About

Arnaud F. Bewley, M.D., is the Chair of the Department of Otolaryngology, Director of the Division of Head & Neck Surgery, and a Professor in the Department of Otolaryngology at UC Davis Health. He is a fellowship-trained head and neck cancer and reconstructive surgeon whose practice focuses on the comprehensive management of tumors of the head and neck, including benign and malignant tumors of the face, mouth, throat, neck, and thyroid. Dr. Bewley has a special interest in utilizing microvascular free-flap techniques to optimize patients' post-operative appearance and function. His research interests include designing treatment protocols for advanced skin cancers to improve cure rates and reduce side effects, employing minimally invasive transoral robotic surgery to remove head and neck tumors, and analyzing the cost of care for head and neck cancer to promote cost-effective healthcare resource utilization. He is also involved in developing novel simulation training for residents in managing acute and emergency clinical scenarios. Dr. Bewley's background includes a B.A. in Physics from Yale University, an M.D. from Columbia University, and specialized training through internships, residencies, and fellowships at institutions such as the University of Pennsylvania, University of South Carolina, and Medical University of South Carolina.

Research topics

• Medicine
• Artificial Intelligence
• Computer Science
• Surgery
• Internal medicine
• Pathology
• Radiology
• Family medicine
• Physics
• Biology
• Management
• Demography
• Engineering
• Medical education
• Biomedical engineering

Selected publications

• Head and neck cancer surgery and label-free fluorescence lifetime imaging (FLIm)

  2026-03-04

  article

  We pair multispectral label-free FLIm with a data-centric AI model to generate real-time tumor-margin maps during head-and-neck cancer surgery. In a 92-patient study, confident-learning pruning and gradient-boosted trees achieved an AUC of 0.94 under leave-one-patient-out validation, with real time overlays rendered in 41 milliseconds latency. Borderline predictions tracked metabolic transitions in spectral channels associated with NADH- and FAD autofluorescence and remained robust across anatomical sites and HPV status. The framework offers accurate, clinical workflow-compatible guidance for surgeons and promising safer resections.

  PublisherDOI

• Enhancing Label-Free Fluorescence Lifetime Imaging for Intraoperative Tumor Margin Delineation in Head and Neck Cancer using Data-Centric AI

  Research Square · 2025-05-23 · 1 citations

  preprintOpen access
  PublisherOA PDFDOI

• Association of Social Vulnerability Index With Declining Recommended Surgical Treatment in Head and Neck Cancer Patients

  The Laryngoscope · 2025-01-08 · 6 citations

  article

  OBJECTIVE: To investigate the impact of county-level social vulnerability on patients' decision to refuse recommended surgical treatment. METHODS: Retrospective cohort analysis conducted on HNSCC cases documented in the latest available SEER databases from 2000 to 2020; various demographic, including county of residence, and disease-related variables were collected. CDC's Social Vulnerability Index (SVI) was assigned based on patients' county of residence, and patients were subsequently categorized into four SVI quartiles. Pearson chi-square tests and binomial logistic regression was conducted to determine the impact of variables on patients' refusal of surgical treatment. RESULTS: Among 83,184 patients, 2.6% (2,165) refused surgical intervention recommended by their physician as part of treatment. Social vulnerability (higher SVI), male sex, older age, more advanced disease stage, belonging to non-Hispanic Black or Native Hawaiian/Asian Pacific Islander Race and Origin, and single marital status were associated with higher likelihood of refusing surgery. CONCLUSION: SVI is a significant factor in the refusal of recommended surgical treatment in HNSCC patients. Advanced disease stages and social vulnerability appear to interplay, influencing treatment decisions. Culturally competent care and support for socially vulnerable patients may mitigate disparities in treatment acceptance, potentially improving survival outcomes. LEVEL OF EVIDENCE: 3 Laryngoscope, 135:2062-2069, 2025.

  PublisherDOI

• Fibula Free Flap Reconstruction of Cervical Spine Defects: A Multi‐Institutional Study

  The Laryngoscope · 2024-07-10 · 1 citations

  article

  INTRODUCTION: Cervical spine defects result in spinal instability, putting the spinal cord and vertebral arteries at risk of damage and possibly devastating neurological injuries. The fibula free flap can span the spinal defects for stability. There is a paucity of literature on this technique. METHOD: Multi-institutional retrospective case series reviewing patients who underwent cervical spine reconstruction with a fibula free flap. Patient demographic information, comorbidities, characteristics of cervical spine defects, and free flap complications were collected. RESULTS: A total of 1187 fibula free flaps across 10 different institutions were reviewed. Thirteen patients (1.09%) underwent cervical spine reconstruction with a fibula free flap. Average age was 52.3 years old with an age range of 12-79 years. There were six males (46.1%) and seven females (53.8%). The most common defect etiology was infection (n = 6, 46.1%). Most commonly involved cervical spine level of the defect was C5 (n = 10) followed by C6 (n = 9) and C4 (n = 8). The majority of reconstructed defects spanned three or more cervical levels, (n = 9, 69.2%). Facial artery was the most common arterial anastomosis (n = 8). Eight patients (61.5%) required a tracheostomy during their postoperative course. None of the patients had symptomatic or radiographic nonunion. CONCLUSION: This case series demonstrates that a vascularized fibula flap is a potential reconstructive option for cervical spine defects, especially in defects greater than three cervical levels, in the setting of infection, and previously radiated patients. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:4923-4928, 2024.

  PublisherDOI

• Investigating fluorescence lifetime signatures for normal tissue adjacent to cancer in oropharyngeal squamous cell carcinomas

  2024-03-13

  article

  We present a study investigating fluorescence lifetime signatures of normal tissues adjacent to tumors (NATs) in head and neck squamous cell carcinoma (HNSCC) using fluorescence lifetime imaging (FLIm). Label-free FLIm offers insight into the metabolic activity and extracellular matrix composition. Understanding the metabolic activity, tissue heterogeneity and tumor-associated alterations in these transition areas can enhance the accuracy of margin delineation. Initial results show that the fluorescence lifetime is gradually increasing from shorter to longer lifetimes with increasing distance from the cancer and with varying magnitudes of change being observed in the individual emission bands.

  PublisherDOI

• Early Detection of Lymph Node Metastasis Using Primary Head and Neck Cancer Computed Tomography and Fluorescence Lifetime Imaging

  Diagnostics · 2024-09-23 · 2 citations

  articleOpen access

  Objectives: Early detection and accurate diagnosis of lymph node metastasis (LNM) in head and neck cancer (HNC) are crucial for enhancing patient prognosis and survival rates. Current imaging methods have limitations, necessitating new evaluation of new diagnostic techniques. This study investigates the potential of combining pre-operative CT and intra-operative fluorescence lifetime imaging (FLIm) to enhance LNM prediction in HNC using primary tumor signatures. Methods: CT and FLIm data were collected from 46 HNC patients. A total of 42 FLIm features and 924 CT radiomic features were extracted from the primary tumor site and fused. A support vector machine (SVM) model with a radial basis function kernel was trained to predict LNM. Hyperparameter tuning was conducted using 10-fold nested cross-validation. Prediction performance was evaluated using balanced accuracy (bACC) and the area under the ROC curve (AUC). Results: The model, leveraging combined CT and FLIm features, demonstrated improved testing accuracy (bACC: 0.71, AUC: 0.79) over the CT-only (bACC: 0.58, AUC: 0.67) and FLIm-only (bACC: 0.61, AUC: 0.72) models. Feature selection identified that a subset of 10 FLIm and 10 CT features provided optimal predictive capability. Feature contribution analysis identified high-pass and low-pass wavelet-filtered CT images as well as Laguerre coefficients from FLIm as key predictors. Conclusions: Combining CT and FLIm of the primary tumor improves the prediction of HNC LNM compared to either modality alone. Significance: This study underscores the potential of combining pre-operative radiomics with intra-operative FLIm for more accurate LNM prediction in HNC, offering promise to enhance patient outcomes.

  PublisherOA PDFDOI

• Thyroid Cancer Bone Metastasis

  2024-01-01

  book-chapterSenior authorCorresponding
  PublisherDOI

• Mesoscopic FLIm for detection of residual cancer in transoral robotic surgery

  2024-03-13

  article

  This study introduces mesoscopic FLIm as a potential solution to address the challenge of residual cancer in Transoral Robotic Surgery. Current methods rely on intraoperative frozen sections analysis (IFSA), which can yield false negatives. FLIm utilizes tissue fluorophores to delineate head and neck cancer in the surgical cavity accurately. A FLIm-based semi-supervised classification model was developed using data from 22 patients, achieving a sensitivity of 0.75 for residual tumors and an overall tissue specificity of 0.78. The proposed approach also outperformed IFSA in detecting positive surgical margins. FLIm shows promise in guiding TORS and improving surgical outcomes.

  PublisherDOI

• The Effect of Risk Factors on the Fluorescence Lifetime in Oropharyngeal Cancer

  2024-01-01

  article

  Employing label-free fluorescence lifetime imaging for cancer margin delineation during oropharyngeal resection surgery is impeded by molecular alterations from risk factors (alcohol, tobacco, HPV). Improved discrimination is observed in HPV-negative cancer compared to HPV-positive cases.

  PublisherDOI

• Functional Laryngectomy and Quality of Life in Survivors of Head and Neck Cancer With Intractable Aspiration

  JAMA Otolaryngology–Head & Neck Surgery · 2024-03-07 · 9 citations

  articleOpen access

  Importance: Late effects of head and neck cancer (HNC) treatment include profound dysphagia, chronic aspiration, and death. Functional laryngectomy (FL) can improve patient survival and quality of life (QoL); however, removing a failing larynx for a noncancer reason is a difficult decision. Data regarding the ability of FL to improve self-perceptions of voice, swallowing, and QOL in survivors of HNC with intractable aspiration are inconclusive. Objective: To investigate the association of FL with changes in self-reported perceptions of voice, swallowing, oral intake, QoL, and mood in survivors of HNC experiencing profound dysphagia and intractable aspiration. Design, Settings, and Participants: This cohort study was conducted at a single academic institution and included survivors of HNC with profound swallowing dysfunction and intractable aspiration who underwent FL from July 2016 through March 2022. Of the initial 22 patients enrolled, 2 patients (15%) died of aspiration pneumonia before receiving FL. Data analyses were performed from July 2016 through March 2023. Main Outcomes and Measures: Self-reported measures of voice using the VHI (30-item Voice Handicap Index), swallowing using the EAT-10 (10-item Eating Assessment Tool), functional oral intake scale using the FOIS (Functional Oral Intake Scale), and quality of life using the FACT-H&N (Functional Assessment of Cancer Therapy-Head & Neck) were assessed before FL and at 1, 3, and 6 months after FL. Mood states were evaluated using the POMS (Profile of Mood States, second edition), before FL and at 6 months after FL. Results: The study analyses included 20 patients (mean [SD] age, 72.4 (7.0) years; 19 [95%] males and 1 [5%] female) who underwent FL and had complete data across all time points. Among these, 12 patients (60%) had received chemoradiation for oropharyngeal, 7 (35%) for laryngeal, or 1 (5%) for nasopharyngeal cancer. The mean (SD) time from completion of oncologic treatment to FL was 15.5 (5.5) years. Mean (SD) score on the EAT-10 improved from 33.2 (7.4) to 23.1 (10.8) at 1 month; 12.1 (9.1) at 3 months; and 8.3 (7.4) at 6 months, with a large effect size (η2 = 0.72; 95% CI, 0.54-0.80). Mean (SD) score on the FOIS improved from 2.0 (1.5) to 2.9 (1.7) at 1 month; 4.8 (2.5) at 3 months; and 5.2 (1.7) at 6 months, with a large effect size (η2 = 0.6; 95% CI, 0.38-0.71). Improvement in oral intake was achieved in 19 patients (95%), and feeding tubes were removed in 10 of 16 patients (63%) who were feeding tube-dependent; 6 patients (27%) continued to require supplemental tube feedings. Mean (SD) score on the VHI improved from 63.6 (34.0) to 86.9 (33.7) at 1 month; 71.3 (36.1) at 3 months; and 39.7 (26.9) at 6 months, with a large effect size (η2 = 0.42; 95% CI, 0.19-0.56). Seventeen patients (85%) were able to use a tracheoesophageal voice prosthesis for alaryngeal communication. Mean (SD) score on the FACT-H&N improved from 86.2 (17.8) to 93.6 (18.4) at 1 month; 109.0 (18.4) at 3 months; and 121.0 (16.8) at 6 months, with a large effect size (η2 = 0.64; 95% CI, 0.42-0.74). Mean (SD) score on the POMS improved from 58.9 (13.2) at baseline to 44.5 (9.9) at 6 months, with a large effect size (Cohen d = 1.04; 95% CI, 0.48-1.57). None of the patients experienced major complications of FL; 1 patient (5%) had a postoperative pharyngocutaneous fistula. Conclusions and Relevance: The findings of this cohort study indicate that FL was associated with marked improvements in self-perception of voice and swallowing, functional oral intake, QoL, and mood state among survivors of HNC. These findings can serve as a framework for FL counseling among HNC survivors experiencing profound dysphagia and intractable aspiration.

  PublisherOA PDFDOI

Frequent coauthors

• D. Gregory Farwell

  Hospital of the University of Pennsylvania

  42 shared

• Meenhard Herlyn

  32 shared

• Gregory S. Weinstein

  University of Pennsylvania

  32 shared

• Steven M. Sperry

  31 shared

• Kati Räsänen

  31 shared

• Anil K. Rustgi

  Columbia University Irving Medical Center

  31 shared

• Phyllis A. Gimotty

  31 shared

• Kathleen T. Montone

  University of Pennsylvania

  30 shared

Awards & honors

• Sacramento Top Doctors (2017, 2018, 2019, 2020, 2021)
• AHNS Service Award as Secretary of AHNS CDMS (2020)
• AAO-HNS Committee Excellence Award as member of AAO-HNS HNSE…
• Resident Teaching Award- Department of Otolaryngology (2016)
• Honorable Mention - AHNS poster competition (2012)