The Implications of Laterality in Unilateral Cleft Lip Reconstruction: A Global Survey of Cleft Surgeons

OBJECTIVE

To explore the impact of directional laterality in complete Unilateral Cleft Lip (UCL) amongst the global cleft surgeon community.

DESIGN

Cross-sectional survey study.

SETTING

Global distribution of online survey distributed in English and Spanish.

PARTICIPANTS

Cleft surgeons from around the world.

MAIN OUTCOME MEASURES

Survey participant perception of the impact of laterality on: (1) cleft presentation (2) surgical challenge and (3) surgical outcomes.

RESULTS

Responses were received from 453 cleft surgeons located in 54 countries around the world. 221 (49%) had previously considered differences in patients presenting with a left- versus right-sided UCL. 95 (21%) considered right-sided clefts more difficult to reconstruct, 37 (8%) reported left-sided clefts to be more difficult and 321 (71%) reported no difference in difficulty between the cleft sides. Higher volume cleft surgeons, characterised by those reporting cleft as their principal area of practice and performing >20 cleft operations per year, were more likely to have both previously considered differences in laterality in cleft and to report right-sided unilateral cleft lip to be more difficult to primarily reconstruct. 395 (87%) did not consider surgical outcomes to be influenced by cleft laterality.

CONCLUSIONS

This survey reports perceptions on cleft laterality from a large body of global surgeons and suggests a trend for increased difficulty in right-sided compared to left-sided cleft lip reconstruction, where such laterality-associated difficulty is perceived.

A 2-4 keV multilayer mirrored channel for the NIF Dante system

During inertial confinement fusion experiments at the National Ignition Facility (NIF), a capsule filled with deuterium and tritium (DT) gas, surrounded by a DT ice layer and a high-density carbon ablator, is driven to the temperature and densities required to initiate fusion. In the indirect method, 2 MJ of NIF laser light heats the inside of a gold hohlraum to a radiation temperature of 300 eV; thermal x rays from the hohlraum interior couple to the capsule and create a central hotspot at tens of millions degrees Kelvin and a density of 100-200 g/cm³. During the laser interaction with the gold wall, m-band x rays are produced at ∼2.5 keV; these can penetrate into the capsule and preheat the ablator and DT fuel. Preheat can impact instability growth rates in the ablation front and at the fuel-ablator interface. Monitoring the hohlraum x-ray spectrum throughout the implosion is, therefore, critical; for this purpose, a Multilayer Mirror (MLM) with flat response in the 2-4 keV range has been installed in the NIF 37° Dante calorimeter. Precision engineering and x-ray calibration of components mean the channel will report 2-4 keV spectral power with an uncertainty of ±8.7%.

Hot Spot Evolution Measured by High-Resolution X-Ray Spectroscopy at the National Ignition Facility

Evolution of the hot spot plasma conditions was measured using high-resolution x-ray spectroscopy at the National Ignition Facility. The capsules were filled with DD gas with trace levels of Kr and had either a high-density-carbon (HDC) ablator or a tungsten (W)-doped HDC ablator. Time-resolved measurement of the Kr Heβ spectra, absolutely calibrated by a simultaneous time-integrated measurement, allows inference of the electron density and temperature through observing Stark broadening and the relative intensities of dielectronic satellites. By matching the calculated hot spot emission using a collisional-radiative code to experimental observations, the hot spot size and areal density are determined. These advanced spectroscopy techniques further reveal the effect of W dopant in the ablator on the hot spot parameters for their improved implosion performance.

Outcomes of microsurgical free tissue transfer performed on international surgical collaborations in low-income and middle-income countries: A systematic review and meta-analysis

BACKGROUND

Microsurgical free tissue transfer is the gold standard for reconstruction of significant soft tissue and bony defects following cancer resection and trauma. Many reconstructive units in low-income and middle-income countries (LMICs) do not yet have access to the resources or training required to perform microsurgical procedures. Long-term international collaborations have been formed with annual reconstructive programmes conducting microsurgery.

AIMS

To critically analyze outcomes of microsurgical free tissue transfer performed on international reconstructive collaborations in LMICs.

METHODS

PRISMA-compliant systematic review and meta-analysis of outcomes for free tissue transfer performed during international collaborations in LMICs using an inverse variance model. The study protocol was published prospectively and registered with PROSPERO (ID: CRD42021225613).

RESULTS

Seven studies, included 290 flaps on 284 patients. The most common sites requiring reconstruction were Head and neck (53% (n = 153)) and lower limb (7.9% (n = 23)) were lower limb reconstruction. The most common free flaps were radial forearm (22%; n = 64) and anterolateral thigh (18%; n = 51). Total Flap Failure rate was 3.8% (n = 13; 95% confidence interval (CI) = 1.9-6.3%) Overall complication rate was 38% (95% CI =27-48%), with 19% of flaps requiring emergency return to theatre (95% CI =14-26%). Flap salvage was successful in 52% of take-backs (95% CI =15% - 88%).

CONCLUSIONS

Free flaps performed during international surgical collaborations in LMICs have comparable failure rates to those performed in higher-income settings. However, there are higher complication and take-back rates. This should be taken into account when planning international collaborations. These results should help preoperative counselling and the consent process.

59 Burns in Low- and Middle-income Countries: A Scientometric Analysis of Peer-reviewed Research

Introduction

Low- and middle-income countries (LMICs) account for 70% of all global burns. Due to this significantly disproportionate burden, it’s critical we identify barriers to burn care and prevention in LMICs. As a result, this study aimed to elucidate trends in LMIC-related burn research to create focused strategies for burn care training, research, and innovation. Accomplishing meaningful change from the study’s findings will be guided by the first 4 steps of Dr. John Kotter’s “8-Step Process for Leading Change” – 1) create urgency for change, 2) build a guiding team, 3) develop a vision and plan, 4) communicate with key stakeholders to obtain buy-in.

Methods

Web of Science’s 7 citation databases were searched through March 2, 2021 using synonyms of “burns” and “low- and middle-income countries.” After screening articles, metadata were uploaded to VOSviewer (Leiden, Netherlands) where citation and network metrics were generated. The Kruskal-Wallis test and linear regression were used for bivariable and multivariable analysis of factors influencing publications, citations, and total link strength (TLS) – the strength of association between a given research article, other articles, and additional institutions.

Results

Bibliometric analysis identified 2,027 articles by 8,602 authors in 692 journals. Two-thirds of journals published a single article (n=453, 65.5%) whereas only 3.6% published ≥10 articles. One-quarter of LMIC burn research was published in ISBI’s Burns (n=417 articles, 20.6%) and ABA’s Journal of Burn Care & Research (n=89 articles, 4.4%). Most authors published < 5 articles (n=8521, 99.1%) but 19 (0.2%) had published ≥10. Authors were affiliated with 2,519 organizations in 132 countries. There was a strong positive correlation between total publications and citations (R=0.87, P< 0.001). In addition, there was a significant difference in the number of publications (P=0.003, 0.07), citations (P=0.005, 0.03), and TLS (P=0.009, 0.008) by geographic and economic categories - North America had the highest while Latin American and the Caribbean had the lowest. The USA (n = 563), India (n = 161), and China (n = 154) published the most articles.

Conclusions

Given the disproportionate representation of high-income countries and authors in the current LMIC burn research landscape, there must be a sense of urgency to develop pathways for facilitating change. Local and regional candidates for mentors and leaders were identified using bibliometric findings. Assembling teams with these individuals and prolific authors using a well-defined vision for change will facilitate sustainable communication and collaboration within LMIC research.

231 ESTABLISHING AN INTERVENTIONS BUNDLE TO IMPROVE INPATIENT CARE FOR PATIENTS WITH PARKINSON’S DISEASE: A MULTIDISCIPLINARY QUALITY IMPROVEMENT PROJECT

Background

Patients with Parkinson’s (PwP) are at a higher risk of complications once admited to hospital compared to their age-matched peers. Medication mismanagement is a well-known obstacle, which puts PwP at risk of sub-optimal treatment leading to an unnecessary deterioration of baseline and potentially increases risk of adverse sequelae.

Methods

Retrospective electronic patient records (EPR)/chart review of 47 admissions was conducted, across three hospital sites.

Data attaining to correct prescribing of medication on admission and discharge, prescribing of contraindicated medications, reasons for medication lapses and complications of inpatient stay were collected. EPR of 17 patients’ were reviewed to assess if Parkinson’s disease (PD) medication administrations occurred within 30 minutes of patient schedule, as recommended by NICE guidelines. Key areas for improvement were identified based on the results.

Results

47 charts (30 Males, 17 Females) with mean age 72 (range:57–90), were reviewed. Average number of co-morbidities:4.5 and Clinical Frailty Scale ranged 5–9 (n = 30). LOS averaged 12.4 days and 43% of patients had ≥2 hospital admissions in the preceeding year.

38% (17/44) of admissions correctly documented patient specific medication times. Only 48% of patients (n = 638) received their medications within 30 minutes of the scheduled time. 47% (22/47) experienced complications attributable to PD. Contraindicated medications were noted in 5 cases. 84% of discharging prescriptions did not mention timing of PD medication and 3 prescriptions had errors with regards to dosage/omission of medication.

Conclusion

We implemented across two sites: 1) Care protocol flag in patient’s chart highlighting simple avoidable complications. 2) Laminated over the bed signpost alerting ‘time critical medication’. 3) ‘Time critical medication’ stickers in drug kardex 4) Education sessions for Medical, Nursing and Ward staff. 6) Establishing out of hours access to PD medications and protocols for NPO/poor swallow. We plan to reassess significance of efforts post intervention.

Protocol for a systematic review of outcomes from microsurgical free-tissue transfer performed on short-term collaborative surgical trips in low-income and middle-income countries

BACKGROUND

In many units around the world, microsurgical free-tissue transfer represents the gold standard for reconstruction of significant soft tissue defects following cancer, trauma or infection. However, many reconstructive units in low-income and middle-income countries (LMICs) do not yet have access to the resources, infrastructure or training required to perform any microsurgical procedures. Long-term international collaborations have been formed with annual short-term reconstructive missions conducting microsurgery. In the first instance, these provide reconstructive surgery to those who need it. In the longer-term, they offer an opportunity for teaching and the development of sustainable local services.

METHODS

A PRISMA-compliant systematic review and meta-analysis will be performed. A comprehensive, predetermined search strategy will be applied to the MEDLINE and Embase electronic databases from inception to August 2021. All clinical studies presenting sufficient data on free-tissue transfer performed on short-term collaborative surgical trips (STCSTs) in LMICs will be eligible for inclusion. The primary outcomes are rate of free flap failure, rate of emergency return to theatre for free flap salvage and successful salvage rate. The secondary outcomes include postoperative complications, cost effectiveness, impact on training, burden of disease, legacy and any functional or patient reported outcome measures. Screening of studies, data extraction and assessments of study quality and bias will be conducted by two authors. Individual study quality will be assessed according to the Oxford Evidence-based Medicine Scales of Evidence 2, and risk of bias using either the 'Revised Cochrane risk of bias tool for randomized trials' (Rob2), the 'Risk of bias in non-randomized studies of interventions' (ROBINS-I) tool, or the National Institute for Health Quality Assessment tool for Case Series. Overall strength of evidence will be assessed according to the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

DISCUSSION

To-date the outcomes of microsurgical procedures performed on STCSTs to LMICs are largely unknown. Improved education, funding and allocation of resources are needed to support surgeons in LMICs to perform free-tissue transfer. STCSTs provide a vehicle for sustainable collaboration and training. Disseminating microsurgical skills could improve the care received by patients living with reconstructive pathology in LMICs, but this is poorly established. This study sets out a robust protocol for a systematic review designed to critically analyse outcomes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 225613.

Urethrographic examinations: Patient and staff exposures and associated radiobiological risks

Medical exposure of the general population due to radiological investigations is the foremost source of all artificial ionising radiation. Here, we focus on a particular diagnostic radiological procedure, as only limited data are published with regard to radiation measurements during urethrograpic imaging. Specifically, this work seeks to estimate patient and occupational effective doses during urethrographic procedures at three radiology hospitals. Both staff and patient X-ray exposure levels were calculated in terms of entrance surface air kerma (ESAK), obtained by means of lithium fluoride thermoluminescent dosimeters (TLD-100(LiF:Mg:Cu.P)) for 243 urethrographic examinations. Patient radiation effective doses per procedure were estimated using conversion factors obtained from the use of Public Health England computer software. In units of mGy, the median and range of ESAK per examination were found to be 10.8 (3.6-26.2), 7.0 (0.2-32.3), and 24.3 (9.0-32.0) in Hospitals A, B, and C, respectively. The overall mean and range of staff doses (in µGy) were found to be 310 (4.0-1750) per procedure. With the exception of hospital C, the present evaluations of radiation dose have been found to be similar to those of previously published research. The wide range of patient and staff doses illustrate the need for radiation dose optimisation.

Adjuvant Alendronic Acid in the Management of Severe Cherubism: A Case Report and Literature Review

Cherubism is a rare disease of the jaws characterized by bilateral symmetrical painless expansion of the mandible and maxilla. In extreme cases, larger lesions can become exophytic and have profound functional and esthetic implications. Several pharmacologic agents have been trialed in the treatment of cherubism with variable success reported. Bisphosphonates have not been significantly studied in this setting. We present a case where oral alendronic acid was used as an adjuvant treatment after surgical debulking of the maxilla in a 13-year-old boy with a severe case of cherubism.

Searching for meaning in sound: Learning and interpreting alarm signals in visual environments

Given the ease with which the diverse array of environmental sounds can be understood, the difficulties encountered in using auditory alarm signals on medical devices are surprising. In two experiments, with nonclinical participants, alarm sets which relied on similarities to environmental sounds (concrete alarms, such as a heartbeat sound to indicate "check cardiovascular function") were compared to alarms using abstract tones to represent functions on medical devices. The extent to which alarms were acoustically diverse was also examined: alarm sets were either acoustically different or acoustically similar within each set. In Experiment 1, concrete alarm sets, which were also acoustically different, were learned more quickly than abstract alarms which were acoustically similar. Importantly, the abstract similar alarms were devised using guidelines from the current global medical device standard (International Electrotechnical Commission 60601-1-8, 2012). Experiment 2 replicated these findings. In addition, eye tracking data showed that participants were most likely to fixate first on the correct medical devices in an operating theater scene when presented with concrete acoustically different alarms using real world sounds. A new set of alarms which are related to environmental sounds and differ acoustically have therefore been proposed as a replacement for the current medical device standard. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Recurrent Rathke's Cleft Cysts: Incidence and Surgical Management in a Tertiary Pituitary Center over 2 Decades

BACKGROUND

Limited data exist pertaining to outcomes following surgery for recurrent Rathke's cleft cysts (RCC).

OBJECTIVE

To determine treatment outcomes in patients undergoing reoperation for recurrent or residual RCCs.

METHODS

A retrospective analysis of 112 consecutive RCC operations in 109 patients between 1995 and 2017 was conducted.

RESULTS

Eighteen patients underwent 21 RCC reoperations with a mean follow-up of 58 mo. Patient symptoms prior to reoperation included headaches (14, 66.7%) and vision loss (12, 57.1%). Thirteen of 18 patients (72.2%) required hormone supplementation prior to reoperation including 5 with diabetes insipidus (DI). Mean RCC diameter was 16 mm and 76% had suprasellar extension. Compared to index RCC cases, intraoperative cerebrospinal fluid leak repair was more common in reoperation cases (15/21, 71% vs 43/91, 47%, P = .05). There was 1 carotid artery injury without neurological sequelae, and 2 postoperative cerebrospinal fluid (CSF) leaks (9.5%). Rates of transient hyponatremia (3/10, 30% vs 4/91, 4.4%, P = .04) and transient DI (5/10, 50% vs 17/91, 18.7%, P = .04) were higher in the reoperation vs index group. Improved headaches and vision were reported in 4/12 (33%) and 8/12 (61.5%) of RCC reoperation patients, respectively. Two patients developed new permanent DI. A higher proportion of reoperation patients had RCC squamous metaplasia (24% vs 5.4%, P = .02) or wall inflammation (42.9% vs 2.2%, P < .001) on pathological examination.

CONCLUSION

Reoperation for RCCs is generally safe at tertiary pituitary centers and often results in improved vision. Hypopituitarism is less likely to improve following reoperation for recurrent RCCs. Several histopathological features may help characterize "atypical RCCs" with a higher likelihood of recurrence/progression.

Evaluation of aldosterone antagonist utilization in heart failure with reduced and preserved ejection fraction at an academic medical center

Background:

Objective:

Methods:

Results:

Conclusions:

Non-invasive imaging of disrupted protein homeostasis induced by proteasome inhibitor treatment using chemical exchange saturation transfer MRI

Proteasome inhibitors (PIs) are now standard of care for several cancers, and noninvasive biomarkers of treatment response are critically required for early patient stratification and treatment personalization. The present study evaluated whether chemical exchange (CEST) magnetic resonance imaging (MRI) can provide measurements that can be used as the noninvasive biomarkers of proteasome inhibition, alongside diffusion MRI and relaxometry. The sensitivity of human colorectal carcinoma cells to the PI Ixazomib was assessed via in vitro and in vivo dose-response experiments. Acute in vivo response to Ixazomib was assessed at three dosing concentrations, using CEST MRI (amide, amine, hydroxyl signals), diffusion MRI (ADC) and relaxometry (T1, T2). These responses were further evaluated with the known histological markers for Ixazomib and Bradford assay ex vivo. The CEST signal from amides and amines increased in proportion to Ixazomib dose in colorectal cancer xenografts. The cell lines differed in their sensitivity to Ixazomib, which was reflected in the MRI measurements. A mild stimulation in tumor growth was observed at low Ixazomib doses. Our results identify CEST MRI as a promising method for safely and noninvasively monitoring disrupted tumor protein homeostasis induced by proteasome inhibitor treatment, and for stratifying sensitivity between tumor types.

Design and raytrace simulations of a multilayer-coated Wolter x-ray optic for the Z machine at Sandia National Laboratories

Recent breakthroughs in the fabrication of small-radii Wolter optics for astrophysics allow high energy density facilities to consider such optics as novel x-ray diagnostics at photon energies of 15-50 keV. Recently, the Lawrence Livermore National Laboratory, Sandia National Laboratories (SNL), the Smithsonian Astrophysical Observatory, and the NASA Marshall Space Flight Center jointly developed and fabricated the first custom Wolter microscope for implementation in SNL's Z machine with optimized sensitivity at 17.5 keV. To achieve spatial resolution of order 100-200 microns over a field of view of 5 × 5 × 5 mm³ with high throughput and narrow energy bandpass, the geometry of the optic and its multilayer required careful design and optimization. While the geometry mainly influences resolution and the field of view of the diagnostic, the mirror coating determines the spectral response and throughput. Here we outline the details of the design and fabrication process for the first multilayer-coated Wolter I optic for SNL's Z machine (Z Wolter), including its W/Si multilayer, and present results of raytrace simulations completed to predict and verify the performance of the optic.

Characterization and calibration of a multilayer coated Wolter optic for an imager on the Z-machine at Sandia National Laboratories

The need for a time-resolved monochromatic x-ray imaging diagnostic at photon energies >15 keV has motivated the development of a Wolter optic to study x-ray sources on the Z-machine at Sandia National Laboratories. The work is performed in both the LLNL's x-ray calibration facility and SNL's micro-focus x-ray lab. Characterizations and calibrations include alignment, measurement of throughput within the field of view (FOV), the point-spread function within the FOV both in and out of focus, and bandpass in the FOV. These results are compared with ray tracing models, showing reasonable agreement.

A Wolter imager on the Z machine to diagnose warm x-ray sources

A new Wolter x-ray imager has been developed for the Z machine to study the emission of warm (>15 keV) x-ray sources. A Wolter optic has been adapted from observational astronomy and medical imaging, which uses curved x-ray mirrors to form a 2D image of a source with 5 × 5 × 5 mm³ field-of-view and measured 60-300-μm resolution on-axis. The mirrors consist of a multilayer that create a narrow bandpass around the Mo Kα lines at 17.5 keV. We provide an overview of the instrument design and measured imaging performance. In addition, we present the first data from the instrument of a Mo wire array z-pinch on the Z machine, demonstrating improvements in spatial resolution and a 350-4100× increase in the signal over previous pinhole imaging techniques.

Sub-nanosecond single line-of-sight (SLOS) x-ray imagers (invited)

A new generation of fast-gated x-ray framing cameras have been developed that are capable of capturing multiple frames along a single line-of-sight with 30 ps temporal resolution. The instruments are constructed by integrating pulse-dilation electron imaging with burst mode hybrid-complimentary metal-oxide-semiconductor sensors. Two such instruments have been developed, characterized, and fielded at the National Ignition Facility and the OMEGA laser. These instruments are particularly suited for advanced x-ray imaging applications in Inertial Confinement Fusion and High energy density experiments. Here, we discuss the system architecture and the techniques required for tuning the instruments to achieve optimal performance. Characterization results are also presented along with planned future improvements to the design.

Long-term surgical outcomes following transsphenoidal surgery in patients with Rathke's cleft cysts

OBJECTIVE

Rathke's cleft cysts (RCCs) are benign epithelial lesions of the sellar region typically treated via a transsphenoidal approach with cyst fenestration and drainage. At present, there is limited evidence to guide patient selection for operative treatment. Furthermore, there is minimal literature describing factors contributing to cyst recurrence.

METHODS

The authors conducted a retrospective analysis of 109 consecutive cases of pathology-confirmed RCCs treated via a transsphenoidal approach at a single center from 1995 to 2016. The majority of cases (86.2%) involved cyst fenestration, drainage, and partial wall resection. Long-term outcomes were analyzed.

RESULTS

A total of 109 surgeries in 100 patients were included, with a mean follow-up duration of 67 months (range 3-220 months). The mean patient age was 44.6 years (range 12-82 years), and 73% were women. The mean maximal cyst diameter was 14.7 mm. Eighty-eight cases (80.7%) were primary operations, and 21 (19.3%) were reoperations. Intraoperative CSF leak repair was performed in 53% of cases and was more common in reoperation cases (71% vs 48%, p < 0.001). There were no new neurological deficits or perioperative deaths. Two patients (1.8%) developed postoperative CSF leaks. Transient diabetes insipidus (DI) developed in 24 cases (22%) and permanent DI developed in 6 (5.5%). Seven cases (6.4%) developed delayed postoperative hyponatremia. Of the 66 patients with preoperative headache, 27 (44.3%) of 61 reported postoperative improvement and 31 (50.8%) reported no change. Of 31 patients with preoperative vision loss, 13 (48.1%) reported subjective improvement and 12 (44.4%) reported unchanged vision. Initial postoperative MRI showed a residual cyst in 25% of cases and no evidence of RCC in 75% of cases. Imaging revealed evidence of RCC recurrence or progression in 29 cases (26.6%), with an average latency of 28.8 months. Of these, only 10 (9.2% of the total 109 cases) were symptomatic and underwent reoperation.

CONCLUSIONS

Transsphenoidal fenestration and drainage of RCCs is a safe and effective intervention for symptomatic lesions, with many patients experiencing improvement of headaches and vision. RCCs show an appreciable (although usually asymptomatic) recurrence rate, thereby mandating serial follow-up. Despite this, full RCC excision is typically not recommended due to risk of hypopituitarism, DI, and CSF leaks.

Pertuzumab, trastuzumab, and standard anthracycline- and taxane-based chemotherapy for the neoadjuvant treatment of patients with HER2-positive localized breast cancer (BERENICE): a phase II, open-label, multicenter, multinational cardiac safety study

Background

Anti-HER2 therapies are associated with a risk of increased cardiac toxicity, particularly when part of anthracycline-containing regimens. We report cardiac safety of pertuzumab, trastuzumab, and chemotherapy in the neoadjuvant treatment of HER2-positive early breast cancer.

Patients and methods

BERENICE (NCT02132949) is a nonrandomized, phase II, open-label, multicenter, multinational study in patients with normal cardiac function. In the neoadjuvant period, cohort A patients received four cycles of dose-dense doxorubicin and cyclophosphamide, then 12 doses of standard paclitaxel plus four standard trastuzumab and pertuzumab cycles. Cohort B patients received four standard fluorouracil/epirubicin/cyclophosphamide cycles, then four docetaxel cycles with four standard trastuzumab and pertuzumab cycles. The primary end point was cardiac safety during neoadjuvant treatment, assessed by the incidence of New York Heart Association class III/IV heart failure and of left ventricular ejection fraction declines (≥10 percentage-points from baseline and to a value of <50%). The main efficacy end point was pathologic complete response (pCR, ypT0/is ypN0). Results are descriptive.

Results

Safety populations were 199 and 198 patients in cohorts A and B, respectively. Three patients [1.5%; 95% confidence interval (CI) 0.31% to 4.34%] in cohort A experienced four New York Heart Association class III/IV heart failure events. Thirteen patients (6.5%; 95% CI 3.5% to 10.9%) in cohort A and four (2.0%; 95% CI 0.6% to 5.1%) in cohort B experienced at least one left ventricular ejection fraction decline. No new safety signals were identified. pCR rates were 61.8% and 60.7% in cohorts A and B, respectively. The highest pCR rates were in the HER2-enriched PAM50 subtype (75.0% and 73.7%, respectively).

Conclusion

Treatment with pertuzumab, trastuzumab, and common anthracycline-containing regimens for the neoadjuvant treatment of early breast cancer resulted in cardiac and general safety profiles, and pCR rates, consistent with prior studies with pertuzumab.

Clinical Trial Information

NCT02132949.

Abstract P5-20-04: Safety of adjuvant treatment with pertuzumab plus trastuzumab after neoadjuvant anthracycline-based chemotherapy in patients with HER2-positive localized breast cancer: Updated results from the BERENICE study

Background Anti-HER2 therapies are associated with a risk of cardiac toxicity, particularly as part of anthracycline-based regimens. BERENICE (NCT02132949), a nonrandomized, Phase 2 cardiac safety study showed neoadjuvant treatment with pertuzumab (P) + trastuzumab (H) and 2 common anthracycline–taxane-based regimens had a safety profile consistent with prior studies of P+H, and was associated with high pathologic complete response rates. Here we report safety data from the P+H adjuvant treatment period (AP).

Methods Patients (pts) with centrally confirmed, localized HER2-positive breast cancer and normal cardiac function received 4 q2w dose-dense doxorubicin and cyclophosphamide cycles (60/600mg/m2) then 12 qw paclitaxel injections (80mg/m2; Cohort A), or 4 q3w fluorouracil/epirubicin/cyclophosphamide cycles (500/100/600 mg/m2) then 4 q3w docetaxel cycles (75mg/m2, up to 100mg/m2;Cohort B). In both cohorts, 4 q3w cycles of P (loading:840mg; maintenance:420mg) + H (loading:8mg/kg; maintenance:6mg/kg) were started with taxane therapy and continued in the adjuvant setting (for up to 13 cycles to complete 1 year of treatment). Surgery was scheduled after 8 cycles of preoperative therapy. Primary endpoints were incidence of New York Heart Association (NYHA) Class III/IV heart failure and incidence of left ventricular ejection fraction (LVEF) declines (≥10%-points from baseline to &lt;50%; asymptomatic and symptomatic events) assessed by ECHO/MUGA. Confirmed LVEF declines were defined as significant LVEF declines at 2 consecutive visits.

Results In total, 397 pts received ≥1 dose of study medication and were included in the overall treatment period (OTP) safety analysis. Of these, 371 (Cohort A:181; Cohort B:190) pts entered the AP and were included in the AP safety analysis. Mean (SD) number of AP treatment cycles of P and H were 12.3 (2.0) in Cohort A and 12.3 (2.2) in Cohort B. In the AP, incidence of heart failure was minimal (0.5%) and confirmed LVEF decline incidence was low (Table 1).

Table 1: Cardiac AE Cohort ACohort B OTP n=199AP n=181OTP n=198OTP n=190NYHA Class III/IV heart failure    Events, n4011Pts with event, n (%)3(1.5)01(0.5)1(0.5)LVEF decline    Events, n36223429Pts with LVEF decline, n (%)21(10.6)14(7.7)22(11.1)20(10.5)Pts with confirmed LVEF decline, n (%)7(3.5)5(2.8)7(3.5)6(3.2)

General adverse events (AEs) are shown in Table 2; 26 (14.4%) pts in Cohort A and 45 (23.7%) in Cohort B had diarrhea AEs (mostly grade 1).

Table 2: General AE Cohort ACohort BPts, n (%)OTP n=199AP n=181OTP n=198AP n=190Any AE198(99.5)171(94.5)198(100.0)171(90.0)Grade ≥3 AE109(54.8)23(12.7)126(63.6)40(21.1)Serious AE54(27.1)15(8.3)61(30.8)17(8.9)AE leading to P or H discontinuation19(9.5)9(5.0)14(7.1)11(5.8)

Conclusion P+H in the adjuvant setting, following P+H with anthracycline-based regimens in the neoadjuvant setting, are associated with low incidence of cardiac AEs. Cardiac safety results for P+H in the AP and OTP of BERENICE were consistent with results from prior studies evaluating adjuvant treatment with single-agent H, suggesting the addition of P to H in the adjuvant setting does not increase cardiac toxicity.

Citation Format: Dang C, Ewer MS, Delaloge S, Ferrero J-M, Verrill M, Colomer R, Vieira C, de la Cruz Merino L, Lucas J, Werner TL, Douthwaite H, Bradley D, Waldron-Lynch M, Eng-Wong J, Swain SM. Safety of adjuvant treatment with pertuzumab plus trastuzumab after neoadjuvant anthracycline-based chemotherapy in patients with HER2-positive localized breast cancer: Updated results from the BERENICE study [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 P5-20-04.

Patient Exposure during Fluoroscopy-guided Pacemaker Implantation Procedures

A pacemaker, which is used for heart resynchronization with electrical impulses, is used to manage many clinical conditions. Recently, the frequency of pacemaker implantation procedures has increased to more than 50% worldwide. During this procedure, patients can be exposed to excessive radiation exposure. Wide range of doses has been reported in previous studies, suggesting that optimization of this procedure has not been fulfilled yet. The current study evaluated patient radiation exposure during cardiac pacemaker procedures and quantified the patient effective dose. A total of 145 procedures were performed for five pacemaker procedures (VVI, VVIR, VVD, VVDR, and DDDR) at two hospitals. Patient doses were measured using the kerma-area product meter. Effective doses were estimated using software based on Monte Carlo simulation from the National Radiological Protection Board (NRPB, now The Health Protection Agency). The effective dose values were used to estimate cancer risk from the pacemaker procedure. Patient demographic data and exposure parameters for fluoroscopy and radiography were quantified. The mean patient doses ± SD per procedure (Gycm²) for VVI, VVIR, VVD, VVDR, and DDDR were 1.52 ± 0.13 (1.43-1.61), 3.28 ± 2.34 (0.29-8.73), 3.04 ± 1.67 (1.57-4.86), 6.04 ± 2.326 3.29-8.58), and 8.8 ± 3.6 (4.5-26.20), respectively. The overall patient effective dose was 1.1mSv per procedure. It is obvious that the DDDR procedure exposed patients to the highest radiation dose. Patient dose variation can be attributed to procedure type, exposure parameter settings, and fluoroscopy time. The results of this study showed that patient doses during different pacemaker procedures are lower compared to previous reported values. Patient risk from pacemaker procedure is low, compared to other cardiac interventional procedures. Patients' exposures were mainly influenced by the type of procedures and the clinical indication.

Estimation of effective dose and radiation risk in pediatric barium studies procedures

The objectives of this study are to assess pediatric radiation exposure in certain barium studies and to quantify the organ and effective doses and radiation risk resultant from patients' irradiation. A total of 69 pediatric barium studies for upper and lower gastrointestinal tract. Patients' radiation dose was quantified in terms of Entrance surface air kerma (ESAKs) using exposure parameters and DosCal software. Organ and effective doses (E) were extrapolated using national Radiological Protection Board software (NRPB-R279). The mean ± (SD) and the range of patient doses per procedure were 3.7 ± 0.4 (1.0-13.0)mGy, 7.4 ± 1.7(5.5-8.0)mGy and 1.4 ± 0.9 (0.5-3.6)mGy for barium meal, swallow and enema, respectively. The mean effective doses were 0.3 ± 0.03 (0.08-1.1)mSv, 0.2 ± 1.6 (0.44-0.7)mSv and 0.3 ± 0.9 (0.1-0.8)mSv at the same order. The radiation dose were higher compared to previous studies. Therefore, pediatrics are exposed to avoidable radiation exposure. Certain optimization measures are recommended along with establishing national diagnostic reference level (DRL) to reduce the radiation risk.

Tolerability of up to 200 days of prophylaxis with valganciclovir oral solution and/or film-coated tablets in pediatric kidney transplant recipients at risk of cytomegalovirus disease

This multicenter, open-label study evaluated the tolerability of extended prophylaxis with valganciclovir in pediatric kidney transplant recipients at risk of CMV disease. Fifty-six patients aged 4 months to 16 years received once-daily valganciclovir oral solution and/or tablets, dosed by BSA and renal function, for up to 200 days. The most common AEs on treatment were upper respiratory tract infection (33.9%), urinary tract infection (33.9%), diarrhea (32.1%), leukopenia (25.0%), neutropenia (23.2%), and headache (21.4%). There were fewer AEs during days 101-228 vs days 1-100. Twenty-seven patients (48.2%) had treatment-related AEs during valganciclovir treatment, most commonly leukopenia (21.4%), neutropenia (19.6%), anemia (7.1%), and tremor (5.4%). Treatment-related serious AEs were reported for nine patients (16.1%) and six withdrew due to AEs. Viremia was centrally confirmed in 10 patients; there was no confirmed CMV disease. One patient tested positive for a resistance mutation (UL97 L595F). Biopsy-proven acute rejection occurred in six patients (10.7%), but no graft loss or deaths occurred. In conclusion, up to 200 days of valganciclovir prophylaxis in pediatric kidney allograft recipients showed a safety profile consistent with that established in adult transplant patients.

The National Ignition Facility modular Kirkpatrick-Baez microscope

Current two-dimensional X-ray imaging at the National Ignition Facility (NIF) uses time resolved pinhole cameras with ∼10-25 μm pinholes. This method has limitations in the smallest resolvable features that can be imaged with reasonable photon statistics for inertial confinement fusion (ICF) applications. ICF sources have a broadband self-emission spectrum that causes the pinhole images obtained, through thin foil filters, to contain a similarly broadband spectrum complicating the interpretation of structure in the source. In order to study phenomena on the scale of ∼5 μm, such as dopant mix in the ICF capsule, a narrow energy band, higher spatial resolution microscope system with improved signal/noise has been developed using X-ray optics. Utilizing grazing incidence mirrors in a Kirkpatrick-Baez microscope (KBM) configuration [P. Kirkpatrick and A. V. Baez, J. Opt. Soc. Am. 38, 766-774 (1948)], an X-ray microscope has been designed and fielded on NIF with four imaging channels. The KBM has ∼12 × magnification, <8 μm resolution, and higher throughput in comparison to similar pinhole systems. The first KBM mirrors are coated with a multilayer mirror to allow a "narrow band" energy response at 10.2 keV with ΔE ∼ 3 keV. By adjusting the mirror coating only, the energy response can be matched to the future experimental requirements. Several mirror packs have been commissioned and are interchangeable in the diagnostic snout.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

Abstract LB-185: A dual-isotope 3D cryo-imaging quantitative autoradiography (CIQA) method for simultaneous and quantitative assessment of both antibody and drug conjugate tumor distribution and kinetics

Antibody-drug conjugates (ADCs) are optimized extensively in in vitro studies. Including drug-conjugate selection, linker stability and antibody affinity, most ADC characteristics have been studied to improve affinity, stability, efficacy and the bystander effect. Most nuclear medicine molecular imaging modalities’ resolution is too low to enable accurate in vivo intratumoral tracer distribution analysis. Thus, they have focused on understanding in vivo PK profiles and antigen-dependent tumor accumulation. We set out to develop a novel method for studying the intratumoral distribution of both antibody and drug conjugate simultaneously ex vivo.

MLN0264, an ADC targeting guanylyl cyclase C (GCC) currently in phase 2 clinical trials (NCT02391038), was labeled with both 3H (MMAE drug conjugate) and 111In (DTPA-mAb) and injected into GCC-positive (GCC-293) and GCC-negative (HEK-293) subcutaneous tumor bearing female SCID mice. The tumors were excised 1, 8, 24, and 96 hours post injection (n = 2 per tumor line per time point), blocked and sectioned (30 μm) for analysis. High resolution optical images were acquired for all sections and every 10th section was evaluated for radioactivity content via autoradiography, first to evaluate the distribution of 111In immediately after tumor excision and again following 111In decay to evaluate the 3H-specific signal. Analysis of accumulation, distribution and overlap of the two signals enables the estimation of antigen-mediated metabolism of the ADC, the tumoral distribution of the drug metabolites and the time course of the bystander effect (Fig 1A). The distribution of 3H and 111In signals at 1 h was very similar for the two cell lines. At 24 and 96 hours, substantial differences in the co-localization of signals were observed between the antigen-positive and antigen-negative tumors. Quantitatively, of the top 3% of pixel values in the 3H and 111In images at 96 hours, only 0.8% of GCC-293 tumor voxels shows an overlap of signals while over 15% of voxels in the HEK-293 tumors express both signals suggesting increased ADC metabolism and bystander effect in antigen positive tumors (Fig 1B).

Cryo-Imaging Quantitative Autoradiography (CIQA) is a novel technique to extend conventional autoradiography by combining it with digital imaging and advanced 3D image analysis. For the first time, we demonstrate here the use of CIQA to quantify and visualize the two major components of an ADC, the mAb and small molecule drug simultaneously in three dimensions over time (4D). We believe this powerful and unique tool will allow for increased insight into the influence of ADC properties on tumor spatial distribution, in vivo bystander effect, off-target ADC metabolism and correlation of 3D distribution and heterogeneity with immunohistochemical markers to enable more accurate pharmacodynamic profiles.

Citation Format: Ohad Ilovich, Mohammed Qutaish, Jacob Hesterman, Kelly Orcutt, Jack Hoppin, Ildiko Polyak, Marc Seaman, Paige Czarnecki, Vijay Gottumukkala, Mihaela Plesescu, Ozlem Yardibi, Daniel Bradley. A dual-isotope 3D cryo-imaging quantitative autoradiography (CIQA) method for simultaneous and quantitative assessment of both antibody and drug conjugate tumor distribution and kinetics. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-185.

First high-convergence cryogenic implosion in a near-vacuum hohlraum

Recent experiments on the National Ignition Facility [M. J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] demonstrate that utilizing a near-vacuum hohlraum (low pressure gas-filled) is a viable option for high convergence cryogenic deuterium-tritium (DT) layered capsule implosions. This is made possible by using a dense ablator (high-density carbon), which shortens the drive duration needed to achieve high convergence: a measured 40% higher hohlraum efficiency than typical gas-filled hohlraums, which requires less laser energy going into the hohlraum, and an observed better symmetry control than anticipated by standard hydrodynamics simulations. The first series of near-vacuum hohlraum experiments culminated in a 6.8 ns, 1.2 MJ laser pulse driving a 2-shock, high adiabat (α∼3.5) cryogenic DT layered high density carbon capsule. This resulted in one of the best performances so far on the NIF relative to laser energy, with a measured primary neutron yield of 1.8×10(15) neutrons, with 20% calculated alpha heating at convergence ∼27×.

AXIS: an instrument for imaging Compton radiographs using the Advanced Radiography Capability on the NIF

Compton radiography is an important diagnostic for Inertial Confinement Fusion (ICF), as it provides a means to measure the density and asymmetries of the DT fuel in an ICF capsule near the time of peak compression. The AXIS instrument (ARC (Advanced Radiography Capability) X-ray Imaging System) is a gated detector in development for the National Ignition Facility (NIF), and will initially be capable of recording two Compton radiographs during a single NIF shot. The principal reason for the development of AXIS is the requirement for significantly improved detection quantum efficiency (DQE) at high x-ray energies. AXIS will be the detector for Compton radiography driven by the ARC laser, which will be used to produce Bremsstrahlung X-ray backlighter sources over the range of 50 keV-200 keV for this purpose. It is expected that AXIS will be capable of recording these high-energy x-rays with a DQE several times greater than other X-ray cameras at NIF, as well as providing a much larger field of view of the imploded capsule. AXIS will therefore provide an image with larger signal-to-noise that will allow the density and distribution of the compressed DT fuel to be measured with significantly greater accuracy as ICF experiments are tuned for ignition.

A Kirkpatrick-Baez microscope for the National Ignition Facility

Current pinhole x ray imaging at the National Ignition Facility (NIF) is limited in resolution and signal throughput to the detector for Inertial Confinement Fusion applications, due to the viable range of pinhole sizes (10-25 μm) that can be deployed. A higher resolution and throughput diagnostic is in development using a Kirkpatrick-Baez microscope system (KBM). The system will achieve <9 μm resolution over a 300 μm field of view with a multilayer coating operating at 10.2 keV. Presented here are the first images from the uncoated NIF KBM configuration demonstrating high resolution has been achieved across the full 300 μm field of view.