Distinct genomic landscapes of gastroesophageal adenocarcinoma depending on PD-L1 expression identify mutations in RAS-MAPK pathway and TP53 as potential predictors of immunotherapy efficacy.

BACKGROUND: The impact of molecular alterations on programmed death-ligand 1 (PD-L1) combined positive score (CPS) is not well studied in gastroesophageal adenocarcinomas (GEAs). We aimed to characterize genomic features of tumors with different CPSs in GEAs. PATIENTS AND METHODS: Genomic alterations of 2518 GEAs were compared in three groups (PD-L1 CPS ≥ 10, high; CPS = 1-9, intermediate; CPS < 1, low) using next-generation sequencing. We assessed the impact of gene mutations on the efficacy of immune checkpoint inhibitors (ICIs) and tumor immune environment based on the Memorial Sloan Kettering Cancer Center and The Cancer Genome Atlas databases. RESULTS: High, intermediate, and low CPSs were seen in 18%, 54% and 28% of GEAs, respectively. PD-L1 positivity was less prevalent in women and in tissues derived from metastatic sites. PD-L1 CPS was positively associated with mismatch repair deficiency/microsatellite instability-high, but independent of tumor mutation burden distribution. Tumors with mutations in KRAS, TP53, and RAS-mitogen-activated protein kinase (MAPK) pathway were associated with higher PD-L1 CPSs in the mismatch repair proficiency and microsatellite stability (pMMR&MSS) subgroup. Patients with RAS-MAPK pathway alterations had longer overall survival (OS) from ICIs compared to wildtype (WT) patients [27 versus 13 months, hazard ratio (HR) = 0.36, 95% confidence interval (CI): 0.19-0.7, P = 0.016] and a similar trend was observed in the MSS subgroup (P = 0.11). In contrast, patients with TP53 mutations had worse OS from ICIs compared to TP53-WT patients in the MSS subgroup (5 versus 21 months, HR = 2.39, 95% CI: 1.24-4.61, P = 0.016). CONCLUSIONS: This is the largest study to investigate the distinct genomic landscapes of GEAs with different PD-L1 CPSs. Our data may provide novel insights for patient selection using mutations in TP53 and RAS-MAPK pathway and for the development of rational combination immunotherapies in GEAs.

Predictive Value of Noncontrast Head CT with Negative Findings in the Emergency Department Setting.

BACKGROUND AND PURPOSE: Noncontrast head CTs are routinely acquired for patients with neurologic symptoms in the emergency department setting. Anecdotally, noncontrast head CTs performed in patients with prior negative findings with the same clinical indication are of low diagnostic yield. We hypothesized that the rate of acute findings in noncontrast head CTs performed in patients with a preceding study with negative findings would be lower compared with patients being imaged for the first time. MATERIALS AND METHODS: We retrospectively evaluated patients in the emergency department setting who underwent noncontrast head CTs at our institution during a 4-year period, recording whether the patient had undergone a prior noncontrast head CT, the clinical indication for the examination, and the examination outcome. Positive findings on examinations were defined as those that showed any intracranial abnormality that would necessitate a change in acute management, such as acute hemorrhage, hydrocephalus, herniation, or interval worsening of a prior finding. RESULTS: During the study period, 8160 patients in the emergency department setting underwent a total of 9593 noncontrast head CTs; 88.2% (7198/8160) had a single examination, and 11.8% (962/8160) had at least 1 repeat examination. The baseline positive rate of the "nonrepeat" group was 4.3% (308/7198). The 911 patients in the "repeat" group with negative findings on a baseline/first CT had a total of 1359 repeat noncontrast head CTs during the study period. The rate of positive findings for these repeat examinations was 1.8% (25/1359), significantly lower than the 4.3% baseline rate (P < .001). Of the repeat examinations that had positive findings, 80% (20/25) had a study indication that was discordant with that of the prior examination, compared with only 44% (593/1334) of the repeat examinations that had negative findings (P < .001). CONCLUSIONS: In a retrospective observational study based on approximately 10,000 examinations, we found that serial noncontrast head CT examinations in patients with prior negative findings with the same study indication are less likely to have positive findings compared with first-time examinations or examinations with a new indication. This finding suggests a negative predictive value of a prior noncontrast head CT examination with negative findings with the same clinical indication.

Diffusion Characteristics of Pediatric Diffuse Midline Gliomas with Histone H3-K27M Mutation Using Apparent Diffusion Coefficient Histogram Analysis.

BACKGROUND AND PURPOSE: Diffuse midline gliomas with histone H3 K27M mutation are biologically aggressive tumors with poor prognosis defined as a new diagnostic entity in the 2016 World Health Organization Classification of Tumors of the Central Nervous System. There are no qualitative imaging differences (enhancement, border, or central necrosis) between histone H3 wildtype and H3 K27M-mutant diffuse midline gliomas. Herein, we evaluated the utility of diffusion-weighted imaging to distinguish H3 K27M-mutant from histone H3 wildtype diffuse midline gliomas. MATERIALS AND METHODS: We identified 31 pediatric patients (younger than 21 years of age) with diffuse gliomas centered in midline structures that had undergone assessment for histone H3 K27M mutation. We measured ADC within these tumors using a voxel-based 3D whole-tumor measurement method. RESULTS: Our cohort included 18 infratentorial and 13 supratentorial diffuse gliomas centered in midline structures. Twenty-three (74%) tumors carried H3-K27M mutations. There was no difference in ADC histogram parameters (mean, median, minimum, maximum, percentiles) between mutant and wild-type tumors. Subgroup analysis based on tumor location also did not identify a difference in histogram descriptive statistics. Patients who survived <1 year after diagnosis had lower median ADC (1.10 × 10-3mm2/s; 95% CI, 0.90-1.30) compared with patients who survived >1 year (1.46 × 10-3mm2/s; 95% CI, 1.19-1.67; P < .06). Average ADC values for diffuse midline gliomas were 1.28 × 10-3mm2/s (95% CI, 1.21-1.34) and 0.86 × 10-3mm2/s (95% CI, 0.69-1.01) for hemispheric glioblastomas with P < .05. CONCLUSIONS: Although no statistically significant difference in diffusion characteristics was found between H3-K27M mutant and H3 wildtype diffuse midline gliomas, lower diffusivity corresponds to a lower survival rate at 1 year after diagnosis. These findings can have an impact on the anticipated clinical course for this patient population and offer providers and families guidance on clinical outcomes.

Hybrid 3D/2D Convolutional Neural Network for Hemorrhage Evaluation on Head CT.

BACKGROUND AND PURPOSE: Convolutional neural networks are a powerful technology for image recognition. This study evaluates a convolutional neural network optimized for the detection and quantification of intraparenchymal, epidural/subdural, and subarachnoid hemorrhages on noncontrast CT. MATERIALS AND METHODS: This study was performed in 2 phases. First, a training cohort of all NCCTs acquired at a single institution between January 1, 2017, and July 31, 2017, was used to develop and cross-validate a custom hybrid 3D/2D mask ROI-based convolutional neural network architecture for hemorrhage evaluation. Second, the trained network was applied prospectively to all NCCTs ordered from the emergency department between February 1, 2018, and February 28, 2018, in an automated inference pipeline. Hemorrhage-detection accuracy, area under the curve, sensitivity, specificity, positive predictive value, and negative predictive value were assessed for full and balanced datasets and were further stratified by hemorrhage type and size. Quantification was assessed by the Dice score coefficient and the Pearson correlation. RESULTS: A 10,159-examination training cohort (512,598 images; 901/8.1% hemorrhages) and an 862-examination test cohort (23,668 images; 82/12% hemorrhages) were used in this study. Accuracy, area under the curve, sensitivity, specificity, positive predictive value, and negative-predictive value for hemorrhage detection were 0.975, 0.983, 0.971, 0.975, 0.793, and 0.997 on training cohort cross-validation and 0.970, 0.981, 0.951, 0.973, 0.829, and 0.993 for the prospective test set. Dice scores for intraparenchymal hemorrhage, epidural/subdural hemorrhage, and SAH were 0.931, 0.863, and 0.772, respectively. CONCLUSIONS: A customized deep learning tool is accurate in the detection and quantification of hemorrhage on NCCT. Demonstrated high performance on prospective NCCTs ordered from the emergency department suggests the clinical viability of the proposed deep learning tool.

Deep-Learning Convolutional Neural Networks Accurately Classify Genetic Mutations in Gliomas.

BACKGROUND AND PURPOSE: The World Health Organization has recently placed new emphasis on the integration of genetic information for gliomas. While tissue sampling remains the criterion standard, noninvasive imaging techniques may provide complimentary insight into clinically relevant genetic mutations. Our aim was to train a convolutional neural network to independently predict underlying molecular genetic mutation status in gliomas with high accuracy and identify the most predictive imaging features for each mutation. MATERIALS AND METHODS: MR imaging data and molecular information were retrospectively obtained from The Cancer Imaging Archives for 259 patients with either low- or high-grade gliomas. A convolutional neural network was trained to classify isocitrate dehydrogenase 1 (IDH1) mutation status, 1p/19q codeletion, and O6-methylguanine-DNA methyltransferase (MGMT) promotor methylation status. Principal component analysis of the final convolutional neural network layer was used to extract the key imaging features critical for successful classification. RESULTS: Classification had high accuracy: IDH1 mutation status, 94%; 1p/19q codeletion, 92%; and MGMT promotor methylation status, 83%. Each genetic category was also associated with distinctive imaging features such as definition of tumor margins, T1 and FLAIR suppression, extent of edema, extent of necrosis, and textural features. CONCLUSIONS: Our results indicate that for The Cancer Imaging Archives dataset, machine-learning approaches allow classification of individual genetic mutations of both low- and high-grade gliomas. We show that relevant MR imaging features acquired from an added dimensionality-reduction technique demonstrate that neural networks are capable of learning key imaging components without prior feature selection or human-directed training.

Entorhinal Cortex: Antemortem Cortical Thickness and Postmortem Neurofibrillary Tangles and Amyloid Pathology.

BACKGROUND AND PURPOSE: The entorhinal cortex, a critical gateway between the neocortex and hippocampus, is one of the earliest regions affected by Alzheimer disease-associated neurofibrillary tangle pathology. Although our prior work has automatically delineated an MR imaging-based measure of the entorhinal cortex, whether antemortem entorhinal cortex thickness is associated with postmortem tangle burden within the entorhinal cortex is still unknown. Our objective was to evaluate the relationship between antemortem MRI measures of entorhinal cortex thickness and postmortem neuropathological measures. MATERIALS AND METHODS: We evaluated 50 participants from the Rush Memory and Aging Project with antemortem structural T1-weighted MR imaging and postmortem neuropathologic assessments. Here, we focused on thickness within the entorhinal cortex as anatomically defined by our previously developed MR imaging parcellation system (Desikan-Killiany Atlas in FreeSurfer). Using linear regression, we evaluated the association between entorhinal cortex thickness and tangles and amyloid-ß load within the entorhinal cortex and medial temporal and neocortical regions. RESULTS: We found a significant relationship between antemortem entorhinal cortex thickness and entorhinal cortex (P = .006) and medial temporal lobe tangles (P = .002); we found no relationship between entorhinal cortex thickness and entorhinal cortex (P = .09) and medial temporal lobe amyloid-ß (P = .09). We also found a significant association between entorhinal cortex thickness and cortical tangles (P = .003) and amyloid-ß (P = .01). We found no relationship between parahippocampal gyrus thickness and entorhinal cortex (P = .31) and medial temporal lobe tangles (P = .051). CONCLUSIONS: Our findings indicate that entorhinal cortex-associated in vivo cortical thinning may represent a marker of postmortem medial temporal and neocortical Alzheimer disease pathology.

Fluoroscopic sentinel events in neuroendovascular procedures: how to screen, prevent, and address occurrence.

Radiation-induced skin injury during fluoroscopic procedures has been recently addressed by The Joint Commission, which defined prolonged fluoroscopy resulting in a cumulative peak skin dose of ≥15 Gy to a single field as a sentinel event (FSE). Neuroendovascular procedures can be associated with a high radiation skin dose and present risks such as potential FSEs. Managing these risks is the responsibility of the interventional neuroradiologist. In this review, we discuss hospital policies needed for screening and preventing FSEs, methods for minimizing radiation-induced skin injury, and actions necessary to address potential FSEs once they have occurred.

Endoscopic balloon sphincter dilation (sphincteroplasty) versus sphincterotomy for common bile duct stones.

BACKGROUND: Endoscopic balloon dilation was introduced as an alternative to endoscopic sphincterotomy to preserve the sphincter of Oddi and avoid undesirable effects due to an incompetent sphincter. Endoscopic balloon dilation has been largely abandoned by USA endoscopists due to increased risks of pancreatitis noted in one multicentre trial, but is still practiced in parts of Asia and Europe. OBJECTIVES: To assess the beneficial and harmful effects of endoscopic balloon dilation versus endoscopic sphincterotomy in the management of common bile duct stones. SEARCH STRATEGY: We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, and EMBASE until January 2004. We hand searched Gastrointestinal Endoscopy (1983-2002), read through bibliographies of all included randomised clinical trials, and contacted all primary authors regarding missed randomised trials. SELECTION CRITERIA: Randomised clinical trials comparing endoscopic balloon dilation versus endoscopic sphincterotomy in removal of common bile duct stones irrespective of publication status, language, or blinding. DATA COLLECTION AND ANALYSIS: Data collection was done by two independent authors for decisions on study inclusion, data abstraction, and quality assessment. When there was a non-resolvable discrepancy, the third author made the final decision. Analysis was run with RevMan Analysis. MAIN RESULTS: Fifteen randomised trials met our inclusion criteria (1768 participants). Less than half of the trials reported adequate methods of randomisation and only two trials used blinded outcome assessment. Endoscopic balloon dilation is statistically less successful for stone removal (relative risk (RR) 0.90, 95% confidence interval (CI) 0.84 to 0.97), requires higher rates of mechanical lithotripsy (RR 1.34, 95% CI 1.08 to 1.66), and carries a higher risk of pancreatitis (RR 1.96, 95% CI 1.34 to 2.89). Conversely, endoscopic balloon dilation has statistically significant lower rates of bleeding. When a fixed-effect model is applied endoscopic balloon dilation leads to significantly less short-term infection and long-term infection. There was no statistically significant difference with regards to mortality, perforation, or total short-term complications. AUTHORS' CONCLUSIONS: Endoscopic balloon dilation is slightly less successful than endoscopic sphincterotomy in stone extraction and more risky regarding pancreatitis. However, endoscopic balloon dilation seems to have a clinical role in patients who have coagulopathy, who are at risk for infection, and possibly in those who are older.

NO synthase 2 (NOS2) deletion promotes multiple pathologies in a mouse model of Alzheimer's disease.

Alzheimer's disease is characterized by two primary pathological features: amyloid plaques and neurofibrillary tangles. The interconnection between amyloid and tau aggregates is of intense interest, but mouse models have yet to reveal a direct interrelationship. We now show that NO may be a key factor that connects amyloid and tau pathologies. Genetic removal of NO synthase 2 in mice expressing mutated amyloid precursor protein results in pathological hyperphosphorylation of mouse tau, its redistribution to the somatodendritic compartment in cortical and hippocampal neurons, and aggregate formation. Lack of NO synthase 2 in the amyloid precursor protein Swedish mutant mouse increased insoluble beta-amyloid peptide levels, neuronal degeneration, caspase-3 activation, and tau cleavage, suggesting that NO acts at a junction point between beta-amyloid peptides, caspase activation, and tau aggregation.

Local carboplatin delivery and tissue distribution in livers after radiofrequency ablation.

This study investigated the local drug pharmacokinetics of intralesional drug delivery after radiofrequency ablation of the liver. We hypothesized that the tissue architecture damaged by the ablation process facilitates the drug penetration in the liver and potentially enlarges the therapeutic margin in the local treatment of cancer. The delivery rate and tissue distribution of carboplatin, an anticancer agent, released from poly(D,L-lactide-co-glycolide) implants into rat livers after radiofrequency ablation were quantified by atomic absorption spectroscopy. Results showed that carboplatin clearance through blood perfusion was significantly slower in the ablated livers, leading to a more extensive tissue retention and distribution of the drug. The concentration of Pt at the implant-tissue interface ranged from 234 to 1440 microg Pt/(g liver) in the ablated livers over 144 h versus 56 to 177 microg Pt/(g liver) in the normal tissue. The maximum penetration distance at which Pt level reached above 6 microg/g (calculated based on a reported IC90 value for carboplatin) was 8-10 mm and 4-6 mm in ablated and normal liver, respectively. Histological analysis of the necrotic lesions showed widespread destruction of tissue structure and vasculature, supporting the initial hypothesis. This study demonstrated that intralesional drug delivery could provide a sustained, elevated concentration of anticancer drug at the ablation boundary that has the potential to eliminate residual cancer cells surviving radiofrequency ablation.

Patterns of proton pump inhibitor use in clinical practice.

BACKGROUND: Little is known about differences between gastroenterologists and primary care physicians in their patterns of prescribing proton pump inhibitors. SUBJECTS AND METHODS: A survey of practicing primary care physicians from the American Board of Medical Specialties and practicing gastroenterologists from the American Gastroenterological Association was conducted by facsimile. The survey instrument consisted of 13 questions about pharmacokinetics and administration of proton pump inhibitors. RESULTS: The overall response rate was 15% (491 of 3273), and 80% (395 of 491) of respondents were nontrainee gastroenterologists or primary care physicians. Approximately 90% (n = 355) of eligible respondents correctly identified proton pump inhibitors as inhibitors of H+,K+-adenosinetriphosphatase. Proton pump inhibitors were prescribed by 80% (n = 314) of each group for reflux esophagitis. They were prescribed by 67% (122 of 182) of gastroenterologists and 27% (58 of 213) of primary care physicians to prevent ulcers induced by nonsteroidal anti-inflammatory drugs (P <0.001). And they were prescribed by 40% (n = 73) of gastroenterologists and 16% (n = 34) of primary care physicians for uncomplicated heartburn (P <0.001). Proton pump inhibitors were prescribed before a meal by 95% (n = 173) of gastroenterologists and 33% (n = 70) of primary care physicians (P <0.001). Nearly 99% (n = 391) of respondents agreed that proton pump inhibitors were safe, but only 15% (n = 59) thought they should be available without prescription. CONCLUSION: Our survey suggests that the use of proton pump inhibitors differs between gastroenterologists and primary care physicians. Furthermore, although most physicians believe that proton pump inhibitors are safe, few believe that they should be available without a prescription.

Mothers with HIV/AIDS and their children: disclosure and guardianship issues.

For many mothers living with HIV/AIDS, whether, when, and how to disclose their HIV diagnosis to their children and arranging for future care are important although agonizing issues. Due to the increasing number of children who lose their mothers to AIDS and the dearth of empirical information about them, these issues are increasingly important to research. This study of 188 HIV-positive mothers and their 267 children of minor age in New York City revealed that only half the mothers had disclosed their HIV diagnosis to at least one of their children and only 57% had made formal plans for the children's care. As expected, older children were more likely to be informed than younger children. Contrary to some previous research, maternal disclosure was not related to ethnicity, advanced illness, improved psychological well-being, or greater or more satisfying social support resources. Implications for future research and provision of services to this group of women are discussed.

Loracarbef versus clarithromycin in children with acute otitis media with effusion.

Two multicenter, randomized, single-masked, parallel-group studies compared loracarbef and clarithromycin with regard to efficacy, tolerability, and patient acceptance. Three hundred thirty-four children aged 6 months to 3 years with acute otitis media with effusion received loracarbef (15 mg/kg) or clarithromycin (7.5 mg/kg) orally twice daily for 10 days. Patients were assessed for the presence of the diagnostic signs and symptoms of otitis media with effusion by physical examination and pneumatic otoscopy at 48 hours pretreatment, 3 to 5 days after initiation of treatment, 0 to 3 days after the final dose (posttreatment), and 14 to 21 days later (termination). Symptoms were assigned numeric values. Symptomatic response was assessed at the posttherapy and termination visits. Tolerability was determined by assessing adverse events, and a patient acceptance survey was completed by each patient's caregiver. The combined results of these 2 studies showed that the efficacy and tolerability of loracarbef were comparable to those of clarithromycin. Adverse events were reported by 46.4% of loracarbef patients and 41.0% of clarithromycin patients, with no statistically significant difference between groups. In the intent-to-treat analysis, 57.9% of loracarbef patients were cured at the termination of the study, compared with 55.7% of clarithromycin patients. Improvement was seen in 4.1% of loracarbef patients and 2.7% of clarithromycin patients. Results of the patient acceptance survey showed a clear preference for loracarbef over clarithromycin. Difficulties with administration of treatment were reported by 36.3% of clarithromycin caregivers, compared with 7.8% of loracarbef caregivers (P < 0.001). A desire to stop treatment was reported by 23.8% of clarithromycin caregivers, compared with 7.8% of loracarbef caregivers (P < 0.001). Taste and texture issues were most frequently cited as reasons for nonacceptance.

Sonographic sign of intermittent dilatation of the renal collecting system in 10 patients with vesicoureteral reflux.

PURPOSE: Renal sonography is an accepted primary imaging modality for evaluating the pediatric urinary tract. We report a new sonographic finding associated with vesicoureteral reflux (VUR). METHODS: Ten patients underwent sonographic evaluation of the kidneys and were noted to have intermittent renal collecting system dilatation that expanded and contracted during real-time scanning. These patients were further evaluated with voiding cystourethrography. RESULTS: All 10 patients were proven to have VUR on the side of the sonographic abnormality. Four patients had bilateral VUR for a total of 14 refluxing renal units. Of these 14 renal units, 1 was sonographically normal. Five of the 14 renal units had grade V VUR that required surgical reimplantation of the ureter. CONCLUSIONS: This new finding of intermittent renal collecting system dilatation may become an important predictor of VUR. The finding warrants further evaluation even when detected in patients not suspected of having VUR who are undergoing renal sonography for other reasons.

Results of a program to improve the process of inpatient care of adult asthmatics.

OBJECTIVE: To assess the effectiveness of a program to improve care of adult patients hospitalized for asthma. DESIGN: Retrospective analysis of patient and house staff education, patterns of medication use, spacer use, peak flowmeter use, and length of stay before and after team intervention. SETTING: A 960-bed teaching hospital in New York City. PATIENTS: All patients admitted to the hospital with a primary diagnosis of acute asthma exacerbation for 2 separate similar calendar periods, 1 year apart, before and after program intervention. We excluded patients who were hospitalized for less than 24 h or greater than 10 days. The preintervention group comprised 61 patients and the postintervention group 65 patients, well matched in their demographic characteristics and severity of disease. INTERVENTIONS: Using a team approach, we analyzed the process of inpatient treatment of asthma exacerbation, identified root causes for quality deficiency, and implemented specific improvements in the process. These included dedicated nurses who focused on the education of care providers and patients, a personalized attending-intern educational approach, and improvement in the supply and delivery of spacers, peak flowmeters, and medications to the patients. RESULTS: There was a significant increase in use of spacers, peak flowmeters, and inhaled corticosteroids. Systemic corticosteroid and methylxanthine use declined. Length of stay was reduced without increasing early hospital readmission rates. CONCLUSIONS: This program improved the treatment process of adults hospitalized for asthma.

Enhancement of female esophageal and tracheoesophageal speech.

Qi [J. Acoust. Soc. Am. 88, 1228-1235 (1990)] has demonstrated that (1) linear predictive (LP) methods can be used to separate vocal tract transfer functions from source functions of vowels produced by alaryngeal talkers and that (2) vowels synthesized with reconstructed transfer functions and totally synthetic voicing excitation sources have improved source-related properties over those present in the original vowels. Here, an extension of this work which is directed to the general goal of developing systems (devices) to enhance the quality of alaryngeal speech is reported. The specific goal of the present project was to determine whether speech, i.e., words spoken by female esophageal and tracheoesophageal talkers, could be enhanced by means of LP-based analysis and synthesis methods. Words spoken by four female alaryngeal talkers were analyzed and synthesized. A perceptual evaluation was completed to permit the quality of the synthetic and the original words to be compared. Listeners generally preferred to listen to the synthesized words, indicating that alaryngeal speech enhancement was accomplished.