reports on the CSF appearance of RMS. However, because leptomeningeal involvement by RMS is primarily evaluated by lumbar puncture, awareness of the cytologic features is important for patient management.

Glioblastoma Survival Outcomes at a Tertiary Hospital in Appalachia: Factors Impacting the Survival of Patients Following Implementation of the Stupp Protocol.

BACKGROUND: Glioblastoma is a fatal brain cancer with low median and yearly survival rates. Standard of care for treating glioblastoma is gross total resection (GTR) coupled with the Stupp protocol, but various factors influence the interventions undertaken and survival achieved. As health disparities exist in rural areas, survival in these areas needs to be assessed to understand which factors detract from the successes of these standard medical interventions. METHODS: We retrospectively determined impact of age at diagnosis, number of lesions, the molecular marker O6-methylguanine methyltransferase (MGMT), extent of surgery, and completion of the Stupp protocol on survival in patients treated at West Virginia University Hospitals. We also compared our findings with a pre-Stupp protocol study done in West Virginia in 1996. RESULTS: Age <60 years at diagnosis, having the MGMT gene methylated, having a unifocal tumor, receiving GTR, adhering to the Stupp protocol, and undergoing a treatment course of GTR followed by the Stupp protocol significantly increased survival. Comparison with the 1996 study showed that although overall median survival has not increased, all interventions involving GTR have resulted in a significantly higher survival. CONCLUSIONS: We can serve our patient population by offering GTR to all adult patients with glioblastoma when no contraindications exist and ensuring that patients follow the Stupp protocol. After discharge, the Stupp protocol may not be followed or completed for a variety of reasons. In the future, we aim to assess these reasons and analyze other significant interventional and socioeconomic factors that influence survival.

Biallelic PMS2 Mutation and Heterozygous DICER1 Mutation Presenting as Constitutional Mismatch Repair Deficiency With Corpus Callosum Agenesis: Case Report and Review of Literature.

Constitutional mismatch repair deficiency syndrome is a cancer predisposition syndrome caused by autosomal recessive biallelic (homozygous) germline mutations in the mismatch repair genes (MLH1, MSH2, MSH6, and PMS2). The clinical spectrum includes neoplastic and non-neoplastic manifestations. We present the case of a 7-year-old boy who presented with T-lymphoblastic lymphoma and glioblastoma, together with non-neoplastic manifestations including corpus callosum agenesis, arachnoid cyst, developmental venous anomaly, and hydrocephalus. Gene mutation analysis revealed pathogenic biallelic mutations of PMS2 and heterozygous DICER1 variant predicted to be pathogenic. This report is the first to allude to a possible interaction of the mismatch repair system with DICER1 to cause corpus callosum agenesis.

Plasmablastic lymphoma versus plasmablastic myeloma: an ongoing diagnostic dilemma.

AIMS: To determine the utility of clinical, morphological and phenotypical features in the differential diagnosis of plasmablastic lymphoma and myeloma with plasmablastic features. METHODS: All plasmablastic neoplasms identified from a 15-year retrospective search were reviewed and classified into 'lymphoma', 'myeloma' or 'indeterminate'. The classification was then compared with the previously established clinical diagnosis. Lessons learned from this review were used to design a diagnostic algorithm for pathologists to use in the absence of known clinical history. RESULTS: The classification was possible in 10 of 11 cases, 8 lymphomas and 2 myelomas (n=2). No distinctive morphological or phenotypical features were identified. The most useful histopathological parameter was a positive Epstein-Barr virus in situ hybridisation. Presence of associated lymphadenopathy and/or oral mass in the absence of complete myeloma-defining signs was used to favour a diagnosis of lymphoma in 4 of 8 cases. CONCLUSIONS: The distinction between plasmablastic lymphoma from plasmablastic myeloma warrants detailed knowledge of clinical, radiological and laboratorial findings. New studies identifying distinctive phenotypical or genetic features are needed to improve the histopathological differentiation of plasmablastic neoplasms.

Lipomatous meningioma: Case report and review of the literature.

Lipomatous meningiomas are a very rare form of brain meningiomas consisting of fat accumulation within the tumor. Magnetic resonance imaging (MRI) or computerized tomographic (CT) imaging can be utilized to visualize the fat accumulations, but histopathologic staining is necessary in order to make a definitive diagnosis. The key histopathologic feature is the identification of adipocyte-like cells within the tumor, but other markers have also been identified. In this case report and review of the literature, we discuss how to recognize the symptoms associated with lipomatous meningiomas and the definitive treatment approach for these rare tumors.

Locus-specific targeting to the X chromosome revealed by the RNA interactome of CTCF.

CTCF is a master regulator that plays important roles in genome architecture and gene expression. How CTCF is recruited in a locus-specific manner is not fully understood. Evidence from epigenetic processes, such as X chromosome inactivation (XCI), indicates that CTCF associates functionally with RNA. Using genome-wide approaches to investigate the relationship between its RNA interactome and epigenomic landscape, here we report that CTCF binds thousands of transcripts in mouse embryonic stem cells, many in close proximity to CTCF's genomic binding sites. CTCF is a specific and high-affinity RNA-binding protein (Kd < 1 nM). During XCI, CTCF differentially binds the active and inactive X chromosomes and interacts directly with Tsix, Xite, and Xist RNAs. Tsix and Xite RNAs target CTCF to the X inactivation center, thereby inducing homologous X chromosome pairing. Our work elucidates one mechanism by which CTCF is recruited in a locus-specific manner and implicates CTCF-RNA interactions in long-range chromosomal interactions.

Retinoic acid accelerates downregulation of the Xist repressor, Oct4, and increases the likelihood of Xist activation when Tsix is deficient.

BACKGROUND: Imbalances in X-linked gene dosage between the sexes are resolved by transcriptionally silencing one of two X-chromosomes in female cells of the early mammalian embryo. X-inactivation is triggered by expression of the non-coding Xist gene. In turn, Xist is dually regulated by the antisense Tsix RNA and by the Oct4 pluripotency factor. Although there is general agreement that Tsix is an inhibitor of Xist, some laboratories have observed ectopic Xist induction in differentiating male ES cells when Tsix is mutated, whereas we have not observed significant changes in Xist. These observational differences have led to fundamentally diverse models of X-chromosome counting. Here, we investigate if different methods of cell differentiation and use of all -trans retinoic acid (RA) could be causative factors and how they might impact Xist expression. RESULTS: We compared suspension and cell-adhesion cultures in the presence or absence of RA and find that RA significantly impacts Xist expression in Tsix-mutant male cells. Whereas the standard embryoid body method infrequently leads to ectopic Xist expression, adding RA generates a significant number of Xist-positive male cells. However, while normal Xist clouds in wild-type female cells are robust and well-circumscribed, those found in the RA-treated mutant males are loosely dispersed. Furthermore, ectopic Xist expression does not generally lead to complete gene silencing. We attribute the effect of RA on Xist to RA's repressive influence on Oct4, a pluripotency factor recently shown to regulate Tsix and Xist. RA-treated ES cells exhibit accelerated decreases in Oct4 RNA levels and also display accelerated loss of binding to Xist intron 1. When Tsix is deficient, the faster kinetics of Oct4 loss tip the equilibrium towards Xist expression. However, the aberrant Xist clusters are unlikely to explain elevated cell death, as X-linked silencing does not necessarily correlate with the qualitatively aberrant Xist clusters. CONCLUSIONS: We conclude that RA treatment leads to premature downregulation of Oct4 and partial derepression of Xist irrespective of X-chromosome counting. RA-induced Xist clusters in male cells do not result in global or stable silencing, and excess cell death is not observed. These data and RA's known pleiotropic effects on ES transcription networks suggest that RA differentation bypasses normal X-inactivation controls and should be used judiciously. We propose that the likelihood of Xist expression is determined by a balance of multiple Xist activators and repressors, and that levels of Oct4 and Tsix are crucial toward achieving this balance.

Acute altitude-induced hypoxia suppresses plasma glucose and leptin in healthy humans.

To examine the effects of acute altitude-induced hypoxia on the hormonal and metabolic response to ingested glucose, 8 young, healthy subjects (5 men and 3 women; age, 26 +/- 2 years; body mass index, 23.1 +/- 1.0 kg/m(2)) performed 2 randomized trials in a hypobaric chamber where a 75-g glucose solution was ingested under simulated altitude (ALT, 4300 m) or ambient (AMB, 362 m) conditions. Plasma glucose, insulin, C-peptide, epinephrine, leptin, and lactate concentrations were measured at baseline and 30, 60, 90, and 120 minutes after glucose ingestion during both trials. Compared with AMB, the plasma glucose response to glucose ingestion was reduced during the ALT trial (P = .04). There were no differences in the insulin and C-peptide responses between trials or in insulin sensitivity based on the homeostasis model assessment of insulin resistance. Epinephrine and lactate were both elevated during the ALT trial (P < .05), whereas the plasma leptin response was reduced compared with AMB (P < .05). The data suggest that the plasma glucose response is suppressed at ALT, but this is not due to insulin per se because insulin and C-peptide levels were similar for both trials. Elevated plasma epinephrine and lactate during ALT are indicative of increased glycogenolysis, which may have masked the magnitude of the reduced glucose response. We conclude that, during acute altitude exposure, there is a rapid metabolic response that is accompanied by a shift in the hormonal milieu that appears to favor increased glucose utilization.

Telomeric RNAs mark sex chromosomes in stem cells.

Telomeric regions are known to be transcribed in several organisms. Although originally reported to be transcribed from all chromosomes with enrichment near the inactive X of female cells, we show that telomeric RNAs in fact are enriched on both sex chromosomes of the mouse in a developmentally specific manner. In female stem cells, both active Xs are marked by the RNAs. In male stem cells, both the X and the Y accumulate telomeric RNA. Distribution of telomeric RNAs changes during cell differentiation, after which they associate only with the heterochromatic sex chromosomes of each sex. FISH mapping suggests that accumulated telomeric RNAs localize at the distal telomeric end. Interestingly, telomeric expression changes in cancer and during cellular stress. Furthermore, RNA accumulation increases in Dicer-deficient stem cells, suggesting direct or indirect links to RNAi. We propose that telomeric RNAs are tied to cell differentiation and may be used to mark pluripotency and disease.

FoxH1 negatively modulates flk1 gene expression and vascular formation in zebrafish.

Flk1 is the major receptor for VEGF on endothelial cells. During embryogenesis, flk1 is required for both vasculogenesis and angiogenesis and abnormally elevated flk1 expression is often associated with pathological conditions in adults. While the biological function of flk1 has been studied extensively, very little is known about how the flk1 gene is regulated at the transcriptional level. Our transgenic study led to the identification of a flk1 endothelial enhancer positioned approximately 5 kb upstream of the flk1 translation initiation site. Binding sites for FoxH1, scl, ets and gata factors are found in the zebrafish flk1 endothelial enhancer, as well as in upstream sequences of mouse flk1 and human kdr genes, suggesting that the regulatory machinery for flk1/kdr is conserved from fish to mammals. The roles of scl, ets and gata factors in hemangioblasts have been well defined, but the significance of FoxH1 in vessel formation has not been explored previously. Here we show that FoxH1 binds to the flk1 endothelial enhancer in vitro and functions as a repressor for flk1 transcription in cultured cells. Consistent with these findings, the expression level of flk1 is elevated in embryos lacking both maternal and zygotic FoxH1. We further show that overexpression of FoxH1 has a negative effect on vascular formation that can be counteracted by the down-regulation of smad2 activity in zebrafish embryos. Taken together, our data provide the first evidence that flk1 is a direct target of FoxH1 and that FoxH1 is involved in vessel formation in zebrafish.