Biochemical Relapse-Free Survival in Post-Prostatectomy Patients Receiving 18F-Fluciclovine-Guided Prostate Bed Only Radiation: Post-Hoc Analysis of a Prospective Randomized Trial

PURPOSE/OBJECTIVE(S)

Whole pelvis (WP) radiation therapy (XRT) significantly improved biochemical relapse free survival (bRFS) compared to prostate-bed (PB)-only XRT in RTOG 0534, yet increased toxicity and was performed in an era prior to PET staging (Pollack et al, Lancet, 2022). Separately, 18F-fluciclovine PET/CT (PET)-guided post-prostatectomy XRT demonstrated improved bRFS compared to XRT guided by conventional imaging alone. We hypothesized that patients whose decisions were changed from whole pelvic XRT to PB-only XRT after PET imaging would have bRFS that was (a) not significantly different than patients initially planned for PB-only XRT, and (b) significantly improved over patients planned for WP XRT without PET guidance.

MATERIALS/METHODS

We conducted a post-hoc analysis of a prospective, randomized, single-institution trial comparing conventional (Arm A) v. PET-guided (Arm B) post-prostatectomy XRT. For patients randomized to Arm B, pre-PET treatment field decisions were recorded, and post-fluciclovine fields were rigidly defined per protocol: pN0 patients with no pelvic or extrapelvic PET uptake received PB-only XRT. Three- and four-year bRFS were compared in patients initially planned for WP with change to PB-only XRT [Arm B (WP→PB)] v Arm B patients initially planned for PB-only with final XRT to PB-only [Arm B(PB→PB)] & Arm A patients treated with whole pelvic XRT [Arm A(WP)] using Z test and log-rank test. Demographics were compared using Chi-square test, Fisher's exact test, or ANOVA as appropriate.

RESULTS

We identified 10 Arm B (WP→PB), 31 Arm B (PB→PB), and 25 Arm A (WP) patients. Androgen deprivation was used in 50.0% of Arm B (WP→PB) and 3.2% of Arm B (PB→PB) patients, p<0.01. Mean pre-XRT PSA was significantly higher (1.56 v 0.32 ng/mL, respectively, p<0.01) in Arm B (WP→PB) v Arm B (PB→PB) patients, however, there was no significant difference in extracapsular extension (p = 1.00), seminal vesical invasion (p = 1.00), Gleason score ≥8 (p = 0.58) or margin positivity (p = 0.73) between cohorts. Three- and four-year bRFS was 80% in Arm B (WP→PB) & 87.4% in Arm B (PB→PB), p = 0.47, respectively. Arm A (WP) patients had significantly worse three- (35.2%) and four-year (13.2%) bRFS compared to Arm B (WP→PB), p<0.01.

CONCLUSION

Patients initially planned for WP XRT whose treatment field decisions were changed to PB-only XRT after PET guidance had, in this post-hoc analysis, (a) relapse rates not significantly different than patients initially planned for PB-only XRT and (b) improved relapse rates over patients treated with WP XRT without PET guidance. PET-guided volume de-escalation in selected patients may be one approach to mitigating excess toxicity seen with WP XRT without compromising outcomes and warrants further exploration.

Rapid Unpaired CBCT-Based Synthetic CT for CBCT-Guided Adaptive Radiotherapy

PURPOSE/OBJECTIVE(S)

Quantitative cone beam CT (CBCT) is the foundation for image-guided radiation therapy, improving treatment setup, tumor delineation and dose calculation. However, CBCT images suffer from severe artifacts, limiting clinical utility. Deep learning can overcome these limitations, boosting radiographic and dosimetric quality critical for online adaptive radiotherapy (ART). We hypothesize adapted contrastive unpaired translation (CUT), a recent method for image-to-image translation of photographic images, can improve CBCT quality while reducing compute time, demonstrating utility for ART.

MATERIALS/METHODS

Same-day CBCT and quality assurance CT (QACT) images acquired from 79 patients receiving proton therapy for prostate cancer between 2019 and 2020 at a single institution were retrospectively collected. QACT images were acquired for quality assurance in accordance with institutional policy. Seventy-nine patients yielded 102 non-contrast CBCT-QACT image sets. Each QACT image was rigidly registered to the corresponding CBCT and resampled to 1 × 1 × 2 mm to establish uniform voxel size and spacing. CBCT images were randomly shuffled prior to input to the CUT model for unsupervised training and QACT-quality synthetic CT images were generated as outputs. We compared mean absolute error (MAE), structural similarity index measure (SSIM), and Fréchet inception distance (FID) against same-day QACT.

RESULTS

MAE, SSIM, and FID were compared for the CycleGAN and CUT data relative to input QACT and are reported as the mean across five-fold cross-validation ± standard error. CUT achieved superior performance in MAE (19.5 ± 3.9 HU vs. cycleGAN 47.1 ± 25.4) and FID (31.5 ± 6.6 vs cycleGAN 75.9 ± 41.3). MAE indicates pixel-level correspondence to QACT HU intensity values, making the synthetic outputs of CUT useful for dose calculations during ART. FID further demonstrates perceptual visual similarity. SSIM for CycleGAN (0.7 ± 0.2) and CUT (0.8 ± 0.0) were similar, indicating acceptable reproducibility of global structure. CUT was faster and lighter than CycleGAN. CycleGAN contained a total of 28,286,000 parameters; CUT contained 14,703,000, approximately half that of CycleGAN. As a result, CycleGAN computes on a single CT image slice over 0.33s while CUT requires just 0.18s.

CONCLUSION

The contrastive method investigated here was demonstrated to be faster and more accurate than CycleGAN, requiring fewer networks and parameters to achieve superior performance. We demonstrated anatomic boundary preservation and HU fidelity superior to cycleGAN while significantly reducing compute time. We plan to investigate the use of these synthetic CT images in automated segmentation prior to exploration of CUT in a prospective setting.

Association of Radiation Facility Volume with Overall Survival in Patients with Very High-Risk Prostate Cancer Treated with Radiation and Androgen Deprivation Therapy

PURPOSE/OBJECTIVE(S)

Studies suggest an association of treatment at high volume facilities with improved survival in cancer patients receiving surgery or radiation therapy. This association has not been studied in patients with very high-risk prostate cancer, who are treated using a multimodality approach that often requires specialized care with advanced diagnostic imaging, complex radiotherapeutic planning, and multidrug antiandrogen regimens. We used the National Cancer Database (NCDB) to study the association of radiation treatment facility volume (FV) with overall survival (OS).

MATERIALS/METHODS

We selected for patients with very high risk, localized prostate cancer by NCCN criteria (cT3b-T4, primary Gleason pattern 5, >4 cores with grade group 4-5, and/or 2-3 high risk features). We included patients who received hormone therapy with either external beam radiation to a dose of ≥60 Gy or external beam radiation to a dose of ≥45 Gy combined with brachytherapy. Association of FV with OS was evaluated through a bias-adjusted log-rank test to identify the optimal cut point of FV for dichotomization. Kaplan-Meier curves were used to study the association of binary FV with overall survival (OS) with and without IPTW (inverse probability treatment weighting) balancing the following confounders: age, race, median income, education, insurance, academic treatment facility, Charlson comorbidity score, T stage, PSA, Gleason score, total radiation dose, year of diagnosis, and patient distance from treatment facility. Cox proportional hazards model was built using backward variable selection strategy (α of 0.05 for removal).

RESULTS

We identified 25,219 very high-risk prostate cancer patients by NCCN criteria (median follow up 57.36 months; 95% CI 56.67 - 58.09) diagnosed between 2004 and 2015. High FV (n = 6,438) was associated with better OS on univariable analysis (hazard ratio [HR] = 0.81; 95% confidence interval [CI] 0.77 - 0.86; p < 0.001) and multivariable analysis (HR = 0.89; 95% CI 0.84 - 0.95; p < 0.001). Other factors associated with improved OS on multivariable analysis included younger age, non-white/black race, higher income, private insurance, academic/research treatment facility, lower comorbidity, lower T-stage, lower PSA, and lower Gleason score. After IPTW adjustment, high FV remained associated with better OS (HR = 0.90; 95% CI 0.85 - 0.95; p < 0.001).

CONCLUSION

Patients with NCCN very high-risk prostate cancer treated at a radiation facility with high case volume had better OS than patients treated at a facility with low volume, after adjustment for confounders. This may suggest that for very high-risk patients, outcomes may be improved by the expertise and optimal multidisciplinary care that typically accompany high facility treatment volume.

Utilization of Radical Prostatectomy vs. Radiation Therapy for Gleason Grade Group 5 Prostate Cancer before and after USPSTF Grade D Recommendation against Prostate-Specific Antigen Screening in 2012

PURPOSE/OBJECTIVE(S)

The 2012 United States Preventive Services Task Force (USPSTF) Grade D recommendation against prostate-specific antigen (PSA) screening has resulted in a shift to higher-stage prostate cancer (PC) at diagnosis. While incidence of low-risk prostate cancer has declined, more men are diagnosed with high-risk disease, and multimodal treatment is often required. The impact of this epidemiologic shift on practice patterns, specifically radical prostatectomy (RP) versus definitive radiation therapy (RT), for men with localized PC at high risk of recurrence is unknown. Herein, we evaluate the utilization of RP versus RT in the United States for Gleason grade group 5 (GG5) prostate cancer before and after 2012.

MATERIALS/METHODS

We identified 34,011 men with localized GG5 PC treated with (1) RP or (2) RT plus androgen deprivation therapy (ADT) between 2004 and 2017 in the National Cancer Database. We excluded those who were clinically node-positive, had metastatic disease, or received chemotherapy or palliative-intent treatment. Chi-square was used to compare the relative use of RP and RT before versus after January 1, 2012, corresponding to the year of USPSTF recommendation against PSA screening. Annual use of RP versus RT from 2004 to 2017 was compared in academic and non-academic centers using Cochran-Armitage test for trend. Joinpoint regression assessed if 2012 was significant for inflection of crude rates of RP. Finally, we modeled the effect of treatment year (i.e., 2012-2017 versus 2004-2011) on use of RP using multivariable logistic regression. Sensitivity analysis tested an interaction term for facility type (i.e., academic versus community). Tests were two-sided with a 0.05 level of significance.

RESULTS

Of the eligible men, 10,745 (31.6%) had T3-T4 disease. Between 2004 and 2011, 36.5% (n = 5,483) underwent RP; between 2012 and 2017, 42.3% (n = 8,034) underwent RP (p = .02). Across all centers, use of RP increased from 31% to 41% (p for trend <.001). In academic centers, use of RP increased from 32% to 44% (p for trend <.001); in community centers, use of RP increased from 30% to 39% (p for trend <.001). 2012 was associated with significant inflection for increase in RP use in all centers. On multivariable analysis, there was an increased odds of receiving RP after 2012 (adjusted OR 1.34, 95% CI 1.28-1.40, p<.001). No differential effect by facility type was observed (p = .15).

CONCLUSION

Utilization of RP for GG5 PC has significantly increased in the United States over the past decade, particularly after the USPSTF Grade D recommendation against PSA screening in 2012. It remains unknown whether oncologic or functional outcomes may be compromised in this group of high-risk men, many of whom require post-prostatectomy RT and/or ADT. While historically rare, prospective comparison of RP versus RT+ADT for GG5 PC may be helpful given the evolving epidemiology of localized PC.

Disparities in Time to Prostate Cancer Treatment Initiation before and after the Affordable Care Act

PURPOSE/OBJECTIVE(S)

Delayed access to care may contribute to disparities in prostate cancer (PCa). The Affordable Care Act (ACA) aimed at increasing access and reducing healthcare disparities, but its impact on timely treatment initiation for men with PCa is unknown.

MATERIALS/METHODS

Men with intermediate- and high-risk PCa diagnosed 2010-2016 and treated with curative surgery or radiotherapy were identified in the National Cancer Database. Multivariable logistic regression modeled the effect of race and insurance type on treatment delay >180 days after diagnosis to start of surgery, radiotherapy, or hormonal therapy. Cochran-Armitage test measured annual trends in delays, and join point regression assessed if 2014, the year the ACA became fully operationalized, was significant for inflection in crude rates of major delays.

RESULTS

Of 422,506 eligible men, 18,720 (4.4%) experienced >180-day delay in treatment initiation. Compared to White patients, Black (OR 1.79, 95% CI 1.72-1.87, p<.001) and Hispanic (OR 1.37, 95% CI 1.28-1.48, p<.001) patients had higher odds of delay. These disparities persisted when analyzing only patients treated after 2014 or for patients who had Medicare or Private insurance. Compared to uninsured patients, those with Medicaid had no difference in odds of delay (OR 0.94, 95% CI 0.84-1.06, p = .31), while those with private insurance (OR 0.57, 95% CI 0.52-0.63, p<.001) or Medicare (OR 0.64, 95% CI 0.58-0.70, p<.001) had lower odds of delay. These disparities persisted when analyzing only patients treated after 2014. Mean time to treatment significantly increased from 2010 to 2016 across all racial/ethnic groups (trend p<.001); 2014 was associated with a significant inflection for increase in rates of major delays.

CONCLUSION

The impact of race and insurance status were independently associated with longer delays to PCa treatment in the US. These disparities were unaffected by implementation of the ACA. In fact, implementation of ACA was associated with increased delays in treatment initiation for all men, regardless of race. As the epidemiology of newly diagnosed prostate cancer in the United States continues to shift due to tempered screening and the COVID pandemic, further work will be needed to increase equity in prostate cancer care.

Accuracy of Femoral Tunnel Placement between Anteromedial and Anterolateral Visualisation Portals in Anterior Cruciate Ligament Reconstruction - Outcomes of a CT based Cross-Sectional Study

Introduction

Anatomical femoral tunnel placement is critical for anterior cruciate ligament reconstruction (ACLR). Tunnel placement may vary with different surgical techniques. The aim of this study was to compare the accuracy of femoral tunnel placement between the Anteromedial (AM) and Anterolateral (AL) visualisation portals on post-operative CT scans among a cohort of ACLR patients.

Materials and methods

This cross-sectional study was conducted from January 2018 to March 2020 after obtaining ethics clearance. Patients who went for arthroscopic ACLR in our institute were divided into an AM (group 1) and an AL (group 2) based on the visualisation portal for creating the femoral tunnel and a 3D CT scan was done. The femoral tunnel position was calculated in deep to shallow and high to low direction using the Bernard Hertel grid. Femoral tunnel angle was measured in the 2D coronal image. Statistical analysis was done with the data collected.

Results

Fifty patients with an average age of 26.36 (18-55) years ±7.216 SD were enrolled in the study. In this study, the AM technique was significantly more accurate (p<0.01) than the AL technique in terms of femoral tunnel angle. Furthermore, the deep to the shallow position was significantly (p= 0.018) closer to normative values, as determined by the chi-square test. The chances of error in tunnel angle in femoral condyle are 2.6 times greater in the AL technique (minimal clinical difference).

Conclusion

To conclude, in ACLR the anteromedial visualisation portal can facilitate accurate femoral tunnel placement compared to the anterolateral visualisation portal.

Prediction of plan adaptation in head and neck cancer proton therapy using clinical, radiographic, and dosimetric features

PURPOSE

Because proton head and neck (HN) treatments are sensitive to anatomical changes, plan adaptation (re-plan) during the treatment course is needed for a significant portion of patients. We aim to predict re-plan at plan review stage for HN proton therapy with a neural network (NN) model trained with patients' dosimetric and clinical features. The model can serve as a valuable tool for planners to assess the probability of needing to revise the current plan.

METHODS AND MATERIALS

Mean beam dose heterogeneity index (BHI), defined as the ratio of the maximum beam dose to the prescription dose, plan robustness features (clinical target volume (CTV), V100 changes, and V100 > 95% passing rates in 21 robust evaluation scenarios), as well as clinical features (e.g., age, tumor site, and surgery/chemotherapy status) were gathered from 171 patients treated at our proton center in 2020, with a median age of 64 and stages from I-IVc across 13 HN sites. Statistical analyses of dosimetric parameters and clinical features were conducted between re-plan and no-replan groups. A NN was trained and tested using these features. Receiver operating characteristic (ROC) analysis was conducted to evaluate the performance of the prediction model. A sensitivity analysis was done to determine feature importance.

RESULTS

Mean BHI in the re-plan group was significantly higher than the no-replan group (p < .01). Tumor site (p < .01), chemotherapy status (p < .01), and surgery status (p < .01) were significantly correlated to re-plan. The model had sensitivities/specificities of 75.0%/77.4%, respectively, and an area under the ROC curve of .855.

CONCLUSION

There are several dosimetric and clinical features that correlate to re-plans, and NNs trained with these features can be used to predict HN re-plans, which can be used to reduce re-plan rate by improving plan quality.

Integration of Point-of-Care Ultrasound Education Into the Internal Medicine Core Clerkship Experience

Point-of-care ultrasound (POCUS) is becoming an essential skill for internists. To date, there are no professional guidelines for how POCUS skills should be taught to medical students. A panel of POCUS experts from seven academic medical centers in the United States was convened to describe the components of independently developed IM clerkship POCUS training programs, identify areas of similarity and difference, and propose recommendations for alignment.

Serial measurement of global longitudinal strain among women with breast cancer treated with proton radiation therapy

Background

Conventional photon radiotherapy (RT) for breast cancer is associated with reduction in global longitudinal strain (GLS), an increase in both troponin and N-terminal pro-B type natriuretic peptide (NT-proBNP), and incident heart failure. The cardiac radiation exposure with proton-RT is reduced and, thus may be associated with less cardiotoxicity.

Objectives

To test the effect of proton-RT on GLS, troponin and NT-proBNP.

Methods

A prospective observational single center study of 69 women being treated with proton-RT for breast cancer. Serial measurements of GLS, high-sensitivity cardiac troponin-I (hs-cTnI), and NT-proBNP were performed at pre-specified intervals (pre proton-RT, 4 weeks after completion of proton-RT and again at 2 months post proton-RT).

Results

The mean age was 46±11 years, BMI was 25.6±5.2 kg/m2, 32% had hypertension and mean radiation dose to the heart and left ventricle (LV) were 0.44 Gy and 0.12 Gy respectively. There was no change in LV ejection fraction (pre proton-RT vs. 4-weeks post proton-RT vs. 2 months post proton-RT, 65±5 vs. 66±5 vs. 64±4%, p=0.15), global GLS (−21.7±2.7 vs. −22.7±2.3 vs. −22.8±2.1%, p=0.24) or segmental GLS from pre-to post proton-RT. Similarly, there was no change in hs-cTnI or NT-proBNP with proton-RT. However, post proton-RT, we found that patients with a history of hypertension had lower GLS when compared to women without hypertension (−21.3±3.5 vs. −24.0±2.4%, p=0.006).

Conclusion

Proton-RT did not impact LV function, or associate with an increase in biomarkers. These data support the potential cardiac benefits of proton-RT compared to conventional RT.

Funding Acknowledgement

Type of funding sources: None.

Effect of a multicomponent intervention on achievement and improvements in quality-of-care indices among people with Type 2 diabetes in South Asia: the CARRS trial

AIMS

To evaluate whether and what combinations of diabetes quality metrics were achieved in a multicentre trial in South Asia evaluating a multicomponent quality improvement intervention that included non-physician care coordinators to promote adherence and clinical decision-support software to enhance physician practices, in comparision with usual care.

METHODS

Using data from the Centre for Cardiometabolic Risk Reduction in South Asia (CARRS) trial, we evaluated the proportions of trial participants achieving specific and combinations of five diabetes care targets (HbA_1c <53 mmol/mol [7%], blood pressure <130/80 mmHg, LDL cholesterol <2.6 mmol/L, non-smoking status, and aspirin use). Additionally, we examined the proportions of participants achieving the following risk factor improvements from baseline: ≥11-mmol/mol (1%) reduction in HbA_1c , ≥10-mmHg reduction in systolic blood pressure, and/or ≥0.26-mmol/l reduction in LDL cholesterol.

RESULTS

Baseline characteristics were similar in the intervention and usual care arms. Overall, 12.3%, 29.4%, 36.5%, 19.5% and 2.2% of participants in the intervention group and 16.2%, 38.3%, 31.6%, 11.3% and 0.8% of participants in the usual care group achieved any one, two, three, four or five targets, respectively. We noted sizeable improvements in HbA_1c , blood pressure and cholesterol, and found that participants in the intervention group were twice as likely to achieve improvements in all three indices at 12 months that were sustained over 28 months of the study [relative risk 2.1 (95% CI 1.5,2.8) and 1.8 (95% CI 1.5,2.3), respectively].

CONCLUSIONS

The intervention was associated with significantly higher achievement of and greater improvements in composite diabetes quality care goals. However, among these higher-risk participants, very small proportions achieved the complete group of targets, which suggests that achievement of multiple quality-of-care goals is challenging and that other methods may be needed in closing care gaps.

System Xc- Antiporter Inhibitors: Azo-Linked Amino-Naphthyl-Sulfonate Analogues of Sulfasalazine

The cystine/glutamate antiporter system Xc- (SXc-) mediates the exchange of intracellular L-glutamate (L-Glu) with extracellular L-cystine (L-Cys2). Both the import of L-Cys2 and the export of L-Glu take on added significance in CNS cells, especially astrocytes. When the relative activity of SXc- overwhelms the regulatory capacity of the EAATs, the efflux of L-Glu through the antiporter can be significant enough to trigger excitotoxic pathology, as is thought to occur in glioblastoma. This has prompted considerable interest in the pharmacological specificity of SXc- and the development of inhibitors. The present study explores a series of analogues that are structurally related to sulfasalazine, a widely employed inhibitor of SXc-. We identify a number of novel aryl-substituted amino-naphthylsulfonate analogues that inhibit SXc- more potently than sulfasalazine. Interestingly, the inhibitors switch from a competitive to noncompetitive mechanism with increased length and lipophilic substitutions, a structure-activity relationship that was previously observed with aryl-substituted isoxazole. These results suggest that the two classes of inhibitors may interact with some of the same domains on the antiporter protein and that the substrate and inhibitor binding sites may be in close proximity to one another. Molecular modeling is used to explore this possibility.

Demonstration of a Longitudinal Medical Education Model (LMEM) Model to Teach Point-of-Care Ultrasound in Resource-Limited Settings

Background: Short-term medical missions prevail as the most common form of international medical volunteerism, but they are ill-suited for medical education and training local providers in resource-limited settings. Objective: The purpose of this study is to evaluate the effectiveness of a longitudinal educational program in training clinicians how to perform point-of-care ultrasound (POCUS) in resource-limited clinics. Design: A retrospective study of a four-month POCUS training program was conducted with clinicians from a rural hospital in Haiti. The model included one-on-one, in-person POCUS teaching sessions by volunteer instructors from the United States and Europe. The Haitian trainees were assessed at the start of the program and at its conclusion by a direct objective structured clinical examination (OSCE), administered by the visiting instructors, with similar pre- and post- program ultrasound competency assessments. Results: Post-intervention, a significant improvement in POCUS competency was observed across six different fundamental areas of ultrasound (p < 0.0001). According to our objective structured clinical examination (OSCE), the mean assessment score increased from 0.47 to 1.68 out of a maximum score of 2 points, and each trainee showed significant overall improvement in POCUS competency independent of the initial competency pre-training (p < 0.005). There was a statistically significant improvement in POCUS application for five of the six medically relevant assessment categories tested. Conclusion: Our results provide a proof-of-concept for the longitudinal education-centered healthcare delivery framework in a resource-limited setting. Our longitudinal model provides local healthcare providers the skills to detect and diagnose significant pathologies, thereby reducing avoidable morbidity and mortality at little or no addition cost or risk to the patient. Furthermore, training local physicians obviates the need for frequent volunteering trips, saving costs in healthcare training and delivery.

Long Peripheral Catheters: A Retrospective Review of Major Complications

The risk of infectious and noninfectious complications associated with long peripheral catheters (LPCs) is unknown. In this retrospective study of 539 catheters, we found LPCs were often placed for the indications of difficult access and long-term antibiotics. Rates of deep vein thrombosis (1.7%) and catheter-related infection (0.6%) were low. LPCs may represent a novel and safe option for short-term venous access.

Prognostic Value of Neutrophil-lymphocyte Ratio in Patients with Severe Alcoholic Hepatitis

Background

Prednisolone is considered the cornerstone treatment for severe alcoholic hepatitis (AH). However, its use is limited by the increased risk of infection in an already immunocompromised patient population. Among patients with severe AH, there exists a group of non-responders who do not benefit from prednisolone therapy. Day-4 Lille score is a widely employed prognostic model used to identify this non-responder subgroup. The present study evaluates the prognostic ability of the inflammatory marker, the neutrophil-lymphocyte ratio (NLR), as a stand-alone model and in conjunction with the day-4 Lille score.

Methods

We retrospectively reviewed the electronic medical records of patients diagnosed with AH. Demographic and biochemical data at diagnosis were collected to calculate Maddrey’s discriminant function (MDF) and model for end-stage liver disease (MELD) score upon admission and also on day 4. Receiver operating characteristic (ROC) curves were plotted for day-4 NLR and day-4 Lille score for prediction of 90-day mortality, and optimal cut-off values were determined. Patients were then subcategorized into groups based on the generated optimal cut-off values. Categorization was validated by comparing the mortality rate in each group with the chi-squared test. We then performed a multivariate analysis for prediction of 90-day mortality using day-4 Lille score and day-4 NLR, constructing a new prediction score based on the odds ratio (OR). The ROC curve of the new score was plotted and the area under a curve (AUC) was reported and compared with previously validated scores.

Results

Our analysis demonstrated that both day-4 NLR and Lille score individually predicted 90-day mortality with statistical significance (p: 0.049, p: <0.001, respectively). The ROC analysis of day-4 Lille score for the prediction of 90-day mortality revealed an AUC of 0.819 with an optimal cut-off value of 0.45 (sensitivity: 83.3%, specificity: 76.1%). Day-4 NLR had an AUC of 0.756 with an optimal cut-off value of 12.3 (sensitivity: 66.7%, specificity: 78.1%) The combined day-Lille-NLR model with a cut-off of 0.55 had an AUC of .889, which was higher than day-4 Lille score and NLR independently.

Conclusion

Day-4 NLR is an easily assessed prognostic model of mortality in alcoholic hepatitis. However, it often underperforms relative to day-4 Lille score. Combining these two models to create a "modified" Lille score adds increased performance characteristics to the prediction of outcomes/mortality. The "modified" Lille score presented in this study can be used to further cut down the number of non-responders who are often forced to undergo costly and potentially harmful treatment courses.

Tilapia Consumption and Scombroid Poisoning

Scombroid poisoning, also known as histamine fish poisoning, typically occurs after eating dark meat fish. Higher levels of histidine, which is converted to histamine, causes anaphylaxis-like symptoms upon ingestion. There are few reported cases of scombroid in humans secondary to light meat fish. We present a case secondary to tilapia consumption.

Ultrasound-guided Bedside Core Needle Biopsy: A Hospitalist Procedure Team's Experience

Tissue pathology is integral for the diagnosis of various conditions, especially malignancy. Traditionally, biopsy procedures, including core needle biopsy (CNB), are performed by surgeons or radiologists. With the increasing utilization of point of care ultrasound (POCUS) skills and competence in bedside procedures by general internists, CNB can be safely moved to the patient's bedside with maintained accuracy and increased cost savings compared to traditional procedural methods. We aim to review the experience of our hospitalist-run medical procedure service in performing these ultrasound-guided procedures at the bedside.

Bedside Peripherally Inserted Central Catheter Tip Confirmation: A Direct Savings Analysis

Peripherally inserted central catheter use has increased dramatically over the past decade, parallel to health care costs. Traditional bedside peripherally inserted central catheter placement requires anthropometric measurements of estimated catheter length and confirmation of appropriate tip positioning via chest radiograph. Newer bedside technology, using magnet and electrocardiogram capabilities, seeks to replace the traditional method with equal efficacy but less overall cost. The need for follow-up chest radiograph can been removed, a significant cost savings in direct patient care. In this retrospective case control study, we examine costs related to these 2 tip confirmation methods while assessing overall cost savings to the health care industry.

Abstract P2-11-04: Not presented

This abstract was not presented at the symposium.

Rifaximin versus norfloxacin for prevention of spontaneous bacterial peritonitis: a systematic review

Aim

The aim of this systematic review is to evaluate the efficacy and safety of rifaximin in the prophylaxis of spontaneous bacterial peritonitis (SBP) as compared with norfloxacin.

Methods

We searched MEDLINE, CINAHL, Google Scholar and Cochrane databases from inception to January 2017. Reference lists of articles as well as conference proceedings were manually screened. We included studies that recruited patients with cirrhosis and ascites who met the criteria for primary or secondary SBP prophylaxis as defined by the European Association for the Study of the Liver and American Association for the Study of Liver Diseases. Two independent investigators reviewed the studies for eligibility, extracted the data and assessed study quality using the Cochrane risk of bias tool. The primary outcome was occurrence of SBP. Secondary outcomes included mortality and adverse events with therapy.

Results

Of the 435 studies identified, a total of five were included for full-text review. Four studies were eligible for the systematic review, three of which were randomised controlled trials and one was a prospective observational study. The population examined in majority of studies was primarily hepatitis C cirrhosis. The results of individual studies indicated either superior efficacy of rifaximin or no statistical difference between rifaximin and norfloxacin for SBP prophylaxis.

Conclusions

Moderate-quality evidence shows that long-term use of rifaximin appears to be a reasonable alternative to norfloxacin for SBP prevention in hepatitis C cirrhosis.

Novel di-aryl-substituted isoxazoles act as noncompetitive inhibitors of the system Xc(-) cystine/glutamate exchanger

The system xc(-) antiporter is a plasma membrane transporter that mediates the exchange of extracellular l-cystine with intracellular l-glutamate. This exchange is significant within the context of the CNS because the import of l-cystine is required for the synthesis of the antioxidant glutathione, while the efflux of l-glutamate has the potential to contribute to either excitatory signaling or excitotoxic pathology. Changes in the activity of the transport system have been linked to the underlying pathological mechanisms of a variety of CNS disorders, one of the most prominent of which is its highly enriched expression in glial brain tumors. In an effort to produce more potent system xc(-) blockers, we have been using amino-3-carboxy-5-methylisoxazole propionic acid (ACPA) as a scaffold for inhibitor development. We previously demonstrated that the addition of lipophilic aryl groups to either the #4 or #5 position on the isoxazole ring markedly increased the inhibitory activity at system xc(-). In the present work a novel series of analogues has been prepared in which aryl groups have been introduced at both the #4 and #5 positions. In contrast to the competitive action of the mono-substituted analogues, kinetic analyses indicate that the di-substituted isoxazoles block system xc(-)-mediated uptake of (3)H-l-glutamate into SNB-19 cells by a noncompetitive mechanism. These new analogues appear to be the first noncompetitive inhibitors identified for this transport system, as well as being among the most potent blockers identified to date. These diaryl-isoxazoles should be of value in assessing the physiological roles and molecular pharmacology of system xc(-).

In vitro evaluation of Midwest Caries ID: a novel light-emitting diode for caries detection

INTRODUCTION

Traditional detection techniques have limits in diagnosing occlusal caries. Thus, more accurate methods are needed. This study evaluates the ability of the Midwest Caries ID (Midwest) to detect caries.

METHODS

Two hundred sixty-four extracted, nonrestored premolars and molars were cleaned and stored in 0.2% sodium azide. Teeth were divided into three groups of 88. One examination site on each occlusal surface was chosen. Each site was inspected by a calibrated examiner via visual, Midwest, and histologic exams. First, a visual exam was performed following the International Caries Detection and Assessment guidelines. Next, the same site was inspected using the Midwest device. Finally, the tooth was sectioned mesiodistally through the site. The half with greater caries progression was visualized under a stereomicroscope (64×). Histologic appearance was scored based on the Downer system. Data were analyzed using Kendall tau-b, partial correlation coefficients, and the receiver operating characteristics curve.

RESULTS

Overall, the Midwest scoring assessment correlated with histologic assessments (tau = 0.32; p<0.0001), but the visual exam had a stronger correlation (tau = 0.53; p<0.0001) with the histologic exam. The sensitivity and specificity of the Midwest was also reported at 0.56 and 0.84, compared with 0.92 and 0.43, respectively, for the visual exam.

CONCLUSIONS

Midwest Caries ID is a novel caries detection device that has limitations and should not be used as the sole means to detect occlusal caries.

Overexpression of the adiponectin receptor AdipoR1 in rat skeletal muscle amplifies local insulin sensitivity

Adiponectin is an adipokine whose plasma levels are inversely related to degrees of insulin resistance (IR) or obesity. It enhances glucose disposal and mitochondrial substrate oxidation in skeletal muscle and its actions are mediated through binding to receptors, especially adiponectin receptor 1 (AdipoR1). However, the in vivo significance of adiponectin sensitivity and the molecular mechanisms of muscle insulin sensitization by adiponectin have not been fully established. We used in vivo electrotransfer to overexpress AdipoR1 in single muscles of rats, some of which were fed for 6 wk with chow or high-fat diet (HFD) and then subjected to hyperinsulinemic-euglycemic clamp. After 1 wk, the effects on glucose disposal, signaling, and sphingolipid metabolism were investigated in test vs. contralateral control muscles. AdipoR1 overexpression (OE) increased glucose uptake and glycogen accumulation in the basal and insulin-treated rat muscle and also in the HFD-fed rats, locally ameliorating muscle IR. These effects were associated with increased phosphorylation of insulin receptor substrate-1, Akt, and glycogen synthase kinase-3β. AdipoR1 OE also caused increased phosphorylation of p70S6 kinase, AMP-activated protein kinase, and acetyl-coA carboxylase as well as increased protein levels of adaptor protein containing pleckstrin homology domain, phosphotyrosine binding domain, and leucine zipper motif-1 and adiponectin, peroxisome proliferator activated receptor-γ coactivator-1α, and uncoupling protein-3, indicative of increased mitochondrial biogenesis. Although neither HFD feeding nor AdipoR1 OE caused generalized changes in sphingolipids, AdipoR1 OE did reduce levels of sphingosine 1-phosphate, ceramide 18:1, ceramide 20:2, and dihydroceramide 20:0, plus mRNA levels of the ceramide synthetic enzymes serine palmitoyl transferase and sphingolipid Δ-4 desaturase, changes that are associated with increased insulin sensitivity. These data demonstrate that enhancement of local adiponectin sensitivity is sufficient to improve skeletal muscle IR.

Effect of silver diamine fluoride on microtensile bond strength to dentin

The aim of this in vitro study was to investigate the effect of the cariostatic and preventive agent silver diamine fluoride (SDF) on the microtensile bond strength of resin composite to dentin. Forty-two caries-free, extracted molars were flattened occlusally and apically using a diamond saw, and the exposed occlusal dentin was polished with a series of silicon carbide papers, all under water irrigation. The teeth were then randomly divided into six groups of seven teeth each that were treated as follows: 1) Peak SE self-etch bonding agent; 2) 12% SDF + Peak SE; 3) 38% SDF + Peak SE; 4) Peak LC etch-and-rinse bonding agent; 5) 12% SDF + Peak LC; and 6) 38% SDF + Peak LC. Four-millimeter buildups of Amelogen Plus were incrementally placed on all teeth; after a 24-hour storage period in distilled water, the specimens were sectioned perpendicular to the adhesive interface to produce beams of cross-sectional surface area measuring approximately 1 mm(2). The beams were placed on a microtensile testing machine, which utilized a single-speed pump motor and force gauge at 20 kgf × 0.01 second to record maximum tensile force before failure occurred. Two-way analysis of variance and post hoc Tukey tests were performed to compare the effects of the SDF on microtensile bond strength, with statistical significance set at α = 0.05. None of the experimental groups treated with different concentrations of SDF showed a significant difference in bond strength compared to the control groups, and there was no significant difference in bond strength between self-etch and etch-and-rinse groups. However, the effect of SDF on self-etch bonded teeth compared to etch-and-rinse bonded teeth was statistically significant (p=0.0363), specifically at the 12% concentration. SDF does not adversely affect the bond strength of resin composite to noncarious dentin.

Evaluation of the impact of HIV serostatus, tobacco smoking and CD4 counts on epidermoid anal cancer survival

Tobacco smoking and HIV infection increase the risk of epidermoid anal cancer (EAC). No published studies have examined smoking and EAC outcomes, and the literature is discrepant regarding outcomes of HIV-positive patients with EAC. The goal of this study was to examine smoking history, HIV status and outcomes in EAC patients. We conducted a retrospective analysis of adults with invasive EAC treated in the University of Washington hospital system from 1 January 1994 to 31 December 2008. Sixty-three patients were included. Forty-seven patients (75%) had primary chemoradiation, of whom 42 (89%) completed therapy. Two patients (3%) received radiotherapy alone. Fourteen patients (22%) underwent primary surgery, of whom 11 (79%) underwent tumour excision and three (21%) abdominoperineal resection (APR). We analysed smoking history, HIV status and CD4 count (≥200 cells/μL/<200 cells/μL for HIV-positive patients) versus outcomes. Forty-five patients (71%) were in remission, and 44 (70%) were alive at last follow-up. Overall survival was significantly better for never-smokers than for ever-smokers. There were no differences in outcomes according to HIV status or CD4 counts. Patients with anal cancer who smoke have worse overall survival than non-smoking patients. HIV infection does not appear to affect anal cancer outcomes.

Simultaneous spectrophotometric estimation of imipramine hydrochloride and chlordiazepoxide in tablets

A binary mixture of imipramine HCl and chlordiazepoxide was determined by three different spectrophotometric methods. The first method involved determination of imipramine HCl and chlordiazepoxide using the simultaneous equations and the second method involved absorbance ratio method. Imipramine has absorbance maxima at 251 nm, chlordiazepoxide has absorbance maxima at 264.5 nm and isoabsorptive point is at 220 nm in methanol. Linearity was obtained in the concentration ranges of 1-25 and 1-10 μg/ml for Imipramine HCL and Chlordiazepoxide, respectively. The third method involved determination of these two drugs using the first-derivative spectrophotometric technique at 219 and 231.5 nm over the concentration ranges of 1-20 and 2-24 μg/ml with mean accuracies 99.46±0.78 and 101.43±1.20%, respectively. These methods were successively applied to pharmaceutical formulations because no interferences from the tablet excipients were found. The suitability of these methods for the quantitative determination of the compounds was proved by validation.

The adaptor protein APPL1 increases glycogen accumulation in rat skeletal muscle through activation of the PI3-kinase signalling pathway

APPL1 is an adaptor protein that binds to both AKT and adiponectin receptors and is hypothesised to mediate the effects of adiponectin in activating downstream effectors such as AMP-activated protein kinase (AMPK). We aimed to establish whether APPL1 plays a physiological role in mediating glycogen accumulation and insulin sensitivity in muscle and the signalling pathways involved. In vivo electrotransfer of cDNA- and shRNA-expressing constructs was used to over-express or silence APPL1 for 1 week in single tibialis cranialis muscles of rats. Resulting changes in glucose and lipid metabolism and signalling pathway activation were investigated under basal conditions and in high-fat diet (HFD)- or chow-fed rats under hyperinsulinaemic-euglycaemic clamp conditions. APPL1 over-expression (OE) caused an increase in glycogen storage and insulin-stimulated glycogen synthesis in muscle, accompanied by a modest increase in glucose uptake. Glycogen synthesis during the clamp was reduced by HFD but normalised by APPL1 OE. These effects are likely explained by APPL1 OE-induced increase in basal and insulin-stimulated phosphorylation of IRS1, AKT, GSK3β and TBC1D4. On the contrary, APPL1 OE, such as HFD, reduced AMPK and acetyl-CoA carboxylase phosphorylation and PPARγ coactivator-1α and uncoupling protein 3 expression. Furthermore, APPL1 silencing caused complementary changes in glycogen storage and phosphorylation of AMPK and PI3-kinase pathway intermediates. Thus, APPL1 may provide a means for crosstalk between adiponectin and insulin signalling pathways, mediating the insulin-sensitising effects of adiponectin on muscle glucose disposal. These effects do not appear to require AMPK. Activation of signalling mediated via APPL1 may be beneficial in overcoming muscle insulin resistance.

Bronchoprovocation testing in asthma: effect on exhaled monoxides

Exhaled carbon monoxide and nitric oxide reflect allergic inflammation in asthma and have clinical utility for monitoring disease severity. The effects of allergen challenge and of inflammatory versus non-inflammatory bronchoconstrictive stimuli on the exhalation kinetics of these gases are unclear. The aim of this study is to compare and contrast the effects of methacholine and allergen challenges on the exhaled levels of carbon monoxide and nitric oxide in a cohort of adult subjects with atopic asthma. Eight subjects underwent inhaled allergen testing, nine underwent methacholine testing, and five subjects underwent both tests. Additionally, seven healthy controls underwent a mock challenge. Mixed-expired and end-expiratory carbon monoxide and end-expiratory nitric oxide levels were measured together with spirometry before, during (i.e. after each step of the inhalations), and after the challenges. Decreases in both end-expiratory (-14.4% in 9/11 subjects, p = 0.04) and mixed-expired (-7.5%, 9/11 subjects, p = 0.007) levels of carbon monoxide were noted during the immediate phase of the allergen challenge, with similar reductions after methacholine challenge, but levels were unaffected by repeated forced vital capacity exhalations alone. End-expiratory nitric oxide increased during the immediate phase of allergen challenge in 10/13 subjects (+10.8%, p = 0.05), but decreased after methacholine challenge in 14/14 subjects (-32.2%, p = 0.00009). Bronchospasm negatively modulates exhaled carbon monoxide and nitric oxide, but the inflammatory stimulus of allergen exposure increases exhaled nitric oxide. Measurements of exhaled monoxides may need to be referenced to the FEV(1).

Neurogenesis: role for microRNAs and mesenchymal stem cells in pathological states

Implantation of adult human mesenchymal stem cells (MSCs) to treat neural disorders shows promise. Depending on their microenvironment, MSCs could potentially be used for the repair and/or replacement of neurons in traumatic brain injury or the treatment of Parkinson's disease. This cross-disciplinary review incorporates aspects of neuroscience, stem cell biology, cancer biology and immunology to discuss interactions between inflammatory mediators and MSCs. We first discuss the role of microRNAs (miRNAs) in neurological development. Secondly, we discuss the ability of MSCs to transdifferentiate into functional neurons, which are regulated by miRNAs, and the implications of these cells for the therapy of neuropathological states. The administration of effective and safe MSC therapy must acknowledge immune mediators that may predispose the early differentiating MSCs to oncogenic insults. Thus, we discuss a key gene, RE-1 silencing transcription factor (REST), based on its dual role in neurogenesis and cancer development. Immune mediators could be central to MSC responses within a region of tissue injury and are also discussed in detail. Exploring the predisposition of MSCs to oncogenesis is critical for translational science since the implementation of safeguarding measures prior to therapy can lead to the successful delivery of stem cells to patients. The method by which MSCs could be applied for future therapies might require trans-disciplinary approaches for personalized treatments.

RP-HPLC Method for the Estimation of Dutasteride in Tablet Dosage Form

A simple, sensitive and precise RP-HPLC method was developed for the determination of dutasteride in tablet dosage form. The RP-HPLC separation was achieved on phenomenex C₁₈ column (250 mm, id 4.6 mm, 5 μm) using mobile phase methanol:water (90:10 v/v) at a flow rate of 1 ml/min at an ambient temperature. Quantification was achieved with photodiode array detection at 235 nm over the concentration range 1-12 μg/ml. The method was validated statistically and was applied successfully for the determination of dutasteride in tablets.

Activity monitoring and energy expenditure in COPD patients: a validation study

There is increasing interest in the objective measurement of physical activity in chronic obstructive pulmonary disease (COPD) patients due to the close relationship between physical activity level, health, disability and mortality. We aimed to (a) determine the validity and reproducibility of an activity monitor that integrates accelerometry with multiple physiologic sensors in the determination of energy expenditure in COPD subjects and (b) to document the independent contribution of the additional physiologic sensors to accelerometry measures in improving true energy expenditure determination. Eight subjects (4 male, FEV(1) 56.4 +/- 14.1%, RV 145.0 +/- 75.7%) performed 2 separate 6-minute walk and 2 incremental shuttle walk exercise tests. Energy expenditure was calculated during each exercise test using the physiologic activity monitor and compared to a validated exhaled breath metabolic system. Test-retest reproducibility of physiologic activity monitor during the walking tests was comparable to an exhaled breath metabolic system. Physiologic sensor data significantly improved the explained variance in energy expenditure determination (r(2)=0.88) compared to accelerometry data alone (r(2)=0.68). This physiologic activity monitor provides a valid and reproducible estimate of energy expenditure during slow to moderate paced walking in a laboratory setting and represents an objective method to assess activity in COPD subjects.

Survival after lung volume reduction in chronic obstructive pulmonary disease: insights from small airway pathology

RATIONALE

COPD is associated with reduced life expectancy.

OBJECTIVES

To determine the association between small airway pathology and long-term survival after lung volume reduction in chronic obstructive pulmonary disease (COPD) and the effect of corticosteroids on this pathology.

METHODS

Patients with severe (GOLD-3) and very severe (GOLD-4) COPD (n = 101) were studied after lung volume reduction surgery. Respiratory symptoms, quality of life, pulmonary function, exercise tolerance, chest radiology, and corticosteroid treatment status were assessed preoperatively. The severity of luminal occlusion, wall thickening, and the presence of small airways containing lymphoid follicles were determined in resected lung tissue. Kaplan-Meier survival analysis and Cox proportional hazards models were used to determine the relationship between survival and small airway pathology. The effect of corticosteroids on this pathology was assessed by comparing treated and untreated groups.

MEASUREMENTS AND MAIN RESULTS

The quartile of subjects with the greatest luminal occlusion, adjusted for covariates, died earlier than subjects who had the least occlusion (hazard ratio, 3.28; 95% confidence interval, 1.55-6.92; P = 0.002). There was a trend toward a reduction in the number of airways containing lymphoid follicles (P = 0.051) in those receiving corticosteroids, with a statistically significant difference between the control and oral +/- inhaled corticosteroid-treated groups (P = 0.019). However, corticosteroid treatment had no effect on airway wall thickening or luminal occlusion.

CONCLUSIONS

Occlusion of the small airways by inflammatory exudates containing mucus is associated with early death in patients with severe emphysema treated by lung volume reduction surgery. Corticosteroid treatment dampens the host immune response in these airways by reducing lymphoid follicles without changing wall thickening and luminal occlusion.

Expression of the vascular endothelial growth factor receptors 1 and 2 in acute myeloid leukemia: incidence and feasibility of immunohistochemical staining

Vascular endothelial growth factor (VEGF) and its receptor tyrosine kinases, VEGFR-1 and VEGFR-2, are important therapeutic targets for various cancers including AML. Paraffin-embedded bone marrow samples (PE-BM) are, in most cases, the only tissue accessible to perform retrospective analyses of novel targets such as VEGF and/or its receptors. As a result, it limits our options to immunohistochemistry (IHS), or more expensive and less practical techniques such as enzyme-linked immunosorbent assay (ELISA) or fluorescence in situ hybridization (FISH). We analyzed the feasibility of IHS to measure VEGFR-1 and VEGFR-2 expression in 28 AML samples using monoclonal antibodies (moAbs) against Flt-1 (VEGFR-1) and KDR/Flk-1 (VEGFR-2). Medical records were reviewed for relevant clinical information. Expression of VEGFR-1 (+) and VEGFR-2 (+) were seen in 25% (7/28) and 43% (12/28) respectively. Forty-six percent (13/28) were dual-negatives for VEGFR-1 and VEGFR-2; 14% (4/28) were dual-positives for VEGFR-1 and VEGFR-2. An inferior survival was observed in patients whose myeloblasts express either VEGFR-1 (+) or VEGFR-2 (+), or both. Determination of expression of VEGF receptors (1 and 2) by IHS in PE-BM tissue is feasible. Prospective comparison of IHC to flow cytometry or other molecular techniques, and assessment of the prognostic significance of VEGF receptors in AML patients is warranted.

Emerging concepts in outcome assessment for COPD clinical trials

The selection of appropriate, clinically meaningful outcome measures for chronic obstructive pulmonary disease (COPD) clinical trials is a complex issue. Functional exercise measures are more likely to adequately reflect the effect of novel and emerging interventions than traditional physiological measures such as forced expiratory volume in 1 second (FEV (1)). Nonetheless, among several exercise measures commonly used, the choice is not a simple issue and should be based upon rational as well as pragmatic issues. This is because important measurement properties (validity and responsiveness) can differ among exercise measures, among different interventions, and across degrees of disability. Furthermore, "free-living" daily activity measures may be more meaningful measures than these "in-lab" exercise measures for future clinical trials of COPD, although their reproducibility, validity, and responsiveness have not yet been adequately studied. Application of these and other emerging concepts in outcome assessment for COPD clinical trials will be examined.