Heat Stability of Two Candidate International Reference Preparations for Recombinant Human Tissue Factor

Adequate heat stability of international reference preparations (IRP) for thromboplastin (tissue factor) is an essential requirement. Accelerated degradation testing was performed by three laboratories on two candidate IRP for recombinant human tissue factor.

Heat treatment of these candidates resulted in slight shortening of the PT, contrasting with heat-induced prolongation of the PT observed with a conventional human brain derived IRP.

Heat stability of these candidates was improved when compared with the stability of previous recombinant human tissue factor preparations.

The PT-ratio did not change significantly when the candidates were stored for 28 days at 44° C. It’ can therefore be concluded that both candidates are acceptable with regard to stability.

Trusting the Record

Objectives: This paper aims to contribute to a longstanding interest in documents and paperwork in healthcare work through an examination of everyday work with patient records in a clinic.

Methods: An ethnographic study of record keeping practices in a deliberate self harm clinic was conducted to consider the role that document work plays in the development of trust in the routine social interactions of a working division of labor.

Results and conclusions: Issues of trust are seen to play central roles within the complexities of organizational working and some consequent implications for the deployment and use of electronic medical record systems are considered.

Improving ‘knife to skin time’: process modelling and new technology in medical work

As healthcare becomes information intensive technology increasingly plays an important role in managing patient care; information gathering and dissemination; and co-ordinating work. One approach to ensuring resources, staff and systems are allocated and used efficiently is process modelling. This paper presents some findings from the Dependability Interdisciplinary Research Collaboration (DIRC) project, on ‘process modelling’ as an aspect of managerial activity and the work involved in both creating and implementing process maps or models. Our ethnographic investigations document some of the problems in developing process maps of medical activity as part of a desire to ‘improve knife to skin time’. We suggest that process maps are not systematic, rational, scientific deductions of the most efficient process. Process maps are locally sensible versions of best practice, and problems may arise where such locally sensible versions are exported throughout an organization to other settings where other relevances may apply.

Lung stereotactic ablative radiotherapy (SABR): dosimetric considerations for chest wall toxicity

OBJECTIVE

To investigate chest wall pain in patients with peripheral early stage lung cancer treated with stereotactic ablative radiotherapy (SABR), and to identify factors predictive of Common Terminology Criteria of Adverse Events Grade 2 + chest wall pain.

METHODS

Patients who received 55 Gy in five fractions were included. A chest wall structure was retrospectively defined on planning scans, and chest wall dosimetry and tumour-related factors recorded. Logistic regression was performed to identify factors predictive of ≥Grade 2 chest wall pain.

RESULTS

182 patients and 187 tumours were included. There were 20 (10.9%) episodes of ≥Grade 2 chest wall pain. Multivariate logistic regression demonstrated that the maximum dose received by 1 cm(3) of chest wall (Dmax1 cm(3)) and tumour size were significant predictors of ≥Grade 2 chest wall pain [Dmax1 cm(3) odds ratio : 1.104, 95% confidence interval : 1.012-1.204, p = 0.025; tumour size (mm) odds ratio : 1.080, 95% confidence interval : 1.026-1.136, p = 0.003]. This model was an adequate fit to the data (Hosmer and Lemeshow test non-significant) and a fair discriminator for chest wall pain (area under receiver-operating characteristic curve: 0.74). Using the multivariate logistic regression model, parameters for Dmax1 cm(3) are provided, which predict <10% and <20% risks of ≥Grade 2 chest wall pain for different tumour sizes.

CONCLUSION

Grade 2+ chest wall pain is an uncommon side effect of lung SABR. Larger tumour size and increasing Dmax1 cm(3) are significant predictors of ≥Grade 2 chest wall pain. When planning lung SABR, it is prudent to try to avoid hot volumes in the chest wall, particularly for larger tumours.

ADVANCES IN KNOWLEDGE

This article demonstrates that Grade 2 or greater chest wall pain following lung SABR is more common when the tumour is larger in size and the Dmax1 cm(3) of the chest wall is higher. When planning lung SABR, the risk of chest wall pain may be reduced if maximum doses are minimized, particularly for larger tumours.

Audit and review for evidence-based red cell wastage reduction measures

Stocks of red blood cells (RBC) are held to ideally match supply and demand; hold too great a stock and unnecessary wastage occurs; too low a stock results in delay or lack of blood for the patient. Blood is a precious resource and its supply needs to be managed effectively. The aim was to identify how RBC units are wasted and propose laboratory-based reduction measures that would not compromise the clinical requirements of the patient. Wastage of RBC was investigated using a 'dashboard' query of a laboratory information management system. By employing service improvement tools, proposals were made to reduce unnecessary RBC waste while ensuring an adequate supply to the patient. The efficacy of those proposals was examined using the same dashboard to compare similar periods before and after their introduction. The reduction in RBC wastage for all groups during an eight month period (December to July) was from 6.4% (5.3% non-AB or B RhD-positive) pre-implementation to 4.4% (2.5% non-AB/B RhD-positive) post-implementation. Group O RhD-negative wastage reduced from 10.4% to 4.4% after introduction of waste-saving proposals. However, there was an increase in staff time required to introduce the changes and in associated Group and Screen testing (3.4 to 3.8 per unit issued). RBC wastage was significantly reduced (P<0.0001) by 32.8% (52%, non-AB/B RhD-positive), saving approximately 225 RBC units per annum. Financially, increased associated costs did not negate the savings made by the measures introduced.

Abstract P6-04-10: Clinicopathological and molecular characteristics of pleomorphic invasive lobular carcinoma of breast

Background: Pleomorphic invasive lobular carcinoma (PILC) is described as a distinct morphological variant of invasive lobular carcinoma (ILC) but its clinical behavior is not well characterized. PILCs have loss of E-cadherin similar to ILCs but have distinct morphological features like nuclear contour irregularity, a single prominent nucleolus, increased hyperchromasia and more frequent mitoses. In addition, some studies have reported that PILCs have acquired further molecular alterations such as gain of HER2/neu, amplification of c-myc and loss of p53. To the best of our knowledge there have been no studies evaluating Phosphoinositide 3 kinase/Akt/mammalian (or mechanistic) target of rapamycin (PI3K/Akt/mTOR) pathway in PILC. We hypothesize that there is increased activation of PI3K/Akt/mTOR pathway in PILC compared to ILC. Activation of the PI3k/Akt/mTOR pathway was evaluated by quantifying protein expression of phosphatase and tensin homolog (PTEN) and phosphorylated-S6 kinase1 (p-S6K1). PTEN is a negative regulator of the PI3K pathway and its loss/decreased expression (by mutation or allelic imbalance) activates downstream signaling. Loss (or decrease) of PTEN expression has been reported to be associated with PI3K pathway activation in more than 50% of ER+ breast tumors. Since PI3K pathway can be activated by other mechanisms in addition to PTEN loss, we hypothesized that evaluation of pS6K1 may predict activation of this pathway more than PTEN protein expression alone.

Methods: We conducted a retrospective translational study at the University of Arizona Cancer Center. Our Pathology database was searched to identify PILCs from 2012-2014. Two investigators reviewed the pathology reports independently and abstracted clinocopathological data. Formalin-fixed paraffin embedded (FFPE) primary PILCs were stained for PTEN and pS6K1 expression. Expression of PTEN and pS6K1 was quantified by long score methodology as low (≤ 10), moderate (11-50) or high (≥ 50) expression.

Results: We identified 19 patients with PILC. All tumors were either moderately (n=10) or poorly differentiated (n=9). Estrogen receptor (ER) was positive in all, progesterone receptor (PR) was positive in 11(52%) and HER2 was negative in all tumors. Proliferation index (Ki67) was elevated in all tumors (median 32%, range 20-70%). Lymph nodes were involved with metastatic carcinoma in 7 patients (negative in 9 and unknown in 3). The 21-gene recurrence score assay (Oncotype Dx) was performed in 10 patients and demonstrated higher scores (median 23, range 6-36) with the majority being in the intermediate or high range (8/10). Expression of PTEN and p-S6K1 was quantified on 10 FFPE tumor tissues. PTEN expression was high in all while pS6K1 was high in 8 and low in 2 tumors.

Conclusion: PILCs are a biologically distinct group of ILC. Clinicopathological characteristics suggest they would have a more clinically aggressive behavior (higher grade, high proliferative index and 21 gene recurrence score). In addition, our results indicate that PI3k/Akt/mTOR pathway in activated in majority of these tumors and that PTEN is not the key regulator of this pathway. Genomic profiling is currently underway to further analyze other causes of pathway activation.

Citation Format: Segar J, Baker AF, MacKerricher W, Nagle R, Livingston R, Clarke K, Ley M, Viscusi R, Gonzalez V, LeBeau L, Chalasani P. Clinicopathological and molecular characteristics of pleomorphic invasive lobular carcinoma of breast. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-04-10.

Predicting Radiation Esophagitis Using 18F-FDG PET During Chemoradiotherapy for Locally Advanced Non-Small Cell Lung Cancer

INTRODUCTION

Treatment of locally advanced non-small cell lung cancer with chemoradiotherapy (CRT) is limited by development of toxicity in normal tissue, including radiation esophagitis (RE). Increasingly, (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is being used for adaptive planning. Our aim was to assess changes in esophageal FDG uptake during CRT and relate the changes to the onset and severity of RE.

METHODS

This prospective study in patients with stage II-III non-small cell lung cancer involved serial four-dimensional computed tomography and PET scans during CRT (60-74Gy). RE was recorded weekly using the Common Terminology Criteria for Adverse Events (v4.0), and imaging was performed at weeks 0, 2, 4, and 7. Changes in the esophagus's peak standard uptake value (SUVpeak) were analyzed for each time point and correlated with grade of RE using the Wilcoxon rank-sum test. The volume of esophagus receiving 50 Gy (V50) and volume of esophagus receiving 60 Gy (V60) were correlated with the development of RE, and the C-statistic (area under the curve [AUC]) was calculated to measure predictivity of grade 3 RE.

RESULTS

RE developed in 20 of 27 patients (74%), with grade 3 reached in 6 (22%). A significant percentage increase in SUVpeak in the patients with RE was noted at week 4 (p = 0.01) and week 7 (p = 0.03). For grade 3 RE, a significant percentage increase in SUVpeak was noted at week 2 (p = 0.01) and week 7 (p = 0.03) compared with that for less than grade 3 RE. Median V50 (46.3%) and V60 (33.4%) were significantly higher in patients with RE (p = 0.04). The AUC measurements suggested that the percentage change in SUVpeak at week 2 (AUC = 0.69) and V50 (AUC = 0.67) and V60 (AUC = 0.66) were similarly predictive of grade 3 RE.

CONCLUSIONS

Serial FDG-PET images during CRT show significant increases in SUVpeak for patients in whom RE develops. The changes at week 2 may predict those at risk for the development of grade 3 RE and may be informative for adaptive planning and early intervention.

Eukaryotic translation initiation factor 6 is a novel regulator of reactive oxygen species-dependent megakaryocyte maturation

BACKGROUND

Ribosomopathies constitute a class of inherited disorders characterized by defects in ribosome biogenesis and function. Classically, bone marrow (BM) failure is a clinical symptom shared between these syndromes, including Shwachman-Bodian-Diamond syndrome (SBDS). Eukaryotic translation initiation factor 6 (eIF6) is a critical translation factor that rescues the quasilethal effect of the loss of the SBDS protein.

OBJECTIVES

To determine whether eIF6 activity is necessary for BM development.

METHODS

We used eIF6(+/-) mice and primary BM megakaryocytes to investigate the involvement of eIF6 in the regulation of hematopoiesis.

RESULTS

We provide evidence that reduced eIF6 expression negatively impacts on megakaryopoiesis. We show that inhibition of eIF6 leads to a reduction in cell size and mean ploidy level of megakaryocytes and a delay in megakaryocyte maturation by blocking the G1 /S transition. Consistent with this phenotype, only few megakaryocyte-forming proplatelets were found in eIF6(+/-) cells. We also discovered that, in eIF6(+/-) cells, the steady-state abundance of mitochondrial respiratory chain complex I-encoding mRNAs is decreased, resulting in decreased reactive oxygen species (ROS) production. Intriguingly, connectivity map analysis showed that eIF6-mediated changes overlap with specific translational inhibitors. eIF6 is a translation factor acting downstream of insulin/phorbol 12-myristate 13-acetate (PMA) stimulation. PMA treatment significantly restored eIF6(+/-) megakaryocyte maturation, indicating that activation of eIF6 is essential for the rescue of the phenotype.

CONCLUSIONS

Taken together, our results show a role for eIF6-driven translation in megakaryocyte development, and unveil the novel connection between translational control and ROS production in this cell subset.

Stereotactic Ablative Radiotherapy (SABR) in Patients with Medically Inoperable Peripheral Early Stage Lung Cancer: Outcomes for the First UK SABR Cohort

AIMS

To report outcomes for the first UK cohort treated for early stage peripheral lung cancer using stereotactic ablative radiotherapy (SABR).

MATERIALS AND METHODS

Patients were included who received SABR between May 2009 and May 2012. Electronic medical records were reviewed for baseline characteristics, treatment details and outcomes. Patients were treated according to the UK SABR Consortium Guidelines. Univariate and multivariate Cox regression was used to determine factors that influenced overall survival and local control.

RESULTS

In total, 273 patients received SABR for 288 lesions in the time period examined. The median follow-up was 19.7 months. The median overall survival for all patients was 27.3 months, with 1, 2 and 3 year overall survival of 78.0, 54.9 and 38.6%, respectively. The 1, 2 and 3 year rates of local control were 98.2, 95.7 and 95.7%, respectively. All patients completed the planned course of treatment and rates of Common Toxicity Criteria grade 3+ toxicity were low. On multivariate analysis, patients with Medical Research Council (MRC) breathlessness scores of 3-5 had worse overall survival compared with patients with scores of 1-2 (hazard ratio: 2.10; 95% confidence interval: 1.25-3.59) and the presence of histological diagnosis conferred improved overall survival (hazard ratio: 0.54; 95% confidence interval: 0.31-0.93), probably reflecting that patients who are considered well enough to undergo biopsy are generally fitter overall. No factors were identified that significantly influenced local control.

CONCLUSIONS

SABR is an effective and well-tolerated treatment option for patients with early stage peripheral lung cancer who are not suitable for surgery. No patient cohort was identified in whom SABR was considered inappropriate. This series adds to the existing positive data that support SABR for this patient group.

Details of left ventricular radial wall motion supporting the ventricular theory of the third heart sound obtained by cardiac MR

OBJECTIVE

Obtaining new details of radial motion of left ventricular (LV) segments using velocity-encoding cardiac MRI.

METHODS

Cardiac MR examinations were performed on 14 healthy volunteers aged between 19 and 26 years. Cine images for navigator-gated phase contrast velocity mapping were acquired using a black blood segmented κ-space spoiled gradient echo sequence with a temporal resolution of 13.8 ms. Peak systolic and diastolic radial velocities as well as radial velocity curves were obtained for 16 ventricular segments.

RESULTS

Significant differences among peak radial velocities of basal and mid-ventricular segments have been recorded. Particular patterns of segmental radial velocity curves were also noted. An additional wave of outward radial movement during the phase of rapid ventricular filling, corresponding to the expected timing of the third heart sound, appeared of particular interest.

CONCLUSION

The technique has allowed visualization of new details of LV radial wall motion. In particular, higher peak systolic radial velocities of anterior and inferior segments are suggestive of a relatively higher dynamics of anteroposterior vs lateral radial motion in systole. Specific patterns of radial motion of other LV segments may provide additional insights into LV mechanics.

ADVANCES IN KNOWLEDGE

The outward radial movement of LV segments impacted by the blood flow during rapid ventricular filling provides a potential substrate for the third heart sound. A biphasic radial expansion of the basal anteroseptal segment in early diastole is likely to be related to the simultaneous longitudinal LV displacement by the stretched great vessels following repolarization and their close apposition to this segment.

Effects of ventricular insertion sites on rotational motion of left ventricular segments studied by cardiac MR

OBJECTIVE

Obtaining new details for rotational motion of left ventricular (LV) segments using velocity encoding cardiac MR and correlating the regional motion patterns to LV insertion sites.

METHODS

Cardiac MR examinations were performed on 14 healthy volunteers aged between 19 and 26 years. Peak rotational velocities and circumferential velocity curves were obtained for 16 ventricular segments.

RESULTS

Reduced peak clockwise velocities of anteroseptal segments (i.e. Segments 2 and 8) and peak counterclockwise velocities of inferoseptal segments (i.e. Segments 3 and 9) were the most prominent findings. The observations can be attributed to the LV insertion sites into the right ventricle, limiting the clockwise rotation of anteroseptal LV segments and the counterclockwise rotation of inferoseptal segments as viewed from the apex. Relatively lower clockwise velocities of Segment 5 and counterclockwise velocities of Segment 6 were also noted, suggesting a cardiac fixation point between these two segments, which is in close proximity to the lateral LV wall.

CONCLUSION

Apart from showing different rotational patterns of LV base, mid ventricle and apex, the study showed significant differences in the rotational velocities of individual LV segments. Correlating regional wall motion with known orientation of myocardial aggregates has also provided new insights into the mechanisms of LV rotational motions during a cardiac cycle.

ADVANCES IN KNOWLEDGE

LV insertion into the right ventricle limits the clockwise rotation of anteroseptal LV segments and the counterclockwise rotation of inferoseptal segments adjacent to the ventricular insertion sites. The pattern should be differentiated from wall motion abnormalities in cardiac pathology.