Cardiovascular outcomes of Nephrotic syndrome in childhood (CVONS) study: a protocol for prospective cohort study

BACKGROUND

Nephrotic syndrome (NS) is characterized by dyslipidemia which is a well-known risk factor for atherogenesis. Atherosclerosis in childhood is mostly subclinical and endothelial dysfunction is known to precede this. Evidence for screening for endothelial dysfunction and cardiovascular risk factors and early identification of premature onset of atherosclerosis in childhood NS remains tenuous in the absence of well-designed prospective studies addressing cardiovascular comorbidity in NS. The objective of our study is to examine endothelial dysfunction and short-term cardiovascular outcomes in a carefully phenotyped cohort of patients with Nephrotic syndrome as compared to healthy controls.

METHODS

In a multi-centric prospective cohort study, 70 Steroid Resistant NS (SRNS), 70 Steroid Sensitive (SSNS) patients along with 70 Healthy Controls are being recruited. After a baseline assessment of functional and structural status of heart (2D Echocardiography), arteries (Carotid Doppler and Intima Media Thickness measurements) and microcirculation [a combination of 2D Echocardiography, Laser Doppler Flowmetry (LDF) and Brachial Artery Flow mediated dilation (FMD) and Nail Fold Capillaroscopy (NFC)], the patients are being investigated for endothelial dysfunction. Venous blood sample (15 ml) is being collected for routine investigations and assay of biochemical endothelial markers through Flow Cytometry. The patients will be followed up at 12 months and 24 months after the recruitment to look for any change from baseline period.

DISCUSSION

This study will able to provide a better understanding of the epidemiology of endothelial dysfunction and associated subclinical cardiovascular co-morbidity in childhood NS. Findings on characterization of prevalence of endothelial dysfunction and subclinical markers may be used to design future randomized controlled trials for evaluating the efficacy of preventive and therapeutic interventions in reducing the incidence of cardiovascular disease.

Abstract P3-09-05: Getting the most out of the 21-gene recurrence score assay: Increasing actionable results with a combined pathologic-genomic model

Introduction: The 21-gene recurrence score (RS) assay categorizes hormone receptor positive, node negative breast cancers (BC) into 3 risk groups for recurrence. We previously showed that the AAMC Model, using only standard pathology data, accurately does the same. This study compares the recurrence rate of the AAMC Model's risk groups to RS-based risk groups. A 2-step approach then is used, in which the AAMC model is applied first, and the RS assay is used only for AAMC intermediate risk cases. AAMC intermediate cases were reclassified by RS into low or high risk groups.

Methods: From a prospective registry of newly diagnosed BC, we selected invasive, hormone receptor positive, HER2 negative, lymph node negative cases from 2005 to 2015 tested with RS assay. Five-year Kaplan-Meier distant recurrence rates were calculated for each risk category.

Results: 1268 cases were included. Five-year recurrence rates were similar between the AAMC Model's low risk group and RS<18 low risk group, as well as between the AAMC Model's high risk group and the RS>30 high risk group. Applying the RS assay to the 715 cases in the AAMC Model's intermediate group resulted in re-classifying 417 (58%) as low risk and 41 (6%) as high risk. Using RS alone, 33% of cases were intermediate risk (n=424), whereas in the 2-step approach 20% were intermediate risk (n=257). For the 2-step approach, the 5-year distant recurrence rate was 3.3% for the low risk group (n=740) and 24.4% for the high risk group (n=271).

Conclusions: Five-year recurrence rates in the AAMC Model's low and high risk groups were similar to those in RS-based risk groups. The 2-step approach, with RS used only for AAMC intermediate cases, resulted in larger low and high risk groups with equivalent prognostic accuracy, compared to use of the RS assay alone. The 2-step approach reliably identifies a large number of patients unlikely to benefit from 21 gene assay and provides substantial cost savings.

Kaplan-Meier Calculated 5-year Distant Recurrences Rates for 4 Models: 1268 Patients Oncotype DXTAILORxAAMC Model2 Step Model with OncotypeDX for AAMC IntermediatesLow RiskRS < 18 (n=703)RS < 11 (n=250)Grade 1 and PR ≥ 1% (n=323)AAMC Low or AAMC intermediate/RS <18 (n=740) 3.4% (95% CI 1.6 – 5.1%, nf=17)4.0% (95% CI 0.8 – 7.2%, nf=8)2.7% (95% CI 0.0 – 5.4%, nf=5)3.3% (95% CI 1.4 – 5.2%, nf=16)Intermediate RiskRS 18 - 30 (n=424)RS 11 - 25 (n=787)Not meeting AAMC definition for low or high risk (n=715)AAMC Intermediate and RS 18-30 (n=257) 15.2% (95% CI 10.3 – 20.1%, nf=38)7.3% (95% CI 4.7 – 9.9%, nf=35)8.4% (95% CI 5.4 – 11.3%, nf=36)12.0% (95% CI 5.8 – 18.1%, nf=15)High RiskRS > 30 (n=141)RS > 25 (n=231)Grade 3 or ER < 20% (n=230)AAMC High or AAMC intermediate/RS > 30 (n=271) 23.0% (95% CI 14.7 – 31.3%, nf=27)22.9% (95% CI 15.9 – 29.9%, nf=39)22.8% (95% CI 16.1 – 29.5%, nf=41)24.4% (95% CI 18.0 – 30.7%, nf=51)RS= Recurrence Score, nf=number of recurrences, CI = confidence interval.

Citation Format: Mylander C, Rosman M, Gage M, Fujii T, Le Du F, Raghavendra A, Sinha A, Espinosa Fernandez JR, James A, Ueno N, Tafra L, Jackson R. Getting the most out of the 21-gene recurrence score assay: Increasing actionable results with a combined pathologic-genomic model [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-09-05.

Fluoride-associated ultrastructural changes and apoptosis in human renal tubule: a pilot study

The susceptibility of the kidneys to fluoride toxicity can largely be attributed to its anatomy and function. As the filtrate moves along the complex tubular structure of each nephron, it is concentrated in the proximal and distal tubules and collecting duct. It has been frequently observed that the children suffering from renal impairments also have some symptoms of dental and skeletal fluorosis. The findings suggest that fluoride somehow interferes with renal anatomy and physiology, which may lead to renal pathogenesis. The aim of this study was to evaluate the fluoride-associated nephrotoxicity. A total of 156 patients with childhood nephrotic syndrome were screened and it was observed that 32 of them had significantly high levels ( p ≤ 0.05) of fluoride in urine (4.01 ± 1.83 ppm) and serum (0.1 ± 0.013 ppm). On the basis of urinary fluoride concentration, patients were divided into two groups, namely group 1 (G-1) ( n = 32) containing normal urine fluoride (0.61 ± 0.17 ppm) and group 2 (G-2) ( n = 32) having high urine fluoride concentration (4.01 ± 1.83 ppm). Age-matched healthy subjects ( n = 33) having normal levels of urinary fluoride (0.56 ± 0.15 ppm) were included in the study as control (group 0 (G-0)). Kidney biopsies were taken from G-1 and G-2 only, who were subjected to ultrastructural (transmission electron microscopy) and apoptotic (terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling) analysis. Various subcellular ultrastructural changes including nuclear disintegration, chromosome condensation, cytoplasmic ground substance lysis, and endoplasmic reticulum blebbing were observed. Increased levels of apoptosis were observed in high fluoride group (G-2) compared to normal fluoride group (G-1). Various degrees of fluoride-associated damages to the architecture of tubular epithelia, such as cell swelling and lysis, cytoplasmic vacuolation, nuclear condensation, apoptosis, and necrosis, were observed.

Opioid-sparing effects of the thoracic interfascial plane blocks: A meta-analysis of randomized controlled trials

BACKGROUND

Thoracic interfascial plane blocks and modification (PECS) have recently gained popularity for analgesic potential during breast surgery. We evaluate/consolidate the evidence on opioid-sparing effect of PECS blocks in comparison with conventional intravenous analgesia (IVA) and paravertebral block (PVB).

MATERIALS AND METHODS

Prospective, randomized controlled trials comparing PECS block to conventional IVA or PVB in patients undergoing breast surgery published till June 2017 were searched in the medical database. Comparisons were made for 24-h postoperative morphine consumption and intraoperative fentanyl-equivalent consumption.

RESULTS

Final analysis included nine trials (PECS vs. IVA 4 trials and PECS vs. PVB 5 trials). PECS block showed a decreased intraoperative fentanyl consumption over IVA by 49.20 mcg (95% confidence interval [CI] =42.67-55.74) (I2 = 98.47%, P < 0.001) and PVB by 15.88 mcg (95% CI = 12.95-18.81) (I2 = 95.51%, P < 0.001). Postoperative, 24-h morphine consumption with PECS block was lower than IVA by 7.66 mg (95% CI being 6.23-9.10) (I2 = 63.15, P < 0.001) but was higher than PVB group by 1.26 mg (95% CI being 0.91-1.62) (I2 = 99.53%, P < 0.001). Two cases of pneumothorax were reported with PVB, and no complication was reported in any other group.

CONCLUSIONS

Use of PECS block and its modifications with general anesthesia for breast surgery has significant opioid-sparing effect intraoperatively and during the first 24 h after surgery. It also has higher intraoperative opioid-sparing effect when compared to PVB. During the 1st postoperative day, PVB has slightly more morphine sparing potential that may however be associated with higher complication rates. The present PECS block techniques show marked interstudy variations and need standardization.

The Indian monsoon variability and civilization changes in the Indian subcontinent

The vast Indo-Gangetic Plain in South Asia has been home to some of the world's oldest civilizations, whose fortunes ebbed and flowed with time-plausibly driven in part by shifts in the spatiotemporal patterns of the Indian summer monsoon rainfall. We use speleothem oxygen isotope records from North India to reconstruct the monsoon's variability on socially relevant time scales, allowing us to examine the history of civilization changes in the context of varying hydroclimatic conditions over the past 5700 years. Our data suggest that significant shifts in monsoon rainfall have occurred in concert with changes in the Northern Hemisphere temperatures and the discharges of the Himalayan rivers. The close temporal relationship between these large-scale hydroclimatic changes and the intervals marking the significant sociopolitical developments of the Indus Valley and Vedic civilizations suggests a plausible role of climate change in shaping the important chapters of the history of human civilization in the Indian subcontinent.

Haloperidol Versus 5-HT3 Receptor Antagonists for Postoperative Vomiting and QTc Prolongation: A Noninferiority Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials

Haloperidol is an antipsychotic with well-known antiemetic potential. It is underutilized for postoperative nausea vomiting due to reported corrected QT interval (QTc) prolongation. This meta-analysis evaluates its safety and efficacy as an antiemetic in the perioperative period. Trials comparing haloperidol to 5-HT₃ -receptor antagonists (5-HT₃ -RA) for 24 postoperative vomiting incidences published up to May 2017 were searched in the medical database. Comparisons were made for antiemetic efficiency variables (vomiting incidence, rescue antiemetic need, and patients with complete response) during early (until 6 hours) and late postoperative phases. Eight randomized controlled double-blinded trials were included in the final analysis. Twenty-four-hour vomiting incidence was similar in groups (fixed effects, P = 0.52, I² = 0%). Trial-sequential analysis confirmed noninferiority of haloperidol over 5-HT₃ -RAs (α = 5%, β = 20%, δ = 10%), with "information size" being 859 (required > 812). Pooled results did not demonstrate superiority/inferiority of 5-HT₃ -RAs over haloperidol in all other antiemetic efficacy variables (early and delayed). Negligible heterogeneity was found in all the comparisons made. Pooled Mantel Haenszel odds ratio for QTc prolongation was equivalent in both groups (fixed effects, P = 0.23, I² = 0%). The mean dose of haloperidol used was 1.34 mg, and no trial reported extrapyramidal side effects. Trial-sequential analysis showed statistical equivalence (α = 5%, β = 20%, δ = 10%), with information size being 745 (required > 591). Publication bias was unlikely (Egger test, X-intercept = 2.07, P = 0.10). We conclude that haloperidol is equivalent to the well-established 5-HT₃ -RAs in preventing vomiting during the first day after surgery. The incidence of QTc prolongation with haloperidol is statistically equivalent to 5-HT₃ -RAs and thus should not be the factor that discourages its use for treatment/prophylaxis of postoperative nausea vomiting.

Bilirubin concentration is positively associated with haemoglobin concentration and inversely associated with albumin to creatinine ratio among Indigenous Australians: eGFR Study

Low serum bilirubin concentrations are reported to be strongly associated with cardio-metabolic disease, but this relationship has not been reported among Indigenous Australian people who are known to be at high risk for diabetes and chronic kidney disease (CKD).

HYPOTHESIS

serum bilirubin will be negatively associated with markers of chronic disease, including CKD and anaemia among Indigenous Australians.

METHOD

A cross-sectional analysis of 594 adult Aboriginal and Torres Strait Islander (TSI) people in good health or with diabetes and markers of CKD. Measures included urine albumin: creatinine ratio (ACR), estimated glomerular filtration rate (eGFR), haemoglobin (Hb) and glycated haemoglobin (HbA1c). Diabetes was defined by medical history, medications or HbA1c≥6.5% or ≥48mmol/mol. Anaemia was defined as Hb<130g/L or <120g/L in males and females respectively. A multivariate regression analysis examining factors independently associated with log-bilirubin was performed.

RESULTS

Participants mean (SD) age was 45.1 (14.5) years, and included 62.5% females, 71.7% Aboriginal, 41.1% with diabetes, 16.7% with anaemia, 41% with ACR>3mg/mmol and 18.2% with eGFR<60mL/min/1.73m². Median bilirubin concentration was lower in females than males (6 v 8μmol/L, p<0.001) and in Aboriginal than TSI participants (6 v 9.5μmol/L, p<0.001). Six factors explained 35% of the variance of log-bilirubin; Hb and cholesterol (both positively related) and ACR, triglycerides, Aboriginal ethnicity and female gender (all inversely related).

CONCLUSION

Serum bilirubin concentrations were positively associated with Hb and total cholesterol, and inversely associated with ACR. Further research to determine reasons explaining lower bilirubin concentrations among Aboriginal compared with TSI participants are needed.

Exhaled breath profiles in the monitoring of loss of control and clinical recovery in asthma

BACKGROUND

Asthma is a chronic inflammatory airway disease, associated with episodes of exacerbations. Therapy with inhaled corticosteroids (ICS) targets airway inflammation, which aims to maintain and restore asthma control. Clinical features are only modestly associated with airways inflammation. Therefore, we hypothesized that exhaled volatile metabolites identify longitudinal changes between clinically stable episodes and loss of asthma control.

OBJECTIVES

To determine whether exhaled volatile organic compounds (VOCs) as measured by gas-chromatography/mass-spectrometry (GC/MS) and electronic nose (eNose) technology discriminate between clinically stable and unstable episodes of asthma.

METHODS

Twenty-three patients with (partly) controlled mild to moderate persistent asthma using ICS were included in this prospective steroid withdrawal study. Exhaled metabolites were measured at baseline, during loss of control and after recovery. Standardized sampling of exhaled air was performed, after which samples were analysed by GC/MS and eNose. Univariate analysis of covariance (ANCOVA), followed by multivariate principal component analysis (PCA) was used to reduce data dimensionality. Next paired t tests were utilized to analyse within-subject breath profile differences at the different time-points. Finally, associations between exhaled metabolites and sputum inflammation markers were examined.

RESULTS

Breath profiles by eNose showed 95% (21/22) correct classification for baseline vs loss of control and 86% (19/22) for loss of control vs recovery. Breath profiles using GC/MS showed accuracies of 68% (14/22) and 77% (17/22) for baseline vs loss of control and loss of control vs recovery, respectively. Significant associations between exhaled metabolites captured by GC/MS and sputum eosinophils were found (Pearson r≥.46, P<.01).

CONCLUSIONS & CLINICAL RELEVANCE

Loss of asthma control can be discriminated from clinically stable episodes by longitudinal monitoring of exhaled metabolites measured by GC/MS and particularly eNose. Part of the uncovered biomarkers was associated with sputum eosinophils. These findings provide proof of principle for monitoring and identification of loss of asthma control by breathomics.

Measured Glomerular Filtration Rate at Dialysis Initiation and Clinical Outcomes of Indian Peritoneal Dialysis Patients

The optimal time for dialysis initiation remains controversial. Studies have failed to show better outcomes with early initiation of hemodialysis; even a few had shown increased adverse outcomes including poorer survival. Few studies have examined the same in patients on peritoneal dialysis (PD). Measured glomerular filtration rate (mGFR) not creatinine-based estimated GFR is recommended as the measure of kidney function in end-stage renal disease (ESRD) patients. The objective of this observational study was to compare the outcomes of Indian patients initiated on PD with different residual renal function (RRF) as measured by 24-h urinary clearance method. A total of 352 incident patients starting on chronic ambulatory PD as the first modality of renal replacement therapy were followed prospectively. Patients were categorized into three groups as per mGFR at the initiation of PD (≤5, >5-10, and >10 ml/min/1.73 m2). Patient survival and technique survival were compared among the three groups. Patients with GFR of ≤5 ml/min/1.73 m2 (hazard ratio [HR] - 3.42, 95% confidence interval [CI] - 1.85-6.30, P = 0.000) and >5-10 ml/min/1.73 m2 (HR - 2.16, 95% CI - 1.26-3.71, P = 0.005) had higher risk of mortality as compared to those with GFR of >10 ml/min/1.73 m2. Each increment of 1 ml/min/1.73 m2 in baseline GFR was associated with 10% reduced risk of death (HR - 0.90, 95% CI - 0.85-0.96, P = 0.002). Technique survival was poor in those with an initial mGFR of ≤5 ml/min/1.73 m2 as compared to other categories. RRF at the initiation was also an important factor predicting nutritional status at 1 year of follow-up. To conclude, initiation of PD at a lower baseline mGFR is associated with poorer patient and technique survival in Indian ESRD patients.

Tuberculosis treatment outcomes among disadvantaged patients in India

Setting: Urban slums and poor rural areas in India, 2012-2014. Objective: To describe the characteristics of tuberculosis (TB) patients enrolled in treatment through Operation ASHA, a non-governmental organisation serving disadvantaged populations in India, and to identify risk factors for unfavourable treatment outcomes. Design: This was a retrospective cohort study. Patient characteristics were assessed for their relationship with treatment outcomes using mixed effects logistic regression, adjusting for clustering by treatment centre and Indian state. Outcomes were considered favourable (cured/treatment completed) or unfavourable (treatment failure, loss to follow-up, death, switch to multidrug-resistant TB treatment, transfer out). Results: Of 8415 patients, 7148 (84.9%) had a favourable outcome. On multivariable analysis, unfavourable outcomes were more common among men (OR 1.31, 95%CI 1.15-1.51), older patients (OR 1.12, 95%CI 1.04-1.21) and previously treated patients (OR 2.05, 95%CI 1.79-2.36). Compared to pulmonary smear-negative patients, those with extra-pulmonary disease were less likely to have unfavourable outcomes (OR 0.72, 95%CI 0.60-0.87), while smear-positive pulmonary patients were more likely to have unfavourable outcomes (OR 1.38, 95%CI 1.15-1.66 for low [scanty/1+] and OR 1.71, 95%CI 1.44-2.04 for high [2+/3+] positive smears). Conclusion: The treatment success rate within Operation ASHA is comparable to that reported nationally for India. Men, older patients, retreatment cases and smear-positive pulmonary TB patients may need additional interventions to ensure a favourable outcome.

Infection does not increase long-term mortality in patients with acute severe alcoholic hepatitis treated with corticosteroids

AIM

To determine whether infection in patients with acute severe alcoholic hepatitis (AAH) treated with corticosteroids is associated with increased mortality.

METHODS

Consecutive patients with AAH were treated with steroids and recruited to the study. Clinically relevant infections (body temperature > 38 °C or < 36 °C for more than 4 h, ascitic neutrophil count > 0.25 ×10⁹/L, consolidation on chest radiograph or clinically relevant positive microbiological culture of bodily fluid) were recorded prospectively. Clinical and laboratory parameters were recorded and survival at 90 d and 6 mo was determined. Univariate analysis of factors associated with 90-d mortality was performed and significant variables included in a multivariate analysis.

RESULTS

Seventy-two patients were included in the final analysis (mean age 47.9 years, 26% female, mean discriminant function 53.0). Overall mortality in the group occurred in 15 (21%), 23 (32%) and 31 (43%) at day 28, day 90 and 1 year respectively. 36 (50%) had a clinically relevant infection during their hospitalisation (23 after initiation of steroids). The median time to development of incident infection after commencement of steroids was 10 d. The commonest site of infection was ascites (31%) and bacteraemia (31%) followed by urinary tract (19%) and respiratory tract (8%). Forty-one separate organisms were isolated in 33 patients; the most frequent genus was Escherichia (22%) and Enterococcus (20%). Infection was not associated with 90-d or 1 year mortality but was associated with higher creatinine, model for end-stage liver disease and Lille score. Baseline urea was the only independent predictor of 90-d mortality.

CONCLUSION

Clinically relevant infections are common in patients with AAH but are not associated with increased 90-d or 1 year mortality.

Abstract PD7-03: A model using grade and hormone receptor staining defines groups at low vs. high risk for distant metastasis: Comparison to the 21-gene recurrence score

Background: The 21-gene recurrence score (RS) combines breast cancer (BC) expression of multiple genes into a single number which is prognostic for BC recurrence. We previously showed that a model using standard pathology data (AAMC Risk Groups) has substantial overlap with RS Risk Groups. The present study compared the recurrence rate of AAMC Risk Groups to that of RS-based Risk Groups as defined by the TAILORx trial and OncotypeDX (ODX) assay.

Methods: From a prospective registry of BC treated at MD Anderson Cancer Center (2/2005 – 5/2015), we selected cases tested with ODX. Cases were excluded for: other cancer in the past 5 years, T4 stage, node positivity, missing grade, missing ER%, ER&PR&lt;1% or HER2 positivity. Three methods were used to categorize distant metastatic risk: ODX and TAILORx Risk Groups were defined using RS, and AAMC Risk Groups were defined using grade and ER/PR level (Tables). For each method, the proportion of patients experiencing metastasis was calculated within Risk Groups.

Results: 1296 cases were included, with a mean follow-up of 3.5 years (25% had ≥ 4.9 years of follow-up). 82 cases (6.3%, 95% CI 5.1 – 7.8%) experienced distant metastasis, with a mean time-to-metastasis of 2.7 years. The proportion of patients experiencing distant metastasis was similar between the AAMC Low Risk Group (1.5%) and the TAILORx (3.2%) and ODX (2.4%) Low Risk Groups. The AAMC Low Risk Group was less than half the size of the ODX Low Risk Group. Of the 5 recurrences in the AAMC Low Risk Group, 1 was ODX Low Risk and 4 were ODX Intermediate Risk; 2 had 1% PR staining. Of the 17 recurrences in the ODX Low Risk Group, 1 was AAMC Low Risk and 5 (all grade 3) were AAMC High Risk; 3 had PR staining &lt; 10%. The proportion of patients experiencing distant metastasis was similar between the AAMC High Risk Group (17.4%) and the TAILORx (16.4%) and ODX (18.2%) High Risk Groups. The number of patients in the AAMC High Risk Group was greater than the ODX High Risk Group.

Table 1: Distant Metastasis in Low Risk GroupsAAMC Definition (n=329)TAILORx Definition (n=250)OncotypeDX Definition (n=704)Low Risk DefinitionGrade 1 & PR ≥1%RS &lt; 11RS &lt;18% with Distant Metastasis1.5% (95% CI 0.6–3.7%; n=5)3.2% (95% CI 1.5-6.4%, n=8)2.4% (95% CI 1.5-3.9%, n=17)% in Common with AAMC Low Risk Group100% (329/329)31.7% (80/250)33.3% (235/704)

Table 2: Distant Metastasis in High Risk GroupsAAMC Definition (n=235)TAILORx Definition (n=238)OncotypeDX Definition (n=148)High Risk DefinitionGrade 3 or ER &lt;20%RS &gt; 25RS &gt; 30% with Distant Metastasis17.4% (95% CI 12.9-23.0%, n=41)16.4% (95% CI 12.0-21.8%, n=39)18.2% (95% CI 12.6– 25.6%, n=27)% in Common with AAMC High Risk Group100% (235/235)56.7% (135/238)70.3% (104/148)

Conclusions: AAMC Low and High Risk Groups were prognostic of the likelihood of distant metastasis, and performed similarly to TAILORx and ODX Low and High Risk Groups. If RS were omitted for AAMC Low and High Risk cases, 44% [(329+235)/1296] of cases in the present cohort could have been spared ODX testing. The AAMC Risk Groups, using standard pathology data, can reliably identify a large number of patients unlikely to benefit from ODX testing and thus provide substantial cost savings.

Citation Format: Mylander C, Jackson RS, Rosman M, Fujii T, Le Du F, Raghavendra A, Sinha A, Ueno NT, Tafra L. A model using grade and hormone receptor staining defines groups at low vs. high risk for distant metastasis: Comparison to the 21-gene recurrence score [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD7-03.

Development of X-ray CCD camera based X-ray micro-CT system

Availability of microfocus X-ray sources and high resolution X-ray area detectors has made it possible for high resolution microtomography studies to be performed outside the purview of synchrotron. In this paper, we present the work towards the use of an external shutter on a high resolution microtomography system using X-ray CCD camera as a detector. During micro computed tomography experiments, the X-ray source is continuously ON and owing to the readout mechanism of the CCD detector electronics, the detector registers photons reaching it during the read-out period too. This introduces a shadow like pattern in the image known as smear whose direction is defined by the vertical shift register. To resolve this issue, the developed system has been incorporated with a synchronized shutter just in front of the X-ray source. This is positioned in the X-ray beam path during the image readout period and out of the beam path during the image acquisition period. This technique has resulted in improved data quality and hence the same is reflected in the reconstructed images.