Congenital Cytomegalovirus Testing Outcomes From the ValEAR Trial

OBJECTIVE

To determine the positivity rate of congenital cytomegalovirus (cCMV) testing among universal, hearing-targeted CMV testing (HT-cCMV) and delayed targeted dried blood spot (DBS) testing newborn screening programs, and to examine the characteristics of successful HT-cCMV testing programs.

STUDY DESIGN

Prospective survey of birth hospitals performing early CMV testing.

SETTING

Multiple institutions.

METHODS

Birth hospitals participating in the National Institutes of Health ValEAR clinical trial were surveyed to determine the rates of cCMV positivity associated with 3 different testing approaches: universal testing, HT-cCMV, and DBS testing. A mixed methods model was created to determine associations between successful HT-cCMV screening and specific screening protocols.

RESULTS

Eighty-two birth hospitals were surveyed from February 2019 to December 2021. Seven thousand six hundred seventy infants underwent universal screening, 9017 infants HT-cCMV and 535 infants delayed DBS testing. The rates of cCMV positivity were 0.5%, 1.5%, and 7.3%, respectively. The positivity rate for universal CMV screening was less during the COVID-19 pandemic than that reported prior to the pandemic. There were no statistically significant drops in positivity for any approach during the pandemic. For HT-cCMV testing, unique order sets and rigorous posttesting protocols were associated with successful screening programs.

CONCLUSION

Rates of cCMV positivity differed among the 3 approaches. The rates are comparable to cohort studies reported in the literature. Universal CMV prevalence decreased during the pandemic but not significantly. Institutions with specific order set for CMV testing where the primary care physician orders the test and the nurse facilitates the testing process exhibited higher rates of HT-cCMV testing.

Escalating Surgical Treatment for Left Ventricular Assist Device Infection and Expected Mortality: Clinical Risk Prediction Score

BACKGROUND

Left ventricular assist devices (LVAD) improve survival for patients with cardiac failure, but LVAD specific infections (VSI) remain a challenge with poorly understood predictive risk factors. Furthermore, the indications and utility of escalating medical treatment to surgical debridement and potential flap reconstruction are not well-characterized.

STUDY DESIGN

A retrospective review of consecutive patients undergoing primary LVAD implantation at a tertiary academic center was performed. The primary outcomes measures were 90-day and overall mortality after VSI. Cox proportional hazards regression was used to generate a risk-prediction score for mortality.

RESULTS

Of the 760 patients undergoing primary LVAD implantation, 255 (34%) developed VSI; of these 91 (36%) were managed medically, 134 (52%) with surgical debridement, and 30 (12%) with surgical debridement and flap reconstruction. One-year survival after infection was 85% with median survival of 2.40 years. Factors independently associated with increased mortality were diabetes (hazard ratio (HR) 1.44, p=0.04), methicillin-resistant Staphylococcus aureus infection (HR 1.64, p=0.03), deep space (pump pocket/outflow cannula) involvement (HR 2.26, p<0.001) and extra-corporeal membrane oxygenation after LVAD (HR 2.52, p<0.01. Factors independently associated with decreased mortality were flap reconstruction (HR 0.49, p=0.02) and methicillin-sensitive Staphylococcus aureus infection (HR 0.63, p=0.03). A clinical risk prediction score was developed using these factors and showed significant differences in median survival, which was 5.67 years for low-risk (score 0-1), 3.62 years for intermediate-risk (score 2), and 1.48 years for high-risk (score >3) (p<0.001) patients.

CONCLUSIONS

We developed a clinical risk prediction score to stratify VSI patients. In selected cases, escalating surgical treatment was associated with increased survival. Future work is needed to determine if early surgical debridement and flap reconstruction can alter outcomes in select cases of VSI.

Free functional muscle transfer for lower extremity reconstruction

BACKGROUND

Free functional muscle transfer is a reconstructive strategy for the reconstruction of lost muscle units in the lower extremity after oncologic resection, trauma, compartment syndrome, or severe nerve injuries. Under appropriate circumstances, free functional muscle transfer may be the only suitable reconstructive option. This article reviews the underlying principles of free functional muscle transfer, its application to lower extremity reconstruction, appropriate patient selection, and surgical techniques.

METHODS

The underlying principles of free functional muscle transfer, its application to lower extremity reconstruction, appropriate patient selection, and surgical techniques are presented. Commonly used donor muscles appropriate for each type of functional defect are discussed. A review of recent publications on free functional muscle transfer in the lower extremity was also performed.

RESULTS

Good functional recovery with a Medical Research Council grade of up to 4/5 and full range of motion can be attained with free functional muscle transfer. Clinical outcomes and specific parameters for published case series in lower extremity free functional muscle transfer are presented and an illustrative case.

CONCLUSION

Free functional muscle transfer is a suitable treatment for the appropriate patient to restore essential functions and potentially regain ambulation. However, additional published clinical outcomes are needed and represent a major area for further investigation.

Utility of Intraoperative Radiographs in Pediatric Cochlear Implant Surgery

OBJECTIVE

To evaluate the role of intraoperative radiographs to confirm electrode position following pediatric cochlear implantation (CI).

STUDY DESIGN

Retrospective chart review.

SETTING

Single tertiary care pediatric center.

METHODS

A retrospective chart review was conducted, including all pediatric patients undergoing CI at UPMC Children's Hospital of Pittsburgh over a 13-year period.

RESULTS

We identified 326 patients undergoing 492 procedures. Across the cohort, there were 7 cases that required intraoperative electrode reinsertion due to malposition or presumed malposition. For 6 of the 7 cases, intraoperative X-ray identified electrode malposition. Neural response telemetry (NRT) testing was also abnormal for 4 of these cases prior to reinsertion. Implantation of Cochlear's Slim Modiolar electrode was associated with an abnormal perioperative X-ray (odds ratio [OR]: 9.2, p = 0.03) and increased change in management (OR: 9.2, p = 0.03) compared to Cochlear's Contour Advance (CA). Incidence of abnormal X-rays was 1.24% overall, 4% in the Slim Modiolar group, and 0.3% in the CA group. The Slim Modiolar electrode accounted for 4 of 7 cases requiring reinsertion, and in all 4 of these cases, electrode fold-over was identified on the X-ray. NRT was normal in 1 of these 4 cases.

CONCLUSION

The use of Cochlear's Slim Modiolar electrode was associated with a significantly increased risk of abnormal intraoperative X-ray compared to the CA electrode. Given the risk of fold-over with routine insertion and normal electrical testing using the Slim Modiolar electrode, we recommend routine use of intraoperative skull X-ray to confirm electrode position.

A Surgical Framework for the Management of Incomplete Axillary Nerve Injuries

BACKGROUND

 Axillary nerve injury is the most common nerve injury affecting shoulder function. Nerve repair, grafting, and/or end-to-end nerve transfers are used to reconstruct complete neurotmetic axillary nerve injuries. While many incomplete axillary nerve injuries self-resolve, axonotmetic injuries are unpredictable, and incomplete recovery occurs. Similarly, recovery may be further inhibited by superimposed compression neuropathy at the quadrangular space. The current framework for managing incomplete axillary injuries typically does not include surgery.

METHODS

 This study is a retrospective analysis of 23 consecutive patients with incomplete axillary nerve palsy who underwent quadrangular space decompression with additional selective medial triceps to axillary end-to-side nerve transfers in 7 patients between 2015 and 2019. Primary outcome variables included the proportion of patients with shoulder abduction M3 or greater as measured on the Medical Research Council (MRC) scale, and shoulder pain measured on a Visual Analogue Scale (VAS). Secondary outcome variables included pre- and postoperative Disabilities of the Arm, Shoulder, and Hand Questionnaire (DASH) scores.

RESULTS

 A total of 23 patients met the inclusion criteria and underwent nerve surgery a mean 10.7 months after injury. Nineteen (83%) patients achieved MRC grade 3 shoulder abduction or greater after intervention, compared with only 4 (17%) patients preoperatively (p = 0.001). There was a significant decrease in VAS shoulder pain scores of 4.2 ± 2.5 preoperatively to 1.9 ± 2.4 postoperatively (p < 0.001). The DASH scores also decreased significantly from 48.8 ± 19.0 preoperatively to 30.7 ± 20.4 postoperatively (p < 0.001). Total follow-up was 17.3 ± 4.3 months.

CONCLUSION

 A surgical framework is presented for the appropriate diagnosis and surgical management of incomplete axillary nerve injury. Quadrangular space decompression with or without selective medial triceps to axillary end-to-side nerve transfers is associated with improvement in shoulder abduction strength, pain, and DASH scores in patients with incomplete axillary nerve palsy.

Mechanism matters: A 10-year experience of ballistic injuries of the upper extremity

INTRODUCTION

Upper Extremity gunshot wounds represent a significant strain on community and hospital resources, and reports of their epidemiology are varied. We hypothesized that demographic and socioeconomic variables would be associated with variable injury patterns and management, and that two distinct populations would be affected by upper extremity ballistic injury based on violent versus accidental, self-inflicted mechanism.

MATERIALS & METHODS

Retrospective review of all adult patients sustaining ballistic injury to the upper extremity at a single urban Level I trauma center over 10 years (n = 797). Demographic, injury pattern, treatment, and outcomes data were collected. Comparisons between groups were conducted with unpaired t-tests and chi-square testing where appropriate.

RESULTS

Most patients were male (89.1%) and mean age was 30.1 years (18-83). Violence accounted for 89.1% of injuries. Black individuals were disproportionately affected at 87% of patients. Shoulder injuries were most common (34%), and wrist least common (7%). Demographics and injury pattern varied significantly between patients sustaining violent injury and those with self-inflicted mechanisms. Patients sustaining violent injury were most often young, Black men more likely to be injured proximally, whereas patients with self-inflicted injuries were more likely to be older, Caucasian men with more comorbidities injured distally. Cumulatively, 35.3% of patients required operative intervention. Distal injuries were more likely operative. The most commonly injured structure across all levels was bone (53%), and 54.3% of fractures required operation. Median follow-up was 24.5 months. Complication rate was 13.6%.

CONCLUSIONS

Gunshot wounds of the upper extremity create complex patterns of injury which vary based on level of injury and mechanism. Violent and self-inflicted injuries occur in dissimilar populations and result in distinctive injury patterns.

Antibiotic Prophylaxis and Infectious Complications in Isolated Gunshot Wounds to the Upper Extremity

BACKGROUND

Prophylactic antibiotics are variably prescribed after isolated upper extremity gunshot wounds (UE GSWs). The risk of infection and factors influencing prescribing practice remain poorly understood, and clinical practice guidelines are lacking.

METHODS

Adults with isolated UE GSWs over a 10-year period were included. Medical records were reviewed for demographic and injury variables, comorbidities, surgical treatments, antibiotic administration, infectious complications, and follow-up duration. Infection rate was calculated. Bivariate and multivariable linear regression analyses were used to identify patient-related and injury-related factors predictive of prophylactic antibiotic prescription.

RESULTS

A total of 281 patients were eligible for inclusion. Prophylactic antibiotics were prescribed at discharge for 111 patients (40%). Multivariable analysis revealed that patients with more distal injuries and ballistic fractures were significantly more likely to receive prophylactic antibiotics. Of patients with at least 30-day postinjury follow-up, 6% developed infections.

CONCLUSION

Prophylactic antibiotic administration after UE GSWs was inconsistent but more common in patients with ballistic fractures and injuries in the hand. The overall incidence of infection was found to lie between 3% and 6%. The rate of infection in the antibiotic prophylaxis (2%-6%) group was similar to that in the no-antibiotic (5%-7%) group, suggesting that antibiotic prophylaxis may not have a large impact on infectious risk. However, because this study is nonrandomized, and because this study is underpowered for multivariable modeling of infectious risk, it remains possible that subgroups of this population may still benefit from antibiotic prophylaxis.

A multi-institutional survey on calvarial vault remodeling techniques for sagittal synostosis and outcomes analysis for patients treated at 12 months and older

OBJECTIVE

Surgical treatment of sagittal craniosynostosis is challenging in older patients. This study aimed to assess the effect of increasing age on open surgical technique selection and patient outcomes using the multi-institutional Synostosis Research Group (SynRG) collaboration.

METHODS

Surgeons in SynRG were surveyed for key influences on their preferred open calvarial vault remodeling techniques at various patient ages: < 6, 6-12, and > 12 months. The SynRG database was then queried for open repairs of nonsyndromic sagittal craniosynostosis performed for patients older than 12 months of age. Perioperative measures, complications, and preoperative and postoperative cephalic indices were reviewed.

RESULTS

All surgeons preferred to treat patients at an earlier age, and most (89%) believed that less-optimal outcomes were achieved at ages older than 12 months. The modified pi procedure was the dominant technique in those younger than 12 months, while more involved open surgical techniques were performed for older patients, with a wide variety of open calvarial vault remodeling techniques used. Forty-four patients met inclusion criteria, with a mean (± SD) age at surgery of 29 ± 16 months. Eleven patients underwent parietal reshaping, 10 parietal-occipital switch, 9 clamshell craniotomy, 7 geometric parietal expansion, 6 modified pi procedure, and 1 parietal distraction. There were no readmissions, complications, or mortality within 30 days postoperatively. Patients' cephalic indices improved a mean of 6.4% ± 4.0%, with a mean postoperative cephalic index of 74.2% ± 4.9%. Differences in postoperative cephalic index (p < 0.04) and hospital length of stay (p = 0.01) were significant between technique cohorts. Post hoc Tukey-Kramer analysis identified the parietal reshaping technique as being significantly associated with a reduced hospital length of stay.

CONCLUSIONS

Patient age is an important driver in technique selection, with surgeons selecting a more involved calvarial vault remodeling technique in older children. A variety of surgical techniques were analyzed, with the parietal reshaping technique being significantly associated with reduced length of stay; however, multiple perioperative factors may be contributory and require further analysis. When performed at high-volume centers by experienced pediatric neurosurgeons and craniofacial surgeons, open calvarial vault techniques can be a safe method for treating sagittal craniosynostosis in older children.

Abstract 78: Detection of gene fusions and exon skipping events in lung FFPE samples with Oncomine Precision Assay on Ion Torrent Genexus࣪ System

Introduction: Gene fusions and exon skipping events play an important oncogenic role in non-small cell lung cancer (NSCLC). Here we employed the Oncomine Precision Assay (OPA) for sequencing of 998 clinical research FFPE (Formalin-Fixed Paraffin-Embedded) lung samples using the Genexus࣪ integrated sequencing platform. The RNA assay strategy is aimed at providing a wide scope for studying known oncogenic fusions and exon skip variants, as well as a method for detection of novel fusion combinations and detection of fusions in a partner agnostic manner. We summarize the findings that include detected samples with oncogenic fusions in tyrosine kinase genes ALK, RET, ROS1 as well as MET exon14 skipping, and demonstrate the novel fusion detection capabilities of the panel.

Methods: The Oncomine Precision Assay panel developed using the Ion AmpliSeq HD technology for use on both tissue and liquid biopsy samples to detect fusions with high sensitivity in low input RNA. The panel features 981 known fusion isoforms in 16 oncogenic drivers as well as assays for exon skipping and deletion in MET and EGFR. The amplicons are strategically designed around known fusion breakpoints and generate reads only if the variant is present. Results are assessed bioinformatically with a framework that includes detailed genomic annotations of the fusion breakpoint, and generates interpretable fusion calls and report in the Genxus࣪ software. In addition, the panel contains an algorithm for novel fusion detection, and 78 exon-junction amplicons for partner agnostic fusion detection in ALK, RET, NTRK1,2,3 and FGFR1,2,3 with an exon tiling expression imbalance assay. We used the Genexus࣪ instrument to sequence 998 unique lung FFPE samples and analyzed the results with the Genexus࣪ fusion analysis workflow.

Results: A total of 998 unique lung FFPEs were sequenced, of which 906 (91%) resulted with &gt;5000 aligned reads and at least 5 of the 7 RNA expression controls at the assay threshold. A total of 25 samples with ALK fusions were detected by either the targeted fusions or the expression imbalance assays. In addition, we detected 10 samples with RET fusions, 4 with FGFR3 fusions, 3 with ROS1 fusions, and additional single observations of NRG1, RSPO3 and FGFR1 fusions. Exon 14 skipping in MET was detected in 14 samples, of which we were able to detect a likely splice site variant SNV or indel at, or near the boundaries of exon 14, with the DNA assays of the panel. These variants were observed in a mutually exclusive set of 59 total samples (6.5% of the samples).

Conclusions: We used the OPA panel for fusions and intragenic rearrangements that retains the simple workflow and fast turn-around time of previous Oncomine fusion, and demonstrated known and novel fusion detection as well exon skip variant detection capabilities in a research cohort of lung FFPE samples. For research use only. Not for use in diagnostic procedures.

Citation Format: Amir Marcovitz, Jeoffrey Schageman, Jian Gu, Stephen Wunsch, David Chi, Paul D. williams, Scott P. Myrand, Fiona C. Hyland, Seth Sadis, Kelli S. Bramlett. Detection of gene fusions and exon skipping events in lung FFPE samples with Oncomine Precision Assay on Ion Torrent Genexus࣪ System [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 78.

Complete Foot Drop With Normal Electrodiagnostic Studies: Sunderland "Zero" Ischemic Conduction Block of the Common Peroneal Nerve

ABSTRACT

Common peroneal neuropathy is a peripheral neuropathy of multifactorial etiology often left undiagnosed until foot drop manifests and electrodiagnostic abnormalities are detected. However, reliance on such striking symptoms and electrodiagnostic findings for diagnosis stands in contrast to other commonly treated neuropathies, such as carpal tunnel and cubital tunnel syndrome. Poor recognition of common peroneal neuropathy without foot drop or the presence of foot drop with normal electrodiagnostic studies thus often results in delayed or no surgical treatment. Our cases document 2 patients presenting with complete foot drop who had immediate resolution after decompression. The first patient presented with normal electrodiagnostic studies representing an isolated Sunderland Zero nerve ischemia. The second patient presented with severe electrodiagnostic studies but also had an immediate improvement in their foot drop representing a Sunderland VI mixed nerve injury with a significant contribution from an ongoing Sunderland Zero ischemic conduction block. In support of recent case series, these patients demonstrate that common peroneal neuropathy can present across a broad diagnostic spectrum of sensory and motor symptoms, including with normal electrodiagnostic studies. Four clinical subtypes of common peroneal neuropathy are presented, and surgical decompression may thus be indicated for these patients that lack the more conventional symptoms of common peroneal neuropathy.

Antioxidative and Angiogenic Hyaluronic Acid-Based Hydrogel for the Treatment of Peripheral Artery Disease

Peripheral arterial disease (PAD) is a progressive atherosclerotic disorder characterized by blockages of the arteries supplying the lower extremities. Ischemia initiates oxidative damage and mitochondrial dysfunction in the legs of PAD patients, causing injury to the tissues of the leg, significant decline in walking performance, leg pain while walking, and in the most severe cases, nonhealing ulcers and gangrene. Current clinical trials based on cells/stem cells, the trophic factor, or gene therapy systems have shown some promising results for the treatment of PAD. Biomaterial matrices have been explored in animal models of PAD to enhance these therapies. However, current biomaterial approaches have not fully met the essential requirements for minimally invasive intramuscular delivery to the leg. Ideally, a biomaterial should present properties to ameliorate oxidative stress/damage and failure of angiogenesis. Recently, we have created a thermosensitive hyaluronic acid (HA) hydrogel with antioxidant capacity and skeletal muscle-matching stiffness. Here, we further optimized HA hydrogels with the cell adhesion peptide RGD to facilitate the development of vascular-like structures in vitro. The optimized HA hydrogel reduced intracellular reactive oxygen species levels and preserved vascular-like structures against H₂O₂-induced damage in vitro. HA hydrogels also provided prolonged release of the vascular endothelial growth factor (VEGF). After injection into rat ischemic hindlimb muscles, this VEGF-releasing hydrogel reduced lipid oxidation, regulated oxidative-related genes, enhanced local blood flow in the muscle, and improved running capacity of the treated rats. Our HA hydrogel system holds great potential for the treatment of the ischemic legs of patients with PAD.

Impact of Patient Socioeconomic Disparities on Time to Tympanostomy Tube Placement

OBJECTIVES

Extensive literature exists documenting disparities in access to healthcare for patients with lower socioeconomic status (SES). The objective of this study was to examine access disparities and differences in surgical wait times in children with the most common pediatric otolaryngologic surgery, tympanostomy tubes (TT).

METHODS

A retrospective cohort study was performed at a tertiary children's hospital. Children ages <18 years who received a first set of tympanostomy tubes during 2015 were studied. Patient demographics and markers of SES including zip code, health insurance type, and appointment no-shows were recorded. Clinical measures included risk factors, symptoms, and age at presentation and first TT.

RESULTS

A total of 969 patients were included. Average age at surgery was 2.11 years. Almost 90% were white and 67.5% had private insurance. Patients with public insurance, ≥1 no-show appointment, and who lived in zip codes with the median income below the United States median had a longer period from otologic consult and preoperative clinic to TT, but no differences were seen in race. Those with public insurance had their surgery at an older age than those with private insurance (P < .001) and were more likely to have chronic otitis media with effusion as their indication for surgery (OR: 1.8, 95% CI: 1.2-2.5, P = .003).

CONCLUSIONS

Lower SES is associated with chronic otitis media with effusion and a longer wait time from otologic consult and preoperative clinic to TT placement. By being transparent in socioeconomic disparities, we can begin to expose systemic problems and move forward with interventions.

LEVEL OF EVIDENCE

4.

Hospital volume is associated with cost and outcomes variation in 2,942 pelvic reconstructions

BACKGROUND

Complex pelvic reconstruction is challenging for plastic and reconstructive surgeons following surgical resection of the lower gastrointestinal or genitourinary tract. Complication rates and hospital costs are variable and may be linked to the hospital case volume of pelvic reconstructions performed. A comprehensive examination of these factors has yet to be performed.

METHODS

Data were retrieved for patients undergoing pedicled flap reconstruction after pelvic resections in the American National Inpatient Sample database between 2010 and 2014. Patients were then separated into three groups based on hospital case volume for pelvic reconstruction. Multivariate logistic regression and gamma regression with log-link function were used to analyze associations between hospital case volume, surgical outcomes, and cost.

RESULTS

In total, 2,942 patients underwent pelvic flap reconstruction with surgical complications occurring in 1,466 patients (49.8%). Total median cost was $38,469.40. Pelvic reconstructions performed at high-volume hospitals were significantly associated with fewer surgical complications (low: 51.4%, medium: 52.8%, high: 34.8%; p < 0.001) and increased costs (low: $35,645.14, medium: $38,714.92, high: $44,967.29; p < 0.001). After regression adjustment, high hospital volume was the strongest independently associated factor for decreased surgical complications (Exp[β], 0.454; 95% Confidence Interval, 0.346-0.596; p < 0.001) and increased hospital cost (Exp[β], 1.351; 95% Confidence Interval, 1.285-1.421; p < 0.001).

CONCLUSIONS

Patients undergoing pelvic flap reconstruction after oncologic resections experience high complication rates. High case volume hospitals were independently associated with significantly fewer surgical complications but increased hospital costs. Reconstructive surgeons may approach these challenging patients with greater awareness of these associations to improve outcomes and address cost drivers.

En Bloc Capsulectomy for Breast Implant Illness: A Social Media Phenomenon?

BACKGROUND

En bloc capsulectomy has recently increased in prominence as a potential surgical therapy for patients with breast implant illness (BII). However, this procedure has chiefly been recommended for treating breast implant-associated anaplastic large cell lymphoma (BIA-ALCL).

OBJECTIVES

This study aimed to review the current literature and evaluate the public understanding of treatment options for BII via social media to characterize any potential communication disconnect between clinicians and patients.

METHODS

An electronic literature review was performed to identify all available publications mentioning evidence-based support for en bloc capsulectomy as treatment for BII and BIA-ALCL. Twitter social media posts referencing BII or BIA-ALCL were analyzed from 2010 to 2019. Author identity and any mention of surgical treatment were assessed.

RESULTS

A total of 115 publications on the subject of BII and 315 articles on BIA-ALCL were identified. En bloc resection was recommended only for patients with a diagnosis of BIA-ALCL. A total of 6419 tweets referencing BII and 6431 tweets referencing BIA-ALCL were identified. Tweets referencing BIA-ALCL were significantly more likely to be authored by physicians (25.9% vs 5.3%, P < 0.001), and tweets referencing BII were significantly more likely to mention any surgical treatment (7.8% vs 1.9%, P < 0.001) and en bloc capsulectomy (1.4% vs 0.3%, P < 0.001).

CONCLUSIONS

This study demonstrates that a communication disconnect exists between the scientific literature and social media regarding treatment options for BII and BIA-ALCL. Physicians should be aware of these potential misconceptions to empathetically address patient concerns in a patient-centered manner.

Advanced Practice Provider Clinics: Expediting Care For Children Undergoing Tympanostomy Tube Placement

OBJECTIVE/HYPOTHESIS

Advanced practice provider (APP) employment is becoming common in pediatric otolaryngology practices, though few studies have evaluated the consequences that APP-led clinics have on access to care. The objectives of this study were: 1) to investigate whether access to bilateral myringotomy with tympanostomy tube placement (BMT) for recurrent acute otitis media (RAOM) differed between patients seen in otolaryngologist and APP-led clinics 2) to compare clinical characteristics of patients seen by provider type.

METHODS

Retrospective cohort study at an academic, tertiary care pediatric otolaryngology practice. All children were <18 years old and underwent evaluation for RAOM followed by BMT. We compared time in days from scheduling pre-operative appointment to appointment date and time from appointment to BMT between patients seen by APPs and otolaryngologists using Mann-Whitney U tests and multivariate linear regression models. We compared clinical characteristics by provider type using Mann-Whitney U tests and Fisher exact tests.

RESULTS

A total of 957 children were included. Children seen by APPs had significantly shorter wait times for appointments (median 19 vs. 39 days, P < .001) and shorter times from preoperative appointment to BMT (median 25 vs. 37 days, P < .001). Patients seen by otolaryngologists had increased prevalence of craniofacial abnormalities, Down Syndrome, hearing loss, history of otologic surgery, and higher ASA physical status classification.

CONCLUSIONS

Children seen by APPs received care more quickly than those seen by otolaryngologists. Patients seen by otolaryngologists tended to be more medically complex. Implementation of independent APP clinics may expedite and improve access to BMT for children with RAOM.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:2133-2140, 2021.

Natural Killer Cell Phenotype and Functionality Affected by Exposure to Extracellular Survivin and Lymphoma-Derived Exosomes

The inherent abilities of natural killer (NK) cells to recognize and kill target cells place them among the first cells with the ability to recognize and destroy infected or transformed cells. Cancer cells, however, have mechanisms by which they can inhibit the surveillance and cytotoxic abilities of NK cells with one believed mechanism for this: their ability to release exosomes. Exosomes are vesicles that are found in abundance in the tumor microenvironment that can modulate intercellular communication and thus enhance tumor malignancy. Recently, our lab has found cancer cell exosomes to contain the inhibitor of apoptosis (IAP) protein survivin to be associated with decreased immune response in lymphocytes and cellular death. The purpose of this study was to explore the effect of survivin and lymphoma-derived survivin-containing exosomes on the immune functions of NK cells. NK cells were obtained from the peripheral blood of healthy donors and treated with pure survivin protein or exosomes from two lymphoma cell lines, DLCL2 and FSCCL. RNA was isolated from NK cell samples for measurement by PCR, and intracellular flow cytometry was used to determine protein expression. Degranulation capacity, cytotoxicity, and natural killer group 2D receptor (NKG2D) levels were also assessed. Lymphoma exosomes were examined for size and protein content. This study established that these lymphoma exosomes contained survivin and FasL but were negative for MHC class I-related chains (MIC)/B (MICA/B) and TGF-β. Treatment with exosomes did not significantly alter NK cell functionality, but extracellular survivin was seen to decrease natural killer group 2D receptor (NKG2D) levels and the intracellular protein levels of perforin, granzyme B, TNF-α, and IFN-γ.

In-vivo efficacy of biodegradable ultrahigh ductility Mg-Li-Zn alloy tracheal stents for pediatric airway obstruction

Pediatric laryngotracheal stenosis is a complex congenital or acquired airway injury that may manifest into a potentially life-threatening airway emergency condition. Depending on the severity of obstruction, treatment often requires a combination of endoscopic techniques, open surgical repair, intraluminal stenting, or tracheostomy. A balloon expandable biodegradable airway stent maintaining patency while safely degrading over time may address the complications and morbidity issues of existing treatments providing a less invasive and more effective management technique. Previous studies have focused on implementation of degradable polymeric scaffolds associated with potentially life-threatening pitfalls. The feasibility of an ultra-high ductility magnesium-alloy based biodegradable airway stents was demonstrated for the first time. The stents were highly corrosion resistant under in vitro flow environments, while safely degrading in vivo without affecting growth of the rabbit airway. The metallic matrix and degradation products were well tolerated by the airway tissue without exhibiting any noticeable local or systemic toxicity.

Mechanical Allodynia Circuitry in the Dorsal Horn Is Defined by the Nature of the Injury

The spinal dorsal horn is a major site for the induction and maintenance of mechanical allodynia, but the circuitry that underlies this clinically important form of pain remains unclear. The studies presented here provide strong evidence that the neural circuits conveying mechanical allodynia in the dorsal horn differ by the nature of the injury. Calretinin (CR) neurons in lamina II inner convey mechanical allodynia induced by inflammatory injuries, while protein kinase C gamma (PKCγ) neurons at the lamina II/III border convey mechanical allodynia induced by neuropathic injuries. Cholecystokinin (CCK) neurons located deeper within the dorsal horn (laminae III-IV) are important for both types of injuries. Interestingly, the Maf⁺ subset of CCK neurons is composed of transient vesicular glutamate transporter 3 (tVGLUT3) neurons, which convey primarily dynamic allodynia. Identification of an etiology-based circuitry for mechanical allodynia in the dorsal horn has important implications for the mechanistic and clinical understanding of this condition.

Comparative Effectiveness of Transversus Abdominis Plane Blocks in Abdominally Based Autologous Breast Reconstruction: A Systematic Review and Meta-analysis

BACKGROUND

The abdomen is the most common donor site in autologous microvascular free flap breast reconstruction and contributes significantly to postoperative pain, resulting in increased opioid use, length of stay, and hospital costs. Enhanced Recovery After Surgery (ERAS) protocols have demonstrated multiple clinical benefits, but these protocols are widely heterogeneous. Transversus abdominis plane (TAP) blocks have been reported to improve pain control and may be a key driver of the benefits seen with ERAS pathways.

METHODS

A systematic review and meta-analysis of studies reporting TAP blocks for abdominally based breast reconstruction were performed. Studies were extracted from 6 public databases before February 2019 and pooled in accordance with the PROSPERO registry. Total opioid use, postoperative pain, length of stay, hospital cost, and complications were analyzed using a random effects model.

RESULTS

The initial search yielded 420 studies, ultimately narrowed to 12 studies representing 1107 total patients. Total hospital length of stay (mean difference, -1.00 days; P < 0.00001; I = 81%) and opioid requirement (mean difference, -133.80 mg of oral morphine equivalent; P < 0.00001; I = 97%) were decreased for patients receiving TAP blocks. Transversus abdominis plane blocks were not associated with any significant differences in postoperative complications (P = 0.66), hospital cost (P = 0.22), and postoperative pain (P = 0.86).

CONCLUSIONS

Optimizing postoperative pain management after abdominally based microsurgical breast reconstruction is invaluable for patient recovery. Transversus abdominis plane blocks are associated with a reduction in length of stay and opioid use, representing a safe and reasonable strategy for decreasing postoperative pain.

A novel vitamin D gene therapy for acute myeloid leukemia

Current treatment approaches for older adult patients with acute myeloid leukemia (AML) are often toxic and lack efficacy. Active vitamin D3 (1,25(OH)₂D3) has been shown to induce myeloid blast differentiation but at concentrations that have resulted in unacceptable, off-target hypercalcemia in clinical trials. In our study, we found that the combination of 1,25(OH)₂D3 and the hypomethylating agent (HMA) 5-Azacytidine (AZA) enhanced cytotoxicity and differentiation, and inhibited proliferation of several AML cell lines (MOLM-14, HL60) and primary AML patient samples. This observation was corroborated by our RNA sequence analysis data in which VDR, CD14, and BAX expression were increased, and FLT-3, PIM1 and Bcl-2 expression were decreased. To address the hypercalcemia issue, we genetically engineered MOLM-14 cells to constantly express CYP27B1 (the VD3 activating enzyme, 1-α-hydroxylase-25(OH)D3) through lentiviral transduction procedures. Subsequently, we used these cells as vehicles to deliver the CYP27B1 enzyme to the bone marrow of AML mice. We observed that AML mice with CYP27B1 treatment had longer overall survival compared to no treatment and displayed no significant change in calcium level.

School-Aged Anthropometric Outcomes After Endoscopic or Open Repair of Metopic Synostosis

BACKGROUND AND OBJECTIVES

Metopic craniosynostosis can be treated by fronto-orbital advancement or endoscopic strip craniectomy with postoperative helmeting. Infants younger than 6 months of age are eligible for the endoscopic repair. One-year postoperative anthropometric outcomes have been shown to be equivalent, with significantly less morbidity after endoscopic treatment. The authors hypothesized that both repairs would yield equivalent anthropometric outcomes at 5-years postoperative.

METHODS

This study was a retrospective chart review of 31 consecutive nonsyndromic patients with isolated metopic craniosynostosis treated with either endoscopic or open correction. The primary anthropometric outcomes were frontal width, interfrontal divergence angle, the Whitaker classification, and the presence of lateral frontal retrusion. Peri-operative variables included estimated blood loss, rates of blood transfusion, length of stay, and operating time.

RESULTS

There was a significantly lower rate of lateral frontal retrusion in the endoscopic group. No statistically significant differences were found in the other 3 anthropometric outcomes at 5-years postoperative. The endoscopic group was younger at the time of surgery and had improved peri-operative outcomes related to operating time, hospital stay and blood loss. Both groups had low complication and reoperation rates.

CONCLUSIONS

In our cohort of school-aged children with isolated metopic craniosynostosis, patients who underwent endoscopic repair had superior or equivalent outcomes on all 4 primary anthropometric measures compared with those who underwent open repair. Endoscopic repair was associated with significantly faster recovery and decreased morbidity. Endoscopic repair should be considered in patients diagnosed with metopic craniosynostosis before 6 months of age.

Plastic Surgery in the Time of COVID-19

BACKGROUND

 The novel coronavirus disease 2019 (COVID-19) has swept the world in the last several months, causing massive disruption to existing social, economic, and health care systems. As with all medical fields, plastic and reconstructive surgery has been profoundly impacted across the entire spectrum of practice from academic medical centers to solo private practice. The decision to preserve vital life-saving equipment and cancel elective procedures to protect patients and medical staff has been extremely challenging on multiple levels. Frequent and inconsistent messaging disseminated by many voices on the national stage often conflicts and serves only to exacerbate an already difficult decision-making process.

METHODS

 A survey of relevant COVID-19 literature is presented, and bioethical principles are utilized to generate guidelines for plastic surgeons in patient care through this pandemic.

RESULTS

 A cohesive framework based upon core bioethical values is presented here to assist plastic surgeons in navigating this rapidly evolving global pandemic.

CONCLUSION

 Plastic surgeons around the world have been affected by COVID-19 and will adapt to continue serving their patients. The lessons learned in this present pandemic will undoubtedly prove useful in future challenges to come.

Faecal carriage of optrA-positive enterococci in asymptomatic healthy humans in Hangzhou, China

OBJECTIVES

To investigate the faecal carriage of optrA-positive enterococci among asymptomatic healthy humans in Hangzhou, China, and to characterize the genetic context of optrA.

METHODS

A total of 3458 stool samples from healthy individuals were collected and cultured on a selective medium containing 10 mg/L florfenicol and resulting enterococci were screened for the presence of optrA by PCR. OptrA variants were determined by amino acid sequence comparison with the original OptrA from Enterococcus faecalis E349. Whole genome sequencing and PCR mapping were performed to obtain and analyse the genetic environment of optrA.

RESULTS

Similar optrA carriage rates (∼3.5%) were detected in samples from adults (55/1558) and children (66/1900). Linezolid resistance rates for E. faecalis, Enterococcus faecium and other Enterococcus species were 58.5% (38/65), 42.3% (11/26) and 0% (0/31), respectively. Nineteen OptrA variants exhibiting different linezolid MICs were identified. Isolates carrying wild-type OptrA and variants RDK, KLDP, KD, D, RDKP, and EDP generally demonstrated linezolid MICs ≥8 mg/L. The OptrA variants, with fexA upstream and erm(A) downstream, were flanked by IS1216E at one or both ends. The fexA-optrA(wild-type) was located downstream of a Tn554 transposon, and was inserted into the radC gene. The EDM variant was detected in 31/73 enterococci with linezolid MICs ≤4 mg/L. Despite the variable genetic context, Tn558-araC-optrA(EDM)-erm(A)-met was the most common gene array.

CONCLUSIONS

This study revealed a correlation between linezolid MIC, genetic context and OptrA variant. Intestinal colonization of healthy individuals by optrA-positive enterococci is a concern, and active epidemiological surveillance of optrA is warranted.

Estrogen-regulated feedback loop limits the efficacy of estrogen receptor-targeted breast cancer therapy

Endocrine therapy resistance invariably develops in advanced estrogen receptor-positive (ER+) breast cancer, but the underlying mechanisms are largely unknown. We have identified C-terminal SRC kinase (CSK) as a critical node in a previously unappreciated negative feedback loop that limits the efficacy of current ER-targeted therapies. Estrogen directly drives CSK expression in ER+ breast cancer. At low CSK levels, as is the case in patients with ER+ breast cancer resistant to endocrine therapy and with the poorest outcomes, the p21 protein-activated kinase 2 (PAK2) becomes activated and drives estrogen-independent growth. PAK2 overexpression is also associated with endocrine therapy resistance and worse clinical outcome, and the combination of a PAK2 inhibitor with an ER antagonist synergistically suppressed breast tumor growth. Clinical approaches to endocrine therapy-resistant breast cancer must overcome the loss of this estrogen-induced negative feedback loop that normally constrains the growth of ER+ tumors.

Drivers of Hospital Costs in the Self-Pay Facelift (Rhytidectomy) Patient: Analysis of Hospital Resource Utilization in 1890 Patients

INTRODUCTION

Rhytidectomy is one of the most commonly performed cosmetic procedures by plastic surgeons. Increasing attention to the development of a high-value, low-cost healthcare system is a priority in the USA. This study aims to analyze specific patient and hospital factors affecting the cost of this procedure.

METHODS

We conducted a retrospective cohort study of self-pay patients over the age of 18 who underwent rhytidectomy using the Healthcare Utilization Cost Project National Inpatient Sample database between 2013 and 2014. Mean marginal cost increases patient characteristics, and outcomes were studied. Generalized linear modeling with gamma regression and a log-link function were performed along with estimated marginal means to provide cost estimates.

RESULTS

A total of 1890 self-pay patients underwent rhytidectomy. Median cost was $11,767 with an interquartile range of $8907 [$6976-$15,883]. The largest marginal cost increases were associated with postoperative hematoma ($12,651; CI $8181-$17,120), West coast region ($7539; 95% CI $6412-$8666), and combined rhinoplasty ($7824; 95% CI $3808-$11,840). The two risk factors associated with the generation of highest marginal inpatient costs were smoking ($4147; 95% CI $2804-$5490) and diabetes mellitus ($5622; 95% CI $3233-8011). High-volume hospitals had a decreased cost of - $1331 (95% CI - $2032 to - $631).

CONCLUSION

Cost variation for inpatient rhytidectomy procedures is dependent on preoperative risk factors (diabetes and smoking), postoperative complications (hematoma), and regional trends (West region). Rhytidectomy surgery is highly centralized and increasing hospital volume significantly decreases costs. Clinicians and hospitals can use this information to discuss the drivers of cost in patients undergoing rhytidectomy.

LEVEL OF EVIDENCE V

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

CDK12 Inhibition Reverses De Novo and Acquired PARP Inhibitor Resistance in BRCA Wild-Type and Mutated Models of Triple-Negative Breast Cancer

Although poly(ADP-ribose) polymerase (PARP) inhibitors are active in homologous recombination (HR)-deficient cancers, their utility is limited by acquired resistance after restoration of HR. Here, we report that dinaciclib, an inhibitor of cyclin-dependent kinases (CDKs) 1, 2, 5, and 9, additionally has potent activity against CDK12, a transcriptional regulator of HR. In BRCA-mutated triple-negative breast cancer (TNBC) cells and patient-derived xenografts (PDXs), dinaciclib ablates restored HR and reverses PARP inhibitor resistance. Additionally, we show that de novo resistance to PARP inhibition in BRCA1-mutated cell lines and a PDX derived from a PARP-inhibitor-naive BRCA1 carrier is mediated by residual HR and is reversed by CDK12 inhibition. Finally, dinaciclib augments the degree of response in a PARP-inhibitor-sensitive model, converting tumor growth inhibition to durable regression. These results highlight the significance of HR disruption as a therapeutic strategy and support the broad use of combined CDK12 and PARP inhibition in TNBC.

Utility of intraoperative and postoperative radiographs in pediatric cochlear implant surgery

OBJECTIVE

Routine plain film radiographs are often obtained to confirm proper placement of electrode after pediatric cochlear implant surgery. Objective is to evaluate necessity of routine radiographs in pediatric cochlear implant cases.

STUDY DESIGN

Retrospective review.

SETTING

Two tertiary care academic centers.

SUBJECTS AND METHODS

Review of all children that underwent cochlear implantation from January 2003 thru June 2015. Exclusions include patients without intraoperative evoked compound action potential (ECAP) data or radiographs and patients undergoing revision surgeries.

RESULTS

235 pediatric patients underwent 371 cochlear implants. ECAP measurements were not available in two cases and were excluded from study. Radiographs were obtained in 35/369 cases due to intraoperative concern and four had abnormal findings. All four cases underwent change in management. One other patient had an x-ray because of difficult insertion and abnormal ECAP. Radiograph was normal; however, incision was opened and electrodes inserted further. Overall, 5/369 cases had changes in management intraoperatively. In all five cases, abnormalities were suspected by clinician judgment or abnormal ECAP measurements. Routine radiographs were completed in 349/369 cases and one was abnormal. This patient had known partial insertion due to cochlear fibrosis from meningitis and abnormal radiograph did not result in change in management.

CONCLUSION

Clinician suspicion and/or abnormal ECAP prompted suspicion for abnormal electrode placement prior to evaluation with radiograph in all cases in which change in management occurred. Intraoperative radiographs may be valuable in setting of clinical suspicion. Routine radiographs do not result in change in management and are, therefore, unnecessary.

Abstract LB-257: Estrogen signaling in mature luminal and luminal progenitor cells of BRCA2 carriers and non-carriers

Background: Carriers of mutations in the breast cancer susceptibility gene BRCA2 have a 50-80% lifetime risk of developing breast cancers, about 70% of which are positive for estrogen receptor (ER), a key oncogenic hormone receptor. Metastatic ER+ tumors also respond to PARP inhibitors associated with their DNA repair defect. There remains much to understand regarding estrogen signaling in BRCA2 carriers and preventing cancers in this high-risk population.

Methods: We studied the transcriptomes and in-vitro growth of luminal progenitors and mature luminal cells derived from primary human normal breast tissue obtained from BRCA2 carriers and wild-type patients undergoing prophylactic mastectomy and reduction mammoplasty procedures, respectively. Subsequently, formalin-fixed paraffin-embedded breast cancer tissue samples from twelve case-control matched pairs of BRCA2 carriers and wild-type patients were investigated for ER genomic binding, H3K27Ac enhancer marks, and gene expression changes.

Results: Luminal progenitors and mature luminal cells have different gene expression patterns. Unsupervised clustering of transcriptomes from normal tissue of three pairs of BRCA2-mutant and wildtype patients suggested that BRCA2 mutation status can segregate transcriptomes from luminal progenitors but not mature luminal cells. These differential transcriptomes in luminal progenitor cells from BRCA2 carriers were enriched for cell proliferation genes. In agreement, greater proliferative phenotype was observed in BRCA2-mutant luminal progenitor cells in comparison to the wild-type cohort. Interestingly, clustering analyses of twelve pairs of breast tumors indicated no clear differences between ER cistromes, enhancer marks and gene expression between BRCA2 carriers and wildtype patients. Because luminal progenitor cells are more likely to contribute to tumorigenesis, we hypothesize that the identified BRCA2-mutant signature in normal progenitor cells could be retained in tumors obtained from BRCA2 carriers.

Conclusions: There are differential gene expression patterns between luminal progenitors and mature luminal cells obtained from normal human breast tissue. The transcriptomes in the luminal progenitor but not mature luminal cells segregate differently based on the BRCA2 mutation status. This identified BRCA2-mutant gene signature in luminal progenitor cells is enriched for pro-proliferation pathways, and BRCA2-mutant luminal progenitor cells exhibit higher cell proliferation, suggesting a potential cell-of-origin in BRCA2-associated breast cancers. Importantly, no significant differences in transcriptomes and ER cistromes are observed in breast tumors from BRCA2 carriers and non-carriers, indicating a need to identify BRCA2-mutant gene signature that may assist in segregating ER+ breast cancers in this high-risk populations. The knowledge from this study may assist in pioneering strategies for cancer prevention in high-risk BRCA2 mutation carriers.

Citation Format: Hari Singhal, David Chi, Elgene Lim, Housheng He, Raga Vadhi, Prakash K. Rao, Henry W. Long, Andrea L. Richardson, Judy Garber, Myles Brown. Estrogen signaling in mature luminal and luminal progenitor cells of BRCA2 carriers and non-carriers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-257. doi:10.1158/1538-7445.AM2017-LB-257

Abstract 3376: Reprogramming the estrogen signaling network is a potential mechanism for human breast tumorigenesis

Background: The estrogen receptor (ER) is expressed in approximately 70% of sporadic breast cancers and is known to activate genes driving cell proliferation. Much work in the field has characterized the mechanisms of ER signaling behind cancer progression and eventual metastasis, and therapeutic targeting of the ER signaling pathway has proven effective. However, little is known regarding the role of ER in the initial process of transformation. Since ER possesses pro-differentiation roles in normal breast development yet becomes one of the drivers of breast cancer, altered ER function is then likely a crucial early step. We seek to investigate the role of ER from the perspective of the normal breast to allow for mechanistic insights into breast tumorigenesis.

Methods: To model the normal breast epithelium, viable tissue specimens from patients undergoing reduction mammoplasty were obtained and enriched for breast epithelial cells via fluorescence-activated cell sorting (FACS). Fresh-frozen ER+ breast tumor samples were then obtained for comparison. RNA-seq, ChIP-seq for ER, and genome-wide CRISPR screening in the presence of estrogen stimulation in both normal breast and breast tumor were performed. These various modalities of genomic data were then integrated and analyzed to identify patterns in breast tumorigenesis.

Results: Gene expression profiling via RNA-seq of breast epithelial cells from seven reduction mammoplasties reveals a drastically different and muted normal response to estrogen stimulation. Genes that promote cell cycling and cell proliferation were down-regulated in normal breast but were up-regulated in breast cancer cells. Furthermore, differential ER binding alone via ER ChIP-seq is capable of segregating ten primary breast tumors from seven normal breast tissues with very few overlapping sites. Deeper motif analysis reveals the enrichment of novel transcription cofactor GRHL2 in the binding sites most closely associated to ER+ breast cancer. Further findings via genome-wide CRISPR screens reveal GRHL2 as an essential gene in luminal ER+ breast cancer with predictive ability in cancer risk and prognosis.

Conclusions: Cellular reprogramming of the ER signaling network may alter the functioning phenotype of normal mammary epithelial cells and offer insights into the series of events necessary for developing breast cancer. Notably, ER activation does not promote cellular proliferation in normal mammary epithelial cells, and the interaction with transcriptional cofactors such as GRHL2 can be a driving mechanism for breast tumorigenesis. Unraveling the differential ER signaling in normal mammary epithelium and breast cancer will enhance our understanding of breast cancer and aid the development of more effective prevention strategies and targeted therapeutics.

Citation Format: David Chi, Hari Singhal, Lewyn Li, Henry W. Long, Judy E. Garber, Myles A. Brown. Reprogramming the estrogen signaling network is a potential mechanism for human breast tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3376. doi:10.1158/1538-7445.AM2017-3376

The influence of delipidation on triglyceride and LIPIN1 of porcine embryos derived from parthenogenetic activation

Proteins in the LIPIN family play key roles in lipid synthesis mainly on triacylglycerol (TAG) biosynthesis, and they also act as transcriptional coactivators to regulate the expression of genes involved in lipid metabolism with other nuclear factors. Hence, this study was designed to investigate LIPIN1 in pig oocytes and embryos by the delipidation. After delipidation, the content of lipids (LDs) and TAG in MII oocyte was significantly reduced; however, a similar increasing tendency of TAG was shown during embryos development. Subsequently, the expression of genes related to TAG biosynthesis including GPAT1, AGPAT1, AGPAT2, LIPIN1, DGAT and the nuclear factors interacted with LIPIN1 including PPARα and PPARγ was investigated. It is obvious that DGAT and GPAT1, and LIPIN1 increased significantly after delipidation at 1-cell and 4-cell stage, and the expression of PPARα and PPARγ also increased at 4-cell stage. By immunofluorescence staining and Western blots, LIPIN1 was found to exhibit a dynamic localization pattern and gradually increase with the development of delipated embryo. In the early developmental stages (1-, 2- and 4-cell stages), it was distributed over the cortical layer. But at the blastocyst stage, a homogeneous distribution of LIPIN1 was observed in cytoplasm. At 2-cell stage, the expression of PPARα decreased when LIPIN1 was interfered by small interfering RNA, but PPARγ has no significant difference. Therefore, in this study, we find after delipidation, the content of TAG and LIPIN1 will gradually increase during embryo development and nuclear factor PPARα and PPARγ can also be affected by delipidation. The interaction of LIPIN1 and PPARα exists in porcine embryo.

[Not Available]

A cross was made of Elymus repens onto the wheat cultivar Crocus and BC1 progeny advanced to BC1F7 by single seed descent. Sixteen lines were selected based on agronomic performance and evaluated in an FHB epiphytotic nursery. Eight lines with FHB resistance were selected. Based on GISH analysis, line P1142-3-1-5 had 42 chromosomes with one pair of chromosomes showing telomeric translocations on both arms. This chromosome was identified as 3D by using SSR markers. An evaluation of lines with single translocations revealed that FHB resistance was contributed by the translocation on the long arm of chromosome 3D. That line has minimal linkage drag and should be amenable to applications in breeding for disease resistance.

Abstract P4-21-37: Phase I trial of ruxolitinib in combination with trastuzumab in metastatic HER2 positive breast cancer

Background

Preclinical and clinical studies suggest that trastuzumab resistance in HER2 amplified breast cancer (HER2+ BC) is mediated by cross-activation of alternative signaling pathways. Computational analysis and pooled whole-genome RNAi screens in HER2 transformed BC cell lines identified the IL6/JAK2/STAT3 axis as a master regulator pathway. The combination of trastuzumab plus ruxolitinib, a JAK1/JAK2 inhibitor, demonstrated synergistic tumor growth inhibition in mouse xenografts of HER2 transformed BC cell lines. These data provide the rationale for studying the efficacy of ruxolitinib and trastuzumab in a clinical trial.

Design

This is a multi-center, open-label, phase I/II trial of ruxolitinib plus trastuzumab in patients (pts) with HER2+ metastatic BC (MBC) who have progressed on &gt;2 HER2-directed therapies in the metastatic setting (including trastuzumab, pertuzumab and T-DM1). The phase I is an adaptive design with 10 pts, using the time-to-event continual reassessment method to determine the recommended phase II dose. Phase II will be a non-randomized, open-label trial with 30 evaluable pts. The duration of a treatment cycle is 21 days, with trastuzumab given on Day 1 and ruxolitinib taken orally twice daily continuously. The primary endpoint of phase I is to determine the maximum tolerated dose of the drug combination. The phase I dose range for ruxolitinib is 10-25 mg BID (dose level 0: 20 mg BID). Response is assessed by imaging every 9 weeks. Blood samples and optional tissue biopsies are obtained for biomarker analysis at the following time points: pre-treatment, on-treatment C2D1, and at progression.

Results

Phase I started accrual in the fall of 2014. The trial has accrued 12 patients, with 9 evaluable and 3 non-evaluable patients. Of the evaluable patients, the mean age was 55.9 (range 32-69). Of these, 7 were postmenopausal (78%) 5/9 (56%) were estrogen receptor positive, and all had measurable disease. The mean number of prior lines of therapy in the metastatic setting was 5.6 (range: 3-8), including a mean of 3.2 (range: 2-5) prior regimens containing HER2 targeted therapies. As of 6/12/16, 2 patients remain on therapy. As this is an adaptive design, efficacy and drug tolerability will not be mentioned in this abstract to not bias the ongoing analysis. However, we anticipate that by SABCS 2016, 10 evaluable patients will have completed the DLT period – at which point, complete data will be presented.

Conclusion

Ruxolitinib plus trastuzumab is a novel, non-chemotherapy containing regimen. The phase I analysis is ongoing. We plan on reporting full safety/tolerability and efficacy data once 10 evaluable patients have completed the phase I (9/10 have currently completed DLT period). Given an early signal in HER2+ breast cancer, in this heavily pretreated population we will proceed directly to a phase II trial with the combination.

Citation Format: Mundi PS, Lee S, Chi D, Bhardwaj A, Makower D, Cigler T, Crew KD, Hershman DL, Califano A, Silva J, Kalinsky KM. Phase I trial of ruxolitinib in combination with trastuzumab in metastatic HER2 positive breast cancer [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 P4-21-37.

Abstract A03: Effects of survivin and lymphoma cell-derived exosomes on natural killer cell function

Tumors alter their microenvironment to promote survival using methods such as angiogenesis promotion, growth signals, and immune suppression. The immune system, whose regular function is to recognize and eradicate infected or abnormal cells, often seems unresponsive to transformed neoplastic cells. Many of the methods employed by tumors to reduce immune function are unclear, but there is evidence for T cell suppression, increased myeloid-derived suppressor cells (MDSCs), and reduced natural killer (NK) cell activity. NK cells are among the first cells to recognize and destroy abnormal cells due to their inherent killing capabilities. However, many types of cancers inhibit the surveillance and cytotoxic abilities of NK cells by releasing exosomes, vesicles that can modulate tumor microenvironment and intercellular communication for the purpose of enhancing tumor malignancy. Exosomes as a means for immunomodulation of tumor microenvironment have been the focus of recent research. These 50-150 nm sized lipid bound vesicles are secreted by many cell types, including immune cells and tumor cells, and the unique protein, lipid, mRNA and miRNA contents contribute to the complex intercellular communication occurring between malignant and normal cells. Cancer patients often have increased numbers of exosomes circulating through their body, including patients with hematological malignancies, such as lymphoma. Recently, cancer cell exosomes have been found to contain Survivin, an Inhibitor of Apoptosis (IAP) protein that prevents cell death and induces Th2 polarity shift and decreases proliferation and cytotoxicity of CD8+ T lymphocytes. The purpose of this study is to explore the effect of Survivin and cancer cell-derived exosomes, which contain Survivin, on the immune functions of NK cells. The hypothesis is that Survivin and exosomes will decrease NK cell functions by suppressing NK cell production or release of cytokines and cytotoxic granules. NK cells were obtained from peripheral blood using magnetic NK cell isolation kit from Miltenyi Biotec and exosomes were obtained from conditioned media from two lymphoma cell lines (WSU-DLCL2 and WSU-FSCCL) using ExoQuickTM (System Biosciences). Flow cytometry methods were used to evaluate degranulation capacity by measuring levels of CD107a, as well as expression of activating receptor NKG2D, cytotoxic granules (perforin, Granzyme B) and cytokines (TNF-α, IFN-γ). RNA message expression was investigated using both block RT-PCR and qPCR. Results showed little significant difference in ability to degranulate when exposed to stimuli, and NKG2D levels did not change after exposure to Survivin or lymphoma exosomes. Although ImageJ analysis of block PCR showed some instances of decreased band densities in some donors treated with Survivin protein, RNA levels in general did not show a trend between NK donors in response to treatment. However, protein expression of Granzyme B, perforin, TNF-α, and IFN-γ did appear to decrease after Survivin treatment. This work is still in the early stages and results are inconsistent due to donor variability. More samples are required, as well as further studies on NK cell functional cytotoxicity.

Citation Format: Heather R. Ferguson Bennit, Amber Gonda, Jenniffer Licero Campbell, Laura Oppegard, David Chi, Nathan R. Wall. Effects of survivin and lymphoma cell-derived exosomes on natural killer cell function. [abstract]. In: Proceedings of the AACR Special Conference: Function of Tumor Microenvironment in Cancer Progression; 2016 Jan 7–10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2016;76(15 Suppl):Abstract nr A03.

Abstract 3941: Novel biomarkers and multiplexed NGS to stratify FFPE NSCLC by tumor infiltrating lymphocytes and histopathology phenotypes

There is increasing evidence supporting the association of tumor infiltrating lymphocytes (TIL) and drug sensitivity of solid tumors. In particular, primary and meta-analyses have reported a positive correlation between TIL level and outcome in advanced non-small cell lung cancer (NSCLC) treated with checkpoint inhibitors such as PD-1 and PD-L1. Recent trials with immunotherapies have started including TIL assessment in the study protocol in recognition of this metric as a predictive and prognostic biomarker. TIL levels are typically quantified by visual assessment of H&E-stained tumor sections. While this approach is generally accepted as the standard, there is an increased recognition that visual assessment of H&E-stained slides lacks precision and is relatively subjective (Salgado R, 2015; Schalper KA, 2015). Furthermore, as investigators are often also interested in measurements of additional biomarkers such as IFNg as well as the drug targets, a gene panel approach offers a convenient solution to objectively quantify expression levels of these informative markers. Here we report the discovery and verification of a unique gene expression signature that is capable of stratifying FFPE samples of NSCLC tumors by TIL levels and histopathology phenotypes (adenocarcinoma vs. squamous cell carcinoma). Gene expression was measured by an RNA Ion AmpliSeq Gene Expression research panel* containing 200 assays. Each research sample was measured with replicates at library generation step and sequencing step. Technical replicates were found to have &gt;0.99 correlation among each other. Assays on the panels were also found to be robust with respect to low input amount (1-10 ng RNA). *For Research Use Only. Not for use in diagnostic procedures.

Citation Format: Ann Mongan, Sophie Rozenzhak, Geoffrey Bien, David Chi, Hiroyoshi Nishikawa, Fiona Hyland, Jim Godsey. Novel biomarkers and multiplexed NGS to stratify FFPE NSCLC by tumor infiltrating lymphocytes and histopathology phenotypes. [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 3941.

Abstract 1386: Clinical research results for a NGS-based kit for targeted detection of clinically relevant gene rearrangements in lung tumor samples

In recent years, advances in next-generation sequencing (NGS) technologies have enabled faster and cheaper methods for uncovering the genetic basis of disease. For cancer, NGS based screening for known tumor subtypes may inform diagnosis and allow the clinician to tailor a specific therapeutic approach in the future. Here, we present the testing results of one such NGS based kit used to detect specific chromosomal translocations in retrospective non-small cell lung cancer (NSCLC) samples by targeting specific breakpoints in known fusion transcripts.

The included panel tested consists of a single primer pool containing amplicon designs to simultaneously screen for over 75 specific rearrangements involving the receptor tyrosine kinase (RTK) genes ALK, RET and ROS1 as well as NTRK1. The panel was compatible with formalin-fixed paraffin-embedded (FFPE) lung tumor research samples and achieved high-sensitivity down to 10 ng of RNA input. In addition, amplicon assays designed at the 5’ and 3’ ends the RTK genes provide non-specific evidence that a translocation exists in a sample by comparing expression imbalance between the two ends.

Testing was carried out at three external clinical research laboratories. In addition to positive and negative control samples, each site contributed FFPE lung tumor research samples for which ALK fusion status was known prior to NGS library preparation carried out using the Ion AmpliSeq™ workflow. For site-specific samples (n = 144, 16 samples per sequencing run), high concordance, sensitivity and specificity were measured at 97.2%, 90.5% and 98.4%, respectively.

Citation Format: Jeoffrey J. Schageman, José Luis Costa, Orla Sheils, John E. Glassco, David Chi, Jon Sherlock, John Bishop, Rosella P. Petraroli, Kelli S. Bramlett. Clinical research results for a NGS-based kit for targeted detection of clinically relevant gene rearrangements in lung tumor samples. [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 1386.

Influence of Delipation on the Energy Metabolism in Pig Parthenogenetically Activated Embryos

This study was designed not only to measure the effect of delipation on the developmental viability of pig parthenogenetically activated (PA) embryos, but also to evaluate the changes of mitochondria DNA (mtDNA), reactive oxygen species (ROS) level, adenosine triphosphate (ATP) content and gene (Acsl3, Acadsb, Acaa2, Glut1) expression level at different stages after delipation. Results showed that no effect was observed on the cleavage ability, but significant lower blastocyst rate was obtained in delipated embryos. Copy number of mtDNA decreased gradually from MII to four-cell stages and subsequently kept consistent with blastocyst stage both in delipated and control embryos, but the copy number of mtDNA in delipated embryos was similar to that in the control groups no matter at which developmental stage was observed. Both in delipated and control embryos, ATP content progressive decreased from one-cell to blastocyst stages, while just at one-cell stage, a significant decrease of ATP level was observed in delipated embryos compared with that of control. The level of ROS increased obviously after delipation at cleavage stage, but no difference was seen at blastocyst stage. Finally, the expression level of genes related to fatty acids beta-oxidation (Acadsb and Acaa2) was decreased, while the expression level of genes related to glucose metabolism (Glut 1) was upregulated after delipation. In conclusion, the reduction of lipids in pig oocytes will affect the developmental competence of pig PA embryos by disturbed energy metabolism and ROS stress.