Radiation Oncology Ontology - ROO

This is the landing page for the Radiation Oncology Ontology (ROO), which aims to cover the radiation oncology domain with a strong focus on re-using existing ontologies. There are many (~440) BioMedical Ontologies, of which some of the most popular are SNOMED CT, NCI Thesaurus, CTC AE, RadLex, ICD, LOINC, UMLS meta-theasurus. However, these do not include many of the Radiation Oncology terms, such as 

  • Uniform and non-uniform margins
  • ROI target volumes and organs-at-risk
  • Dose-Volume Histogram parameters (Dx, Vx, MLD, etc.)
  • On-line / off-line setup protocols, NAL, etc.

Radiation Oncology OntologyTherefore, we started the ROO with the following in mind:

  • Reuse other ontologies as much as possible, only add stuff that is not there yet
  • Free, open-access (incl. its re-used ontologies)
  • Deprecate but never delete
  • Published at the Bioportal
  • Quality: Update “official edition” twice a year
  • Flexibility: Community feedback, local additions, intermediate beta-versions
  • Governance currently project based -> ESTRO/ASTRO/AAPM
  • Tool: Protégé / Web Protégé


The ROO is published via the BioPortal of the National Center for Biomedical Ontology: http://bioportal.bioontology.org/ontologies/ROO
The latest version of the ROO can be found here: https://github.com/RadiationOncologyOntology/ROO

For background information, please refer to our White Paper.