Citations

Implantable devices to measure neurochemical or electrical activity from the brain are mainstays of neuroscience research and have become increasingly utilized as enabling components of clinical therapies. In order to increase the number of recording channels on these devices while minimizing the immune response, flexible electrodes under 10 µm in diameter have been proposed as ideal next-generation neural interfaces. However, the representation of motion artifact during neurochemical or electrophysiological recordings using ultra-small, flexible electrodes remains unexplored. In this short communication, we characterize motion artifact generated by the movement of 7 µm diameter carbon fiber electrodes during electrophysiological recordings and fast-scan cyclic voltammetry (FSCV) measurements of electroactive neurochemicals. Through in vitro and in vivo experiments, we demonstrate that artifact induced by motion can be problematic to distinguish from the characteristic signals associated with recorded action potentials or neurochemical measurements. These results underscore that new electrode materials and recording paradigms can alter the representation of common sources of artifact in vivo and therefore must be carefully characterized.

TPS4135 Background: Gastric cancer is a prevalent and morbid illness for which new treatment strategies are needed. Peri-operative therapy is a standard approach that is associated with only a 15% improvement in overall survival. Early FDG-PET scanning, performed prior to cycle 2, can distinguish patients (pts) responding to chemotherapy from those who are not. FDG-PET non-responding pts have poorer survival. This study addresses the question of salvage therapy in pts who are PET non-responders. Specifically, does salvage chemotherapy with docetaxel /irinotecan improve pt survival in FDG-PET-nonresponding pts with locally advanced gastric cancer. Methods: This is a multicenter, cooperative group, NCI supported, randomized phase II study of salvage chemotherapy + surgery versus surgery and post-operative chemoradiotherapy in pts who are FDG-PET non-responders (defined as a decrease in SUVmaxof the primary tumor of less than 35%). A total of 176 pts with locally advanced, resectable gastric cancer who were FDG-PET non-responders to cycle 1 of platinum/capecitabine based chemotherapy will be randomized in a 1:1 manner to receive either (Arm A) surgery followed by fluoropyrimidine-sensitized radiotherapy (4500 cGy), or (Arm B) salvage chemotherapy with docetaxel / irinotecan (DI) for 2 cycles followed by standard resection and 3 cycles DI post-operatively. DI is administered as D 30 mg/m2, I 50 mg/m2 given on D1, D8 of a 21 day cycle. 416 pts will be screened to yield 162 non-responders (81 FDG-PET non-responders per treatment group). With expected 120 events, the study will have 80% power to detect a hazard ratio of 0.625 for improved survival at the one-sided significant level of 0.15. Pts will be required to provide tissue at the time of resection, as well as whole blood prior to resection for correlative studies associated with platinum sensitivity, FDG avidity, and prognostic markers. This study is available through all cooperative groups (SWOG, ACRIN/ECOG, Alliance, and NRG) and the National Clinical Trials Network. Enrollment began in November 2015. Support: U10CA180821, U10CA180882; Clinical Trial Information: NCT02485834 .

3612 Background: The RAS/RAF/MEK signal transduction pathway is critical to the development of colorectal cancer, and tumors harboring KRAS, NRAS, and BRAF mutations were shown to be resistant to radiation. Thus, we conducted a phase I study of trametinib, a potent MEK1/2 inhibitor, in combination with CRT in patients with LARC. Methods: Phase I trial for patients with Stage II/III rectal cancers with a 3+3 design, and an expansion cohort of 12 patients at the maximum tolerated dose (MTD). Trametinib is given orally at 3 dose levels: 0.5mg, 1mg, and 2mg (Mon-Fri). CRT regimen is infusional 5-flourouracil (5FU) 225mg/m2/day (Mon-Fri) and daily fractions of 1.8 Gy (total 50.4Gy). There is a 5-day trametinib lead-in followed by trametinib and CRT. Six to 10 weeks after completion of CRT, patients then proceed to their surgery and adjuvant therapy. The primary endpoint is to identify the MTD and recommended phase 2 dose of trametinib with CRT. Immunohistochemistry staining for phosphorylated –ERK (pERK) and genomic profiling is performed on the tumor samples. Results: Enrollment is complete at all dose levels with18 patients, and 15 patients evaluable for toxicity and response as of Feb 6. One dose-limiting toxicity of diarrhea was observed at the 2mg dose. Grade 3 and most common toxicities are shown in Table 1. No grade 4/5 toxicities have been observed. At 2mg dose level, 3/9 (33%) patients had pathological complete response (pCR) and 2/9 (22%) had a near pCR. Correlative studies confirm decrease in pERK levels with increasing doses of trametinib. Correlation of genomic mutational status with toxicity, response, and outcomes is being analyzed. Conclusions: The combination of trametinib with 5FU CRT is tolerable with promising preliminary activity. Final results will be presented at the meeting. Toxicities. Clinical trial information: NCT01740648. [Table: see text]

ObjectivesDevelop multidisciplinary and international consensus on patient, disease, procedural, and perioperative factors, as well as key outcome measures and complications, to be reported for pediatric airway reconstruction studies.MethodsStandard Delphi methods were applied. Participants proposed items in three categories: 1) patient/disease characteristics, 2) procedural/intraoperative/perioperative factors, and 3) outcome measures and complications. Both general and anatomic site‐specific measures were elicited. Participants also suggested specific operations to be encompassed by this project. We then used iterative ranking and review to develop consensus lists via a priori Delphi consensus criteria.ResultsThirty‐three pediatric airway experts from eight countries in North and South America, Europe, and Australia participated, representing otolaryngology (including International Pediatric Otolaryngology Group members), pulmonology, general surgery, and cardiothoracic surgery. Consensus led to inclusion of 19 operations comprising open expansion, resection, and slide procedures of the larynx, trachea, and bronchi as well as three endoscopic procedures. Consensus was achieved on multiple patient/comorbidity (10), disease/stenosis (7), perioperative‐/intraoperative‐/procedure‐related (16) factors. Consensus was reached on multiple outcome and complication measures, both general and site‐specific (8 general, 13 supraglottic, 15 glottic, 17 subglottic, 8 cervical tracheal, 12 thoracic tracheal). The group was able to clarify how each outcome should be measured, with specific instruments defined where applicable.ConclusionThis consensus statement provides a framework to communicate results consistently and reproducibly, facilitating meta‐analyses, quality improvement, transfer of information, and surgeon self‐assessment. It also clarifies expert opinion on which patient, disease, procedural, and outcome measures may be important to consider in any pediatric airway reconstruction patient.Level of Evidence5 Laryngoscope, 129:244–255, 2019

There is increasing scrutiny from healthcare organizations towards the utility and associated costs of imaging. MRI has traditionally been used as a high‐end modality, and although shown extremely important for many types of clinical scenarios, it has been suggested as too expensive by some. This editorial will try and explain how value should be addressed and gives some insights and practical examples of how value of MRI can be increased. It requires a global effort to increase accessibility, value for money, and impact on patient management. We hope this editorial sheds some light and gives some indications of where the field may wish to address some of its research to proactively demonstrate the value of MRI.Level of Evidence: 5Technical Efficacy: Stage 5J. Magn. Reson. Imaging 2019;49:e14–e25.

New integrated PET‐MRI systems potentially provide a complete imaging modality for diagnosis and evaluation of musculoskeletal disease. MRI is able to provide excellent high‐resolution morphologic information with multiple contrast mechanisms that has made it the imaging modality of choice in evaluation of many musculoskeletal disorders. PET offers incomparable abilities to provide quantitative information about molecular and physiologic changes that often precede structural and biochemical changes. In combination, hybrid PET‐MRI can enhance imaging of musculoskeletal disorders through early detection of disease as well as improved diagnostic sensitivity and specificity. The purpose of this article is to review emerging applications of PET‐MRI in musculoskeletal disease. Both clinical applications of malignant musculoskeletal disease as well as new opportunities to incorporate the molecular capabilities of nuclear imaging into studies of nononcologic musculoskeletal disease are discussed. Lastly, we discuss some of the technical considerations and challenges of PET‐MRI as they specifically relate to musculoskeletal disease.Level of Evidence5Technical EfficacyStage 3 J. Magn. Reson. Imaging 2018;48:27–47.

AbstractBackgroundOncologic outcomes of human papillomavirus (HPV)‐related oropharyngeal squamous cell carcinoma (SCC) requiring resection of major muscular or neurovascular tissue during neck dissection for invasive nodal disease remain uncertain.MethodsPatients with HPV‐related oropharyngeal SCC requiring resection of major muscular or neurovascular tissue during their neck dissections were retrospectively identified.ResultsSeventy‐two patients were included. Regional and distant recurrences occurred in 6% and 17% of patients. Advanced T classification, pathological node number of 5 or more, and omission of adjuvant therapy were associated with decreased disease‐free survival (DFS). The addition of adjuvant chemotherapy was not associated with improved survival.ConclusionPatients with invasive nodal disease from HPV‐related oropharyngeal SCC can be managed with up‐front surgery and adjuvant therapy, as indicated with good regional control. Although distant recurrence was the primary site of failure, adjuvant chemotherapy was not associated with improved outcomes. The T classification, node number, and adjuvant radiotherapy are independent prognostic factors in this patient population.

Protection against the effects of headward acceleration afforded by immersion in water has been assayed in the human centrifuge on 15 trained subjects. Immersion in water to the xyphoid afforded an average protection of 1.1 ± 0.1 G for vision and ear opacity and of 1.6 ± 0.2 G for ear pulse and heart rate. Deeper immersion, to the level of the third rib at the sternum increased the protection to 1.8 ± 0.1 G for vision and ear opacity and to 2.8 ± 0.2 G for ear pulse and heart rate. The protection afforded the various physiologic variables increased with the magnitude of acceleration tested. Protection against loss of consciousness may be greater than protection against blackout and is probably similar to the protection afforded the ear pulse and heart rate. The cardiovascular reactions produced by headward acceleration are qualitatively similar with and without water immersion. This finding does not support the concept that impediment to venous return is the primary determinant of man's tolerance to headward acceleration. Visual symptoms occurred at greater amplitudes of ear pulse, and presumably also at greater blood pressures at head level, during water immersion than during control runs. vision; arterial pressure; heart rate; venous return; arterial pulse in ear Submitted on May 13, 1963