Collision tumors revealed by prospectively assessing subtype-defining molecular alterations in 904 individual prostate cancer foci.

BACKGROUNDProstate cancer is multifocal with distinct molecular subtypes. The utility of genomic subtyping has been challenged due to inter- and intrafocal heterogeneity. We sought to characterize the subtype-defining molecular alterations of primary prostate cancer across all tumor foci within radical prostatectomy (RP) specimens and determine the prevalence of collision tumors.METHODSFrom the Early Detection Research Network cohort, we identified 333 prospectively collected RPs from 2010 to 2014 and assessed ETS-related gene (ERG), serine peptidase inhibitor Kazal type 1 (SPINK1), phosphatase and tensin homolog (PTEN), and speckle type BTB/POZ protein (SPOP) molecular status. We utilized dual ERG/SPINK1 immunohistochemistry and fluorescence in situ hybridization to confirm ERG rearrangements and characterize PTEN deletion, as well as high-resolution melting curve analysis and Sanger sequencing to determine SPOP mutation status.RESULTSBased on index focus alone, ERG, SPINK1, PTEN, and SPOP alterations were identified in 47.5%, 10.8%, 14.3%, and 5.1% of RP specimens, respectively. In 233 multifocal RPs with ERG/SPINK1 status in all foci, 139 (59.7%) had discordant molecular alterations between foci. Collision tumors, as defined by discrepant ERG/SPINK1 status within a single focus, were identified in 29 (9.4%) RP specimens.CONCLUSIONInterfocal molecular heterogeneity was identified in about 60% of multifocal RP specimens, and collision tumors were present in about 10%. We present this phenomenon as a model for the intrafocal heterogeneity observed in previous studies and propose that future genomic studies screen for collision tumors to better characterize molecular heterogeneity.FUNDINGEarly Detection Research Network US National Cancer Institute (NCI) 5U01 CA111275-09, Center for Translational Pathology at Weill Cornell Medicine (WCM) Department of Pathology and Laboratory Medicine, US NCI (WCM SPORE in Prostate Cancer, P50CA211024-01), R37CA215040, Damon Runyon Cancer Research Foundation, US MetLife Foundation Family Clinical Investigator Award, Norwegian Cancer Society (grant 208197), and South-Eastern Norway Regional Health Authority (grant 2019016 and 2020063)

Prospective, multicentre study of screening, investigation and management of hyponatraemia after subarachnoid haemorrhage in the UK and Ireland

Background: Hyponatraemia often occurs after subarachnoid haemorrhage (SAH). However, its clinical significance and optimal management are uncertain. We audited the screening, investigation and management of hyponatraemia after SAH. Methods: We prospectively identified consecutive patients with spontaneous SAH admitted to neurosurgical units in the United Kingdom or Ireland. We reviewed medical records daily from admission to discharge, 21 days or death and extracted all measurements of serum sodium to identify hyponatraemia (<135 mmol/L). Main outcomes were death/dependency at discharge or 21 days and admission duration >10 days. Associations of hyponatraemia with outcome were assessed using logistic regression with adjustment for predictors of outcome after SAH and admission duration. We assessed hyponatraemia-free survival using multivariable Cox regression. Results: 175/407 (43%) patients admitted to 24 neurosurgical units developed hyponatraemia. 5976 serum sodium measurements were made. Serum osmolality, urine osmolality and urine sodium were measured in 30/166 (18%) hyponatraemic patients with complete data. The most frequently target daily fluid intake was >3 L and this did not differ during hyponatraemic or non-hyponatraemic episodes. 26% (n/N=42/164) patients with hyponatraemia received sodium supplementation. 133 (35%) patients were dead or dependent within the study period and 240 (68%) patients had hospital admission for over 10 days. In the multivariable analyses, hyponatraemia was associated with less dependency (adjusted OR (aOR)=0.35 (95% CI 0.17 to 0.69)) but longer admissions (aOR=3.2 (1.8 to 5.7)). World Federation of Neurosurgical Societies grade I–III, modified Fisher 2–4 and posterior circulation aneurysms were associated with greater hazards of hyponatraemia. Conclusions: In this comprehensive multicentre prospective-adjusted analysis of patients with SAH, hyponatraemia was investigated inconsistently and, for most patients, was not associated with changes in management or clinical outcome. This work establishes a basis for the development of evidence-based SAH-specific guidance for targeted screening, investigation and management of high-risk patients to minimise the impact of hyponatraemia on admission duration and to improve consistency of patient care

Characterization of CD34-deficient myofibroblastomas of the breast.

Mammary myofibroblastoma is a benign spindle cell tumor that can show variable morphologic patterns and lines of differentiation. Diffuse and strong immunohistochemical expression of CD34 is a characteristic of myofibroblastoma and greatly aids in confirming a diagnosis. Myofibroblastoma has been shown to belong to a family of CD34-positive tumors with similar morphology that show a deletion of 13q14, which includes RB1 and FOXO1A genes. The purpose of this study was to better understand a subset of myofibroblastomas that is characteristically CD34-deficient by immunohistochemistry. Six myofibroblastomas were studied by immunohistochemistry and fluorescence in situ hybridization (FISH) for RB1. Patients included five women and one man, aged 41-85 years (median, 52.5). Tumor size ranged from 0.4 to 1.5 cm (mean, 0.95). Tumors showed spindle cell morphology in five cases and epithelioid features in one case. Two tumors showed complete lack of CD34 staining. The remaining showed weak focal or weak patchy CD34 staining. Dichotomous staining was seen in one case with CD34-positive spindle cell areas and CD34-negative myxoid areas. All six tumors showed ER expression, five of six showed desmin expression, and four of six showed bcl-2 positivity. Two of six (33.3%) tumors showed deletion of RB1 by FISH, including one that showed loss of Rb immunohistochemical staining. Myofibroblastomas uncommonly show absent/focal expression of CD34, a potential diagnostic pitfall, particularly in small samples. Characteristic staining with other immunohistochemical markers is seen which can aid in confirming the diagnosis. These tumors may harbor deletion of RB1, similar to CD34-positive myofibroblastomas, and this deletion may not correlate with loss of Rb by immunohistochemistry

The burden of paediatric asthma in urban United States populations

Within the United States (US) paediatric population, asthma is the most common chronic disease. Its impact is most greatly appreciated with respect to quality of life. The importance of this condition has been recognised in the US with a significant national response; however, prevalence, morbidity, and mortality continue to rise. This review explores the extent of asthma in the US paediatric population, as well as strategies undertaken by US health services to address this childhood illness. In addition, this review assesses the efficacy of three evidence- and population-based asthma prevention strategies, namely immunotherapy, reduction of environmental triggers, and prevention of viral infections. </p

Fusions involving BCOR and CREBBP are rare events in infiltrating glioma.

BCOR has been recognized as a recurrently altered gene in a subset of pediatric tumors of the central nervous system (CNS). Here, we describe a novel BCOR-CREBBP fusion event in a case of pediatric infiltrating astrocytoma and further probe the frequency of related fusion events in CNS tumors. We analyzed biopsy samples taken from a 15-year-old male with an aggressive, unresectable and multifocal infiltrating astrocytoma. We performed RNA sequencing (RNA-seq) and targeted DNA sequencing. In the index case, the fused BCOR-CREBBP transcript comprises exons 1-4 of BCOR and exon 31 of CREBBP. The fused gene thus retains the Bcl6 interaction domain of BCOR while eliminating the domain that has been shown to interact with the polycomb group protein PCGF1. The fusion event was validated by FISH and reverse transcriptase PCR. An additional set of 177 pediatric and adult primary CNS tumors were assessed via FISH for BCOR break apart events, all of which were negative. An additional 509 adult lower grade infiltrating gliomas from the publicly available TCGA dataset were screened for BCOR or CREBBP fusions. In this set, one case was found to harbor a CREBBP-GOLGA6L2 fusion and one case a CREBBP-SRRM2 fusion. In a third patient, both BCOR-L3MBTL2 and EP300-BCOR fusions were seen. Of particular interest to this study, EP300 is a paralog of CREBBP and the breakpoint seen involves a similar region of the gene to that of the index case; however, the resultant transcript is predicted to be completely distinct. While this gene fusion may play an oncogenic role through the loss of tumor suppressor functions of BCOR and CREBBP, further screening over larger cohorts and functional validation is needed to determine the degree to which this or similar fusions are recurrent and to elucidate their oncogenic potential

Targeting the epichaperome as an effective precision medicine approach in a novel PML-SYK fusion acute myeloid leukemia.

The epichaperome is a new cancer target composed of hyperconnected networks of chaperome members that facilitate cell survival. Cancers with an altered chaperone configuration may be susceptible to epichaperome inhibitors. We developed a flow cytometry-based assay for evaluation and monitoring of epichaperome abundance at the single cell level, with the goal of prospectively identifying patients likely to respond to epichaperome inhibitors, to measure target engagement, and dependency during treatment. As proof of principle, we describe a patient with an unclassified myeloproliferative neoplasm harboring a novel PML-SYK fusion, who progressed to acute myeloid leukemia despite chemotherapy and allogeneic stem cell transplant. The leukemia was identified as having high epichaperome abundance. We obtained compassionate access to an investigational epichaperome inhibitor, PU-H71. After 16 doses, the patient achieved durable complete remission. These encouraging results suggest that further investigation of epichaperome inhibitors in patients with abundant baseline epichaperome levels is warranted