EGFR/CEP7 high polysomy is separate and distinct from EGFR amplification in glioblastoma as determined by fluorescence in situ hybridization

EGFR amplification in gliomas is commonly defined by an EGFR/CEP7 ratio of ≥2. In testing performed at a major reference laboratory, a small subset of patients had ≥5 copies of both EGFR and CEP7 yet were not amplified by the EGFR/CEP7 ratio and were designated high polysomy cases. To determine whether these tumors are more closely related to traditionally defined EGFR-amplified or nonamplified gliomas, a retrospective search identified 22 out of 1143 (1.9%) gliomas with an average of ≥5 copies/cell of EGFR and CEP7 with an EGFR/CEP7 ratio of <2 displaying high polysomy. Of these cases, 4 had insufficient clinicopathologic data to include in additional analysis, 15 were glioblastomas, 2 were IDH-mutant astrocytomas, and 1 was a high-grade glial neoplasm, NOS. Next-generation sequencing available on 3 cases demonstrated one with a TERT promoter mutation, TP53 mutations in all cases, and no EGFR mutations or amplifications, which most closely matched the nonamplified cases. The median overall survival times were 42.86, 66.07, and 41.14 weeks for amplified, highly polysomic, and nonamplified, respectively, and were not significantly different (p =  0.3410). High chromosome 7 polysomic gliomas are rare but our data suggest that they may be biologically similar to nonamplified gliomas.

Objective comparison of a sit to stand test to the walk test for the identification of unilateral lameness caused by cranial cruciate ligament disease in dogs

OBJECTIVE

The purpose of this study was to evaluate a sit to stand test with the walk test for the identification of unilateral cranial cruciate ligament rupture in dogs.

MATERIALS AND METHODS

Peak vertical force and vertical impulse were measured on a pressure-sensitive walkway, during a sit to stand test and walk test, and in 10 dogs with unilateral cranial cruciate ligament rupture and 18 non-lame dogs. Data collected were used to calculate symmetry indices (SI) of ipsilateral and contralateral hindlimbs (HL), diagonal limb pairs (DLP) and ipsilateral limb pairs (ILP).

RESULTS

The symmetry indices of peak vertical force of HL during the walk test and sit to stand test were 100% and 90% sensitive for discriminating lame and non-lame dogs respectively. The symmetry indices of vertical impulse of HLs during the walk test and sit to stand test were 100% and 50% sensitive for discriminating lame and non-lame dogs respectively. Analysis of ipsilateral and diagonal limb pairs did not improve the discrimination in either test. The time taken to collect data from the sit to stand test data was shorter than for the walk test.

CLINICAL SIGNIFICANCE

Whilst the sit to stand test required a shorter time for collection of data than the walk test, it did not accurately identify all dogs with lameness associated with CCLR, and thus has relatively limited clinical utility in its tested form.

Abstract 212: True2 duplex sequencing reveals a diverse landscape of unique somatic mutations beyond the surgical margins of high- and low-grade diffuse gliomas

Introduction: High- and low-grade diffuse gliomas commonly recur regardless of therapy. Here, we sought to detect and profile molecular evidence of disease in nearby brain tissue absent of tumor by standard-of-care clinical imaging.

Methods: Twenty-two patients presenting to the University of Utah with radiographic evidence of a new high- to low-grade intrinsic brain tumor were enrolled after providing written informed consent. Using intraoperative stereotactic guidance, tissue was acquired from bulky tumor (36 samples) and beyond the surgical margins in peritumoral edema (29 samples). All samples underwent somatic mutation discovery using a custom-designed 114 kb panel (115 genes) and True2 duplex sequencing. True2 is a duplex adapter-based technology developed and empirically validated to achieve &gt;95% sensitivity for an allele frequency ≥0.1% at a false positive rate of &lt;1 per 100 kb panel positions.

Results: Somatic mutations were detected in all samples regardless of radiographic location. The mean number of mutations was similar between bulky tumor and peritumoral edema (5.6±2.4 vs. 5.1±2.9 mutations/sample, respectively; P=0.48). Although the mean allele frequency of variants was higher in tumor compared to edema (16.0±21.2% vs. 11.2±17.4%, respectively; P=0.017), there was a strong overlap in the allele frequency ranges (tumor: 0.07% to 90.3% vs. edema: 0.10% to 75.6%). Notably, one-third of all the somatic mutations detected had an allele frequency &lt;0.5%. Common diagnostic mutations specific to each tumor type were present in both tumor and edema - TERT promoter mutations in glioblastoma and oligodendroglioma; IDH1/2 mutations in astrocytoma and oligodendroglioma. In edema, mutations associated with glioblastoma but unique to a single sample occurred in TP53, EGFR, PTEN, NF1, ATRX, SCN9A, and MTOR at an allele frequency ranging from 0.10% to 20.22%. The edema of astrocytomas similarly harbored unique mutations in TP53, PTEN, and NF1, but mutations in EGFR, ATRX, SCN9A, and MTOR were absent. In contrast to both glioblastoma and astrocytoma, oligodendrogliomas exhibited a diverse collection of unique CIC and PAFAH1B3 mutations in edema at an allele frequency between 0.13% and 3.63%.

Conclusions: The application of True2 technology to conduct a discovery search for very-low frequency somatic mutations found the molecular burden between tumor and adjacent edema to be remarkably similar. Our findings indicate an extensive tumor presence beyond the surgical margins in diffuse gliomas with unique and abundant somatic mutations that may form the foundation of recurrent lesions. Molecular analysis of adjacent tissue identified as radiographically unaffected by bulky tumor to better characterize the mutational landscape of migratory subclones may directly impact personalized medicine for high- and low-grade diffuse glioma patients.

Citation Format: Hunter Underhill, Michael Karsy, Christian Davidson, Sabine Hellwig, Samuel Stevenson, Sydney Vincenti, Charlie Dean, Brion Harrison, Eric Goold, Mary Bronner, Howard Colman, Randy Jensen. True2 duplex sequencing reveals a diverse landscape of unique somatic mutations beyond the surgical margins of high- and low-grade diffuse gliomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 212.

Infectious Pseudoaneurysm of the Internal Carotid Artery in a Child Secondary to Parapharyngeal Abscess

Infectious pseudoaneurysm is a rare condition characterized by arterial wall dilation, usually due to an adjacent infectious focus. We present an 8-year-old male with a 3-day history of progressive, severe headache 2 weeks after treatment for a parapharyngeal abscess. Computed tomography revealed a left internal carotid artery (ICA) pseudoaneurysm inferior to the skull base and a small parapharyngeal abscess inferior to the pseudoaneurysm. The patient was admitted for intravenous antibiotic treatment and underwent transfemoral endovascular coil occlusion of the cervical ICA pseudoaneurysm without complications. We discuss the presentation and management of rare vascular complications of parapharyngeal abscesses involving major arteries of the neck and the role of neurointerventional embolization in these cases.

Clinical utility of whole-genome DNA methylation profiling as a primary molecular diagnostic assay for central nervous system tumors-A prospective study and guidelines for clinical testing

Background

Central nervous system (CNS) cancer is the 10th leading cause of cancer-associated deaths for adults, but the leading cause in pediatric patients and young adults. The variety and complexity of histologic subtypes can lead to diagnostic errors. DNA methylation is an epigenetic modification that provides a tumor type-specific signature that can be used for diagnosis.

Methods

We performed a prospective study using DNA methylation analysis as a primary diagnostic method for 1921 brain tumors. All tumors received a pathology diagnosis and profiling by whole genome DNA methylation, followed by next-generation DNA and RNA sequencing. Results were stratified by concordance between DNA methylation and histopathology, establishing diagnostic utility.

Results

Of the 1602 cases with a World Health Organization histologic diagnosis, DNA methylation identified a diagnostic mismatch in 225 cases (14%), 78 cases (5%) did not classify with any class, and in an additional 110 (7%) cases DNA methylation confirmed the diagnosis and provided prognostic information. Of 319 cases carrying 195 different descriptive histologic diagnoses, DNA methylation provided a definitive diagnosis in 273 (86%) cases, separated them into 55 methylation classes, and changed the grading in 58 (18%) cases.

Conclusions

DNA methylation analysis is a robust method to diagnose primary CNS tumors, improving diagnostic accuracy, decreasing diagnostic errors and inconclusive diagnoses, and providing prognostic subclassification. This study provides a framework for inclusion of DNA methylation profiling as a primary molecular diagnostic test into professional guidelines for CNS tumors. The benefits include increased diagnostic accuracy, improved patient management, and refinements in clinical trial design.

Microbiome and Neurotrauma: Emerging Innovations

The gut-brain axis plays an important role in bidirectional communication that exists and can be altered by injury. Neurotrauma provides acute alteration in the GI tract and alters autonomic function. In this focused review, we highlight what is known about GI disruption following neurotrauma. We then delve into how this affects recovery. Areas of innovation and emerging pre-clinical results are addressed. Finally, we address the link between neurotrauma induced GI dysfunction and progression to neurodegenerative disease states.

662 ENHANCING CARE BY IMPROVING DISCHARGE SUMMARIES

Introduction

Within the Geriatric Medicine department at the Lister Hospital, Stevenage, the timeliness and quality of discharge summaries had become a source of complaints. Both primary care practitioners and families reported documentation was inadequate or incorrect. This project aimed to improve the quality of these discharge summaries in accordance with standards generated from previous audit data. Through improving communication it was clear that patient care could be enhanced.

Methods

Each month 15 discharge summaries were selected at random for review. Alongside patient notes these summaries were appraised in regards to standard discharge summary requirements: timeliness of delivery; adequate description of admission; and documentation of the follow up plan. They were also appraised on documentation of specific requirements for older aged adults including cognitive status, mobility status, discharge destination, need for home help, Rockwood Frailty score and resuscitation and escalation plans. Interventions including informal communication with junior doctors, circulation of a ‘Top Tips’ sheet, generation of an information poster and dissemination of information at local teaching sessions, took place, and were assessed, over regular PDSA cycles.

Results

showed a clear, sustained improvement in the quality of the discharge summaries. At the end of data collection, 100% of discharge summaries contained an adequate description of admission and an appropriate follow up plan. There was also significant improvement in documentation of specific requirements. Where documentation was initially very limited, following interventions, most discharge summaries contained details pertaining to discharge destination, need for home support, mobility status and resuscitation and escalation plans.

Conclusion

The relatively simple interventions have been found to have a sustained improvement in the quality of discharge summaries from the Geriatric Medicine Department at Lister Hospital, Stevenage. Whilst more work needs to be done it is hoped that this will already have enhanced patient care.

Perioperative Outcomes After Tracheostomy Placement Among Complex Pediatric Patients

OBJECTIVES/HYPOTHESIS

To compare perioperative outcomes after pediatric tracheostomy placement based on patient complexity.

STUDY DESIGN

Retrospective case series.

METHODS

All patients that underwent tracheostomy placement at a tertiary children's hospital between 2015 and 2019 were followed. Children with a history of major cardiac surgery, sepsis, or total parental nutrition (TPN) were grouped as complex. Admission length, tracheostomy-related complications, in-hospital mortality, and 30-day readmissions were recorded among complex and non-complex patients.

RESULTS

A total of 238 children were included. Mean age at tracheostomy was 39.9 months (SD: 61.3), 51% were male and 51% were complex. Complex patients were younger at admission (29.9 vs. 46.8 months, P = .03), more likely to have respiratory failure (81% vs. 53%, P < .001) and more often required mechanical ventilation at discharge (86% vs. 67%, P < .001). An additional 33 days after placement was required for complex children (95% CI: 14-51, P = .001) and this group had more deaths (8% vs. 1%, P = .02); however, both groups had similar complication and readmission rates (P > .05). Total charges were higher among complex patients ($700,267 vs. $338,937, P < .001). Parametric survival analysis identified mechanical ventilation and patient complexity interacting to predict post-tracheostomy admission length.

CONCLUSIONS

Hospital discharge after pediatric tracheostomy was associated with patient complexity and further influenced by mechanical ventilation. Recognition that cardiac surgery, sepsis, or TPN can predict poorer perioperative outcomes can provide quality improvement strategies for these vulnerable children.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E2469-E2474, 2021.

A comparative analysis of kratom exposure cases in Thailand and the United States from 2010-2017

Background: Interest in the Southeast Asian natural remedy kratom has increased in Western countries recently, along with increasing concern over its potential toxic effects.Objective: To describe and compare demographics, common co-exposure substances, clinical effects, treatments, and medical outcomes of kratom "abuse" exposures in the United States (US) and Thailand.Methods: This is a retrospective analysis of kratom "abuse" exposures, defined as use when attempting to gain a psychotropic effect, reported to the National Poison Data System (NPDS) in the US and the Ramathibodi Poison Center (RPC) in Thailand from 2010 to 2017. Multivariate analysis identified risk factors for severe medical outcomes, defined as both ICU admissions and death.Results: Nine-hundred-twenty-eight cases were included (760 from NPDS and 168 from RPC). A greater proportion of cases involved co-exposures in Thailand (64.8% versus 37.4%; odds ratio [OR] = 3.10, 95% confidence interval [CI] = 2.15-4.47, p < .01). Both countries had a similar prevalence of opioid and benzodiazepine co-ingestions, but the US had more co-ingestions with other sedatives (4.6% versus 0%, OR = 0, 95% CI = 0-0.47, p < .01). Common clinical effects included tachycardia (30.4%), agitation/irritability (26.2%), and drowsiness/lethargy (21.1%). Six deaths occurred, including one single-substance exposure in the US, three multiple-substance exposures in the US, and two multiple-substance exposures in Thailand. Severe medical outcomes were reported more frequently in the US (OR = 18.82, 95% CI = 5.85-60.56, p < .01).Conclusions: Despite lower frequencies of co-ingestants overall, US kratom abuse exposures yielded greater clinical severity. This disparity may be attributable to differences in the products labeled "kratom," greater sedative co-exposures in the US, and/or differences in population genetics or use patterns.

Challenges of targeting BRAF V600E mutations in adult primary brain tumor patients: a report of two cases

Aim: Therapeutic targeting of BRAF alterations in primary brain tumor patients has demonstrated clinical activity in case reports and early trials; however, there is limited high-level evidence of the efficacy. Patients & results: Targeting BRAF V600E mutations with concurrent dabrafenib and trametinib in anaplastic pleomorphic xanthoastrocytoma resulted in a transient radiographic and clinical response and no therapeutic benefit in a patient with an epithelioid glioblastoma. Conclusion:BRAF/MEK inhibition did not produce a durable treatment effect in glioblastoma or pleomorphic xanthoastrocytoma with BRAF V600E alterations. Heterogenicity of related cases in the literature makes an evaluation of efficacy BRAF targeting therapies in gliomas difficult and requires additional investigation.

COMP-10. THE MUTATIONAL PROFILE OF GLIOBLASTOMA-DERIVED CELL-FREE DNA IN PLASMA REPRESENTS A DISTINCT SUBSET OF THE SOMATIC MUTATIONS PRESENT IN GLIOBLASTOMA SOLID TUMOR DNA

Glioblastoma’s mutational landscape varies widely in the same tumor. Using conventional criteria to identify mutations from a focal tissue specimen (e.g., variant allele frequency > 5%) undersamples glioblastoma’s broad clonal diversity, which may limit detection of glioblastoma-derived circulating cell-free DNA in plasma (i.e., circulating tumor DNA; ctDNA). Here, we sought to enhance somatic variant identification in solid tumor DNA to improve detection and characterize glioblastoma-derived ctDNA. Tumor DNA and plasma cell-free DNA (collected < 24 hours prior to the surgical procedure) were isolated from eight glioblastoma patients. DNA was capture-enriched using a custom-designed, glioblastoma-targeted, next-generation sequencing panel (124 genes, 118 kb) followed by paired-end sequencing. Samples were prepared in duplicate with molecular barcodes to enable detection of very-low frequency variants. Somatic mutations in tumor DNA were identified using variable allele frequency thresholds and were considered positive in ctDNA if present in both duplicate samples. Using a lower allele frequency threshold to identify mutations in tumor DNA significantly increased detection of ctDNA (F(1.04,7.29)=14.81, P=0.006). At a solid tumor allele frequency threshold of ≥ 5%, only a single patient (12.5%) had tumor mutations detected in ctDNA. However, at a threshold ≥ 1%, all patients (100%) had at least one tumor mutation detected in ctDNA. Moreover, at a threshold ≥ 0.5%, 7 out of 8 patients (87.5%) had > 12 tumor mutations present in ctDNA. The increased detection of ctDNA enabled the subsequent discovery that somatic mutations in APC, KIT, MSH6, and NF1 were more likely to be present in ctDNA compared to somatic mutations in ATRX, LZTR1, SLC26A3, and TERT which were absent in ctDNA (χ 2=8.0, P=0.005). Thus, stronger sampling of glioblastoma’s genetic heterogeneity in tumor DNA improves detection of ctDNA allowing comparisons between mutational profiles that may lead to the identification of similarities and differences with key biologic and/or clinical implications.

Two well-differentiated pancreatic neuroendocrine tumor mouse models

Multiple endocrine neoplasia type 1 (MEN1) is a genetic syndrome in which patients develop neuroendocrine tumors (NETs), including pancreatic neuroendocrine tumors (PanNETs). The prolonged latency of tumor development in MEN1 patients suggests a likelihood that other mutations cooperate with Men1 to induce PanNETs. We propose that Pten loss combined with Men1 loss accelerates tumorigenesis. To test this, we developed two genetically engineered mouse models (GEMMs)-MPR (Men1^flox/flox Pten^flox/flox RIP-Cre) and MPM (Men1^flox/flox Pten^flox/flox MIP-Cre) using the Cre-LoxP system with insulin-specific biallelic inactivation of Men1 and Pten. Cre in the MPR mouse model was driven by the transgenic rat insulin 2 promoter while in the MPM mouse model was driven by the knock-in mouse insulin 1 promoter. Both mouse models developed well-differentiated (WD) G1/G2 PanNETs at a much shorter latency than Men1 or Pten single deletion alone and exhibited histopathology of human MEN1-like tumor. The MPR model, additionally, developed pituitary neuroendocrine tumors (PitNETs) in the same mouse at a much shorter latency than Men1 or Pten single deletion alone as well. Our data also demonstrate that Pten plays a role in NE tumorigenesis in pancreas and pituitary. Treatment with the mTOR inhibitor rapamycin delayed the growth of PanNETs in both MPR and MPM mice, as well as the growth of PitNETs, resulting in prolonged survival in MPR mice. Our MPR and MPM mouse models are the first to underscore the cooperative roles of Men1 and Pten in cancer, particularly neuroendocrine cancer. The early onset of WD PanNETs mimicking the human counterpart in MPR and MPM mice at 7 weeks provides an effective platform for evaluating therapeutic opportunities for NETs through targeting the MENIN-mediated and PI3K/AKT/mTOR signaling pathways.

A Standardized Approach to Cesarean Surgical Technique and Its Effect on Operative Time and Surgical Morbidity

OBJECTIVE

To evaluate the impact of a standardized surgical technique for primary cesarean deliveries (CDs) on operative time and surgical morbidity.

MATERIALS AND METHODS

Two-year retrospective chart review of primary CD performed around the implementation of a standardized CD surgical technique. The primary outcome was total operative time (TOT). Secondary outcomes included incision-to-delivery time (ITDT), surgical site infection, blood loss, and maternal and fetal injuries.

RESULTS

When comparing pre- versus postimplementation surgical times, there was no significant difference in TOT (76.5 vs. 75.9 minutes, respectively; p = 0.42) or ITDT (9.8 vs. 8.8 minutes, respectively; p = 0.06) when the entire cohort was analyzed. Subgroup analysis of CD performed early versus late in an academic year among the pre- and postimplementation groups showed no significant difference in TOT (79.3 early vs. 73.8 minutes late; p = 0.10) or ITDT (10.8 early vs. 8.8 minutes late; p = 0.06) within the preimplementation group. In the postimplementation group, however, there was significant decrease in TOT (80.5 early vs. 71.3 minutes late; p = 0.02) and ITDT (10.6 early vs. 6.8 minutes late; p < 0.01). Secondary outcomes were similar for both groups.

CONCLUSION

A standardized surgical technique combined with surgical experience can decrease TOT and ITDT in primary CD without increasing maternal morbidity.

Two-stage surgical treatment for a giant sellar psammomatoid juvenile ossifying fibroma: case report

Psammomatoid juvenile ossifying fibroma (PJOF) is an uncommon, benign fibro-osseous tumor. It is a purely surgical disease, and a review of the literature revealed that adjuvant therapies, including chemotherapy and radiation, play a limited role. The authors report the case of a 16-year-old male refugee who presented with a giant sinonasal PJOF with parasellar invasion, after having been unable to undergo earlier surgical treatment. The delay in presentation resulted in a large lesion with bilateral optic nerve compression, blindness, and frontal lobe compression. The patient was surgically treated with a two-stage combined cranial and endoscopic endonasal surgical approach. The delay in treatment and significant neurological compromise, which necessitated a two-stage approach, are unique from previously reported cases of PJOF.

Proteinase-activated receptor-2 blockade inhibits changes seen in a chronic murine asthma model

BACKGROUND

Proteinase-Activated Receptor-2 (PAR₂ ) is a G protein-coupled receptor activated by serine proteinases. We have shown that PAR₂ activation in the airways is involved in the development of allergic inflammation and airway hyperresponsiveness (AHR) in acute murine models. We hypothesized that functional inhibition of PAR₂ prevents allergic inflammation, AHR and airway remodeling in chronic allergic airway inflammation models.

MATERIAL AND METHODS

We developed and used a 12 week model of cockroach extract (CE)-mediated AHR, airway inflammation and remodeling in BALB/c mice.

RESULTS

Mice sensitized and challenged with CE for 12 weeks exhibit AHR, increased numbers of eosinophils in bronchoalveolar lavage (BAL) and increased collagen content in the lung tissue compared to saline controls. Administration of an anti-PAR₂ antibody, SAM-11, after the initial development of airway inflammation significantly inhibited all these parameters.

CONCLUSIONS

Our data demonstrate that PAR₂ signaling plays a key role in CE-induced AHR and airway inflammation/remodeling in long term models of allergic airway inflammation. Targeting PAR₂ activation may be a successful therapeutic strategy for allergic asthma.

Abstract 1538: A mouse model that mimics human MEN1 tumor is effective in preclinical neuroendocrine tumor therapeutics

Conditional knockout of Men1 in β cells leads to development of pituitary adenomas and pancreatic neuroendocrine tumors (PanNETs) by the age of eight to twelve months. This suggests that other events, like loss of additional mutations, may be required for development of tumors in the absence of MEN1. Since it was reported that mutations in genes of PI3K/mTOR pathway are found in human neuroendocrine tumors, we hypothesized that double deletion of PTEN and MEN1 may accelerate neuroendocrine tumorigenesis. Mice with double deletion of PTEN and MEN1 in β cells were produced by crosses among mice with Cre gene under the control of Rat Insulin promoter (Rip-Cre), floxed allele Men1 (Men1fl/fl), and Pten (Ptenfl/fl). Then mice with the genotype of Men1fl/fl Ptenfl/fl Rip-Cre were monitored for development of tumors. Consistent with our hypothesis, mice with conditional deletion of PTEN and MEN1 leads to fully developed PanNETs and pituitary adenomas by three to four months old, much earlier than that with Men1 deletion alone. These tumors resemble human MEN1 tumors at a histological and molecular level. Activation of phospho-AKT was observed in these tumors and Rapamycin treatments lead to delayed PanNETs and pituitary adenomas for at least two months. This mouse model (Men1fl/fl Ptenfl/fl Rip-Cre) directly supports that PI3K/mTOR pathway plays a critical role in neuroendocrine tumorigenesis, and also provides a platform to study new therapeutic opportunities for PanNETs and neuroendocrine tumors of the pituitary through the targeting of PI3K/mTOR pathway and MEN1 pathway. This model represents an important tool for studying the biology and preclinical therapeutics of human neuroendocrine tumors.

Citation Format: Chung Wong, Richard Clausen, Laura Tang, Christian Davidson, Evan Vosburgh, Arnold Levine, Eugenia Xu. A mouse model that mimics human MEN1 tumor is effective in preclinical neuroendocrine tumor therapeutics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1538. doi:10.1158/1538-7445.AM2017-1538

Population-based study demonstrating an increase in colorectal cancer in young patients

BACKGROUND

New Zealand has among the highest rates of colorectal cancer in the world and is an unscreened population. The aim of this study was to determine the trends in incidence and tumour location in the New Zealand population before the introduction of national colorectal cancer screening.

METHODS

Data were obtained from the national cancer registry and linked to population data from 1995 to 2012. Incidence rates for colorectal cancer by sex, age (less than 50 years, 50-79 years, 80 years or more) and location (proximal colon, distal colon and rectum) were assessed by linear regression.

RESULTS

Among patients aged under 50 years, the incidence of distal colonic cancer in men increased by 14 per cent per decade (incidence rate ratio (IRR 1·14), 95 per cent c.i. 1·00 to 1·30; P = 0·042); the incidence of rectal cancer in men increased by 18 per cent (IRR 1·18, 1·06 to 1·32; P = 0·002) and that in women by 13 per cent (IRR 1·13, 1·02 to 1·26; P = 0·023). In those aged 50-79 years, there was a reduction in incidence per decade of proximal, distal and rectal cancers in both sexes. In the group aged 80 years and over, proximal cancer incidence per decade increased by 19 per cent in women (IRR 1·19, 1·13 to 1·26; P < 0·001) and by 25 per cent in men (IRR 1·25, 1·18 to 1·32; P < 0·001); among women, the incidence of distal colonic cancer decreased by 8 per cent (IRR 0·92, 0·86 to 0·98); P = 0·012), as did that of rectal cancer (IRR 0·92, 0·86 to 0·97; P = 0·005).

CONCLUSION

The increasing incidence of rectal cancer among younger patients needs to be considered when implementing screening strategies.

The Role of MRgLITT in Overcoming the Challenges in Managing Infield Recurrence After Radiation for Brain Metastasis

Radiation necrosis and tumor recurrence are common sequelae after radiation therapy for brain metastasis. The differentiation of radiation necrosis and recurrent brain metastases continues to remain a difficult task despite a number of diagnostic methods. Techniques including magnetic resonance imaging, diffusion-weighted imaging, nuclear studies, and the gold standard of biopsy have all been studied for their effectiveness in accurately diagnosing the postradiation condition. Various specific treatment options of the distinct pathologies are available with the general theory that recurrences require more immediate treatment whereas radiation necrosis can be observed until symptomatic before intervention. This further emphasizes the necessity to accurately diagnose the condition to start appropriate and effective treatment. Despite both pathologies being pathophysiologically distinct, controversies exist as to whether there should be a distinction made at all or if the two can be perceived as a single condition if treatment and presentation are similar enough. Furthermore, a single treatment option such as magnetic resonance–guided, laser-induced thermal therapy (MRgLITT) can be used, potentially eliminating the need to differentiate the 2 entities because it successfully treats both conditions while being minimally invasive.

Functional inhibition of PAR2 alleviates allergen-induced airway hyperresponsiveness and inflammation

BACKGROUND

Proteinase-activated receptor 2 (PAR2 ) is a G protein-coupled receptor activated by trypsin-like serine proteinases. PAR2 activation has been associated with inflammation including allergic airway inflammation. We have also shown that PAR2 activation in the airways leads to allergic sensitization. The exact contribution of PAR2 in the development of eosinophilic inflammation and airway hyperresponsiveness (AHR) in sensitized individuals is not clear.

OBJECTIVE

To investigate whether functional inhibition of PAR2 during allergen challenge of allergic mice would inhibit allergen-induced AHR and inflammation in mouse models of asthma.

METHODS

Mice were sensitized and challenged with ovalbumin (OVA) or cockroach extract (CE). To investigate the role of PAR2 in the development of AHR and airway inflammation, we administered blocking anti-PAR2 antibodies, or a cell permeable peptide inhibitor of PAR2 signalling, pepducin, i.n. before allergen challenges and then assessed AHR and airway inflammation.

RESULTS

Administration of anti-PAR2 antibodies significantly inhibited OVA- and CE-induced AHR and airway inflammation. In particular, two anti-PAR2 antibodies, the monoclonal SAM-11 and polyclonal B5, inhibited AHR, airway eosinophilia, the increase of cytokines in the lung tissue and antigen-specific T cell proliferation, but had no effect on antigen-specific IgG and IgE levels. Pepducin was also effective in inhibiting AHR and airway inflammation in an OVA model of allergic airway inflammation.

CONCLUSIONS AND CLINICAL RELEVANCE

Functional blockade of PAR2 in the airways during allergen challenge improves allergen-induced AHR and inflammation in mice. Therefore, topical PAR2 blockade in the airways, through anti-PAR2 antibodies or molecules that interrupt PAR2 signalling, has the potential to be used as a therapeutic option in allergic asthma.

Developing Treatments for Stimulant Abuse: A Brief Overview

The abuse of stimulants such as cocaine, amphetamine, and methamphetamine is a huge problem in many parts of the world. Abuse of these drugs does not ruin just the user's life, but also adversely affects those around them. Despite many years of research, there are no approved medications for stimulant dependence, and treatment is focused on psychotherapy and abstinence. Over the last 10 to 20 years, there have been some major changes in approach to medication development for stimulant dependence. These include assessing ligands for non-dopaminergic sites, atypical dopamine transporter ligands, blocking long-term potentiation and / or memory reconsolidation, vaccines against the stimulant, and molecular approaches including pharmacogenomics and gene silencing. Also included in this overview are non-drug treatments such as deep brain stimulation and psychosurgery. This overview highlights recent preclinical and clinical studies of treatment development for stimulant dependence.

A feasibility study of behavioural activation for depressive symptoms in adults with intellectual disabilities

BACKGROUND

Important work has been carried out adapting cognitive behavioural therapy for people with intellectual disabilities. However, there is a lack of alternative psychological therapies available for people with intellectual disabilities and emotional difficulties. Behavioural activation for depression is less reliant on verbal communication and focuses on increasing purposeful activity and reducing avoidance.

METHOD

This feasibility study involved the development and piloting of an adapted manual of behavioural activation for people with intellectual disabilities. The intervention consisted of 10-12 sessions and a key adaptation was that the therapist worked with the clients alongside a significant other in their life, either a paid carer or family member. Baseline, post-intervention (3 months after entering the study) and 6-month quantitative follow-up data were obtained. Primary outcome data were gathered, concerning depressive symptoms, participants' levels of activity and general well-being.

RESULTS

Twenty-three adults with intellectual disabilities with symptoms of depression were recruited from specialist health services. In terms of acceptability, the behavioural activation intervention was well received and only two individuals dropped out, with a further two lost to follow-up. The main measures of depression appeared to be sensitive to change. Pre- to post-intervention data showed a significant reduction in self-report of depressive symptoms with a strong effect size (r = 0.78), that was maintained at follow-up (r = 0.86). Positive change was also obtained for informant reports of depressive symptoms from pre- to post-intervention, with a strong effect size (r = 0.7). Once again, this positive change was maintained at follow-up (r = 0.72).

CONCLUSIONS

The study suggested that behavioural activation may be a feasible and worthwhile approach to tackling depression in people with intellectual disabilities. However, a randomised controlled trial would be required to establish its effectiveness, with more sensitive measurement of change in activity.

Lenses and Lessons: Using three different research perspectives in early childhood education research

In contemporary Western research, collaboration is held in high esteem. This developing practice is chal¬lenging particularly for researchers who follow varying theoretical approaches. However although a challeng¬ing endeavour, when viewing the one data set with different lenses, there are various lessons that can be shared. A key aspect of this paper is involved researchers' different analytical perspectives in one data set to learn more about each other's research insights, rather than become instant expert in other's approaches. The interview data reported in this paper originates from a larger study researching parents' experience of using early child¬hood education and care (ECEC) in Australia. Here we analyse and report on two shared interview excerpts and use three different research lenses for analysis; phenomenographic study, conversational analysis and cul¬tural-historical theory. The finding of this paper demonstrates that applying different lenses provide different interpretations, including strengths, limitations and opportunities. In this paper we argue that collaborative research practices enhance our understanding of varying research approaches and the scope, quality, transla¬tion of research and the researchers' capacity are enhanced.

Increase in tumor-associated macrophages after antiangiogenic therapy is associated with poor survival among patients with recurrent glioblastoma

Antiangiogenic therapy is associated with increased radiographic responses in glioblastomas, but tumors invariably recur. Because tumor-associated macrophages have been shown to mediate escape from antiangiogenic therapy in preclinical models, we examined the role of macrophages in patients with recurrent glioblastoma. We compared autopsy brain specimens from 20 patients with recurrent glioblastoma who received antiangiogenic treatment and chemoradiation with 8 patients who received chemotherapy and/or radiotherapy without antiangiogenic therapy or no treatment. Tumor-associated macrophages were morphologically and phenotypically analyzed using flow cytometry and immunohistochemistry for CD68, CD14, CD163, and CD11b expression. Flow cytometry showed an increase in macrophages in the antiangiogenic-treated patients. Immunohistochemical analysis demonstrated an increase in CD68+ macrophages in the tumor bulk (P < .01) and infiltrative areas (P = .02) in antiangiogenic-treated patients. We also observed an increase in CD11b+ cells in the tumor bulk (P < .01) and an increase in CD163+ macrophages in infiltrative tumor (P = .02). Of note, an increased number of CD11b+ cells in bulk and infiltrative tumors (P = .05 and P = .05, respectively) correlated with poor overall survival among patients who first received antiangiogenic therapy at recurrence. In summary, recurrent glioblastomas showed an increased infiltration in myeloid populations in the tumor bulk and in the infiltrative regions after antiangiogenic therapy. Higher numbers of CD11b+ cells correlated with poor survival among these patients. These data suggest that tumor-associated macrophages may participate in escape from antiangiogenic therapy and may represent a potential biomarker of resistance and a potential therapeutic target in recurrent glioblastoma.

Abstract LB-339: Increase in tumor-associated macrophages (TAMs) after antiangiogenic therapy is associated with poor survival in recurrent glioblastoma (GBM) patients

Antiangiogenic therapy is associated with increased radiographic responses in glioblastomas (GBMs), but tumors invariably recur. Because tumor-associated macrophages (TAMs) have been shown to mediate escape from antiangiogenic therapy in preclinical models, we examined the role of TAMs in recurrent glioblastoma (rGBM) patients. We compared autopsy brain specimens from 20 rGBM patients who received antiangiogenic treatment and chemoradiation (AAT+) to 8 patients who received chemotherapy and/or radiotherapy without antiangiogenic therapy, or no treatment (AAT-). TAMs were morphologically and phenotypically analyzed using flow cytometry and immunohistochemistry (IHC) for CD68, CD14, CD163, and CD11b expression. Flow cytometry showed an increase in TAMs in the AAT+ patients. IHC analysis demonstrated an increase in CD68+ TAMs in the tumor bulk (p&lt;0.01) and infiltrative areas (p=0.02) in AAT+ patients. We also observed an increase in CD11b+ cells in the tumor bulk (p&lt;0.01) and an increase in CD163+ TAMs in infiltrative tumor (p=0.02). Of note, an increased number of CD11b+ cells in bulk and infiltrative tumor (p=0.05 and p=0.05, respectively) correlated with poor overall survival in patients who first received antiangiogenic therapy at recurrence. In summary, rGBMs showed an increased infiltration in myeloid populations in the tumor bulk and in the infiltrative regions after antiangiogenic therapy. Higher numbers of CD11b+ cells correlated with poor survival in rGBM patients. These data suggest that TAMs may participate in escape from antiangiogenic therapy and may represent a potential biomarker of resistance and a potential therapeutic target in rGBM.

Citation Format: Christine Lu-Emerson, Matija Snuderl, Nathaniel D. Kirkpatrick, Jermaine Goveia, Jennie Taylor, Christian Davidson, Yuhui Huang, Lars Riedemann, S. Percy Ivy, G. Dan Duda, Marek Ancukiewicz3, Scott R. Plotkin, Andrew Chi, Elizabeth R. Gerstner, April F. Eichler, Jorg Dietrich, Anat O. Stemmer-Rachamimov, Tracy T. Batchelor, Rakesh K. Jain. Increase in tumor-associated macrophages (TAMs) after antiangiogenic therapy is associated with poor survival in recurrent glioblastoma (GBM) patients. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-339. doi:10.1158/1538-7445.AM2013-LB-339

A phase I/II study of decitabine in combination with panitumumab in patients with wild-type (wt) KRAS metastatic colorectal cancer

PURPOSE

KRAS mutations are predictive of lack of response to monoclonal antibodies (mAb) against EGFR in metastatic colorectal cancer (mCRC). Most wild-type KRAS patients, however, are also resistant. Retrospective data suggest that EGFR silencing play a role in resistance to therapy. We conducted a study to evaluate the safety and efficacy of decitabine (a hypomethylating agent) in combination with panitumumab (mAb against EGFR) in mCRC patients.

EXPERIMENTAL DESIGN

20 patients with wild-type KRAS mCRC were included in this phase I/II study. Patients were treated with decitabine at 45 mg/m(2) IV over 2 h on day 1 and 15 and panitumumab 6 mg/kg IV over 1 h on day 8 and 22 every 28 days. Blood samples were collected at baseline, day 8, 15 and 22. Quantitative polymerase chain reaction was used to measure promoter-specific methylation in peripheral-blood cells (PBMCs).

RESULTS

The most common adverse events were grade 1-2 (rash and hypomagnesemia); 3 (16 %) patients had grade III-IV neutropenia including one patient with neutropenic fever. Two of 20 patients (10 %) had a partial response. Both had previously received cetuximab. Ten patients had stable disease (3 of them longer than 16 weeks). Decreased methylation of the MAGE promoter was not evidenced in PBMCs.

CONCLUSIONS

The combination of decitabine and panitumumab was well tolerated and showed activity in wild-type KRAS mCRC patients previously treated with cetuximab. Target modulation in surrogate tissues was not achieved and tumor biopsies were not available. Future studies evaluating hypomethylating agents in combination with EGFR mAb in patients with mCRC are warranted.

Abstract P6-07-24: Prognostic Tools in Early Breast Cancer: Predicting benefit of adjuvant chemotherapy

Introduction: Adjuvant chemotherapy (CT) in early breast cancer reduces the risk of mortality. However, absolute reductions in mortality can be small. For patient with low risk disease, prognostic tools such as ‘Adjuvant! Online’ and ‘Predict’ can be used to estimate the benefit of adjuvant chemotherapy. We compare the survival gains estimated using ‘Adjuvant! Online’ and ‘Predict’ in routine clinical practice, assessing the characteristics of patients in which ‘Adjuvant! Online’ and ‘Predict’ disagree.

Methods: In a retrospective study using the hospital electronic database, the clinical and pathological details of all patients with early breast cancer referred for adjuvant therapy at the Northern Ireland Cancer Centre in a 3 month period in 2011 were collected and were entered in to ‘Adjuvant! Online’ and ‘Predict’ to assess percentage benefit (absolute reduction in mortality at 10 years) from CT. We categorised patients into three prognostic groups: those where risk from CT outweighs benefit (&lt;2% predicted benefit), marginal benefit (2 to 5%) and significant benefit from CT (&gt;5%) We excluded patients with metastatic disease at presentation, DCIS, a second primary breast cancer or receiving neo-adjuvant treatment.

Results: Of the 250 patients identified, 61 (24.4%) fell in to different prognostic groups depending on whether ‘Adjuvant! Online’ or ‘Predict’ was used to calculate benefit from CT. In those in whom there was disagreement, ‘Adjuvant! Online’ suggested marginal or significant benefit in 75.4% of patients, compared to 55.7% using ‘Predict’. Nine patients had “major” comorbidities, which is weighted only in ‘Adjuvant! Online’, and were excluded in subsequent analysis. Of those without major comorbidities, ‘Adjuvant! Online’ offered at least 2% benefit in 85% of cases, and ‘Predict’ in only 58.3%. The majority (93.3%) of cases were ER positive, and node negative (85.0%). This difference was notable in women aged 65 or less, with 86.2% with &gt;2% benefit using ‘Adjuvant! Online’, compared to 55.1% using ‘Predict’. ‘Adjuvant! Online’ estimates of benefit were on average 3.7% higher for this age group. HER2 status had little impact, with similar recommendations using either ‘Adjuvant! Online’ or ‘Predict’.

Conclusions: This study highlights lack of concordance between two available online prognostic tools, notably in ER positive, node negative patients. For patients with a marginal benefit from adjuvant chemotherapy, care must be used when making adjuvant treatment decisions as other prognostic tools may be of help in this group of patients.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-07-24.

The single nucleotide polymorphism CRTh2 rs533116 is associated with allergic asthma and increased expression of CRTh2

BACKGROUND

CRTh2 (chemoattractant-receptor homologous molecule expressed on Th2 cells) is expressed by Th2 cells and other cells involved in allergic inflammation. Single nucleotide polymorphisms (SNPs) in CRTh2 (rs11571288, rs545659, rs634681) have been associated with various phenotypes of allergy in ethnically distinct populations. Here, we assessed the association between CRTh2 rs533116 and allergic asthma, expression of CRTh2 and Th2 cytokine production.

METHODS

CRTh2 rs533116 was genotyped in an ethnically diverse population (n = 1282). The proportion of cells expressing CRTh2 was determined in peripheral blood from subjects with allergic airways disease and controls as well as with in vitro differentiated Th2 cells. Receptor function was assessed by stimulating Th2 cells with the CRTh2-specific agonist 13,14-dihydro-15-keto-PGD(2) (DK-PGD(2) ) and measuring IL-4 and IL-13 by intracellular staining and ELISA.

RESULTS

CRTh2 rs533116 was associated with allergic asthma in White people (2.67 [1.09-6.55], P < 0.05), and expression of CRTh2 was higher in subjects with allergic airways disease compared to controls (P < 0.05). Among allergic individuals, the AA genotype was significantly associated with more eosinophils and higher expression of CRTh2 by both CD4(+) T cells and eosinophils (P < 0.05). In vitro, the AA genotype was associated with a higher proportion of CRTh2(+) cells during Th2 differentiation as well as more IL-4 and IL-13 expression following DK-PGD(2) stimulation (P < 0.05).

CONCLUSIONS

These findings show an association between CRTh2 rs533116 and allergic asthma and suggest this may be mediated by elevated expression of CRTh2, leading to higher numbers of circulating eosinophils and Th2 cytokine production.

The role of natural history collections in documenting species declines

Efforts to document the decline of extant populations require a historical record of previous occurrences. Natural history museums contain such information for most regions of the world, at least at a coarse spatial scale. Museum collections have been successfully used to analyse declines in a wide range of plants and animals, at spatial scales ranging from single localities to large biotic and political regions. Natural history museum collections, when properly analysed, can be an invaluable tool in documenting changes in biodiversity during the past century.

Allopregnanolone protects against dopamine-induced striatal damage after in vitro ischaemia via interaction at GABA A receptors

Sex steroid hormones, such as progesterone, have been shown to display neuroprotective properties after various models of central nervous system injury, including cerebral ischaemia, although the mechanism(s) of action remain largely undetermined. Allopregnanolone, an active progesterone metabolite, may explain some of the protective actions of progesterone. We utilised an in vitro model of ischaemia to evaluate the neuroprotective potential of allopregnanolone and examine its interaction at the GABA(A) receptor, which is hypothesised to be its main neuroprotective mechanism. In adult male mouse coronal caudate slices exposed to oxygen glucose deprivation (OGD), we measured aspects of OGD-induced dopamine release, which is neurotoxic during ischaemia, using fast cyclic voltammetry and also assessed tissue viability. The GABA(A) agonist, muscimol, displayed a neuroprotective profile in terms of delaying the OGD-evoked dopamine efflux (P < 0.05) and reducing the amount of dopamine released after OGD (P < 0.05). Allopregnanolone, at a concentration of 10(-6)  m, also displayed a neuroprotective profile because it significantly reduced the amount of dopamine efflux (P < 0.05) and reduced the loss of viable tissue after OGD compared to slices exposed to vehicle during OGD (P < 0.05). However, the effect of 10(-6)  m allopregnanolone on dopamine efflux was prevented in the presence of bicuculline, a competitive GABA(A) receptor antagonist. These results describe the use of an in vitro model of ischaemia with respect to determining that allopregnanolone is neuroprotective during the acute phase of ischaemia, and also demonstrate that such actions are dependent, at least in part, upon interaction at the GABA(A) receptor.

Effect of antiangiogenic therapy on tumor-associated macrophages in recurrent glioblastoma

2010

Background: Antiangiogenic therapy is associated with increased radiographic responses in glioblastoma (GBM), but tumors invariably recur. Tumor associated macrophages (TAMs) have been proposed as a mechanism of resistance to anti-angiogenic therapy in preclinical models. To examine the role of TAMs in recurrent GBM, we analyzed autopsy specimens from patients with or without history of antiangiogenic therapy. Methods: We compared autopsy brain specimens from 17 recurrent GBM patients who received anti-angiogenic treatment and chemoradiation (AAT+) to 7 patients who received chemotherapy and/or radiotherapy without anti-angiogenic therapy, or no treatment (AAT-). TAMs were morphologically and phenotypically identified with flow cytometry and immunohistochemistry (IHC) with CD68, CD11b, CD14, and CD163 markers. All specimens were obtained from the Department of Pathology at Massachusetts General Hospital and clinical information gained through review of the patients’ records. Results: Using flow cytometry, we observed an increase in CD11b+CD14+ cells in the AAT+ patients compared to AAT- patients. Using IHC analysis, we observed a significant increase in CD68+ macrophages in the tumor bulk (p<0.01) and infiltrative areas (p<0.05) in AAT+ versus AAT- patients. We also observed a significant increase in CD11b+ myeloid cells in the tumor bulk (p<0.01) and a significant increase in CD163+ cells in the infiltrative areas (p<0.05) in the AAT+ group. Finally, we noted a trend toward an increase in CD163+ cells in the tumor bulk (p=0.087) in the AAT+ versus the AAT- patients. Conclusions: Patients with recurrent GBM after antiangiogenic therapy showed a significant increase in CD68+ TAMs and in CD11b+ cells in the tumor bulk. Additionally, antiangiogenic treatment induced an increase in CD68+ and CD163+ TAMs in the infiltrative region. These data indicate that TAMs may participate in escape from antiangiogenic therapy and may represent a future therapeutic target in recurrent GBM.