International Expert-Based Consensus Definition, Classification Criteria, and Minimum Data Elements for Osteoradionecrosis of the Jaw: An Interdisciplinary Modified Delphi Study

Abstract

Purpose: Osteoradionecrosis of the jaw (ORNJ) is a severe iatrogenic disease characterized by bone death after radiation therapy to the head and neck. With >9 published definitions and at least 16 classification systems, the true incidence and severity of ORNJ are obscured by lack of a standard for disease definition and severity assessment, leading to inaccurate estimation of incidence, reporting ambiguity, and likely underdiagnosis worldwide. This study aimed to achieve consensus on an explicit definition and phenotype of ORNJ and related precursor states through data standardization to facilitate effective diagnosis, monitoring, and multidisciplinary management of ORNJ.

Methods and materials: The Orodental Radiotherapy-Associated Late-Effects Consortium comprised 69 international experts, including representatives from medical, surgical, radiation oncology, and oral/dental disciplines. Using a web-based modified Delphi technique, panelists classified descriptive cases using existing classification systems, reviewed systems for feature extraction and specification, and iteratively classified cases based on clinical/imaging feature combinations.

Results: The Consortium ORNJ definition was developed in alignment with Systematized Nomenclature of Medicine - Clinical Terms (SNOMED-CT) terminology and recent International Society of Oral Oncology-Multinational Association for Supportive Care in Cancer and the American Society of Clinical Oncology (ISOO-MASCC-ASCO) guideline recommendations. Case review using existing ORNJ classification systems showed high rates of inability to classify (up to 76%). Ten consensus statements and 9 minimum data elements (MDEs) were outlined for prospective collection and classification of precursor/ORNJ disease states.

Conclusions: This study provides an international, consensus-based definition and MDE foundation for standardized ORNJ reporting in cancer survivors treated with radiation therapy. Head and neck surgeons, radiation, surgical, medical oncologists, and dental specialists should adopt MDEs to enable scalable health information exchange and analytics. Work is underway to develop both a human- and machine-readable knowledge representation for ORNJ (ie, ontology) and multidisciplinary resources for dissemination to improve ORNJ reporting in academic and community practice settings.

Fig. 1.

Delphi consensus process flowchart. Abbreviation: ORN = osteoradionecrosis.

Fig. 2.

Example case scenario for proposed timing of ORNJ diagnosis based on development of exposed and necrotic bone and timing of scheduled visits (A) and the distribution of expert responses (B). Abbreviation: ORNJ = osteoradionecrosis of the jaw.

Fig. 3.

Expert classification of 3 descriptive cases of potential ORNJ using 14 classification systems. Individual bars per graph represent available grade or stage classes per system and the total count of responses per class. Magenta bars correspond to the option “unable to classify” across all systems. Abbreviation: ORNJ = osteoradionecrosis of the jaw.

Fig. 4.

Case-based classifications. Panel (A) demonstrates expert distribution of ORNJ stage assignments (ie, Not precursor/Not ORNJ, Precursor/stage 0, Early ORNJ, Intermediate ORNJ, and Advanced ORNJ) for 10 cases evaluated, whereas Panel (B) illustrates expert-based opinions and distributions of likely extent of bone involvement identified for each case. Panel (C) includes boxplots of reported level of confidence in classification of each case stratified by grouped specialty, and Panel (D) presents and summarizes findings for case 8 of the study. Abbreviation: ORNJ = osteoradionecrosis of the jaw.