MII IG Kerndatensatz-Modul Onkologie
2027.0.0-ballot.1 - Germany

This page is part of the MII IG Kerndatensatz-Modul Onkologie (v2027.0.0-ballot.1: Release) based on FHIR (HL7® FHIR® Standard) R4. This is the current published version. For a full list of available versions, see the Directory of published versions

ICD-O: Revisions and Validation

Overview and Governance

The International Classification of Diseases for Oncology (ICD-O) is published by IARC on behalf of the WHO and describes neoplasms along two axes: topography (site, C… codes) and morphology (histology and behaviour, XXXX/B codes with a behaviour digit). The German-language edition is published by the BfArM on behalf of the Federal Ministry of Health.

In the Oncology module, topography is used at Condition.bodySite (primary tumour diagnosis) and morphology via the histology profiles and the extension mii-ex-onko-histology-morphology-behavior-icdo3.

Revisions: First (2014) and Second Revision (2019)

For ICD-O-3 there are two German revisions that occur side by side in legacy data:

Revision German edition Corresponds to Status
First revision 2014 ICD-O-3.1 widespread in cancer registry legacy data
Second revision 2019 ICD-O-3.2 current edition (publication completed 12/2020)

The second revision differs substantially (morphology axis: 124 new and 56 removed codes alongside approximately 1,080 unchanged ones; 55 verified against the server, plus 8153/1 per the official BfArM update list of 2021-01-29):

  • New codes mainly concern molecularly defined entities (e.g. 8023/3 NUT carcinoma, 8085/3/8086/3 HPV-positive/-negative squamous cell carcinoma).
  • Re-assessed behaviour: entities that the WHO uniformly classifies as malignant lost their /0 and /1 variants — among them GIST (8936/1 → 8936/3), phaeochromocytoma (8700/0 → 8700/3), thymomas type A–B3 (/1 → /3) and the paragangliomas (868x/869x).
  • Merged entities: e.g. Ewing sarcoma 9260/3 → 9364/3, haemangiopericytoma 9150/x → solitary fibrous tumour (8815/x), small lymphocytic lymphoma 9670/3 → CLL/SLL 9823/3.
  • Discontinued syndrome concepts without a successor (meningiomatosis 9530/1, neurofibromatosis 9540/1): here the individual tumours are to be coded.

Transition of Legacy Data

The ConceptMap mii-cm-onko-icdo3-transitions-2019 documents all 55 morphology-axis transitions with their degree of equivalence (analogous to the ATC transition ConceptMaps of systemic therapy):

  • equivalent — behaviour re-classifications and 1:1 merges,
  • wider — absorbed into a broader concept (e.g. refractory neutropenia/ thrombocytopenia → MDS with single lineage dysplasia 9980/3),
  • narrower — uncertain /1 concepts with several behaviour-specific successors (behaviour must be assigned case by case based on the findings),
  • unmatched — discontinued concepts with a coding hint in the comment.

It is intended as a tool for ETL pipelines and the migration of cancer registry legacy data; the transition does not replace a case-by-case clinical review.

Validation: Revisions Are Separate CodeSystem Resources

On the MII terminology server, ICD-O-3 — like ICD-10-GM, OPS and ATC — is held as separate CodeSystem resources per revision under one canonical URL (http://terminology.hl7.org/CodeSystem/icd-o-3, versions 2014 and 2019). Two rules follow from this:

  1. ValueSet filters must be version-pinned. With several revisions loaded, unpinned descendent-of filters fail because of version ambiguity — $validate-code with systemVersion=2014 then incorrectly returned not-in-valueset even though the code exists in both revisions. All ICD-O ValueSets of this module therefore pin their includes.
  2. Instances SHOULD state coding.version ("2014" or "2019") so that validation and analysis know the revision.

The binding of the profiles points to the union ValueSets of both revisions: legacy data of the first revision (including the codes removed in 3.2) and current data therefore validate equally. For revision-specific checks (data quality, ETL) the per-year ValueSets are available.

Technical Artifacts

Artifact Content Purpose
mii-vs-onko-icdo3-morphologie Morphology, union 2014 + 2019 Profile binding (tolerant for legacy and new data)
mii-vs-onko-icdo3-topographie Topography, union 2014 + 2019 Profile binding
mii-vs-onko-icdo3-morphologie-2014 / -2019 Morphology, revision-specific DQ checks, ETL, analysis per data stock
mii-vs-onko-icdo3-topographie-2014 / -2019 Topography, revision-specific DQ checks, ETL
mii-cm-onko-icdo3-transitions-2019 56 morphology transitions 3.1 → 3.2 Migration of legacy data

Outlook: ICD-O-4

IARC published the final tables of ICD-O-4 in early 2026 (WHO Classification of Tumours Online): a new morphology structure with five-digit morphology codes based on the 5th edition of the WHO Blue Books, harmonised with ICD-11. The book is in preparation; a German edition by the BfArM as well as a migration roadmap of the cancer registries are still pending. As soon as a German ICD-O-4 is published it will be integrated following the pattern established here: a revision-specific ValueSet plus a transition ConceptMap — whereby the move to five-digit codes will be a structurally larger step than the previous revisions.