A practical approach to ineffective esophageal motility.

BACKGROUND AND PURPOSE: Ineffective esophageal motility (IEM) is the most frequently diagnosed esophageal motility abnormality and characterized by diminished esophageal peristaltic vigor and frequent weak, absent, and/or fragmented peristalsis on high-resolution esophageal manometry. Despite its commonplace occurrence, this condition can often provoke uncertainty for both patients and clinicians. Although the diagnostic criteria used to define this condition has generally become more stringent over time, it is unclear whether the updated criteria result in a more precise clinical diagnosis. While IEM is often implicated with symptoms of dysphagia and gastroesophageal reflux disease, the strength of these associations remains unclear. In this review, we share a practical approach to IEM highlighting its definition and evolution over time, commonly associated clinical symptoms, and important management and treatment considerations. We also share the significance of this condition in patients undergoing evaluation for anti-reflux surgery and consideration for lung transplantation.

Unraveling molecular advancements in chordoma tumorigenesis and treatment response: a review of scientific discoveries and clinical implications.

Chordomas are tumors thought to originate from notochordal remnants that occur in midline structures from the cloves of the skull base to the sacrum. In adults, the most common location is the sacrum, followed by the clivus and then mobile spine, while in children a clival origin is most common. Most chordomas are slow growing. Clinical presentation of chordomas tend to occur late, with local invasion and large size often complicating surgical intervention. Radiation therapy with protons has been proven to be an effective adjuvant therapy. Unfortunately, few adjuvant systemic treatments have demonstrated significant effectiveness, and chordomas tend to recur despite intensive multimodal care. However, insight into the molecular underpinnings of chordomas may guide novel therapeutic approaches including selection for immune and molecular therapies, individualized prognostication of outcomes, and real-time noninvasive assessment of disease burden and evolution. At the genomic level, elevated levels of brachyury stemming from duplications and mutations resulting in altered transcriptional regulation may introduce druggable targets for new surgical adjuncts. Transcriptome and epigenome profiling have revealed promoter- and enhancer-dependent mechanisms of protein regulation, which may influence therapeutic response and long-term disease history. Continued scientific and clinical advancements may offer further opportunities for treatment of chordomas. Single-cell transcriptome profiling has further provided insight into the heterogeneous molecular pathways contributing to chordoma propagation. New technologies such as spatial transcriptomics and emerging biochemical analytes such as cell-free DNA have further augmented the surgeon-clinician's armamentarium by facilitating detailed characterization of intra- and intertumoral biology while also demonstrating promise for point-of-care tumor quantitation and assessment. Recent and ongoing clinical trials highlight accelerating interest to translate laboratory breakthroughs in chordoma biology and immunology into clinical care. In this review, the authors dissect the landmark studies exploring the molecular pathogenesis of chordoma. Incorporating this into an outline of ongoing clinical trials and discussion of emerging technologies, the authors aimed to summarize recent advancements in understanding chordoma pathogenesis and how neurosurgical care of chordomas may be augmented by improvements in adjunctive treatments.

Post-bariatric Surgery Changes in Secondary Esophageal Motility and Distensibility Parameters.

INTRODUCTION: Despite the increasing number of bariatric procedures over the recent years, the physiological changes in secondary esophageal motility and distensibility parameters after surgery remain unknown. METHODS: This is a retrospective, single-center cohort study comparing esophageal planimetry and gastroesophageal junction (GEJ) distensibility in post-bariatric surgery patients (Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and conversion/revisional patients (DH)) and native-anatomy patients with obesity (NAC). Distensibility refers to the area achieved with a certain amount of pressure, and secondary peristalsis represents the esophageal response to an intended obstruction. Patients with pre-surgical dysmotility symptoms were excluded from the study. RESULTS: From November 2018 to January 2023, 167 patients were evaluated and eligible for this study (RYGB = 87, SG = 33, NAC = 22, DH = 25). In NAC cohort, 17/22 (77%) patients presented normal motility patterns compared to 35/87 (40%) RYGB, 12/33 (36%) SG, and 5/25 (20%) DH (p < 0.05 for all comparisons). The most common abnormal motility pattern for all three bariatric cohorts was absent contractions. DH patients generally had the highest mean maximum distensibility index averages, followed by SG, RYGB, and NAC. CONCLUSION: Bariatric surgery affects esophageal and GEJ physiology, and it is associated with higher rates of secondary dysmotility. DH patients have even higher rates of dysmotility. Further studies assessing clinical data and their correlation with manometric and pH-metric findings are needed.

Development of a model to identify patients who do not need oesophageal biopsies when eosinophilic oesophagitis is suspected.

BACKGROUND: Predictive models for eosinophilic oesophagitis (EoE) may not fully rule in the diagnosis. AIM: To develop a reverse model that predicts against EoE to eliminate the need for oesophageal biopsies. METHODS: In this two-centre study, a predictive model was developed (Mayo Clinic) and validated (University of North Carolina [UNC]). Cross-sectional data from consecutive adult patients without prior EoE who underwent upper enoscopy with oesophageal biopsies were used. EoE cases had ≥15 eosinophils/high-power field while controls had no eosinophils. Data were collected on patient clinical and endoscopic features. Multiple variable logistic regression was used to identify predictors of non-EoE status while maintaining specificity ≥95%. A secondary model was developed to predict against the need for endoscopy in patients suspected of having EoE without alarm symptoms. RESULTS: The Mayo and UNC cohorts consisted of 345 (EoE = 94, non-EoE = 251) and 297 patients (EoE = 84, non-EoE = 213), respectively. A primary model based on clinical and endoscopic features predicted against EoE with c-statistic 0.92 (95% CI: 0.88-0.96), specificity 95%, and sensitivity 65%. This model was validated (UNC) with c-statistic 0.87 (95% CI: 0.82-0.92). A simplified scoring system was created and a threshold of ≥12 points excluded EoE with 95% specificity and 50% sensitivity. A secondary model based on clinical characteristics alone predicted against EoE with c-statistic 0.86 (95% CI: 0.82-0.90), specificity 95% and sensitivity 39% and validated (UNC) with c-statistic 0.78 (95% CI: 0.71-0.85). CONCLUSION: A simplified scoring system accurately identified a group of patients with a low likelihood of EoE where unnecessary oesophageal biopsies can be avoided, potentially resulting in resource and cost savings.

Clinical Efficacy of ONC201 in H3K27M-Mutant Diffuse Midline Gliomas Is Driven by Disruption of Integrated Metabolic and Epigenetic Pathways.

Patients with H3K27M-mutant diffuse midline glioma (DMG) have no proven effective therapies. ONC201 has recently demonstrated efficacy in these patients, but the mechanism behind this finding remains unknown. We assessed clinical outcomes, tumor sequencing, and tissue/cerebrospinal fluid (CSF) correlate samples from patients treated in two completed multisite clinical studies. Patients treated with ONC201 following initial radiation but prior to recurrence demonstrated a median overall survival of 21.7 months, whereas those treated after recurrence had a median overall survival of 9.3 months. Radiographic response was associated with increased expression of key tricarboxylic acid cycle-related genes in baseline tumor sequencing. ONC201 treatment increased 2-hydroxyglutarate levels in cultured H3K27M-DMG cells and patient CSF samples. This corresponded with increases in repressive H3K27me3 in vitro and in human tumors accompanied by epigenetic downregulation of cell cycle regulation and neuroglial differentiation genes. Overall, ONC201 demonstrates efficacy in H3K27M-DMG by disrupting integrated metabolic and epigenetic pathways and reversing pathognomonic H3K27me3 reduction. SIGNIFICANCE: The clinical, radiographic, and molecular analyses included in this study demonstrate the efficacy of ONC201 in H3K27M-mutant DMG and support ONC201 as the first monotherapy to improve outcomes in H3K27M-mutant DMG beyond radiation. Mechanistically, ONC201 disrupts integrated metabolic and epigenetic pathways and reverses pathognomonic H3K27me3 reduction. This article is featured in Selected Articles from This Issue, p. 2293.

Performance of an Artificial Intelligence Model for Recognition and Quantitation of Histologic Features of Eosinophilic Esophagitis on Biopsy Samples.

We have developed an artificial intelligence (AI)-based digital pathology model for the evaluation of histologic features related to eosinophilic esophagitis (EoE). In this study, we evaluated the performance of our AI model in a cohort of pediatric and adult patients for histologic features included in the Eosinophilic Esophagitis Histologic Scoring System (EoEHSS). We collected a total of 203 esophageal biopsy samples from patients with mucosal eosinophilia of any degree (91 adult and 112 pediatric patients) and 10 normal controls from a prospectively maintained database. All cases were assessed by a specialized gastrointestinal (GI) pathologist for features in the EoEHSS at the time of original diagnosis and rescored by a central GI pathologist (R.K.M.). We subsequently analyzed whole-slide image digital slides using a supervised AI model operating in a cloud-based, deep learning AI platform (Aiforia Technologies) for peak eosinophil count (PEC) and several histopathologic features in the EoEHSS. The correlation and interobserver agreement between the AI model and pathologists (Pearson correlation coefficient [rs] = 0.89 and intraclass correlation coefficient [ICC] = 0.87 vs original pathologist; rs = 0.91 and ICC = 0.83 vs central pathologist) were similar to the correlation and interobserver agreement between pathologists for PEC (rs = 0.88 and ICC = 0.91) and broadly similar to those for most other histologic features in the EoEHSS. The AI model also accurately identified PEC of >15 eosinophils/high-power field by the original pathologist (area under the curve [AUC] = 0.98) and central pathologist (AUC = 0.98) and had similar AUCs for the presence of EoE-related endoscopic features to pathologists' assessment. Average eosinophils per epithelial unit area had similar performance compared to AI high-power field-based analysis. Our newly developed AI model can accurately identify, quantify, and score several of the main histopathologic features in the EoE spectrum, with agreement regarding EoEHSS scoring which was similar to that seen among GI pathologists.

Eosinophilic Esophagitis Histologic Scoring System: Correlation with Histologic, Endoscopic, and Symptomatic Disease and Clinical Use.

BACKGROUND: The eosinophilic esophagitis histologic scoring system (EoEHSS) was developed to enhance the diagnostic standard of peak eosinophil count (PEC) in evaluating disease activity in EoE. AIMS: (1) Correlate the EoEHSS and PEC to measures of symptomatic and endoscopic disease activity, (2) Correlate EoEHSS grade and stage subcomponents to clinical, radiology, and endoscopic markers of fibrotic disease, (3) Evaluate EoEHSS remission in asymptomatic patients with PEC < 15 eosinophils per high powered field (eos/hpf). METHODS: Secondary analysis of prospective cohort data of 22 patients with EoE that underwent dietary therapy and endoscopy at 3 time points. Active disease was defined by EoEHSS grade or stage > 0.125, symptomatic disease by EoE symptom activity index > 20, endoscopic disease by endoscopic reference score > 2, and histologic disease by PEC ≥ 15 eos/hpf. EoEHSS remission was defined by esophageal inflammation (EI) grade of 0-1, EI stage of 0, total grade ≤ 3, and total stage ≤ 3. RESULTS: EoEHSS grade and stage did not correlate with symptomatic disease but did with endoscopic and histologic disease. PEC showed similar correlation pattern. Abnormal grade and stage had strong sensitivity (87-100%) but poor specificity (11-36%) to detect symptomatic, endoscopic, and histologic disease activity. Lamina propria fibrosis was evaluated in 36% of biopsies and did not correlate with minimum esophageal diameter. Out of 14 patients who were in complete symptomatic, endoscopic, and histologic remission, 8 met criteria for EoEHSS remission. CONCLUSION: The positive and negative correlations of EoEHSS to specific measures of symptomatic, histologic, and endoscopic activity suggest that it provides complementary information in EoE.

Turnkey algorithmic approach for the evaluation of gastroesophageal reflux disease after bariatric surgery.

Bariatric surgeries are often complicated by de-novo gastroesophageal reflux disease (GERD) or worsening of pre-existing GERD. The growing rates of obesity and bariatric surgeries worldwide are paralleled by an increase in the number of patients requiring post-surgical GERD evaluation. However, there is currently no standardized approach for the assessment of GERD in these patients. In this review, we delineate the relationship between GERD and the most common bariatric surgeries: sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB), with a focus on pathophysiology, objective assessment, and underlying anatomical and motility disturbances. We suggest a stepwise algorithm to help diagnose GERD after SG and RYGB, determine the underlying cause, and guide the management and treatment.

Use of the Esophageal Sponge in Directing Food Reintroduction in Eosinophilic Esophagitis.

BACKGROUND & AIMS: Dietary therapy is successful in eosinophilic esophagitis (EoE) but requires multiple upper endoscopies. The aim of this study was to determine if food reintroduction in EoE can be directed by minimally-invasive esophageal sponge cytology. METHODS: In this prospective non-blinded trial, 22 responders to 6-food elimination diets underwent sequential food reintroduction guided by esophageal sponge cytology. Foods were reintroduced followed by unsedated esophageal sponge cytology assessment. A food trigger was defined by sponge cytology peak eosinophil count of ≥15 eos/high-powered field (hpf). Symptoms (EoE symptom activity index [EEsAI]), endoscopic score (EoE endoscopic reference score [EREFS]), and biopsy histology (peak eosinophil count) were collected pre-dietary therapy and post-dietary therapy, and then 4 weeks post food reintroduction. RESULTS: The EEsAI and EREFS were similar post-dietary therapy to post-food reintroduction: 12.0 (interquartile range [IQR], 0.0-27.0) vs 16.5 (IQR, 9.0-28.8) (P = .265) and 1.5 (IQR, 0.2-3.0) vs 1.0 (IQR, 0.0-2.0) (P = .185). However, the peak eosinophil count was increased post-food reintroduction compared with post-dietary therapy: 20.0 (IQR, 5.0-51.5) vs 2.0 (IQR, 1.0-4.0) (P < .001), suggesting a failure of identification of all food triggers. The peak eosinophil count was lower post-food reintroduction compared with pre-dietary therapy: 20.0 (IQR, 5.0-51.5) vs 52.0 (IQR, 30.8-76.2) (P = .008). At the post food reintroduction evaluation, sponge cytology and biopsy histology were in agreement in 59% (13/22) of cases using a cutoff of <15 eos/hpf and 68% (15/22) of cases using a cutoff of <6 eos/hpf. CONCLUSIONS: In the first study to evaluate a non-endoscopic technique in the clinical management of EoE, the esophageal sponge was moderately successful at guiding food reintroduction in EoE dietary responders in the outpatient setting. CLINICALTRIALS: gov, Number NCT02599558.

Development and technical validation of an artificial intelligence model for quantitative analysis of histopathologic features of eosinophilic esophagitis.

Background: In an attempt to provide quantitative, reproducible, and standardized analyses in cases of eosinophilic esophagitis (EoE), we have developed an artificial intelligence (AI) digital pathology model for the evaluation of histologic features in the EoE/esophageal eosinophilia spectrum. Here, we describe the development and technical validation of this novel AI tool. Methods: A total of 10 726 objects and 56.2 mm2 of semantic segmentation areas were annotated on whole-slide images, utilizing a cloud-based, deep learning artificial intelligence platform (Aiforia Technologies, Helsinki, Finland). Our training set consisted of 40 carefully selected digitized esophageal biopsy slides which contained the full spectrum of changes typically seen in the setting of esophageal eosinophilia, ranging from normal mucosa to severe abnormalities with regard to each specific features included in our model. A subset of cases was reserved as independent "test sets" in order to assess the validity of the AI model outside the training set. Five specialized experienced gastrointestinal pathologists scored each feature blindly and independently of each other and of AI model results. Results: The performance of the AI model for all cell type features was similar/non-inferior to that of our group of GI pathologists (F1-scores: 94.5-94.8 for AI vs human and 92.6-96.0 for human vs human). Segmentation area features were rated for accuracy using the following scale: 1. "perfect or nearly perfect" (95%-100%, no significant errors), 2. "very good" (80%-95%, only minor errors), 3. "good" (70%-80%, significant errors but still captures the feature well), 4. "insufficient" (less than 70%, significant errors compromising feature recognition). Rating scores for tissue (1.01), spongiosis (1.15), basal layer (1.05), surface layer (1.04), lamina propria (1.15), and collagen (1.11) were in the "very good" to "perfect or nearly perfect" range, while degranulation (2.23) was rated between "good" and "very good". Conclusion: Our newly developed AI-based tool showed an excellent performance (non-inferior to a group of experienced GI pathologists) for the recognition of various histologic features in the EoE/esophageal mucosal eosinophilia spectrum. This tool represents an important step in creating an accurate and reproducible method for semi-automated quantitative analysis to be used in the evaluation of esophageal biopsies in this clinical context.

Predictors of histologic response to dietary therapy in eosinophilic oesophagitis.

BACKGROUND: Dietary therapy successfully treats eosinophilic oesophagitis (EoE), but limited data exist on predictors of patient response. AIMS: To determine response rates and to identify predictors of histologic response to elimination diets in adults with EoE METHODS: This was a retrospective, single-centre study of adults with PPI-refractory EoE undergoing dietary therapy with six food elimination diet (SFED) or extended six food elimination diet (ExSFED) in an outpatient setting from January 2012 to January 2019. Patient demographics, radiologic and endoscopic findings, endoscopic reference (EREF) scores, histology and symptoms were evaluated before and after food elimination. Histologic response was assessed via tissue obtained from endoscopically-guided biopsy or Cytosponge. Dietary therapy adherence was assessed via structured phone interview. Multivariable logistic regression analysis was performed to identify predictors of dietary response. RESULTS: We included 68 patients, of whom 62% had a histologic response to dietary therapy (81% to SFED, 19% to ExSFED). Median duration of follow-up was 45 months (IQR, 34-53 months). On multivariable analysis, higher pre-SFED EREF score was the only variable associated with dietary non-response (OR 0.07, 95% CI 0.49, 0.98; p = 0.04). CONCLUSIONS: In adults with EoE, histologic dietary non-response to SFED was associated with a higher pre-SFED EREF score, suggesting that fixed structural disease may predict dietary non-response. Our additional observations of poor correlation between symptomatic and histologic flares, and identification of ExSFED responders, suggest that histologic confirmation should be sought before committing patients to lifelong dietary changes. We also recommend the consideration of restricting legumes and corn in SFED non-responders as ExSFED detected additional dietary responders.

Histologic response to steroids in eosinophilic esophagitis is dependent on delivery compound.

Topical steroids are commonly used in treatment of eosinophilic esophagitis (EoE), but currently there is lack of data to clarify most effective regimen. We aimed to study the achievement of histologic remission using the same dose of budesonide in two different delivery formulations. Patients with established EoE treated with pharmacy compounded budesonide capsule or budesonide Rincinol gel (both 3 mg twice daily) were studied retrospectively. Those with pre-treatment and post-treatment histologic assessment were included with main endpoint being histologic remission. 103 patients (62 gel, 41 capsule) were included, with higher rate of histologic remission with gel (84 vs. 59%, P=0.004). A subset of patients in both groups had lack of steroid response (<50% drop in eosinophils) (15% for gel, 32% for capsule). Formulation/delivery vehicle of steroid treatments to esophageal mucosa in EoE appears important for treatment efficacy, with budesonide gel having higher likelihood of histologic remission compared to budesonide capsules in our population. A truly steroid refractory group appears likely in our population. Larger, prospective studies may help clarify best regimen of topical steroids in EoE and may work to identify patients likely to benefit from alternative therapies.

Expanding Access to CNS-TAP: Design, Development, and Initial Use of a Complex Precision Health Specialty Web App for Neuro-Oncology.

This paper offers a case study to demonstrate how a complex scoring model tool called CNS-TAP, originally created by a neuro-oncology team at one institution, was upgraded and made accessible to a wider audience. In the Results and Discussion, many issues of web app design, development, and sustainability are covered. Overall, we chart a path to expand access to many unique software tools created and needed by today's medical specialists.

Cell-Free Tumor DNA (cf-tDNA) Liquid Biopsy: Current Methods and Use in Brain Tumor Immunotherapy.

Gliomas are tumors derived from mutations in glial brain cells. Gliomas cause significant morbidity and mortality and development of precision diagnostics and novel targeted immunotherapies are critically important. Radiographic imaging is the most common technique to diagnose and track response to treatment, but is an imperfect tool. Imaging does not provide molecular information, which is becoming critically important for identifying targeted immunotherapies and monitoring tumor evolution. Furthermore, immunotherapy induced inflammation can masquerade as tumor progression in images (pseudoprogression) and confound clinical decision making. More recently, circulating cell free tumor DNA (cf-tDNA) has been investigated as a promising biomarker for minimally invasive glioma diagnosis and disease monitoring. cf-tDNA is shed by gliomas into surrounding biofluids (e.g. cerebrospinal fluid and plasma) and, if precisely quantified, might provide a quantitative measure of tumor burden to help resolve pseudoprogression. cf-tDNA can also identify tumor genetic mutations to help guide targeted therapies. However, due to low concentrations of cf-tDNA, recovery and analysis remains challenging. Plasma cf-tDNA typically represents <1% of total cf-DNA due to the blood-brain barrier, limiting their usefulness in practice and motivating the development and use of highly sensitive and specific detection methods. This mini review summarizes the current and future trends of various approaches for cf-tDNA detection and analysis, including new methods that promise more rapid, lower-cost, and accessible diagnostics. We also review the most recent clinical case studies for longitudinal disease monitoring and highlight focus areas, such as novel accurate detection methodologies, as critical research priorities to enable translation to clinic.

Serial H3K27M cell-free tumor DNA (cf-tDNA) tracking predicts ONC201 treatment response and progression in diffuse midline glioma.

BACKGROUND: Diffuse Midline Glioma (DMG) with the H3K27M mutation is a lethal childhood brain cancer, with patients rarely surviving 2 years from diagnosis. METHODS: We conducted a multi-site Phase 1 trial of the imipridone ONC201 for children with H3K27M-mutant glioma (NCT03416530). Patients enrolled on Arm D of the trial (n = 24) underwent serial lumbar puncture for cell-free tumor DNA (cf-tDNA) analysis and patients on all arms at the University of Michigan underwent serial plasma collection. We performed digital droplet polymerase chain reaction (ddPCR) analysis of cf-tDNA samples and compared variant allele fraction (VAF) to radiographic change (maximal 2D tumor area on MRI). RESULTS: Change in H3.3K27M VAF over time ("VAF delta") correlated with prolonged PFS in both CSF and plasma samples. Nonrecurrent patients that had a decrease in CSF VAF displayed a longer progression free survival (P = .0042). Decrease in plasma VAF displayed a similar trend (P = .085). VAF "spikes" (increase of at least 25%) preceded tumor progression in 8/16 cases (50%) in plasma and 5/11 cases (45.4%) in CSF. In individual cases, early reduction in H3K27M VAF predicted long-term clinical response (>1 year) to ONC201, and did not increase in cases of later-defined pseudo-progression. CONCLUSION: Our work demonstrates the feasibility and potential utility of serial cf-tDNA in both plasma and CSF of DMG patients to supplement radiographic monitoring. Patterns of change in H3K27M VAF over time demonstrate clinical utility in terms of predicting progression and sustained response and possible differentiation of pseudo-progression and pseudo-response.

Variability in endoscopic assessment of Nissen fundoplication wrap integrity and hiatus herniation.

BACKGROUND: Upper endoscopy (EGD) is frequently performed in patients with esophageal complaints following anti-reflux surgery such as fundoplication. Endoscopic evaluation of fundoplication wrap integrity can be challenging. Our primary aim in this pilot study was to evaluate the accuracy and confidence of assessing Nissen fundoplication integrity and hiatus herniation among gastroenterology (GI) fellows, subspecialists, and foregut surgeons. METHODS: Five variations of post-Nissen fundoplication anatomy were included in a survey of 20 sets of EGD images that was completed by GI fellows, general GI attendings, esophagologists, and foregut surgeons. Accuracy, diagnostic confidence, and inter-rater agreement across providers were evaluated. RESULTS: There were 31 respondents in the final cohort. Confidence in pre-survey diagnostics significantly differed by provider type (mean confidence out of 5 was 1.8 for GI fellows, 2.7 for general GI attendings, 3.6 for esophagologists, and 3.6 for foregut surgeons, P = 0.01). The mean overall accuracy was 45.9%, which significantly differed by provider type with the lowest rate among GI fellows (37%) and highest among esophagologists (53%; P = 0.01). The accuracy was highest among esophagologists across all wrap integrity variations. Inter-rater agreement was low across wrap integrity variations (Krippendorf's alpha <0.30), indicating low to no agreement between providers. CONCLUSION: In this multi-center survey study, GI fellows had the lowest accuracy and confidence in assessing EGD images after Nissen fundoplication, whereas esophagologists had the highest. Diagnostic confidence varied considerably and inter-rater agreement was poor. These findings suggest experience may improve confidence, but highlight the need to improve the evaluation of fundoplication wraps.

Proton Pump Inhibitor Prescribing and Monitoring Patterns Among Gastroenterology Practitioners.

GOALS: The aim was to quantify proton pump inhibitor (PPI) practice habits among gastroenterology (GI) practitioners. BACKGROUND: Reports of side effects have prompted patients and practitioners alike to discontinue PPI use. Emerging evidence-based literature on PPI risks and safety seek to guide practitioners, but the impact of this literature on PPI prescribing patterns has not been evaluated. STUDY: We performed an anonymous online survey of US GI practitioners across 6 academic and community affiliated medical centers. Demographic data including practice type and number of weekly gastroesophageal reflux disease patients seen were obtained. Survey questions evaluated practitioners' monitoring for PPI side effects, dose adjustments, and sources of information about PPI risks. RESULTS: The survey response rate was 60% (256/429). The majority of respondents were male (169, 66%) attending physicians (178, 70%) practicing general GI (63, 25%). There were 92 (36%) respondents who reported testing for PPI side effects at least once a year. Most respondents (143, 56%) reported discontinuing PPIs at least 50% of the time because of patients' concerns about PPI side effects. The majority of respondents reported getting their information regarding PPI safety from published journals (239, 98%) as well as colleagues (222, 91%). CONCLUSIONS: Despite best available evidence suggesting safety of long-term PPI use without routine monitoring, stopping PPIs and monitoring for potential side effects occurs frequently, even within a cohort of mostly academic GI practitioners. Alternative strategies are needed to improve adherence to best practices, especially since gastroenterologists often serve as PPI experts.

Panobinostat penetrates the blood-brain barrier and achieves effective brain concentrations in a murine model.

PURPOSE: Panobinostat, an orally bioavailable pan-HDAC inhibitor, has demonstrated potent activity in multiple malignancies, including pediatric brain tumors such as DIPG, with increased activity against H3K27M mutant cell lines. Given limited evidence regarding the CNS penetration of panobinostat, we sought to characterize its BBB penetration in a murine model. METHODS: Panobinostat 15 mg/kg was administered IV to 12 CD-1 female mice. At specified time points, mice were euthanized, blood samples were collected, and brains were removed. LC-MS was performed to quantify panobinostat concentrations. Cmax and AUC were estimated and correlated with previously published pharmacokinetic analyses and reports of IC-50 values in DIPG cell lines. RESULTS: Mean panobinostat plasma concentrations (ng/mL) were 27.3 ± 2.5 at 1 h, 7.56 ± 1.8 at 2 h, 1.48 ± 0.56 at 4 h, and 2.33 ± 1.18 at 7 h. Mean panobinostat brain concentrations (ng/g) were 60.5 ± 6.1 at 1 h, 42.9 ± 5.4 at 2 h, 33.2 ± 6.1 at 4 h, and 28.1 ± 4.3 at 7 h. Brain-to-plasma ratio at 1 h was 2.22 and the brain to plasma AUC ratio was 2.63. Based on the published human pharmacokinetic data, the anticipated Cmax in humans is expected to be significantly higher than the IC-50 identified in DIPG models. CONCLUSION: It is expected that panobinostat would be effective in CNS tumors where the IC-50 is in the low nanomolar range. Thus, our data demonstrate panobinostat crosses the BBB and achieves concentrations above the IC-50 for DIPG and other brain tumors and should be explored further for clinical efficacy.