Osteoradionecrosis Rates After Head and Neck Radiation Therapy: Beyond the Numbers

Osteoradionecrosis (ORN) is a severe late complication of head and neck radiotherapy shown to have profound negative impact on the quality of life of cancer survivors. Over the past few decades, improvements in radiation delivery techniques have resulted in a decrease in the incidence of ORN. However, even with modern radiotherapy techniques, ORN remains an important clinical concern. In recent literature, there is a wide range of reported ORN rates from 0% to as high as 20%. With such a high level of variability in the reported incidence of ORN, oncologists often encounter difficulties estimating the risk of this serious radiotherapy toxicity. In this review, the authors present a summary of the factors that contribute to the high level of variability in the reported incidence of ORN, and highlight that the variable definition, variable grading, and heterogeneity of both study inclusion criteria and treatment parameters can each significantly influence the reporting of ORN rates. Given numerous factors can affect the reported incidence of ORN, a thorough understanding of the clinical context behind the reported ORN rates is needed to comprehend the true risk of this important radiotherapy toxicity.