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Dive into the research topics where Demetri Arnaoutakis is active.

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Featured researches published by Demetri Arnaoutakis.


Cancer Research | 2014

Activation of the NOTCH pathway in Head and Neck Cancer

Wenyue Sun; Daria A. Gaykalova; Michael F. Ochs; Elizabeth Mambo; Demetri Arnaoutakis; Yan Liu; Myriam Loyo; Nishant Agrawal; Jason Howard; Ryan Li; Sun Ahn; Elana Fertig; David Sidransky; Jeffery Houghton; Kalyan Buddavarapu; Tiffany Sanford; Ashish Choudhary; Will Darden; Alex Adai; Gary J. Latham; Justin A. Bishop; Rajni Sharma; William H. Westra; Patrick T. Hennessey; Christine H. Chung; Joseph A. Califano

NOTCH1 mutations have been reported to occur in 10% to 15% of head and neck squamous cell carcinomas (HNSCC). To determine the significance of these mutations, we embarked upon a comprehensive study of NOTCH signaling in a cohort of 44 HNSCC tumors and 25 normal mucosal samples through a set of expression, copy number, methylation, and mutation analyses. Copy number increases were identified in NOTCH pathway genes, including the NOTCH ligand JAG1. Gene set analysis defined a differential expression of the NOTCH signaling pathway in HNSCC relative to normal tissues. Analysis of individual pathway-related genes revealed overexpression of ligands JAG1 and JAG2 and receptor NOTCH3. In 32% of the HNSCC examined, activation of the downstream NOTCH effectors HES1/HEY1 was documented. Notably, exomic sequencing identified 5 novel inactivating NOTCH1 mutations in 4 of the 37 tumors analyzed, with none of these tumors exhibiting HES1/HEY1 overexpression. Our results revealed a bimodal pattern of NOTCH pathway alterations in HNSCC, with a smaller subset exhibiting inactivating NOTCH1 receptor mutations but a larger subset exhibiting other NOTCH1 pathway alterations, including increases in expression or gene copy number of the receptor or ligands as well as downstream pathway activation. Our results imply that therapies that target the NOTCH pathway may be more widely suitable for HNSCC treatment than appreciated currently.


Archives of Otolaryngology-head & Neck Surgery | 2013

Impact of Pharyngeal Closure Technique on Fistula After Salvage Laryngectomy

Urjeet A. Patel; Brian Moore; Mark K. Wax; Eben L. Rosenthal; Larissa Sweeny; Oleg Militsakh; Joseph A. Califano; Alice C. Lin; Christian P. Hasney; R. Brent Butcher; Jamie Flohr; Demetri Arnaoutakis; Matthew G. Huddle; Jeremy D. Richmon

IMPORTANCE No consensus exists as to the best technique, or techniques, to optimize wound healing, decrease pharyngocutaneous fistula formation, and shorten both hospital length of stay and time to initiation of oral intake after salvage laryngectomy. We sought to combine the recent experience of multiple high-volume institutions, with different reconstructive preferences, in the management of pharyngeal closure technique for post-radiation therapy salvage total laryngectomy in an effort to bring clarity to this clinical challenge. OBJECTIVE To determine if the use of vascularized flaps in either an onlay or interposed fashion reduces the incidence or duration of pharyngocutaneous fistula after salvage laryngectomy compared with simple primary closure of the pharynx. DESIGN Multi-institutional retrospective review of all patients undergoing total laryngectomy after having received definitive radiation therapy with or without chemotherapy between January 2005 and January 2012, conducted at 7 academic medical centers. SETTING Academic, tertiary referral centers. PATIENTS The study population comprised 359 patients from 8 institutions. All patients had a history of laryngeal irradiation and underwent laryngectomy between 2005 and 2012. They were grouped as primary closure, pectoralis myofascial onlay flap, or interposed free tissue. All patients had a minimum of 4 months follow-up. MAIN OUTCOMES AND MEASURES Fistula incidence, severity, and predictors of fistula. RESULTS Of the 359 patients, fistula occurred in 94 (27%). For patients with fistula, hospital stay increased from 8.9 to 12.1 days (P < .001) and oral diet initiation was delayed from 10.5 days to 29.9 days (P < .001). Patients were grouped according to closure technique: primary closure (n = 99), pectoralis onlay flap (n = 40), and interposed free tissue (n = 220). Incidence of fistula with primary closure was 34%. For the interposed free flap group, the fistula rate was lower at 25% (P = .07). Incidence of fistula was the lowest for the pectoralis onlay group at 15% (P = .02). Multivariate analysis confirmed a significantly lower fistula rate with either flap technique. For patients who developed fistula, mean duration of fistula was significantly prolonged with primary closure (14.0 weeks) compared with pectoralis flap (9.0 weeks) and free flap (6.5 weeks). CONCLUSIONS AND RELEVANCE Pharyngocutaneous fistula remains a significant problem following salvage laryngectomy. Use of nonirradiated, vascularized flaps reduced the incidence and duration of fistula and should be considered during salvage laryngectomy.


Clinical Cancer Research | 2012

Detection of TIMP3 promoter hypermethylation in salivary rinse as an independent predictor of local recurrence-free survival in head and neck cancer

Wenyue Sun; David Zaboli; Hao Wang; Yan Liu; Demetri Arnaoutakis; Tanbir Khan; Zubair Khan; Wayne M. Koch; Joseph A. Califano

Purpose: To validate a panel of methylation-based salivary rinse biomarkers (P16, CCNA1, DCC, TIMP3, MGMT, DAPK, and MINT31) previously shown to be independently associated with poor overall survival and local recurrence in a larger, separate cohort of patients with head and neck squamous cell carcinoma (HNSCC). Experimental Design: One hundred ninety-seven patients were included. All pretreatment saliva DNA samples were evaluated for the methylation status of the gene promoters by quantitative methylation-specific PCR. The main outcome measures were overall survival, local recurrence-free survival, and disease-free survival. Results: In univariate analyses, the detection of hypermethylation of CCNA1, MGMT, and MINT31 was significantly associated with poor overall survival; the detection of hypermethylation of TIMP3 was significantly associated with local recurrence-free survival; and the detection of hypermethylation of MINT31 was significantly associated with poor disease-free survival. In multivariate analyses, detection of hypermethylation at any single marker was not predictive of overall survival in patients with HNSCC; detection of hypermethylation of TIMP3 in salivary rinse had an independent, significant association with local recurrence-free survival (HR = 2.51; 95% CI: 1.10–5.68); and none of the studied markers was significantly associated with disease-free survival. Conclusion: The detection of promoter hypermethylation of the seven genes in salivary rinse as an independent prognostic indicator of overall survival in patients with HNSCC was not validated. Detection of promoter hypermethylation of TIMP3 in pretreatment salivary rinse is independently associated with local recurrence-free survival in patients with HNSCC and may be a valuable salivary rinse biomarker for HNSCC recurrence. Clin Cancer Res; 18(4); 1082–91. ©2012 AACR.


Oral Oncology | 2013

Recurrence patterns and management of oral cavity premalignant lesions.

Demetri Arnaoutakis; Justin A. Bishop; William H. Westra; Joseph A. Califano

OBJECTIVE To gain an understanding of head and neck mucosal premalignant recurrence and progression based on histology, treatment modality, and risk factors. DESIGN Retrospective chart review. SETTING Academic medical center. PATIENTS Patients who were followed or treated for oral cavity dysplasia/carcinoma in situ. MAIN OUTCOMES MEASURES Comparisons with clinical features, degree of dysplasia, anatomical location, rate of recurrences as well as malignant transformation and overall outcome were made. RESULTS Of the 136 patients who were included in the study, 20% (n = 27) initially presented with mild dysplasia, 39% (n = 53) with moderate dysplasia, 21% (n = 29) with severe dysplasia, and 20% (n = 27) with carcinoma in situ. Wide local excision (HR 0.54, p = 0.05) was associated with reduced local recurrence in comparison to observation. In comparison to observation, both wide local excision (HR 0.43, p = 0.04) and CO(2)/NO Yag laser treatment (HR 0.14, p = 0.02) of dysplastic lesions significantly reduced progression to cancer. Management of mild dysplasia included observation (n = 13), excision (n = 10) and laser therapy (n = 3). Six of the 13 observed patients suffered a premalignancy recurrence, whereas only 4 of the 13 patients who underwent excision/laser treatment experienced a recurrence. Similarly, 5/13 observed patients eventually progressed to malignancy in comparison to only 2/13 patients who underwent initial excision/laser treatment. CONCLUSION Wide excision and/or ablation of head and neck mucosal premalignancy is more effective than observation in preventing recurrence of premalignancy and progression to malignancy. Mild dysplasia has a potentially high rate of recurrence and progression to malignancy when observed, and may be treated by wide excision or ablation.


American Journal of Otolaryngology | 2015

Pharyngocutaneous fistula after total laryngectomy: A single-institution experience, 2001–2012

Eleni M. Benson; Richard M. Hirata; Carol B. Thompson; Patrick K. Ha; Carole Fakhry; John R. Saunders; Joseph A. Califano; Demetri Arnaoutakis; Marshall A. Levine; Mei Tang; Geoffrey Neuner; Barbara Messing; Ray Blanco

PURPOSE The purpose of this study was to determine the incidence of and risk factors for pharyngocutaneous fistula in patients undergoing total laryngectomy at a single institution. MATERIALS AND METHODS The records of 59 patients undergoing primary or salvage total laryngectomy at our institution from 2001 to 2012 were retrospectively reviewed. Data collected included patient, tumor and treatment characteristics, and surgical technique. Risk factors were analyzed for association with pharyngocutaneous fistula formation. RESULTS Twenty patients (34%) developed fistulas. Preoperative tracheostomy (OR 4.1; 95% CI 1.3-13 [p=0.02]) and low postoperative hemoglobin (OR 9.1; 95% CI 1.1-78 [p=0.04]) were associated with fistula development. Regarding surgical technique, primary sutured closure of the total laryngectomy defect had the lowest fistula rate (11%). In comparison, primary stapled closure and pectoralis onlay flap over primary closure had nonsignificantly increased fistula rates (43%, OR 6.0; 95% CI 1.0-37.3 [p=0.06] and 25%, OR 2.7; 95% CI 0.4-23.9 [p=0.38], respectively). Pectoralis flap incorporated into the suture line had a significantly increased fistula rate (50%, OR 7.1; 95% CI 1.4-46 [p=0.02]). After stratification for salvage status, patient comorbidities were associated with fistula in non-salvage cases whereas disease-related characteristics were associated with fistula in salvage cases. Fistula development was associated with increased length of hospital stay (p<0.001) and increased time before oral diet initiation (p<0.001). CONCLUSIONS Pharyngocutaneous fistula is a common complication of total laryngectomy. Preoperative tracheostomy, postoperative hemoglobin, and surgical technique are important in determining the risk of fistula.


Craniomaxillofacial Trauma and Reconstruction | 2014

Facial Nerve Trauma: Evaluation and Considerations in Management

Eli Gordin; Thomas S. Lee; Yadranko Ducic; Demetri Arnaoutakis

The management of facial paralysis continues to evolve. Understanding the facial nerve anatomy and the different methods of evaluating the degree of facial nerve injury are crucial for successful management. When the facial nerve is transected, direct coaptation leads to the best outcome, followed by interpositional nerve grafting. In cases where motor end plates are still intact but a primary repair or graft is not feasible, a nerve transfer should be employed. When complete muscle atrophy has occurred, regional muscle transfer or free flap reconstruction is an option. When dynamic reanimation cannot be undertaken, static procedures offer some benefit. Adjunctive tools such as botulinum toxin injection and biofeedback can be helpful. Several new treatment modalities lie on the horizon which hold potential to alter the current treatment algorithm.


PLOS ONE | 2012

Comparison of Promoter Hypermethylation Pattern in Salivary Rinses Collected with and without an Exfoliating Brush from Patients with HNSCC

Wenyue Sun; David Zaboli; Yan Liu; Demetri Arnaoutakis; Tanbir Khan; Hao Wang; Wayne M. Koch; Zubair Khan; Joseph A. Califano

Background Salivary rinses have been recently proposed as a valuable resource for the development of epigenetic biomarkers for detection and monitoring of head and neck squamous cell carcinoma (HNSCC). Both salivary rinses collected with and without an exfoliating brush from patients with HNSCC are used in detection of promoter hypermethylation, yet their correlation of promoter hypermethylation has not been evaluated. This study was to evaluate the concordance of promoter hypermethylation between salivary rinses collected with and without an exfoliating brush from patients with HNSCC. Methodolgy 57 paired salivary rinses collected with or without an exfoliating brush from identical HNSCC patients were evaluated for promoter hypermethylation status using Quantitative Methylation-Specific PCR. Target tumor suppressor gene promoter regions were selected based on our previous studies describing a panel for HNSCC screening and surveillance, including P16, CCNA1, DCC, TIMP3, MGMT, DAPK and MINT31. Principal Findings In salivary rinses collected with and without brush, frequent methylation was detected in P16 (8.8% vs. 5.2%), CCNA1 (26.3% vs. 22.8%), DCC (33.3% vs. 29.8%), TIMP3 (31.6% vs. 36.8%), MGMT (29.8% vs. 38.6%), DAPK (14.0% vs. 19.2%), and MINT31 (10.5% vs. 8.8%). Spearmans rank correlation coefficient showed a positive correlation between salivary rinses collected with and without brush for P16 (ρ = 0.79), CCNA1 (ρ = 0.61), DCC (ρ = 0.58), TIMP3 (ρ = 0.10), MGMT (ρ = 0.70), DAPK (ρ = 0.51) and MINT31 (ρ = 0.72) (P<0.01). The percent agreement of promoter methylation between salivary rinses with brush and without brush were 96.5% for P16, 82.5% for CCNA1, 78.9% for DCC, 59.7% for TIMP3, 84.2% for MGMT, 84.2% for DAPK, and 94.7% for MINT31. Conclusions Our study demonstrated strong correlations of gene promoter hypermethylation between salivary rinses collected with and without an exfoliating brush. Salivary rinse collection without using an exfoliating brush may offer a cost effective, rapid, non-invasive, and reliable means for development of epigenetic salivary rinse biomarkers.


Otolaryngology-Head and Neck Surgery | 2017

Endoscopic Lateral Cartilage Graft Tympanoplasty

Cameron C. Wick; Demetri Arnaoutakis; Vivian F. Kaul; Brandon Isaacson

Objective To describe a novel technique for lateral graft tympanoplasty. Study Design Case series with chart review. Setting Tertiary care university hospital. Subjects and Methods Pediatric and adult patients with tympanic membrane perforations deemed unfavorable for a medial graft technique due to the perforation characteristics or myringitis. Results Between 2014 and 2016, 34 ears from 31 patients underwent a transcanal endoscopic lateral cartilage graft tympanoplasty. The mean age was 24.4 years (range, 6-71 years), and 22 patients (65%) were younger than 18 years. All patients had tympanic membrane perforations. Eighteen patients (53%) had total or near-total perforations, leaving a minimal anterior remnant, and 16 patients (47%) had extensive myringitis. A bisected tragal cartilage-perichondrium shield graft was used in 33 patients (97%). The mean (SD) follow-up length was 9.8 (5.7) months. Initial perforation closure rate was 88.2% (30/34). Three of the persistent perforations underwent a revision endoscopic medial graft tympanoplasty with successful closure, leaving a final closure rate of 97.1% (33/34). Five patients (15%) required topical therapy for postoperative myringitis. Mean (SD) pure-tone average and air-bone gap significantly improved by 11.5 (10.7) dB (P < .001) and 11.4 (10.6) dB (P < .001), respectively. Twenty-seven patients (79%) closed their air-bone gap within 20 dB. Conclusion Transcanal endoscopic lateral cartilage graft tympanoplasty is feasible, and initial data support favorable outcomes. Further data are necessary for evaluation of long-term results and efficacy comparisons.


Archives of Otolaryngology-head & Neck Surgery | 2017

Zika Virus—What the Otolaryngologist Should Know: A Review

Demetri Arnaoutakis; Tapan A. Padhya

Importance Initially discovered in 1947, Zika virus infection received little notoriety as a tropical disease until 2015 when an outbreak of microcephaly cases was reported in Brazil. Zika is a single-stranded RNA arbovirus of the Flaviviridae family. The primary source of infection in humans stems from Aedes aegypti mosquito bites but can also occur through sexual, blood, and perinatal transmission. With expectations that 3 to 4 million people across the Americas will be infected over the next year, the World Health Organization has declared this event a Public Health Emergency of International Concern. Observations Although acute Zika virus infection is typically mild and self-limited, researchers have demonstrated serious neurologic complications associated with it such as microcephaly and Guillain-Barre syndrome. Otolaryngologists should be aware of head and neck manifestations which include conjunctivitis, retro-orbital pain, cephalgia, and odynophagia. The Centers for Disease Control and Prevention have developed specific molecular and serologic testing protocols and algorithms for follow-up care of suspected cases. Currently, the mainstay of management is conservative care while researchers attempt to develop a vaccine. Strategies to contain the Zika virus include vector control, travel restriction for women who are pregnant or trying to become pregnant, and avoidance of mosquito bites in endemic regions of the world. Conclusions and Revelance The future outlook regarding the current Zika virus outbreak in the Americas remains uncertain. What is certain is our need to promptly and efficiently address research gaps in our understanding of clinical outcomes from infection and environmental factors that influence emergence meanwhile improving diagnostic, therapeutic, and preventive measures against the disease.


Otology & Neurotology | 2017

Endoscopic transcanal transpromontorial approach for vestibular schwannoma resection: A case series

Cameron C. Wick; Demetri Arnaoutakis; Samuel L. Barnett; Alejandro Rivas; Brandon Isaacson

OBJECTIVE To demonstrate successful surgical management of vestibular schwannomas via an exclusively endoscopic transcanal transpromontorial approach (EETTA). PATIENTS Four patients with vestibular schwannomas. INTERVENTIONS Surgical excision via EETTA. MAIN OUTCOMES Technique refinements, tumor access, complete tumor removal, and patient morbidity. RESULTS Three tumors were Koos grade I and one tumor was Koos grade II. All ears had non-serviceable hearing prior to surgery. The EETTA enabled access to the internal auditory canal and porus acousticus as well as limited access to the cerebellopontine angle. Gross total tumor resection was achieved in all cases. There were no intraoperative or postoperative complications and the mean hospital duration was 2.8 days. After a mean follow-up of 5.0 months, all cases had a good facial nerve outcome. CONCLUSIONS The EETTA can be successfully used for the management of small vestibular schwannomas in ears without serviceable hearing. Additional studies are needed to fully elucidate the risk-benefit profile of this minimally invasive approach.

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Yadranko Ducic

University of Texas Southwestern Medical Center

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Brandon Isaacson

University of Texas Southwestern Medical Center

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Cameron C. Wick

University of Texas Southwestern Medical Center

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Wenyue Sun

Johns Hopkins University

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Yan Liu

Johns Hopkins University

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Justin A. Bishop

University of Texas Southwestern Medical Center

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