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Dive into the research topics where Kevin A. Peng is active.

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Featured researches published by Kevin A. Peng.


Otolaryngology-Head and Neck Surgery | 2014

Head and Neck Sarcomas: Analysis of the SEER Database

Kevin A. Peng; Tristan Grogan; Marilene B. Wang

Objective To summarize the epidemiology of sarcomas occurring in the head and neck and identify prognostic factors for patient survival. Study Design and Setting Cross-sectional analysis of the National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) program. Methods The SEER 18 registries, comprising sarcoma diagnoses made from 1973 to 2010, were queried for sarcomas arising in the head and neck. Pediatric and adult patients were analyzed separately, and multivariate and propensity-matched analyses were performed to identify predictors of disease-specific survival. Results In all, 11,481 adult cases and 1244 pediatric cases were identified. In adults, the most common histologic subtypes were malignant fibrous histiocytoma (MFH), Kaposi sarcoma, and hemangiosarcoma, while in the pediatric cohort, the most common histologic subtypes were rhabdomyosarcoma, MFH, and osteosarcoma. Cause-specific 2-, 5-, and 10-year survival rates were 76%, 66%, and 61% for adults and 84%, 73%, and 71% for pediatric patients. Multivariate analysis performed for adults revealed that male gender, absence of radiation therapy, and stage I disease were associated with improved cause-specific survival reaching statistical significance. However, a propensity-matched model demonstrated no significant difference in cause-specific survival between patients who received radiation and those who did not. Conclusion Sarcomas, a heterogeneous group of malignant mesenchymal tumors, are uncommonly found in the head and neck. This study represents the largest analysis of patients with head and neck sarcomas in the literature and demonstrates the impact of age, gender, primary site, histology, and radiation status on overall prognosis.


Clinical Imaging | 2015

Delayed intravenous contrast-enhanced 3D FLAIR MRI in Meniere’s disease: correlation of quantitative measures of endolymphatic hydrops with hearing

Ali R. Sepahdari; Gail Ishiyama; Nopawan Vorasubin; Kevin A. Peng; Michael Linetsky; Akira Ishiyama

OBJECTIVE Using three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI), our goal was to correlate quantifiable measures of endolymphatic hydrops (EH) with auditory function in the setting of Menieres disease (MD). MATERIALS AND METHODS Forty-one ears were analyzed in 21 subjects (12 ears with MD, 29 without MD). Vestibular endolymphatic space size measurements obtained with two different techniques were referenced against clinical data. RESULTS EH was better evaluated on 3D maximum intensity projections (MIPs) than on two-dimensional (2D) images. Using MIPs, quantitative assessments EH correlated with severity of hearing impairment. CONCLUSION 3D MIPs were superior to 2D images for evaluating EH in the setting of MD.


International Forum of Allergy & Rhinology | 2014

Sinonasal lymphoma: case series and review of the literature.

Kevin A. Peng; Ashley E. Kita; Jeffrey D. Suh; Sunita Bhuta; Marilene B. Wang

Sinonasal lymphoma is a rare rhinologic entity. We present a case series and review the literature surrounding the diagnosis and management of this disease.


Laryngoscope | 2013

Effects of asymmetric superior laryngeal nerve stimulation on glottic posture, acoustics, vibration

Dinesh K. Chhetri; Juergen Neubauer; Jennifer L. Bergeron; Elazar Sofer; Kevin A. Peng; Nausheen Jamal

Evaluate the effects of asymmetric superior laryngeal nerve stimulation on the vibratory phase, laryngeal posture, and acoustics.


Otolaryngology-Head and Neck Surgery | 2014

A Swallow Preservation Protocol Improves Function for Veterans Receiving Chemoradiation for Head and Neck Cancer

Kevin A. Peng; Edward C. Kuan; Lindsey Unger; William C. Lorentz; Marilene B. Wang; Jennifer L. Long

Objective Determine the efficacy of a swallow preservation protocol (SPP) on maintaining swallow function in patients undergoing chemoradiation (CRT) or radiation therapy alone (RT) for head and neck squamous cell carcinoma (HNSCC). Study design Retrospective case series. Setting Veterans Affairs medical center. Subjects and Methods Patients treated with CRT or RT for HNSCC between February 2006 and November 2013 were studied. Those enrolled in the SPP participated in swallowing, jaw, and tongue exercises during cancer therapy. The comparator group received no swallowing intervention during CRT. A previously described functional outcome swallowing scale (FOSS; 0 = no symptoms and 5 = nonoral feeding for all nutrition) was used to quantify dysphagia prior to and at the completion of cancer therapy, and an analysis was performed to compare swallowing function. Results Forty-one (all male; mean age, 66 years) and 66 patients (all male; mean age, 61 years) were included in the SPP and comparator groups, respectively. In the SPP group, mean pre- and posttreatment FOSS scores were 2.2 and 2.2, respectively, while the corresponding scores in the comparator group were 1.8 and 2.7, respectively, with posttreatment FOSS scores being significantly worse than pretreatment FOSS scores in the comparator group only. Conclusion Patients enrolled in the SPP demonstrated preserved swallowing function over the course of cancer treatment compared with a comparator group. This confirms the importance of early evaluation and intervention for dysphagia prior to and during CRT or RT alone.


American Journal of Otolaryngology | 2014

Is there a role for neck dissection in T1 oral tongue squamous cell carcinoma? The UCLA experience ☆,☆☆,★

Kevin A. Peng; Alan C. Chu; Chi Lai; Tristan Grogan; David Elashoff; Elliot Abemayor; Maie A. St. John

PURPOSE We sought to examine prognostic and therapeutic implications, including cost-effectiveness, of elective neck dissection in the management of patients with clinically-determined T1N0 oral tongue carcinoma. MATERIALS AND METHODS A retrospective review of patients with cT1N0 oral tongue squamous cell carcinoma who underwent surgical extirpation of primary tumor, with or without elective neck dissection, at UCLA Medical Center from 1990 to 2009 was performed. Cox proportional hazards regression was used to assess effects of variables on time to first loco-regional recurrence. A healthcare costs analysis of elective neck dissection was performed by querying the SEER-Medicare linked database. RESULTS Of the 123 patients identified with cT1N0 squamous cell carcinoma of the oral tongue, 88 underwent elective neck dissection at the time of tumor resection while 35 did not. For all patients, disease-free survival at 3, 5, and 10 years was 93%, 82%, and 79%. Of the 88 patients undergoing elective neck dissection, 20 (23%) demonstrated occult metastatic disease. Male gender, tumor size, perineural invasion, and occult metastatic disease were individually associated with higher rates of loco-regional recurrence. There was no significant difference in loco-regional recurrence between those who underwent elective neck dissection and those who did not (HR=0.76, p=0.52). On cost analysis, neck dissection was not associated with any significant difference in Medicare payments. CONCLUSIONS The high rate of occult metastasis (23%) following elective neck dissection, which did not confer additional healthcare costs, leads to the recommendation of elective neck dissection in patients with cT1N0 oral tongue squamous cell carcinoma.


American Journal of Neuroradiology | 2016

Blood-Labyrinth Barrier Permeability in Menière Disease and Idiopathic Sudden Sensorineural Hearing Loss: Findings on Delayed Postcontrast 3D-FLAIR MRI

M.N. Pakdaman; Gail Ishiyama; Akira Ishiyama; Kevin A. Peng; H.J. Kim; W.B. Pope; Ali R. Sepahdari

BACKGROUND AND PURPOSE: Menière disease and idiopathic sudden sensorineural hearing loss can have overlapping clinical presentation and may have similar pathophysiology. Prior studies using postcontrast 3D-FLAIR MR imaging suggest abnormal blood-labyrinth barrier permeability in both conditions, but the 2 diseases have not been directly compared by using the same imaging techniques. We hypothesized that delayed postcontrast 3D-FLAIR MR imaging would show differences in blood-labyrinth barrier permeability between Menière disease and idiopathic sudden sensorineural hearing loss. MATERIALS AND METHODS: Patients with unilateral Menière disease (n = 32) and unilateral idiopathic sudden sensorineural hearing loss (n = 11) imaged with delayed postcontrast 3D-FLAIR MR imaging were retrospectively studied. Signal intensities of the medulla and perilymph of the cochlear basal turns of both ears in each patient were measured in a blinded fashion. Cochlea/medulla ratios were calculated for each ear as a surrogate for blood-labyrinth barrier permeability. The ears were segregated by clinical diagnosis. RESULTS: Cochlea/medulla ratio was higher in symptomatic ears of patients with Menière disease (12.6 ± 7.4) than in patients with idiopathic sudden sensorineural hearing loss (5.7 ± 2.0) and asymptomatic ears of patients with Menière disease (8.0 ± 3.1), indicating increased blood-labyrinth barrier permeability in Menière disease ears. The differences in cochlea/medulla ratio between symptomatic and asymptomatic ears were significantly higher in Menière disease than in idiopathic sudden sensorineural hearing loss. Asymptomatic ears in patients with Menière disease showed higher cochlea/medulla ratio than symptomatic and asymptomatic ears in patients with idiopathic sudden sensorineural hearing loss. CONCLUSIONS: Increased cochlea/medulla ratio indicates increased blood-labyrinth barrier permeability in Menière disease compared with idiopathic sudden sensorineural hearing loss. Increased cochlea/medulla ratio in asymptomatic ears of patients with Menière disease also suggests an underlying systemic cause of Menière disease and may provide a pathophysiologic biomarker.


Laryngoscope | 2015

Sinonasal outcomes in obstructive sleep apnea syndrome

Edward C. Kuan; Bobby A. Tajudeen; Kevin A. Peng; Marilene B. Wang

Obstructive sleep apnea syndrome (OSAS) is a common adult and pediatric sleep disorder, which, if left untreated, is associated with severe medical consequences. Otolaryngologists are often challenged by the impact of OSAS on sinonasal symptoms, as well as by the contribution of primary nasal disorders to exacerbation of OSAS. The objectives of this study are to explore the relationship between patients with known OSAS and quality‐of‐life outcomes as measured by 22‐iem Sino‐Nasal Outcome Test (SNOT‐22) questionnaire scores.


Annals of Otology, Rhinology, and Laryngology | 2015

Utility of the transnasal esophagoscope in the management of chemoradiation-induced esophageal stenosis.

Kevin A. Peng; Aaron J. Feinstein; Jonathan Salinas; Dinesh K. Chhetri

Objective: This study aimed to describe management of esophageal stenosis after chemoradiation therapy for head and neck squamous cell carcinoma (HNSCC), with particular emphasis on techniques and outcomes with the use of the transnasal esophagoscope (TNE) in the office as well as operating room settings. Methods: Retrospective analysis of all patients with esophageal stenosis following head and neck cancer radiation, with or without chemotherapy, and managed with TNE-assisted esophageal dilation over a 5-year period. Preoperative and postoperative swallowing function were assessed objectively with the Functional Outcome Swallowing Scale (FOSS; ranging from score 0, a normal diet, to score 5, complete dependence on nonoral nutrition). Results: Twenty-five patients met inclusion criteria. The mean pretreatment FOSS score was 4.4, whereas the mean posttreatment FOSS score was 2.7 (Wilcoxon signed-rank test, P < .001). Prior to dilation, 16 patients were completely gastrostomy-tube dependent (FOSS 5), of whom 12 (75%) were able to tolerate oral nutrition for a majority of their diet following treatment according to our protocol. No complications were noted. Conclusion: Dysphagia following chemoradiation therapy for HNSCC is often related to esophageal stenosis. With the aid of TNE, we have developed a successful treatment strategy for esophageal stenosis with improved success rates.


American Journal of Otolaryngology | 2016

Laryngeal oncocytic cystadenomas masquerading as laryngoceles

Aaron J. Feinstein; Kevin A. Peng; Sunita Bhuta; Elliot Abemayor; Abie H. Mendelsohn

OBJECTIVE To describe an experience with laryngeal oncocytic cystadenomas and review the published literature regarding this uncommon diagnosis. METHODS AND RESULTS A clinical review of patients presenting with cystic laryngeal masses in an urban academic medical center between January and December 2013 was performed. Three patients, two female and one male, with a mean age of 68 years, were diagnosed with oncocytic cystadenomata of the larynx. Major presenting symptoms included dysphonia, globus, and ipsilateral otalgia. Endoscopic examinations revealed a cystic structure arising from varied subsites of the larynx: laryngeal ventricle, aryepiglottic fold, and pre-epiglottic space. Cross-sectional radiographic imaging was obtained in each case. The patients were treated with transoral (CO2) laser microsurgery (TLM). In all three cases, pathological analysis revealed oncocytic cystadenoma with clear margins. CONCLUSIONS Oncocytic cystadenoma is a rare entity of the larynx predominantly affecting elderly patients. Clinical presentation and imaging may suggest the diagnosis of an internal laryngocele. Complete excision is both diagnostic and therapeutic, and typically can be achieved using TLM. When clear margins are obtained, no adjuvant therapy is indicated. Although laryngoceles and malignancies are more commonly encountered, oncocytic cystadenomas should remain in the differential of cystic laryngeal masses.

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Edward C. Kuan

University of California

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Jeffrey D. Suh

University of California

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Akira Ishiyama

University of California

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Ashley E. Kita

University of California

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Eric P. Wilkinson

Huntington Medical Research Institutes

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Gail Ishiyama

University of California

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