Faculty Bibliography

Liquid biopsy has emerged as a novel noninvasive tool in cancer diagnostics. While significant strides have been made in other malignancies using liquid biopsy for diagnosis, disease monitoring, and treatment selection, development of these assays has been more challenging for brain tumors. Recently, research in primary and metastatic brain tumors has begun to harness the potential utility of liquid biopsy-particularly using circulating tumor DNA (ctDNA). Initial studies to identify ctDNA in plasma of brain tumor patients have shown feasibility, but the yield of ctDNA is far below that for other malignancies. Attention has therefore turned to the cerebrospinal fluid (CSF) as a more robust source of ctDNA. This review discusses the unique considerations in liquid biopsy for glioma and places them in the context of the work to date. We address the utility of CSF liquid biopsy for diagnosis, longitudinal monitoring, tracking tumor evolution, clinical trial eligibility, and prognostication. We discuss the differences in assay requirements for each clinical application to best optimize factors such as efficacy, cost, and speed. Ultimately, CSF liquid biopsy has the potential to transform how we manage primary brain tumor patients.

Endoscopic high-speed video (HSV) systems for visualization and assessment of vocal fold dynamics in the larynx are diverse and technically advancing. To consider resulting "concepts shifts" for neural network (NN)-based image processing, re-training of already trained and used NNs is necessary to allow for sufficiently accurate image processing for new recording modalities. We propose and discuss several re-training approaches for convolutional neural networks (CNN) being used for HSV image segmentation. Our baseline CNN was trained on the BAGLS data set (58,750 images). The new BAGLS-RT data set consists of additional 21,050 images from previously unused HSV systems, light sources, and different spatial resolutions. Results showed that increasing data diversity by means of preprocessing already improves the segmentation accuracy (mIoU + 6.35%). Subsequent re-training further increases segmentation performance (mIoU + 2.81%). For re-training, finetuning with dynamic knowledge distillation showed the most promising results. Data variety for training and additional re-training is a helpful tool to boost HSV image segmentation quality. However, when performing re-training, the phenomenon of catastrophic forgetting should be kept in mind, i.e., adaption to new data while forgetting already learned knowledge.

BACKGROUND:Safe sampling of central nervous system tumor tissue for diagnostic purposes may be difficult if not impossible, especially in pediatric patients, and an unmet need exists to develop less invasive diagnostic tests. METHODS:We report our clinical experience with minimally invasive molecular diagnostics using a clinically validated assay for sequencing of cerebrospinal fluid (CSF) cell-free DNA (cfDNA). All CSF samples were collected as part of clinical care, and results reported to both clinicians and patients/families. RESULTS:We analyzed 64 CSF samples from 45 pediatric, adolescent and young adult (AYA) patients (pediatric = 25; AYA = 20) with primary and recurrent brain tumors across 12 histopathological subtypes including high-grade glioma (n = 10), medulloblastoma (n = 10), pineoblastoma (n = 5), low-grade glioma (n = 4), diffuse leptomeningeal glioneuronal tumor (DLGNT) (n = 4), retinoblastoma (n = 4), ependymoma (n = 3), and other (n = 5). Somatic alterations were detected in 30/64 samples (46.9%) and in at least one sample per unique patient in 21/45 patients (46.6%). CSF cfDNA positivity was strongly associated with the presence of disseminated disease at the time of collection (81.5% of samples from patients with disseminated disease were positive). No association was seen between CSF cfDNA positivity and the timing of CSF collection during the patient's disease course. CONCLUSIONS:We identified three general categories where CSF cfDNA testing provided additional relevant diagnostic, prognostic, and/or therapeutic information, impacting clinical assessment and decision making: (1) diagnosis and/or identification of actionable alterations; (2) monitor response to therapy; and (3) tracking tumor evolution. Our findings support broader implementation of clinical CSF cfDNA testing in this population to improve care.

BACKGROUND:Addressing operational inefficiencies in operating rooms (ORs) enhances patient access to care, reduces delays, and improves employee and patient satisfaction. The Comprehensive Unit-based Safety Program (CUSP) promotes patient safety through increased teamwork, empowerment of frontline staff, and utilization of science of safety principles. CUSP has demonstrated success in outpatient and inpatient settings to decrease complication rates and establish a culture of safety but has been used minimally in the perioperative setting. In this study, the CUSP methodology was utilized to improve perioperative efficiency in pediatric spine surgery, and preimplementation and postimplementation efficiency were compared, using the rate of first case on-time starts (FCOTS) as the primary metric. METHODS:A CUSP quality improvement workgroup including nurses, technicians, surgeons, anesthesiologists, and administrators sought feedback on opportunities for improvement and tracked key performance metrics in the OR from 2015 to 2020. Key interventions developed in response to feedback included standardizing and streamlining room setup and adjusting staffing models for greater efficiency. Univariate analysis was conducted to compare time periods pre-CUSP and post-CUSP implementation. RESULTS:First case on-time starts increased from 38% to a high of 81% after implementation. For more complex cases, the average patient in the room to anesthesia ready time improved by 31% with decreased variance over time, and average closure to patient out of room time improved by 45%. Improvements were sustained through Year 3, while CUSP remained a primary focus for the team. CONCLUSIONS:CUSP is effective in enhancing perioperative efficiency, demonstrating strong improvement in on-time starts over 5 years. The results indicate that process improvement in ORs requires consistent attention to sustain gains over time. Engaging frontline staff in quality improvement fosters collaboration and provides employee buy-in to promoting a culture of safety and improving value in patient care. LEVEL OF EVIDENCE/METHODS:Level III-retrospective comparative study.

We report a case of isolated laryngeal mucormycosis in a patient who presented in diabetic ketoacidosis (DKA). The patient was managed with antifungal therapy and eventual total laryngectomy. To our knowledge, this is the first case presented of mucormycosis with isolated laryngeal involvement.

OBJECTIVES/OBJECTIVE:) laser or microlaryngeal instruments (cold steel). This study compares the functional efficacy and safety of coblation, or "cold" radiofrequency ablation, to traditional approaches for endoscopic laryngeal cleft repair. METHODS:laser, cold steel, or coblator at two tertiary academic centers from 2015 to 2021 were retrospectively identified. The primary outcome studied was swallowing function: pre- and postoperative swallow studies were scored according to the International Dysphagia Diet Standardization Initiative with higher scores indicating worse swallow function. Secondary outcomes included surgical complications and rates of dehiscence. RESULTS:laser, 23 with cold steel, and 16 with the coblator. Mean age at surgery was 2.2 ± 1.1 years for the laser group, 4.3 ± 4.0 years for cold steel, and 1.9 ± 1.4 years for the coblator group. In the laser group, 100% of clefts were type I; for the cold steel group, 82.6% of clefts were type I and 17.4% were type II; for the coblator group, 93.8% of clefts were type I and 6.3% were type II. Pre- and postoperative swallow study scores were 6.3 ± 2.8 and 4.3 ± 3.2, respectively, (p = 0.001) for the laser group, 6.9 ± 2.8 and 5.3 ± 3.1 (p = 0.071) for the cold steel group, and 7.5 ± 1.5 and 4.0 ± 2.9 (p < 0.001) for the coblator group. Mean change in swallow study scores were similar across the three groups (p = 0.212). No patients experienced postoperative dehiscence at the surgical site or complications; no revisions were required. CONCLUSIONS:Cleft repair with the novel coblation technique showed significant improvements in swallow study scores without any occurrences of postoperative dehiscence or revisions. Coblation is a safe and efficacious approach for laryngeal cleft repair.

Introduction: Thyroid fine-needle aspiration (FNA) cytology combined with molecular testing guides individualized patient management by providing information regarding tumor biology and the risk of recurrence associated with specific mutations in the indeterminate groups (Bethesda group III-V). Thyroid adenomaassociated (THADA)-IGF2BP3 fusions have been identified as an oncogenic event in thyroid neoplasms, but the clinical-pathologic features and subsequent management are not well-established. Here we report the findings associated with thyroid nodules with THADA-IGFBP3 fusions in our institution.
Material(s) and Method(s): FNA cytology samples of thyroid nodules during 01/2015-12/2016 with the diagnosis of atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS; Bethesda III), follicular neoplasm/ suspicious for follicular neoplasm (FN/SFN; Bethesda IV) and suspicious for malignancy (Bethesda V) with corresponding ThyroSeqV2 data were assessed. Molecular test results yielding a THADA gene fusion were identified. In addition, follow-up surgical pathology and available radiology results were reviewed.
Result(s): 186 out of 558 (33.3%) thyroid nodules displayed molecular alterations; 7 out of 186 (3.8%) Bethesda category III-V nodules with ThyroSeq molecular alterations displayed isolated THADA-IGFBP2 fusions (Table 1). The median age was 45 years. The female to male ratio was 5:2. The nodule sizes ranged from 1.8 to 5.0 cm. Four (57%) patients had surgery; three cases displayed noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) on histology; one case was a follicular adenoma. No patients had recurrence or metastasis on follow-up.
Conclusion(s): Our pilot study shows that thyroid nodules with THADA-IGF2BP3 fusions display low-risk/indolent features. These findings may aid in clinical management decisions in patients presenting with thyroid nodules with isolated THADAIGF2BP3 fusions on molecular testing

Background/Purpose: Using whole exome sequencing (WES), we identified a de novo mutation in DYSF encoding dysferlin in 2 unrelated patients with systemic inflammation and sterile pulmonary abscesses. Unlike dysferlin mutations that cause muscular dystrophies, the patients have no muscle disease, but a robust clinical response to IL-1 blockade suggested inflammasome activation and the presentation with sterile pulmonary abscess formation raised questions about an efferocytosis defect Methods: We characterized monocytes and neutrophil activation and function to assess the mechanism of the IL-1 dependent inflammation by flowcytometry, immunofluoroscence, ELISA, cytokine array, survival assay and we developed an efferocytosis assay. U937 cells expressing mutant cell line was used to further understand the mutation.
Result(s): Monocyte and monocyte-derived M1 and M2 macrophages (MDM) stimulated with LPS and ATP-released high IL-1 serum levels, that was higher in the DYSF patients' monocytes and M1 and M2 MDM compared to healthy controls (HC), and was comparable to the augmented IL-1 production in NOMID. Dysferlin colocalizes with NLRP3 in LPS activated monocyte and in M1 and M2 MDMs. Expression levels of ASC, and Caspase-1 were increased in the DYSF patients monocytes. M2-MDMs from both patients expressed proinflammatory mediators, high CXCL1(P< 0.05), CCL2, IL-6 and IL-8. We observed LPS and ATP activation-induced altered nucleur integrity in M2-MDMs from both patients (70% and 50% respectively) compared to healthy controls. In neutrophils, LPS and ATP activation did not increase IL-1b was not upregulated although MIF, IL-16 and IL-8 levels were observed. We hypothesized that either delayed neutrophil apoptosis or clearence contribute to the lung abscess formation. While neutrophil apoptosis was normal, patients' M2 MDM ability to clear healthy control neutrophils by efferocytosis was significantly impaired. Coculturing patients' neutrophils with macrophages from healthy donors didn't result in abnormal effereocytosis, thus suggesting an efferocytosis defect caused by mutant monocyte derived macrophages. The abnormal efferocyutosis was reproduced in dysferlin nutant U937 cells which showed a defect in phagosome maturation.
Conclusion(s): The de novo GOF mutation in dysferlin in two patients with systemic inflammation and sterile lung abscesses reveal a novel role of dysferlin in regulating inflammasome activation in monocytes and macrophage maturation and in neutriophil efferocytosis. Our data expand on a previously unidentified role of dysferlin in regulating M2-macrophage efferocytosis of neutrophils as a mechanisms for lung abscess formation