Dominic H Moon1, Sung Ho Moon2, Kyle Wang1, Mark C Weissler3, Trevor G Hackman3, Adam M Zanation3, Brian D Thorp3, Samip N Patel3, Jose P Zevallos3, Lawrence B Marks1, Bhishamjit S Chera4. 1. Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States. 2. Department of Radiation Oncology, Research Institute and Hospital, National Cancer Center, Goyang, South Korea. 3. Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States. 4. Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States. Electronic address: bchera@med.unc.edu.
Abstract
OBJECTIVES: To evaluate the incidence of, and risk factors associated with, mandibular osteoradionecrosis (MORN) following radiation therapy (RT) for oral cavity and oropharyngeal cancers. MATERIALS AND METHODS: Patient and treatment records of 252 consecutive patients with oral cavity or oropharynx cancers treated with RT by a single radiation oncologist at a high volume academic institution from August 2009 to December 2015 were retrospectively reviewed. A Cox regression model was used to assess factors associated with the development of MORN. RT dosimetry was compared between patients with MORN and a matched cohort of patients without MORN. RESULTS: MORN developed in 14 patients (5.5%), occurring 3-40 (median 8) months post-RT. Factors associated with MORN on univariable analysis included primary diagnosis of oral cavity vs oropharynx cancer (hazard ratio [HR]: 3.0, p=0.04), smoking at the time of RT (HR: 3.1, p=0.04), mandibular invasion of the primary (HR: 3.7, p=0.04), pre-RT tooth extraction (HR: 4.52, p=0.01), and treatment with 3D-conformal RT vs intensity-modulated RT (HR: 5.1, p=0.003). On multivariable analysis, pre-RT tooth extractions and RT technique remained significant. A dosimetric comparison between patients with and without MORN showed no significant differences. CONCLUSIONS AND RELEVANCE: The incidence of MORN is low in the modern era at a high volume academic center. Modifiable risk factors including pre-RT tooth extractions, smoking, and RT technique are associated with MORN, and the risk should be minimized with appropriate dental evaluation and treatment, smoking cessation efforts, and the use of intensity-modulated RT.
OBJECTIVES: To evaluate the incidence of, and risk factors associated with, mandibular osteoradionecrosis (MORN) following radiation therapy (RT) for oral cavity and oropharyngeal cancers. MATERIALS AND METHODS:Patient and treatment records of 252 consecutive patients with oral cavity or oropharynx cancers treated with RT by a single radiation oncologist at a high volume academic institution from August 2009 to December 2015 were retrospectively reviewed. A Cox regression model was used to assess factors associated with the development of MORN. RT dosimetry was compared between patients with MORN and a matched cohort of patients without MORN. RESULTS:MORN developed in 14 patients (5.5%), occurring 3-40 (median 8) months post-RT. Factors associated with MORN on univariable analysis included primary diagnosis of oral cavity vs oropharynx cancer (hazard ratio [HR]: 3.0, p=0.04), smoking at the time of RT (HR: 3.1, p=0.04), mandibular invasion of the primary (HR: 3.7, p=0.04), pre-RT tooth extraction (HR: 4.52, p=0.01), and treatment with 3D-conformal RT vs intensity-modulated RT (HR: 5.1, p=0.003). On multivariable analysis, pre-RT tooth extractions and RT technique remained significant. A dosimetric comparison between patients with and without MORN showed no significant differences. CONCLUSIONS AND RELEVANCE: The incidence of MORN is low in the modern era at a high volume academic center. Modifiable risk factors including pre-RT tooth extractions, smoking, and RT technique are associated with MORN, and the risk should be minimized with appropriate dental evaluation and treatment, smoking cessation efforts, and the use of intensity-modulated RT.
Authors: Hillary Nepon; Tyler Safran; Edward M Reece; Amanda M Murphy; Joshua Vorstenbosch; Peter G Davison Journal: Semin Plast Surg Date: 2021-09-10 Impact factor: 2.195